Robust Finite-time Guaranteed Cost Control for Impulsive Switched Systems with Time-varying Delay

Guang-Deng Zong,Xiaohong Wang,Haijuan Zhao 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.1

This paper is concerned with the problem of robust finite-time guaranteed cost control for a class ofimpulsive switched systems with time-varying delay. Firstly, the definitions of finite-time boundedness, finite-timestabilization, and robust finite-time guaranteed cost control are presented. Next, based on the average dwell-timeapproach, sufficient conditions on robust finite-time guaranteed cost control are obtained for the uncertain impulsiveswitched systems. Then, by using multiple Lyapunov-like functional method and linear matrix equality (LMI)technique, the state feedback controller is designed to guarantee that the uncertain impulsive switched system isfinite-time stabilized. Furthermore, a finite-time guaranteed cost bound is given. Finally, a numerical example isshown to illustrate the effectiveness of the proposed results.

Stability Analysis of Switched Delay Systems with All Subsystems Unstable

Guang-Deng Zong,Qingzhi Wang,Haibin Sun 제어·로봇·시스템학회 2016 International Journal of Control, Automation, and Vol.14 No.5

The stability problem of switched delay systems with all subsystems unstable is investigated in this paper. A sufficient criterion is firstly proposed to guarantee asymptomatic stability of nonlinear switched delay systemswith all subsystems unstable, where the stabilization property of switching behaviors is exploited to compensate thedivergence of states. Then by constructing multiple discretized Lyapunov-Krasovskii functionals, stability criteriaare developed for linear switched time-invariant and time-varying delay systems with all subsystems unstable. Finally, two examples are provided to illustrate the feasibility, superiority and application of the proposed approach.

유명 콘텐츠를 원작으로 한 ‘다크라이드’ 사례

장광종(Guang-Zong Zhang),채일진(Eel-Jin Chae),유상수(Sang-Soo Yoo) 한국애니메이션학회 2014 한국애니메이션학회 학술대회지 Vol.2014 No.5

Degradation Model and Evaluation Criteria for the Seismic Behavior of Corrosion H-section Steel Column

Guang-chong Qin,Tao Lan,Qing Qin,Shan-hua Xu,Zong-xing Zhang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.8

The cross section would be reduced and the material properties of the steel structure would be deteriorated under the corrosion environment, which will have different effects on the earthquake resistant behavior. This paper takes corroded H-steel column as the research object. Firstly, the influence on the failure mode, bearing capacity, hysteretic properties, ductility and hysteretic energy is analyzed from specific factors which consist of different width-to-thickness on flange, different height-to-thickness on web and different axial compression ratios by FEA. The results show that, the area of the hysteresis loop diminishes gradually, the bearing capacity decrease clearly, the accumulative energy dissipation and ductility coefficient decreased continuously, and the degradation laws of buckling load, peak load, hysteretic energy and ductility coefficient of corroded H-steel columns are thereby established. When the thickness of flange decreased by 30%, the peak load decreased by 32% and hysteretic energy decreased by 77%. However, the peak load decreased by 14% and hysteretic energy decreased by 40% when the thickness of web decreased by 30%. When the axial compression ratio is 0.6, and the mass loss ratio of corroded H-steel columns reached 22%, the peak load and hysteretic energy decreased by 28% and 51% respectively. Secondly, the hysteretic model of load-displacement of corroded H-steel members under cyclic loading is proposed based on the simulation results and the degradation model of characteristic point of skeleton line was given. Finally, the evaluation criteria are proposed based on the seismic performance objectives, and the classification of failure types as well as the overall performance evaluation of corroded steel members are carried out.

Impact effect analysis for hangers of half-through arch bridge by vehicle-bridge coupling

Shao, Yuan,Sun, Zong-Guang,Chen, Yi-Fei,Li, Huan-Lan Techno-Press 2015 Structural monitoring and maintenance Vol.2 No.1

Among the destruction instances of half-through arch bridges, the shorter hangers are more likely to be ruined. For a thorough investigation of the hanger system durability, we have studied vehicle impact effect on hangers with vehicle-bridge coupling method for a half-through concrete-filled-steel-tube arch bridge. A numerical method has been applied to simulate the variation of dynamic internal force (stress) in hangers under different vehicle speeds and road surface roughness. The characteristics and differences in impact effect among hangers with different length (position) are compared. The impact effect is further analyzed comprehensively based on the vehicle speed distribution model. Our results show that the dynamic internal force induced by moving vehicles inside the shorter hangers is significantly greater than that inside the longer ones. The largest difference of dynamic internal force among the hangers could be as high as 28%. Our results well explained a common phenomenon in several hanger damage accidents occurred in China. This work forms a basis for hanger system's fatigue analysis and service life evaluation. It also provides a reference to the design, management, maintenance, monitoring, and evaluation for this kind of bridge.

Asynchronous H∞ Control for Positive Discrete-time Markovian Jump Systems

Hui Shang,Wenhai Qi,Guang-Deng Zong 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.2

This paper deals with the asynchronous H∞ control for discrete-time positive Markovian jump systems (PMJSs). In previous results about PMJSs, asynchronous behaviors are always overlooked and the designed controller is based on the synchronization between the system modes and controller modes. Sufficient conditions for stochastic stability are proposed by the use of Lyapunov-Krasovskii functional. The asynchronous controller is designed to ensure the closed-loop system stochastically stable with a prescribed H∞ performance index. All the conditions are given in linear matrix inequality framework. Finally, a pest’s age-structured population dynamic model is illustrated to show the validity of the present design.

