检索结果-内蒙古大学图书馆

arXiv 2021年

作者： Ramos, Guilherme Silvestre, Daniel Silvestre, Carlos The Department of Electrical and Computer Engineering Faculty of Engineering University of Porto Portugal NOVA University of Lisbon The Institute for Systems and Robotics Instituto Superior Técnico University of Lisbon Lisbon1049-001 Portugal The Dep. of Electrical and Computer Engineering The Faculty of Science and Technology The University of Macau China Instituto Superior Técnico Technical University of Lisbon Lisbon Portugal

We tackle the problem of a set of agents achieving resilient consensus in the presence of attacked agents. We present a discrete-time reputation-based consensus algorithm for synchronous and asynchronous networks by developing a local strategy where, at each time, each agent assigns a reputation (between zero and one) to each neighbor. The reputation is then used to weigh the neighbors' values in the update of its state. Under mild assumptions, we show that: (i) the proposed method converges exponentially to the consensus of the regular agents;(ii) if a regular agent identifies a neighbor as an attacked node, then it is indeed an attacked node;(iii) if the consensus value of the normal nodes differs from that of any of the attacked nodes' values, then the reputation that a regular agent assigns to the attacked neighbors goes to zero. Further, we extend our method to achieve resilience in the scenarios where there are noisy nodes, dynamic networks and stochastic node selection. Finally, we illustrate our algorithm with several examples, and we delineate some attacking scenarios that can be dealt by the current proposal but not by the state-of-the-art approaches. Copyright © 2021, The Authors. All rights reserved.

关键词： Stochastic systems

来源：评论

学校读者我要写书评

暂无评论

Gaussian Process Gradient Maps for Loop-Closure Detection in Unstructured Planetary Environments

arXiv

引用

arXiv 2020年

作者： Le Gentil, Cedric Vayugundla, Mallikarjuna Giubilato, Riccardo Stürzl, Wolfgang Vidal-Calleja, Teresa Triebel, Rudolph Centre for Autonomous Systems Faculty of Engineering and IT University of Technology Sydney Australia Institute of Robotics and Mechatronics Germany Department of Computer Science Germany

The ability to recognize previously mapped locations is an essential feature for autonomous systems. Unstructured planetary-like environments pose a major challenge to these systems due to the similarity of the terrain. As a result, the ambiguity of the visual appearance makes state-of-the-art visual place recognition approaches less effective than in urban or man-made environments. This paper presents a method to solve the loop closure problem using only spatial information. The key idea is to use a novel continuous and probabilistic representations of terrain elevation maps. Given 3D point clouds of the environment, the proposed approach exploits Gaussian Process (GP) regression with linear operators to generate continuous gradient maps of the terrain elevation information. Traditional image registration techniques are then used to search for potential matches. Loop closures are verified by leveraging both the spatial characteristic of the elevation maps (SE(2) registration) and the probabilistic nature of the GP representation. A submap-based localization and mapping framework is used to demonstrate the validity of the proposed approach. The performance of this pipeline is evaluated and benchmarked using real data from a rover that is equipped with a stereo camera and navigates in challenging, unstructured planetary-like environments in Morocco and on Mt. Etna. Copyright © 2020, The Authors. All rights reserved.

关键词： Gaussian noise (electronic)

来源：评论

学校读者我要写书评

暂无评论

Compressive and energy absorption properties of titanium hybrid lattice structures for bioimplant applications fabricated via LPBF

引用

Materials and Design 2025年 254卷

作者： Karmiris-Obratański, Panagiotis Georgakopoulos-Soares, Ilias Cichocki, Kamil Lisiecka-Graca, Paulina Papazoglou, Emmanouil L. Advanced Manufacturing Laboratory Department of Manufacturing Systems Faculty of Mechanical Engineering and Robotics AGH University of Krakow Krakow Poland School of Chemical Engineering Department of Materials Science and Engineering National Technical University of Athens Heroon Polytechniou 9 Athens15780 Greece Institute for Personalized Medicine Department of Biochemistry and Molecular Biology The Pennsylvania State University College of Medicine HersheyPA United States Faculty of Metals Engineering and Computer Science AGH University of Krakow Adama Mickiewicza Ave. 30 Kraków30-059 Poland School of Mechanical Engineering Section of Manufacturing Technology National Technical University of Athens Heroon Polytechniou 9 Athens15780 Greece

