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Autonomous Vehicle Platoons In Urban Road Networks:A Joint distributed Reinforcement Learning and Model Predictive Control Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 141-156页

作者： Luigi d’Alfonso Francesco Giannini Giuseppe Franzè Giuseppe Fedele Francesco Pupo Giancarlo Fortino IEEE the department of Computer Engineering ModelingElectronics and SystemsUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy the department of Mechanical Engineering Energy Engineering and ManagementUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy

In this paper, platoons of autonomous vehicles operating in urban road networks are considered. From a methodological point of view, the problem of interest consists of formally characterizing vehicle state trajectory tubes by means of routing decisions complying with traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of two methodologies: deep reinforcement learning and model predictive control. On one hand, the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data at each road junction. On the other hand, a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle. Such tasks are here combined into a single framework:the deep reinforcement learning output(action) is translated into a set-point to be tracked by the model predictive controller;conversely, the current vehicle position, resulting from the application of the control move, is exploited by the deep reinforcement learning unit for improving its reliability. The main novelty of the proposed solution lies in its hybrid nature: on one hand it fully exploits deep reinforcement learning capabilities for decisionmaking purposes;on the other hand, time-varying hard constraints are always satisfied during the dynamical platoon evolution imposed by the computed routing decisions. To efficiently evaluate the performance of the proposed control architecture, a co-design procedure, involving the SUMO and MATLAB platforms, is implemented so that complex operating environments can be used, and the information coming from road maps(links,junctions, obstacles, semaphores, etc.) and vehicle state trajectories can be shared and exchanged. Finally by considering as operating scenario a real entire city block and a platoon of eleven vehicles described by double-integrator models, several simulations have been performed with the a

关键词： distributed model predictive control distributed reinforcement learning routing decisions urban road networks

Small molecules to target tau amyloid aggregation

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Neural Regeneration Research 2024年第3期19卷 509-511页

作者： Zoe Manglano-Artuñedo Samuel Peña-díaz Salvador Ventura Institut de Biotecnologia i Biomedicina Universitat Autònoma de BarcelonaBellaterraSpain

Protein aggregation has been linked with many neurodegenerative diseases,such as Alzheimer’s disease(Ad)or Parkinson’s *** belongs to a group of heterogeneous and incurable neurodegenerative disorders collectively known as *** comprise frontotemporal dementia,Pick’s disease,or corticobasal degeneration,among *** symptomatology varies with the specific tau protein variant involved and the affected brain region or cell ***,they share a common neuropathological hallmark-the formation of proteinaceous deposits named neurofibrillary *** tangles,primarily composed of aggregated tau(Zhang et al.,2022),disrupt normal neuronal functions,leading to cell death and cognitive decline.

关键词： tau degeneration aggregation

A Review of State-of-the-art Flexible Power Point Tracking Algorithms in Photovoltaic Systems for Grid Support:Classification and Application

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 1-21页

作者： Mina Haghighat Mehdi Niroomand Hossein dehghani Tafti Christopher d.Townsend Tyrone Fernando the department of Electrical Engineering University of IsfahanIsfahanIran the department of Electrical Electronic and Computer EngineeringUniversity of Western AustraliaCrawley WA 6009Australia

To maximize conversion efficiency,photovoltaic(PV)systems generally operate in the maximum power point tracking(MPPT)***,due to the increasing penetra tion level of PV systems,there is a need for more developed control functions in terms of frequency support services and voltage control to maintain the reliability and stability of the power ***,flexible active power control is a manda tory task for grid-connected PV systems to meet part of the grid ***,a significant number of flexible pow er point tracking(FPPT)algorithms have been introduced in the existing *** purpose of such algorithms is to real ize a cost-effective method to provide grid support functional ities while minimizing the reliance on energy storage *** paper provides a comprehensive overview of grid support functionalities that can be obtained with the FPPT control of PV systems such as frequency support and volt-var *** of these grid support functionalities necessitates PV sys tems to operate under one of the three control strategies,which can be provided with FPPT *** three control strate gies are classified as:①constant power generation control(CP GC),②power reserve control(PRC),and③power ramp rate control(PRRC).A detailed discussion on available FPPT algo rithms for each control strategy is also *** paper can serve as a comprehensive review of the state-of-the-art FPPT algorithms that can equip PV systems with various grid support functionalities.

关键词： Maximum power point tracking(MPPT) flexi ble power point tracking(FPPT) power reserve control(PRC) power ramp rate control(PRRC) low voltage ride-through(LVRT) constant power generation(CPG)

Prescribed-Time Nash Equilibrium Seeking for Pursuit-Evasion Game

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1518-1520页

作者： Lei Xue Jianfeng Ye Yongbao Wu Jian Liu d.C.Wunsch Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationNanjing 210096 School of Automation Southeast UniversityNanjing 210096China department of Electrical and Computer Engineering Missouri University of Science and TechnologyRollaMO 65409 USA IEEE

dear Editor,This letter is concerned with prescribed-time Nash equilibrium(PTNE)seeking problem in a pursuit-evasion game(PEG)involving agents with second-order *** order to achieve the prior-given and user-defined convergence time for the PEG,a PTNE seeking algorithm has been developed to facilitate collaboration among multiple pursuers for capturing the evader without the need for any global ***,it is theoretically proved that the prescribedtime convergence of the designed algorithm for achieving Nash equilibrium of ***,the effectiveness of the PTNE method was validated by numerical simulation results.A PEG consists of two groups of agents:evaders and *** pursuers aim to capture the evaders through cooperative efforts,while the evaders strive to evade *** is a classic noncooperative *** has attracted plenty of attention due to its wide application scenarios,such as smart grids[1],formation control[2],[3],and spacecraft rendezvous[4].It is noteworthy that most previous research on seeking the Nash equilibrium of the game,where no agent has an incentive to change its actions,has focused on asymptotic and exponential convergence[5]-[7].

