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Automatic Anterior Lamina Cribrosa Surface Depth Measurement Based on Active Contour and energy constraint

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Journal of Computer Science & Technology 2017年第6期32卷 1214-1221页

作者： Zai-Liang Chen Peng Peng Bei-Ji Zou Hai-Lan Shen Hao Wei Rong-Chang Zhao School of Information Science and Engineering Central South University Changsha 410083 China Center for Ophthalmic Imaging Research Central South University Changsha 410083 China 'Mobile Health' Ministry of Education-China Mobile Joint Laboratory Central South University Changsha 410083 China

The lamina cribrosa is affected by intraocular pressure, which is the major risk of glaucoma. However, the capability to evaluate the lamina cribrosa in vivo has been limited until recently due to poor image quality and the posterior laminar displacement of glaucomatous eyes. In this study, we propose an automatic method to measure the anterior lamina cribrosa surface depth （ALCSD）, including a method for detecting Bruch＇s membrane opening （BMO） based on k-means and region-based active contour. An anterior lamina cribrosa surface segmentation method based on energy constraint is also proposed. In BMO detection, we initialize the Chan-Vese active contour model by using the segmentation map of the k-means cluster. In the segmentation of anterior lamina cribrosa surface, we utilize the energy function in each A-scan to establish a set of candidates. The points in the set that fail to meet the constraints are removed. Finally, we use the B-spline fitting method to obtain the results. The proposed automatic method can model the posterior laminar displacement by measuring the ALCSD. This method achieves a mean error of 45.34 μm in BMO detection. The mean errors of the anterior lamina cribrosa surface are 94.1% within five pixels and 76.1% within three pixels.

关键词： anterior lamina cribrosa surface segmentation active contour energy constraint measurement

Distributed filtering for time-varying networked systems with sensor gain degradation and energy constraint: a centralized finite-time communication protocol scheme

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Science China(Information Sciences) 2018年第9期61卷 241-255页

作者： Ye ZHAO Xiao HE Donghua ZHOU National Laboratory for Information Science and Technology (TNList) and Department of Automation Tsinghua University College of Electrical Engineering and Automation Shandong University of Science and Technology

This paper focuses on the distributed filtering problem for a class of time-varying networked systems with sensor gain degradation and energy constrained communication protocol. To satisfy the requirement of power consumption and reduce the schedule computing complexity, centralized cyclic finite-time communication strategy optimization is taken into account. The networked system considered in this paper consists of spatially distributed sensors linked to their neighbor sensors, where each sensor node suffers from different gain degradation, and the transmission decisions of all the communication channels obey the centralized transmission schedule strategy identically. First, we present scattered communication action based on single-sensor transmission modeling with an energy constraint. Subsequently, an optimal communication protocol considering expected average error covariance is derived between the target system and each sensor node over the distributed sensor systems, based on a centralized finite-time scheme. Finally, by transforming the overall estimation error covariance of the systems at each sampling time into quadratic form, a conditionally unbiased least-square recursive distributed filtering technique over the networked system is designed at each sensor node. The system stability condition under such an optimal schedule is also accomplished with bounded covariance. A numerical example is provided to demonstrate the utility and effectiveness of the distributed filtering technique using the proposed optimized energy constrained communication protocol.

关键词： networked systems distributed filtering communication protocol centralized finite-time schedule energy constraint sensor gain degradation

Distributed Coverage Control for Multi-Agent Systems with energy constraint and Balance

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Distributed Coverage Control for Multi-Agent Systems with En...