The compressive properties of lattice structures are strongly influenced by lattice design, density, material, and manufacturing method. Recent advancements in manufacturing, particularly Additive Manufacturing, have enabled the fabrication of complex lattice structures from advanced materials. Building on this progress, the present study investigates the compressive properties and energy absorption capabilities of four distinct lattice structures at three relative densities (20 %, 30 %, and 40 %), specifically tailored for implant applications. The lattices, fabricated from Ti6Al4V ELI alloy using the Laser Powder Bed Fusion (LPBF) method, include a hybrid Fluorite-BCC lattice, a SplitP TPMS skeletal lattice, a stochastic Voronoi lattice, and a hybrid Voronoi-TPMS Gyroid lattice. Compressive properties, including the Elastic Modulus of Compression (EMC), Compressive Yield Strength, and Ultimate Compressive Strength, were systematically analyzed alongside energy absorption capabilities. The Gibson-Ashby model was employed to quantify the relationship between compressive properties and relative density. Additionally, Digital Image Correlation and high-resolution imaging during compression tests provided detailed insights into deformation mechanisms and collapse behavior. The findings offer valuable insights into the compressive performance of these novel hybrid lattices, highlighting their potential applicability in bioimplant applications, with the Fluorite-BCC lattice exhibits the highest EMC and the Fluorite-BCC and SplitP lattices exhibit higher energy absorption capabilities. © 2025 The Author(s)

关键词： Machinability

来源：评论

学校读者我要写书评

暂无评论

A Data logger for educational purposes of a laboratory chemical reactor: an IoT approach

A Data logger for educational purposes of a laboratory chemi...

引用

Electrical, computer, Communications and Mechatronics Engineering (ICECCME), International Conference on

作者： José Lima Thadeu Brito Olga Ferreira Maria J. Afonso Vítor H. Pinto José A. Carvalho Paulo Costa Research Centre in Digitalization and Intelligent Robotics (CeDRI) Instituto Politécnico de Bragança Bragança Portugal Laboratório Para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC) Instituto Politécnico de Bragança Bragança Portugal Centre for Robotic in Industry and Intelligent Systems Institute for Systems and Computer Engineering Technology and Science (INESC-TEC) Porto Portugal CeDRI SusTEC INESC-TEC Faculty of Engineering of University of Porto (FEUP) Porto Portugal SusTEC ESTiG Instituto Politécnico de Bragança Bragança Portugal ARISE & ECE Dept. Research Center for Systems and Technologies (SYSTEC) FEUP CeDRI SusTEC INESC-TEC FEUP

This paper presents the development of an acquisition system and data logger from an existing set of three continuous stirred-tank reactors in series. The reactors are currently used in chemical engineering educational laboratories to perform kinetic and tracer experiments. In this sense, to accomplish the store data process, the volumetric flow rate and the concentration of tracer, reactants and/or products of the reaction must be acquired as a function of time. In the original experimental setup, only the signal conditioning system was operational, while the acquisition, visualization, and control systems were obsolete and damaged. Thus, a new system composed of an interface and real-time acquisition data is proposed alongside preserving the main reactor structure. A graphical user interface and the automation of the various actuators were developed based on worldwide usage and low cost, respectively. This system, based on a common 8-bit microcontroller and an application developed in Lazarus, allows the storage of the acquired data in a time-series database. In this way, students can analyze the results later or in real time. Moreover, remote access allows controlling the reactor and getting data by the Internet of Things (IoT) resources. Additionally, the proposed system using IoT allows data to be shared with the community as a dataset.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Preface