关键词： seeking prescribed convergence

Refractive outcomes after V4c Toric collamer lens implantation over 1y of follow-up

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1322-1330页

作者： Humberto Carreras-díaz Josefina Reñones de Abajo María del Rosario Carreras-díaz Amalia Lorente-Velázquez Vithas Eurocanarias Las Palmas de Gran Canaria 35004Spain University Hospital of Girona doctor Josep Trueta Gerona 17007Spain departament of Optometry and Vision Faculty of Optics and OptometryComplutense University of MadridMadrid 28040Spain

AIM:To evaluate refractive outcomes and corneal astigmatism changes after Toric implantable collamer lens with a central port(V4c T-ICL)implantation over 1y of ***:A retrospective study was performed including 50 eyes of 50 patients that underwent V4c T-ICL ***(UdVA)and corrected(CdVA)distance visual acuities,refraction,refractive and corneal astigmatism changes and corneal coupling correction were evaluated preoperatively,1 and 12mo *** analysis was used for astigmatism *** of adjustment(CAdj)was calculated for corneal coupling ***:The mean UdVA achieved was 0.03 logMAR at 1mo and remained unchanged throughout the whole follow-up(P=0.193).At the last visit,84%of the eyes achieved a CdVA of 0.00 logMAR or *** spherical equivalent refraction(SEQ),96%of eyes were ranges of±1.00 d and 84%of them within±0.50 ***,94%of eyes had a remaining refractive cylinder within±1.00 d and 78%of them within±0.50 ***,SEQ and refractive cylinder,remain stable over the postoperative follow-up(P=1.000 and P=0.660,respectively).In terms of surgically induced astigmatism(SIA),no statistically significant differences were found over the follow-up(P=0.102)and under correction was found with a correction index lower than the unit at each visit.A keratometric astigmatism induced of 0.59±0.53(vector mean:0.26×73º)d was reached at the last *** significant changes in terms of corneal astigmatism orientation were reported over post-surgery visits(P=0.129 and P=0.097 at 1 and 12mo respectively).No clinical significance was found for CAdj on with-the-rule *** postoperative complications resulting from the surgery were ***:Refractive outcomes suggest that the V4c T-ICL implantation for correction of myopic astigmatism was satisfactory in terms of effectiveness,safety,and stability during 1y of *** astigmatism induced by the incision around 0.5 d is achieved

关键词： V4c Toric collamer lens corneal astigmatism surgically induced astigmatism corneal coupling

The effect of Common Cuckoo parasitism on the annual productivity of a host population

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Avian Research 2024年第2期15卷 287-291页

作者： Alfred Trnka department of Biology University of TrnavaPriemyselna 491843TrnavaSlovakia

Avian interspecific brood parasitism is an excellent system for studying coevolutionary processes in nature because brood parasites directly affect host reproductive *** research on avian brood parasitism has,therefore,focused primarily on specific host anti-parasite behaviours and parasite ***,the population-level consequences of brood parasitism for host species are poorly *** study investigated the effect of Common Cuckoo(Cuculus canorus)parasitism on the productivity of a local population of the Great Reed Warbler(Acrocephalus arundinaceus)host in south-western Slovakia.A total of 495 females nesting at the studied site successfully fledged 1321 of their own young and 63 young of the Common Cuckoo over the course of 15 years(2008-2022),and the annual rate of successful parasitism ranged from 18% to 44% over this *** predicted,higher rates of successful cuckoo parasitism significantly reduced the annual productivity of the local Great Reed Warbler population,and its contribution to decreased host reproductive success was at about the same rate as overall nest failure caused by predation and other environmental *** a heavily parasitized population was probably maintained by immigrants from other populations and density-dependent selection,which is also consistent with source-sink ***,further long-term studies monitoring parasitized populations are required to confirm these findings.

关键词： Acrocephalus arundinaceus Cuculus canorus Great Reed Warbler Population growth Reproductive success

Performance analysis of jig for coal cleaning using 3d response surface methodology

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International Journal of Mining Science and Technology 2017年第2期27卷 333-337页

作者： Kumar Shravan venugopal R. department of Fuel and Mineral Engineering Indian Institute of Technology(ISM)Dhanbad826004India

Beneficiation of coal of -4.76 mm + 3 mm size fraction was investigated in a laboratory model denver *** variables were studied to analyze their effect on the performance of jig in terms of yield and ash content of clean coal. Three-factor three-level Box-Behnken design of experiments with response surface methodology(RSM) was employed to understand the performance behavior of jig. From the study, the bed height was found to be the most significant parameter affecting the yield and ash content of clean coal. It was possible to reduce the ash content from 24.32% in feed to an ash content of 16.55% in clean coal at 2 L/min water flow rate and 10 min jigging time. Influence of operating variables of the jig on responses was presented and discussed in 3d surface plots. The developed model was found to be significant within the range of parameters under investigation with correlation of co-efficient values as 0.99(yield) and 0.98(ash).

关键词： Coal beneficiation Jigging Bed height 3d-RSM Box-Behnken

Enantioselective iridium-catalyzed allylic substitution with a Reformatsky reagent: direct construction of β-stereogenic homoallylic esters

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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： debasis Pal Kirana d.Veeranna Yuk Fai Wong P.Andrew Evans department of Chemistry Queen's University Xiangya School of Pharmaceutical Sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.James J.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted