Conference Program of WCICA 2012

Conference Program WCICA 2012
Gui, Weihua
Central South Univ.
Sun, Xue
Nanjing Normal Univ.
This paper investigates parametric stability of nonlinear systems with
uncertain parameters based on decentralized control. The main concern
is that the equilibrium of the closed-loop system drifts with the
change of the parameters. First, the impact of the parameters on the
equilibrium location is investigated. Then, a decentralized linear controller
is designed to make the closed-loop system parametrically stable.
The proposed method combines different optimization techniques
to produce a robust control that accounts for uncertain parametric variations,
and the corresponding equilibrium shifts. Finally, simulation results
are given to show the effectiveness of the proposed method.
SuA02 13:30–15:30 Room 203B
Multi-Agent Systems (I)
Chair: Cai, Yunze
Co-Chair: Zhang, Zhenning
Shanghai Jiao Tong Univ.
Chinese Acad. of Sci.
◮ SuA02-1 13:30–13:50
Multi-agent Competitive Control Systems, pp.2263–2267
Zhang, Zhenning
Cheng, Daizhan
Chinese Acad. of Sci.
Chinese Acad. of Sci.
In this paper, we consider the multi-agent competitive control systems
with varying adjacent topology. The dynamics and the performance
of each agent of the multi-agent system depend on both itself and its
neighborhood. The optimal solutions are the Nash equilibriums, which
are determined by coupled Hamilton-Jacobi-Bellman equations. We
mainly concern with continuous-time affine nonlinear systems and linear
systems. Finally, a two-agent linear control system is used to illustrate
our results, where the two agents are related through a periodic
switching.
◮ SuA02-2 13:50–14:10
Flocking of Multi-Agents Based on Consensus Protocol and Pinning
Control, pp.1311–1316
He, Chenlong
Feng, Zuren
Ren, Zhigang
Xi’an Jiaotong Univ.
Xi’an Jiaotong Univ.
Xi’an Jiaotong Univ.
In this paper we propose three controllers for flocking of multi-agent system,
which are basic linear controller, controller with actuator saturation
and controller with time delay under the condition that the information
exchanging topology of agents is connected and fixed. Each controller
is composed of two components as consensus algorithms for making
the entire agents converge to a common state and pinning control for
guiding the agents to the desired moving direction. The stability of controllers
is analyzed and the effectiveness of controllers is demonstrated
by numerical simulation.
◮ SuA02-3 14:10–14:30
Distributed Event-triggered Tracking Control of Multi-Agent Systems
with Active Leader, pp.1453–1458
Zhang, Yanqiong Acad. of Mathematics & Sys. Sci., Chinese
Acad. of Sci.
Hong, Yiguang
Chinese Acad. of Sci.
Event-triggered control is an effective protocol to design distributed control
of multi-agent systems with the limited resources. In this paper, we
consider a multi-agent tracking problem for a linear active leader based
on event-triggered control. The state of the leader keeps changing and
may not be measured. To estimate the state such a leader individually,
a neighbor-based local controller together with a neighbor-based
state-estimation rule is given for each autonomous agent, and the communication
of the agents under consideration is event-driven. Then we
prove that, with a constructed common Lyapunov function for switching
topology, each agent can track the active leader with unmeasurable
states.
◮ SuA02-4 14:30–14:50
On Necessary and Sufficient Conditions of the Consensusabilityfor
Second-order Discrete Multi-agent Systems, pp.1727–1732
Zhu, Jiandong
Nanjing Normal Univ.
In this paper, necessary and sufficient conditions of the consensusability
are obtained for second-order discrete multi-agent systems without
assuming that all the eigenvalues of each agent’s dynamical equation
lie on or outside the unit circle, which is a basic assumption in [1]. The
obtained results show that, if each agent’s dynamical equation has a
stable eigenvalue, the condition ∏︀ j |λu j
(A)| < (1 + r)/(1 − r) obtained
in [1] may not be necessary anymore, where λ u j
(A) denotes
each unstable eigenvalue of the coefficient matrix A of every agent and
r the eigenratio of the graph. Consensus protocols are designed for
some numerical examples that do not satisfy the above condition in [1].
Moreover, using the proposed method in this paper, all the possible
control gains can be designed constructively.
◮ SuA02-5 14:50–15:10
Distributed Filtering Basing Consensus for the Local Strongly Coupled
Systems, pp.1801–1805
Cai, Yunze
Wang, Hua O.
Xu, Xiaoming
Shanghai Jiao Tong Univ.
Boston Univ.
Shanghai Jiao Tong Univesity;
The interactions between subsystems are important for large-scale systems.
We introduce a local strongly coupled system which coupled by
random communication between subsystems. Due to the intermittent
communication, it is difficult to apply the standard Kalman or robust filter
to design procedures to such systems. In this paper, we addressed the
distributed robust filter design method for this kind of system based on
consensus idea. The main result is a sufficient condition which guarantees
a suboptimal level of disagreement of estimates in a coupled
network of estimators. The condition is formulated in terms of feasibility
of biaffine matrix inequalities (BMIs). The generic algorithm is
used to treat the bilinear relation between filter parameters and the interconnection
gains. The proposed approach is applied to the problem
of formation-based robust synchronization. The numerical simulations
show the effectiveness of the proposed filtering method.
◮ SuA02-6 15:10–15:30
Decentralized Sweep Algorithm of Multi-agent Systems with Adaptive
Workload Assignment, pp.4320–4325
Zhai, Chao
Hong, Yiguang
Chinese Acad. of Sci.
Chinese Acad. of Sci.
This paper discusses decentralized sweep coverage of a given region
with parametric uncertainties by multiple agents. With parametric uncertainty
in the environment, we present an adaptive sweep coverage
algorithm to guarantee the region coverage by sweeping and workload
partition. The adaptive technique with persistence condition is employed
to sweep an unbounded region, and the upper bound for the
extra time spent due to the environmental uncertainty is estimated for
the covered region.
SuA03 13:30–15:30 Room 203C
Image Processing
Chair: Yang, Wankou
Co-Chair: Yu, Xiao
Southeast Univ.
Univ. of Sci. & Tech. Beijing
◮ SuA03-1 13:30–13:50
Compression of MR-Thermometry Images Using Reduced-Order
Karhunen-Lo‘eve Basis, pp.4655–4660
Niu, Ran
GE Global Research (Shanghai)
In this paper, we develop an approach to achieve MR thermal image
compression by exploiting the spatial correlations of image voxels during
thermal treatment. A set of reduced-order basis was identified using
Karhunen-Lo‘eve (KL) decomposition of MR thermal images. Each
image can be compressed with a relative small number of identified
KL basis functions. The proposed approach can be used in real-time
compression of imaging data in order to minimize a potentially massive
amount of information that must be exchanged between the MR
scanner and the treatment controller, and reduce computer storage requirements
during thermal treatment. Simulation and MR thermometry
experimental results demonstrate that the proposed image compres-
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