Lecture Notes in Networks and Systems

引用

Lecture Notes in Networks and systems 2024年 1076 LNNS卷 v-vii页

作者： Biele, Cezary Kacprzyk, Janusz Kopeć, Wieslaw Możaryn, Jakub Owsiński, Jan W. Romanowski, Andrzej Sikorski, Marcin National Information Processing Institute Warszaw Poland Polish Academy of Sciences Systems Research Institute Warsaw Poland Polish-Japanese Academy of Information Technology Warsaw Poland Institute of Automatic Control and Robotics Faculty of Mechatronics Warsaw University of Technology Warsaw Poland Institute of Applied Computer Science Faculty of Electrical Electronic Computer and Control Engineering Lódż University of Technology LODZ Poland Department of Applied Informatics in Management Faculty of Management and Economics Gdańsk University of Technology Gdańsk Poland

来源：评论

学校读者我要写书评

暂无评论

Automated Controller Placement for Software-Defined Networks to Resist DDoS Attacks

引用

computers, Materials & Continua 2021年第9期68卷 3147-3165页

作者： Muhammad Reazul Haque Saw Chin Tan Zulfadzli Yusoff Kashif Nisar Lee Ching Kwang Rizaludin Kaspin Bhawani Shankar Chowdhry Rajkumar Buyya Satya Prasad Majumder Manoj Gupta Shuaib Memon Faculty of Computing&Informatics Multimedia UniversityPersiaran MultimediaCyberjaya63100SelangorMalaysia Faculty of Engineering Multimedia UniversityPersiaran MultimediaCyberjaya63100SelangorMalaysia Faculty of Computing and Informatics University Malaysia SabahJalan UMSKota Kinabalu Sabah88400Malaysia Telekom Malaysia Research&Development TM Innovation CentreCyberjaya63000SelangorMalaysia National Center of Robotics and Automation Mehran University of Engineering&TechnologyJamshoroPakistan Department of Computer Science and Engineering Hanyang UniversitySeoul04763South Korea School of Electrical and Electronic Engineering Nanyang Technological University639798Singapore Cloud Computing and Distributed Systems Laboratory The University of MelbourneMelbourneVIC 3053Australia Department of Electrical and Electronic Engineering Bangladesh University of Engineering and Technology(BUET)Dhaka1205Bangladesh Department of Electronics and Communication Engineering JECRC UniversityVidhaniJaipur303905India Auckland Institute of Studies Mt AlbertAucklandNew Zealand

In software-defined networks(SDNs),controller placement is a critical factor in the design and planning for the future Internet of Things(IoT),telecommunication,and satellite communication *** research has concentrated largely on factors such as reliability,latency,controller capacity,propagation delay,and energy ***,SDNs are vulnerable to distributed denial of service(DDoS)attacks that interfere with legitimate use of the *** ever-increasing frequency of DDoS attacks has made it necessary to consider them in network design,especially in critical applications such as military,health care,and financial services networks requiring high *** propose a mathematical model for planning the deployment of SDN smart backup controllers(SBCs)to preserve service in the presence of DDoS *** a number of input parameters,our model has two distinct ***,it determines the optimal number of primary controllers to place at specific locations or nodes under normal operating ***,it recommends an optimal number of smart backup controllers for use with different levels of DDoS *** goal of the model is to improve resistance to DDoS attacks while optimizing the overall cost based on the *** simulated results demonstrate that the model is useful in planning for SDN reliability in the presence of DDoS attacks while managing the overall cost.

