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Distributed formation control of manipulators' end-effector with internal model-based disturbance rejection

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arXiv 2021年

作者： Wu, Haiwen Jayawardhana, Bayu de Marina, Hector Garcia Xu, Dabo Engineering and Technology Institute Groningen Faculty of Science and Engineering University of Groningen Groningen9747 AG Netherlands Department of Computer Architecture and Automatic Control Faculty of Physics Universidad Complutense de Madrid Madrid28040 Spain The School of Automation Nanjing University of Science and Technology Nanjing210094 China

This paper addresses the problem of end-effector formation control for manipulators that are subjected to external disturbances: input disturbance torques and disturbance forces at each end-effector. The disturbances are assumed to be non-vanishing and are superposition of finite number of sinusoidal and step signals. The formation control objective is achieved by assigning virtual springs between end-effectors, by adding damping terms at joints, and by incorporating internal model-based dynamic compensators to counteract the effect of the disturbances;all of which presents a clear physical interpretation of the proposed approach. Simulation results are presented to illustrate the effectiveness of the proposed approach. © 2021, CC BY.

关键词： End effectors

Network Realization Functions for Optimal Distributed control

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arXiv 2021年

作者： Sabau, Şerban Sperila, Andrei Oara, Cristian Jadbabaie, Ali Electrical and Computer Engineering Department Stevens Institute of Technology HobokenNJ07030 United States Faculty of Automatic Control and Computers "Politehnica" University of Bucharest Sector 6 060042 Romania CambridgeMA02139 United States

In this paper, we discuss a distributed control architecture, aimed at networks with linear and time-invariant dynamics, which is amenable to convex formulations for controller design. The proposed approach is well suited for large scale systems, since the resulting feedback schemes completely avoid the exchange of internal states, i.e., plant or controller states, among sub-controllers. Additionally, we provide state-space formulas for these sub-controllers, able to be implemented in a distributed manner. © 2021, CC BY.

关键词： Large scale systems

TextBenDS: A generic textual data benchmark for distributed systems

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arXiv 2021年

作者： Truicǎ, Ciprian-Octavian Apostol, Elena Darmont, Jérôme Assent, Ira Computer Science and Engineering Department Faculty of Automatic Control and Computers University Politehnica of Bucharest Bucharest Romania Department of Computer Science Aarhus University Aarhus Denmark Université de Lyon ERIC Lyon 2 EA 3083 France DIGIT Department of Computer Science Aarhus University Denmark

Extracting top-k keywords and documents using weighting schemes are popular techniques employed in text mining and machine learning for different analysis and retrieval tasks. The weights are usually computed in the data preprocessing step, as they are costly to update and keep track of all the modifications performed on the dataset. Furthermore, computation errors are introduced when analyzing only subsets of the dataset. Therefore, in a Big Data context, it is crucial to lower the runtime of computing weighting schemes, without hindering the analysis process and the accuracy of the machine learning algorithms. To address this requirement for the task of top-k keywords and documents, it is customary to design benchmarks that compare weighting schemes within various configurations of distributed frameworks and database management systems. Thus, we propose a generic document-oriented benchmark for storing textual data and constructing weighting schemes (TextBenDS). Our benchmark offers a generic data model designed with a multidimensional approach for storing text documents. We also propose using aggregation queries with various complexities and selectivities for constructing term weighting schemes, that are utilized in extracting top-k keywords and documents. We evaluate the computing performance of the queries on several distributed environments set within the Apache Hadoop ecosystem. Our experimental results provide interesting insights. As an example, MongoDB proves to have the best overall performance, while Spark's execution time remains almost the same, regardless of the weighting schemes. Copyright © 2021, The Authors. All rights reserved.

关键词： Machine learning

The evolution and challenges of modern Distributed control Systems

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The evolution and challenges of modern Distributed Control S...

