检索结果-内蒙古大学图书馆

Anomaly Detection of Markov Processes with Evolution Equation and Moments ⁎

学校读者我要写书评

暂无评论

IFAC-PapersOnLine 2020年第2期53卷 1974-1979页

作者： Rafal Wisniewski Manuela L. Bujorianu Section of Automation & Control Department of Electronic Systems Aalborg University Fredrik Bajers Vej 7C 9220 Aalborg Denmark Maritime Safety Research Center Department of Naval Architecture Ocean & Marine Engineering University of Strathclydes G4 0LZ Glasgow Scotland UK

Our departure point is the evolution equation of a Markov process. It describes the changes in the transition probability as time passes. We compare the transition probability for a priori model with the actual transition probability of the observed process to detect a mismatch between the expected and the measured data. To translate this idea into an algorithm, we characterise the involved measures by their moments. Specifically, a linear dynamic system is put forward that describes the evolution of moments. As the last result, we define a moment divergence as the means of computing the distance between two sequences of moments. We see the work as a step towards merging model-driven and data-driven concepts in control engineering. To elucidate the concepts introduced, we have incorporated several simple examples.

关键词：

Reinforcement Learning for Mixing Loop control with Flow Variable Eligibility Trace

学校读者我要写书评

暂无评论

Reinforcement Learning for Mixing Loop Control with Flow Var...

control technology and Applications (CCTA),

作者： Anders Overgaard Brian Kongsgaard Nielsen Carsten Skovmose Kallesøe Jan Dimon Bendtsen Core Technology -Department of Control Technology Grundfos Holding A/S Bjerringbro Denmark Department of Electronic Systems section of Automation and Control alborg University Aalborg Denmark

Mixing Loops are often used for proper pressurization and temperature control in building thermal systems. Optimal control of the mixing loop maximizes comfort while minimizing cost. To ensure optimal control for mixing loops in a wide range of different buildings with different load conditions, a self learning controller is here proposed. The controller uses Reinforcement Learning with flow variable eligibility trace. The controller is shown to improve performance of the mixing loop control compared to state of the art reinforcement learning and industrial grade controllers. The controller is tested on a hardware in the loop setup for rapid testing of mixing loop control used in building heating.

关键词： Buildings Learning (artificial intelligence) Heating systems Hydraulic systems Delays Monte Carlo methods

Potential of fat-soluble vitamins as a platform for antiviral drug development

学校读者我要写书评

暂无评论

Bioorganic & medicinal chemistry letters 2025年 127卷 130292页

作者： Yoshihisa Hirota Mika Okamoto Masanori Baba Yoshitomo Suhara Laboratory of Biochemistry Department of Bioscience and Engineering College of Systems Engineering and Science Shibaura Institute of Technology 307 Fukasaku Minuma-ku Saitama 337-8570 Japan. Division of Infection Control Research Center for Advanced Science Research and Promotion Kagoshima University 1-21-24 Korimoto Kagoshima 890-8580 Japan. Laboratory of Organic Synthesis and Medicinal Chemistry Department of Bioscience and Engineering College of Systems Engineering and Science Shibaura Institute of Technology 307 Fukasaku Minuma-ku Saitama 337-8570 Japan. Electronic address: suhara@shibaura-it.ac.jp.

Fat-soluble vitamins, including vitamins A, D, E, and K, exhibit antioxidative, anti-inflammatory, and immunomodulatory effects, making them promising candidates for antiviral drug development. This review highlights their structural features, biological roles, and antiviral potential. Vitamin A derivatives modulate immunity and inhibit viral replication, including SARS-CoV-2. Vitamin D analogs enhance immune responses and target viral enzymes, while vitamin E derivatives reduce oxidative stress and may directly inhibit viral replication. Emerging research on vitamin K derivatives suggests potential antiviral applications. These findings underscore the potential of fat-soluble vitamins as innovative antiviral agents, warranting further investigation to optimize efficacy and clinical use.

关键词： Antiviral effect Derivatives Fat-soluble vitamins Immunomodulatory Structure-activity relationship

ESND: An embedding-based framework for signed network dismantling

学校读者我要写书评

暂无评论

Expert systems with Applications 2025年 289卷

作者： Chenwei Xie Chuang Liu Cong Li Xiu-Xiu Zhan Xiang Li Research Center for Complexity Sciences Hangzhou Normal University Hangzhou 311121 China Department of Electronic Engineering School of Information Science and Technology Adaptive Networks and Control Lab Fudan University Shanghai 200433 China College of Media and International Culture Zhejiang University Hangzhou 310058 China Research Institute of Intelligent Complex Systems Fudan University Shanghai 200433 China