Finite-time Control for Discrete-Time Switched Systems with Time Delay

Lin-Lin Hou,Guang-Deng Zong,Yu-Qiang Wu 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.4

The problem of finite-time state feedback control is considered in this paper for a class of discrete-time switched systems with time delay. Firstly, the concepts of finite-time stability and finite-time boundedness are extended to discrete-time switched systems with time delay, respectively. Then, by re-sorting to the average dwell time approach and Lyapunov-Krasovskii functional technology, some new delay-dependent criteria guaranteeing finite-time boundedness and stability are developed. The state feedback controller is also obtained by virtue of a cone complement linearization (CCL) method. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed results.

Comparison of Two Cases of Strong Increase in the Bottom Temperature in the Yellow Sea in Winter

Lian-Gang Lü,Guang-Bing Yang,Zong-Wei Liu,Ying Jiang,Chunmei Yang,Chao Zhang 한국해양과학기술원 2015 Ocean science journal Vol.50 No.3

Mooring observations were carried out on the western slope of the southern Yellow Sea (YS) to observe the Yellow Sea Warm Current (YSWC). Strong increases in the bottom temperature (about 3°C within 1 day) were observed at mooring M5 (shelf break) on 8 January 2007, and at mooring A2 (mid-slope) on 5 December 2008. The strong temperature increase of bottom water at M5 was closely related to the burst of the YSWC. The bottom temperature at mooring A2 increased and decreased alternately from 7 November to 14 December 2008, and the strong increase (about 3°C within 1 day) occurring on 5 December was one of the four rises during that period. The significant semi-diurnal-oscillation during that period indicated that the thermal fronts outlining the Yellow Sea Cold Water Mass (YSCWM) boundary was very close to location A2. The notable rises in the bottom temperature at A2 were associated with bottom eastward currents, while the distinct falls in temperature coincide with bottom westward currents. The distinctive distribution in the bottom temperature associated with the YSCWM and the bottom eastward currents were mainly responsible for the strong increase in the bottom temperature at A2. The variations in the bottom temperature described here are valuable for understanding the time evolution of the YSWC in winter and the YSCWM from late autumn to early winter.

Significance of Oligoclonal Bands after Stem Cell Transplantation in Multiple Myeloma Cases

Liu, Ai-Jun,Zong, Hong,Yang, Guang-Zhong,Zhai, Yu-Hua,Li, Li-Hong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Objective: To determine the characteristics of oligoclonal bands that are frequently detected by serum protein electrophoresis (SPEP) and immunofixation electrophoresis (IFE) after stem cell transplantation. Methods: We retrospectively analyzed 56 patients with multiple myeloma (MM) undergoing transplantation, and standard immunofixation electrophoresis was used to identify and quantify paraproteins. Results: The median follow-up was 35 months (range, 10-76months) and 21 patients relapsed. Twelve (25.0%) demonstrated oligoclonal bands after a median time 1.4 months (range, 1-3months), with a median duration of 5.8 months (range, 1-15months). The majority patients with oligoclonal bands had normal quantities of immunoglobulins and the one year event free survival (EFS) was 92%, even higher than for patients without OBs (P=0.002). Conclusion: Oligoclonal bands frequent develop post-transplantation in MM cases. In the vast majority of patients, they may not represent relapsed disease, and more likely represent a transient phenomenon representing recovery of impaired immunoglobulin production.

The Effectiveness of Postoperative Chemotherapy on pT1bN0 and pT2N0 Gastric Cancer Patients with Risk Factors: An International Dual-Center Analysis

Kun Yang,Mo-Xi Chen,최윤영,Zong-Guang Zhou,형우진,노성훈,Jian-Kun Hu 연세대학교의과대학 2021 Yonsei medical journal Vol.62 No.2

Purpose: This study aimed to investigate the effectiveness of postoperative chemotherapy in pT1bN0 and pT2N0 gastric cancerpatients with high risk factors. Materials and Methods: Clinicopathological data of gastric cancer patients, who had undergone gastrectomy in high volumecenters in Korea and China and were finally diagnosed with pT1bN0 and pT2N0 between 2006 and 2010, were analyzed retrospectively. Survival analyses stratified by risk factors and multivariable analyses were performed. Results: A total of 1509 patients were enrolled, with 41 (2.7%) patients receiving adjuvant chemotherapy after gastrectomy and1468 (97.3%) patients undergoing surgery alone. The adjuvant chemotherapy group showed higher percentages of tumor withmaximal diameter >3 cm (51.2% vs. 25.8%), poor differentiation (68.3% vs. 49.8%), and less harvested lymph nodes (17.1% vs. 5.2%) compared to the surgery alone group. The overall survival rates were 95.1% in the adjuvant chemotherapy group and 93.3%in the surgery alone group, without significant difference. In multivariable analysis, age was found to be an independent prognosticfactor. However, there were no difference in the overall survival between patients with risk factors and those without risk factors,even in terms of age. Meanwhile, patients with more than two risk factors who received chemotherapy showed better survivaltrend, especially for pT2N0 patients, compared to the surgery alone group, although no significant differences were observed. Conclusion: In pT1bN0 and pT2N0 patients, age was found to be an independent prognostic factor. However, adjuvant chemotherapyseemed to be unnecessary, while postoperative chemotherapy might offer survival benefits to pT2N0 patients with morethan two risk factors.