International Symposium on Applied Computational Intelligence and Informatics ( SACI)

作者： Dănuț Adrian Poștovei Constantin Bulac Ion Triștiu Balduino Camachi Faculty of Power Engineering University Politehnica of Bucharest Bucharest Romania Faculty of Automatic Control and Computer Science University Politehnica of Bucharest Bucharest Romania

ISBN: (数字)9781728173771

ISBN: (纸本)9781728173788

This paper presents the evolution and development trends of the distributed control systems (DCS) implemented in the Electrical Power Systems, highlighting the impact of the modern versus traditional DCS systems. The principles of the modern DCS systems presented in this paper can be found implemented in Romania in the Transmission and Distribution energy sector, implemented by the Romanian Transmission and System Operator CNTEE Transelectrica SA and, as well as the electricity distribution operators like Electrica, EoN and CEZ.

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Setting up a Distributed control System Laboratory

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Setting up a Distributed Control System Laboratory

International Conference and Exposition on Electrical and Power engineering (EPE)

作者： Dănuţ Adrian Poştovei Constantin Bulac Ion Triştiu Balduino Camachi Faculty of Power Engineering University Politehnica of Bucharest Bucharest Romania Faculty of Automatic Control and Computer Science University Politehnica of Bucharest Bucharest Romania

ISBN: (数字)9781728181264

ISBN: (纸本)9781728181271

This paper presents a practical laboratory for student education purpose in Distributed control Systems, with focus on applications for high voltage transmission substations. The monitoring, control and protection part is realized with a software platform and IED devices manufactured by AREVA T&D France, while the primary equipment, like circuit breakers and disconnectors are simulated with latched relays. The system architecture and communication network are reproducing a real one usually used in transmission substations. The implementation of this laboratory, both through specific laboratory works and experiments, makes the theoretical part to be supported by a practical experience, resulting in future graduates with added value in the electric power industry.

关键词： Databases Substations Relays Tools Protocols Monitoring Hardware

A practical implementation of modern Distributed control Systems in Electric Power Substations

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A practical implementation of modern Distributed Control Sys...

International Conference on Electronics, computers and Artificial Intelligence (ECAI)

ISBN: (数字)9781728168432

ISBN: (纸本)9781728168449

This paper presents a practical implementation of a modern DCS in energy sector, applicable for electric power transmission and distributions substations. When dealing with aging infrastructure the reward from investing in modern automation solution can be substantial, with benefits such increasing productivity, cost savings, safety operations, scalable solution and a better integration in the modern IT facilities. The modern DCS systems evolved into a flexible and scalable automation solutions, which make them mandatory in the actual competitive energy business environment. Comparing to PLCs and traditional DCS, the modern DCS systems are designed to provide automation solution in a safe, reliable and cost-effectively manner. The main goal of this article is to present and suggest an optimal DCS design and functional solutions taking into consideration customer requirements, international and customer applicable norms, budget constraint, hardware and software limitations, integration of existing equipment, cybersecurity and low impact of the monitored and controlled process for extension and future growth. The principles presented in this paper can be found implemented in Romania mainly in the electric power transmission substations, owned by Romanian Transmission and System Operator CNTEE Transelectrica SA.

关键词： Substations Process control Monitoring Software Servers Automation IEC Standards

2D nanomaterials for realization of flexible and wearable gas sensors: A review

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Chemosphere 2024年 352卷 141234页

作者： Pawar, Krishna Kiran Kumar, Ashok Mirzaei, Ali Kumar, Mahesh Kim, Hyoun Woo Kim, Sang Sub Division of Materials Science and Engineering Hanyang University Seoul 04763 South Korea The Research Institute of Industrial Science Hanyang University Seoul 04763 South Korea School of Nanoscience and Technology Shivaji University Kolhapur 416004 India Department of Electrical Engineering Indian Institute of Technology Jodhpur 342030 India Department of Materials Science and Engineering Shiraz University of Technology Shiraz 715557-13876 Iran Department of Cybernetics Nanotechnology and Data Processing Faculty of Automatic Control Electronics and Computer Science Silesian University of Technology Akademicka 16 Gliwice 44-100 Poland Department of Materials Science and Engineering Inha University Incheon 22212 South Korea