Network dismantling aims to maximize the disintegration of a network by removing a specific set of nodes or edges and is applied to various tasks in various domains, such as cracking down on crime organizations, delaying the propagation of rumors, and blocking the transmission of viruses. Most of the current network dismantling methods are tailored for unsigned networks, which only consider the connection between nodes without evaluating the nature of the relationships, such as friendship/hostility, enhancing/repressing, and trust/distrust. We here propose an embedding-based algorithm, namely ESND, to solve the signed network dismantling problem. The algorithm generally iterates the following four steps, i.e., giant component detection, network embedding, node clustering, and removal node selection. To illustrate the efficacy and stability of ESND, we conduct extensive experiments on six signed network datasets as well as null models, and compare the performance of our method with baselines. Experimental results consistently show that the proposed ESND is superior to the baselines and displays stable performance with the change in the network structure. Additionally, we examine the impact of sign proportions on network robustness via ESND, observing that networks with a high ratio of negative edges are generally easier to dismantle than networks with high positive edges.

关键词： Network dismantling Node clustering Node embedding Signed network

Learning Hidden Markov Models for Linear Gaussian systems with Applications to Event-based State Estimation

学校读者我要写书评

暂无评论

arXiv 2020年

作者： Zheng, Kaikai Shi, Dawei Shi, Ling State Key Laboratory of Intelligent Control and Decision of Complex Systems School of Automation Beijing Institute of Technology Beijing100081 China Department of Electronic and Computer Engineering Hong Kong University of Science and Technology Kowloon Hong Kong

This work attempts to approximate a linear Gaussian system with a finite-state hidden Markov model (HMM), which is found useful in solving sophisticated event-based state estimation problems. An indirect modeling approach is developed, wherein a state space model (SSM) is firstly identified for a Gaussian system and the SSM is then used as an emulator for learning an HMM. In the proposed method, the training data for the HMM are obtained from the data generated by the SSM through building a quantization mapping. Parameter learning algorithms are designed to learn the parameters of the HMM, through exploiting the periodical structural characteristics of the HMM. The convergence and asymptotic properties of the proposed algorithms are analyzed. The HMM learned using the proposed algorithms is applied to event-triggered state estimation, and numerical results on model learning and state estimation demonstrate the validity of the proposed algorithms. Copyright © 2020, The Authors. All rights reserved.

关键词： Hidden Markov models

Regret and cumulative constraint violation analysis for online convex optimization with long term constraints

学校读者我要写书评

暂无评论

arXiv 2021年

作者： Yi, Xinlei Li, Xiuxian Yang, Tao Xie, Lihua Chai, Tianyou Johansson, Karl H. School of Electrical Engineering and Computer Science and Digital Futures KTH Royal Institute of Technology Stockholm Sweden Department of Control Science and Engineering College of Electronics and Information Engineering Shanghai Research Institute for Intelligent Autonomous Systems Institute for Advanced Study Tongji University Shanghai China State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang China School of Electrical and Electronic Engineering Nanyang Technological University Singapore Singapore

This paper considers online convex optimization with long term constraints, where constraints can be violated in intermediate rounds, but need to be satisfied in the long run. The cumulative constraint violation is used as the metric to measure constraint violations, which excludes the situation that strictly feasible constraints can compensate the effects of violated constraints. A novel algorithm is first proposed and it achieves an O(Tmax{c,1-c}) bound for static regret and an O(T (1-c)/2) bound for cumulative constraint violation, where c ϵ (0, 1) is a user-defined trade-off parameter, and thus has improved performance compared with existing results. Both static regret and cumulative constraint violation bounds are reduced to O(log(T )) when the loss functions are strongly convex, which also improves existing results. In order to achieve the optimal regret with respect to any comparator sequence, another algorithm is then proposed and it achieves the optimal O( p T (1 + PT )) regret and an O(√T) cumulative constraint violation, where PT is the path-length of the comparator sequence. Finally, numerical simulations are provided to illustrate the effectiveness of the theoretical results. Copyright © 2021, The Authors. All rights reserved.

关键词： Comparators (optical)

control strategy for suppressing submodule capacitor voltage fluctuation in cascaded H-bridge solidstate transformer

学校读者我要写书评

暂无评论

Control strategy for suppressing submodule capacitor voltage...