关键词： SDN automated controller placement SBC ILP DDoS attack

来源：评论

学校读者我要写书评

暂无评论

A Non-Parametric LPV Approach to the Indentification of Linear Periodic systems ⁎

引用

IFAC-PapersOnLine 2021年第8期54卷 13-19页

作者： Paulo Lopes dos Santos T-P Azevedo Perdicoúlis INESC TEC - Institute for Systems and Computer Engineering Technology and Science and FEUP - Faculty of Engineering University of Porto Rua Dr Roberto Frias s/n 4200-464 Porto Portugal Universidade de Trás-os-Montes e Alto Douro Vila Real and Instituto de Sistemas e Robótica (ISR) Coimbra both in Portugal

A non-parametric identification algorithm is proposed to identify Linear time Periodic (LTP) systems. The period is unknown and can be any real positive number. The system is modelled as an ARX Linear Parameter Varying (LPV) system with a virtual scheduling signal consisting of two orthogonal sinusoids (a sine and a cosine) with a period equal to the system period. Hence, the system parameters are polynomial functions of the scheduling vector. As these polynomials may have infinite degree, a non-parametric model is adopted to describe the LPV system. This model is identified by a Gaussian Process Regression (GPR) algorithm where the system period is a hyperparameter. The performance of the proposed identification algorithm is illustrated through the identification of a simulated LTP continuous system described by a state-space model. The ARX-LTP discrete-time model estimated in the noiseless case was taken as the true model.

关键词： System Identification LTP systems LPV systems Arx Gaussian Process Regression Kernel

来源：评论

学校读者我要写书评

暂无评论

Accurate, interpretable, and fast animation: An iterative, sparse, and nonconvex approach

arXiv

引用

arXiv 2021年

作者： Racković, Stevo Soares, Cláudia Jakovetić, Dušan Desnica, Zoranka Institute for Systems and Robotics Instituto Superior Técnico Lisbon1049-001 Portugal Computer Science Department NOVA School of Science and Technology Caparica2825-149 Portugal Department of Mathematics Faculty of Sciences University of Novi Sad Novi Sad21000 Serbia 3Lateral Animation Studio Epic Games Company

Digital human animation relies on high-quality 3D models of the human face-rigs. A face rig must be accurate and, at the same time, fast to compute. One of the most common rigging models is the blendshape model. We propose a novel algorithm for solving the nonconvex inverse rig problem in facial animation. Our approach is model-based, but in contrast with previous model-based approaches, we use a quadratic instead of the linear approximation to the higher order rig model. This increases the accuracy of the solution by 8% (0:26mm) on average and, confirmed by the empirical results, increases the sparsity of the resulting parameter vector-an important feature for interpretability by animation artists. The proposed solution is based on a Levenberg-Marquardt (LM) algorithm, applied to a nonconvex constrained problem with sparsity regularization. In order to reduce the complexity of the iterates, a paradigm of Majorization Minimization (MM) is further invoked, which leads to an easy to solve problem that is separable in the parameters at each algorithm iteration. The algorithm is evaluated on a number of animation datasets, proprietary and open-source, and the results indicate the superiority of our method compared to the standard approach based on the linear rig approximation. Although our algorithm targets the specific problem, it might have additional signal processing applications. © 2021, CC BY-NC-SA.

关键词： Animation

来源：评论

学校读者我要写书评

暂无评论

A realistic simulation environment as a teaching aid in educational robotics

A realistic simulation environment as a teaching aid in educ...

引用

IEEE Latin American robotics Symposium, LARS

作者： José Lima Rebeca B. Kalbermatter João Braun Thadeu Brito Guido Berger Paulo Costa Research Centre in Digitalization and Intelligent Robotics (CeDRI) Instituto Politécnico de Bragança (IPB) Bragança Portugal Laboratório para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC) Instituto Politécnico de Bragança (IPB) Bragança Portugal Centre for Robotic in Industry and Intelligent Systems Institute for Systems and Computer Engineering Technology and Science (INESC-TEC) Porto Portugal Faculdade de Engenharia Universidade do Porto Porto Portugal Universidade de Trás-os-Montes e Alto Douro Vila Real Portugal

ISBN: (数字)9781665462808

ISBN: (纸本)9781665462815

The experimental component is an essential method in Engineering education. Sometimes the availability of laboratories and components is compromised, and the COVID-19 pandemic worsened the situation. Resorting to an accurate simulation seems to help this process by allowing students to develop the work, program, test, and validate it. Moreover, it lowers the development time and cost of the prototyping stages of a robotics project. As a multidisciplinary area, robotics requires simulation environments with essential characteristics, such as dynamics, connection to hardware (embedded systems), and other applications. Thus, this paper presents the Simulation environment of SimTwo, emphasizing previous publications with models of sensors, actuators, and simulation scenes. The simulator can be used for free, and the source code is available to the community. Proposed scenes and examples can inspire the development of other simulation scenes to be used in electrical and mechanical Engineering projects.