Gas sensors are extensively employed for monitoring and detection of hazardous gases and vapors. Many of them are produced on rigid substrates, but flexible and wearable gas sensors are needed for intriguing usage including the internet of things (IoT) and medical devices. The materials with the greatest potential for the fabrication of flexible and wearable gas sensing devices are two-dimensional (2D) semiconducting nanomaterials, which consist of graphene and its substitutes, transition metal dichalcogenides, and MXenes. These types of materials have good mechanical flexibility, high charge carrier mobility, a large area of surface, an abundance of defects and dangling bonds, and, in certain instances adequate transparency and ease of synthesis. In this review, we have addressed the different 2D nonmaterial properties for gas sensing in the context of fabrication of flexible/wearable gas sensors. We have discussed the sensing performance of flexible/wearable gas sensors in various forms such as pristine, composite and noble metal decorated. We believe that content of this review paper is greatly useful for the researchers working in the research area of fabrication of flexible/wearable gas sensors. © 2024 Elsevier Ltd

关键词： 2D nanomaterials Flexible/wearable gas sensor Graphene MXenes Sensing mechanism TMDs Toxic gas

The forgotten document-oriented database management systems: An overview and benchmark of native XML DODBMSes in comparison with JSON DODBMSes

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arXiv 2021年

作者： Truică, Ciprian-Octavian Apostol, Elena-Simona Darmont, Jérôme Pedersen, Torben Bach Computer Science and Engineering Department Faculty of Automatic Control and Computers University Politehnica of Bucharest Romania Department of Computer Science Aarhus University Aarhus Denmark Université de Lyon ERIC UR 3083 Lyon 2 France Center for Data Intensive Systems Aalborg University Aalborg Denmark

In the current context of Big Data, a multitude of new NoSQL solutions for storing, managing, and extracting information and patterns from semi-structured data have been proposed and implemented. These solutions were developed to relieve the issue of rigid data structures present in relational databases, by introducing semi-structured and flexible schema design. As current data generated by different sources and devices, especially from IoT sensors and actuators, use either XML or JSON format, depending on the application, database technologies that store and query semi-structured data in XML format are needed. Thus, Native XML Databases, which were initially designed to manipulate XML data using standardized querying languages, i.e., XQuery and XPath, were rebranded as NoSQL Document-Oriented Databases Systems. Currently, the majority of these solutions have been replaced with the more modern JSON based Database Management Systems. However, we believe that XML-based solutions can still deliver performance in executing complex queries on heterogeneous collections. Unfortunately nowadays, research lacks a clear comparison of the scalability and performance for database technologies that store and query documents in XML versus the more modern JSON format. Moreover, to the best of our knowledge, there are no Big Data-compliant benchmarks for such database technologies. In this paper, we present a comparison for selected Document-Oriented Database Systems that either use the XML format to encode documents, i.e., BaseX, eXist-db, and Sedna, or the JSON format, i.e., MongoDB, CouchDB, and Couchbase. To underline the performance differences we also propose a benchmark that uses a heterogeneous complex schema on a large DBLP corpus. © 2021, CC BY.

关键词： XML

Combining Trajectory Data with Analytical Lyapunov Functions for Improved Region of Attraction Estimation

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arXiv 2021年

作者： Lugnani, Lucas Jones, Morgan Alberto, Luís F.C. Peet, Matthew Dotta, Daniel Faculty of Electrical and Computer Engineering University of Campinas Brazil The Department of Automatic Control and Systems Engineering University of Sheffield United Kingdom The São Carlos Engineering School University of São Paulo São Carlos Brazil The School for the Engineering of Matter Transport and Energy Arizona State University Tempe United States

The increasing uptake of inverter based resources (IBRs) has resulted in many new challenges for power system operators around the world. The high level of complexity of IBR generators makes accurate classical model-based stability analysis a difficult task. This paper proposes a novel methodology for solving the problem of estimating the Region of Attraction (ROA) of a nonlinear system by combining classical model based methods with modern data driven methods. Our method yields certifiable inner approximations of the ROA, typical to that of model based methods, but also harnesses trajectory data to yield an improved accurate ROA estimation. The method is carried out by using analytical Lyapunov functions, such as energy functions, in combination with data that is used to fit a converse Lyapunov function. Our methodology is independent of the function fitting method used. In this work, for implementation purposes, we use Bernstein polynomials to function fit. Several numerical examples of ROA estimation are provided, including the Single Machine Infinite Bus (SMIB) system, a three machine system and the Van-der-Pol system. Copyright © 2021, The Authors. All rights reserved.

关键词： Lyapunov functions