2021 Annual Meeting of CSEE Study Committee of HVDC and Power electronics (HVDC 2021)

作者： L. Liu L. Zhao J. Zhang D. Xi J. Zhou X. Feng H. Chen A. Zhang Z. Wang C. Tian Department of Electrical Engineering Inner Mongolia University of Technology Aimin St. 49 Hohhot China Mechatronic Systems Engineering Simon Fraser University 250-13450 102 Ave Surrey Canada The Key Laboratory of Control of Power Transmission and Conversion of Ministry of Education Department of Electrical Engineering School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University No.800 Dongchuan Rd. Shanghai China Donghua University School of Information Sciences and Technology No.2999 People North Rd. Shanghai China

Nowadays, with the vigorous development of smart grids, cascaded H-bridge solid-state transformers (CHB-SST) used in distribution network systems have gradually become an important research hotspot. The multiport CHB-SST serves as the interfacing device to interconnect different grids, which has the functions of bidirectional, power flow control, reactive power compensation, and voltage regulation. However, the power fluctuation of the power cells should be constrained by the large capacitors which in turn worsens the system power density. The second order current in the DC-link side of the CHB-SST will cause the fluctuation of the submodule (SM) capacitor voltage, affecting the capacitance value selection. Therefore, this paper proposes a method to suppress the SM capacitor voltage fluctuation of CHB-SST through fluctuating power control strategy. The control scheme passes the second order current component of the SM capacitor to the low-voltage side of the CHB-SST to reduce the voltage fluctuation of the SM capacitor, such that the capacitance can be optimized. The proposed method is verified via the MATLAB/Simulink model, proving that the fluctuation of the SM capacitor voltage can be effectively suppressed.

关键词：

Local Partial Zero-Forcing Combining for Cell-Free Massive MIMO systems

学校读者我要写书评

暂无评论

arXiv 2022年

作者： Zhang, Jiayi Zhang, Jing Björnson, Emil Ai, Bo The School of Electronic and Information Engineering Beijing Jiaotong University Beijing100044 China The Frontiers Science Center for Smart High-Speed Railway System Beijing Jiaotong University Beijing100044 China The Department of Electrical Engineering Linköping University Linköping Sweden The Department of Computer Science KTH Royal Institute of Technology Kista Sweden The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China The Frontiers Science Center for Smart High-Speed Railway System Henan Joint International Research Laboratory of Intelligent Networking and Data Analysis Zhengzhou University Zhengzhou450001 China Research Center of Networks and Communications Peng Cheng Laboratory Shenzhen China

Cell-free massive multiple-input multiple-output (MIMO) provides more uniform spectral efficiency (SE) for users (UEs) than cellular technology. The main challenge to achieve the benefits of cell-free massive MIMO is to realize signal processing in a scalable way. In this paper, we consider scalable full-pilot zero-forcing (FZF), partial FZF (PFZF), protective weak PFZF (PWPFZF), and local regularized ZF (LRZF) combining by exploiting channel statistics. We derive closed-form expressions of the uplink SE for FZF, PFZF, and PWPFZF combining with large-scale fading decoding over independent Rayleigh fading channels, taking channel estimation errors and pilot contamination into account. Moreover, we investigate the impact of the number of pilot sequences, antennas per AP, and APs on the performance. Numerical results show that LRZF provides the highest SE. However, PWPFZF is preferable when the number of pilot sequences is large and the number of antennas per AP is small. The reason is that PWPFZF has lower computational complexity and the SE expression can be computed in closed-form. Furthermore, we investigate the performance of PWPFZF combining with fractional power control and the numerical results show that it improves the performance of weak UEs and realizes uniformly good service for all UEs in a scalable fashion. Copyright © 2022, The Authors. All rights reserved.

关键词： Power control

Is the Skip Connection Provable to Reform the Neural Network Loss Landscape?

学校读者我要写书评

暂无评论

arXiv 2020年

作者： Wang, Lifu Shen, Bo Zhao, Ning Zhang, Zhiyuan Department of Electronic and Information Engineering Beijing Jiaotong University Beijing China Key Laboratory of Communication and Information Systems Beijing Municipal Commission of Education Beijing Jiaotong University Beijing China Department of Electronic and Information Engineering Beijing Jiaotong University Beijing China State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China

The residual network is now one of the most effective structures in deep learning, which utilizes the skip connections to "guarantee" the performance will not get worse. However, the non-convexity of the neural network makes it unclear whether the skip connections do provably improve the learning ability since the nonlinearity may create many local minima. In some previous works [Freeman and Bruna, 2016], it is shown that despite the non-convexity, the loss landscape of the two-layer ReLU network has good properties when the number m of hidden nodes is very large. In this paper, we follow this line to study the topology (sub-level sets) of the loss landscape of deep ReLU neural networks with a skip connection and theoretically prove that the skip connection network inherits the good properties of the two-layer network and skip connections can help to control the connectedness of the sub-level sets, such that any local minima worse than the global minima of some two-layer ReLU network will be very "shallow". The "depth" of these local minima are at most O(m(η−1)/n), where n is the input dimension, η Copyright © 2020, The Authors. All rights reserved.

关键词： Network layers