关键词： Mechanical sensors Embedded systems Pandemics Source coding Laboratories Sensor phenomena and characterization Robot sensing systems

来源：评论

学校读者我要写书评

暂无评论

Modeling of adsorptive removal of azithromycin from aquatic media by CoFe₂O₄_/NiO anchored microalgae-derived nitrogen-doped porous activated carbon adsorbent and colorimetric quantifying of azithromycin in pharmaceutical products

引用

Chemosphere 2023年第1期329卷 138635页

作者： Ameen, Fuad Mostafazadeh, Reza Hamidian, Yasamin Erk, Nevin Sanati, Afsaneh L. Karaman, Ceren Ayati, Ali Department of Botany and Microbiology College of Science King Saud University Riyadh 11451 Saudi Arabia Ankara University Faculty of Pharmacy Department of Analytical Chemistry Ankara 06560 Turkey Institute of Systems and Robotics Department of Electrical and Computer Engineering University of Coimbra Polo II Coimbra 3030-290 Portugal Akdeniz University Vocational School of Technical Sciences Department of Electricity and Energy Antalya 07070 Turkey ChemBio Cluster ITMO University Lomonosova Street 9 Saint Petersburg 191002 Russian Federation

Herein, it was aimed to optimize the removal process of Azithromycin (Azi) from the aquatic environment via CoFe2O4/NiO nanoparticles anchored onto the microalgae-derived nitrogen-doped porous activated carbon (N-PAC)... 详细信息

Herein, it was aimed to optimize the removal process of Azithromycin (Azi) from the aquatic environment via CoFe₂O₄_/NiO nanoparticles anchored onto the microalgae-derived nitrogen-doped porous activated carbon (N-PAC), besides developing a colorimetric method for the swift monitoring of Azi in pharmaceutical products. In this study, the Spirulina platensis (Sp) was used as a biomass resource for fabricating CoFe₂O₄/NiO@N-PAC adsorbent. The pores of N-PAC mainly entail mesoporous structures with a mean pore diameter of 21.546 nm and total cavity volume (V_total) of 0.033578 cm³. g⁻¹. The adsorption studies offered that 98.5% of Azi in aqueous media could remove by CoFe₂O₄/NiO@N-PAC. For the cyclic stability analysis, the adsorbent was separated magnetically and assessed at the end of five adsorption-desorption cycles with a negligible decrease in adsorption. The kinetic modeling revealed that the adsorption of Azi onto the CoFe₂O₄/NiO@N-PAC was well-fitted to the second-order reaction kinetics, and the highest adsorption capacity was found as 2000 mg. g⁻¹ at 25 °C based on the Langmuir adsorption isotherm model at 0.8 g. L⁻¹ adsorbent concentration. The Freundlich isotherm model had the best agreement with the experimental data. Thermodynamic modeling indicated the spontaneous and exothermic nature of the adsorption process. Moreover, the effects of pH, temperature, and operating time were also optimized in the colorimetric Azi detection. The blue ion-pair complexes between Azi and Coomassie Brilliant Blue G-250 (CBBG-250) reagent followed Beer's law at wavelengths of 640 nm in the concentration range of 1.0 μM to 1.0 mM with a 0.94 μM limit of detection (LOD). In addition, the selectivity of Azi determination was verified in presence of various species. Furthermore, the applicability of CBBG-250 dye for quantifying

关键词： Adsorption Adsorption modeling Azithromycin Biomass-derived activated carbon Spectrophotometry Spirulina platensis

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：