Novel radar dwell scheduling algorithm based on pulse interleaving

第三十九届中国控制会议

作者： Zhi Zheng College of Mathematics and Informatics Fujian Normal University

Coverage control is one of the main applications of multi-agent systems. In this paper, we study the distributed dynamic coverage control problem for the multi-agent system with second-order Euler-Lagrangian dynamics, considering energy limitation and energy consumption balance. First, EVoronoi partition, i.e., Voronoi partition based on remaining energy is designed. We prove that the EVoronoi partition coverage is distributed, and its local minimum is the optimal location for deployment. Each agent only needs to exchange information with its neighbors, and no global information is needed. Then, we design a control law based on the energy constraints of the agents. It is proved by Lyapunov theory that the control law will make the system converge to the optimal coverage position, such that the coverage is maximum, and it ensure that each agent’s energy is not lower than the specified lower bound, while maintaining the energy balance in the multi-agent system. Simulation results are given to validate the theoretical results.

关键词： Distributed Optimal Deployment energy constraint

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Journal of Systems Engineering and Electronics 2009年第2期20卷 247-253页

作者： Cheng Ting He Zishu Tang Ting School of Electronic Engineering Univ. of Electronic Science and Technology Chengdu 610054 P. R. China

The problem of scheduling radar dwells in multifunction phased array radar systems is addressed. A novel dwell scheduling algorithm is proposed. The whole scheduling process is based on an online pulse interleaving technique. It takes the system timing and energy constraints into account. In order to adapt the dynamic task load, the algorithm considers both the priorities and deadlines of tasks. The simulation results demonstrate that compared with the conventional adaptive dwell scheduling algorithm, the proposed one can improve the task drop rate and system resource utility effectively.

关键词： dwell scheduling pulse interleaving energy constraint priority deadline

Practical Realization of Optimal Auxiliary Frequency Control Strategy of Wind Turbine Generator

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Journal of Modern Power Systems and Clean energy 2022年第3期10卷 617-626页

作者： Ming Sun Yong Min Xuejun Xiong Lei Chen Le Zhao Yuyao Feng Bingran Wang IEEE State Key Laboratory of Power System and Generation Equipment Department of Electrical EngineeringTsinghua UniversityBeijing 100084China State Grid Shanghai Electric Power Research Institute Shanghai 200437China School of New energy Harbin Institute of Technology(Weihai)Weihai 264209China

Adding the auxiliary frequency control function to the wind turbine generator(WTG)is a solution to the frequency security problem of the power system caused by the replacement of the synchronous generator(SG)by the *** auxiliary frequency control using rotor kinetic energy is an economical scheme because the WTG still runs at the maximum power point during normal *** this paper,the functional optimization model of the auxiliary frequency control strategy of WTG is *** optimal auxiliary frequency control strategy is obtained by solving the model *** for the practical realization of the control strategy,the coordination of the auxiliary frequency control with the maximum power point tracking(MPPT)control is *** practical auxiliary frequency control strategy is modified to adapt to different power disturbances in the system,and the parameter setting method is also *** sensitivity of system frequency to control parameters is ***,the simulation results verify the effectiveness and practicability of the proposed control strategy.

关键词： Power system frequency security wind turbine generator auxiliary frequency control rotor kinetic energy energy constraint

MIMO radar dwell scheduling based on novel pulse interleaving technique

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Journal of Systems Engineering and Electronics 2013年第2期24卷 234-241页

作者： Ting Cheng Wenwen Liao Zishu He School of Electronic Engineering University of Electronic Science and Technology of China

According to the signal processing characteristic of MIMO radars,an adaptive dwell scheduling algorithm is *** is based on a novel pulse interleaving technique,which makes full use of transmitting,waiting and receiving durations of radar *** utilization of transmitting duration is unique for MIMO radars and is realized through transmitting duration *** results show that,compared with the conventional scheduling algorithm,the scheduling performance of MIMO radars can be improved effectively by the proposed algorithm,and the scheduling rule can be chosen arbitrarily when using the proposed algorithm.

关键词： multiple input multiple output(MIMO) radar dwell scheduling pulse interleaving time constraint energy constraint

energy-Efficient Optimal Scheme Based on Mixed Routing in Wireless Sensor Networks

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Energy-Efficient Optimal Scheme Based on Mixed Routing in Wi...