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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu Fu Nicola Baresi roberto Armellin Surrey Space Centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland Space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this *** key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA ***-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical *** Carlo simulations demonstrated that the baseline QSO of JAXA’s Martian Moons eXploration(MMX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

Estimating the frequency of traffic overloading on road bridges

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 776-796页

作者： roberto Ventura Benedetto Barabino Giulio Maternini Department of Civil EnvironmentalArchitectural Engineering and MathematicsUniversity of BresciaBrescia 25123Italy

Load limits,which appear to be routinely exceeded by trucks,occasionally result in road bridge ***,predicting failures is crucial for safeguarding road *** studies have largely focused on forecasting bridge failure event probability using the reliability analysis method,whilst occasionally accounting for vehicular overloading *** recently,a study has investigated design traffic overloading event frequency using generalised linear regression models(GLRMs),including a power component and negative binomial regressions(NBRs).However,as far as the authors know,artificial neural network models(ANNMs)have never been applied to this *** paper is an attempt to fill in these *** a frequencybased metric of traffic overloading was adopted as a driver of failure ***,two alternative‘frequency'models were specified,calibrated,and *** former was based on a GLRM,the latter on ***,these models were compared using regression plots(RPs),measures of errors(Mo Es)and the ratio between the number of observed vs predicted design load overcoming events to evaluate their *** models analysed more than 2 million weigh-in-motion(WIM)data records from a pilot station on a bridge on a heavily used ring road in Brescia(Italy).Results showed that ANNMs outperformed *** have a higher correlation coefficient(between predicted and target frequencies),lower Mo Es,and a closer-to-unity ratio(between predicted and target frequencies).These findings may increase prediction accuracy of design traffic overloading events and give road authorities more effective traffic management to protect bridges from load hazards.

关键词： Road bridges Traffic load hazard Econometry Machine learning Weigh-in-motion Big-data analysis

Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： Esteban Diaz Edgar Leonardo Salamanca-Medina roberto Tomas Departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction *** high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test *** present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research *** selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive *** the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing ***,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

A high aspect ratio surface micromachined accelerometer based on a SiC-CNT composite material

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Microsystems & Nanoengineering 2024年第2期10卷 219-230页

作者： Jiarui Mo Shreyas Shankar roberto Pezone Guoqi Zhang Sten Vollebregt Laboratory of Electronic Components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands

Silicon carbide(SiC)is recognized as an excellent material for microelectromechanical systems(MEMS),especially those operating in challenging environments,such as high temperature,high radiation,and corrosive ***,SiC bulk micromachining is still a challenge,which hinders the development of complex SiC *** address this problem,we present the use of a carbon nanotube(CNT)array coated with amorphous SiC(a-SiC)as an alternative composite material to enable high aspect ratio(HAR)surface *** using a prepatterned catalyst layer,a HAR CNT array can be grown as a structural template and then densified by uniformly filling the CNT bundle with LPCVD *** electrical properties of the resulting SiC-CNT composite were characterized,and the results indicated that the electrical resistivity was dominated by the *** demonstrate the use of this composite in MEMS applications,a capacitive accelerometer was designed,fabricated,and *** fabrication results showed that the composite is fully compatible with the manufacturing of surface micromachining *** Young’s modulus of the composite was extracted from the measured spring constant,and the results show a great improvement in the mechanical properties of the CNTs after coating with *** accelerometer was electrically characterized,and its functionality was confirmed using a mechanical shaker.

关键词： composite surface electrical

How can the holder trust the verifier? A CP-ABPRE-based solution to control the access to claims in a Self-Sovereign-Identity scenario

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BLOCKCHAIN-RESEARCH AND APPLICATIONS 2024年第3期5卷 22-41页

作者： Buccafurri, Francesco De Angelis, Vincenzo Nardone, roberto Univ Reggio Calabria I-89124 Reggio Di Calabria Italy Univ Calabria I-87036 Arcavacata di Rende CS Italy Univ Naples Parthenope I-80143 Naples Italy

The interest in Self-Sovereign Identity (SSI) in research, industry, and governments is rapidly increasing. SSI is a paradigm where users hold their identity and credentials issued by authorized entities. SSI is revolutionizing the concept of digital identity and enabling the definition of a trust framework wherein a service provider (verifier) validates the claims presented by a user (holder) for accessing services. However, current SSI solutions primarily focus on the presentation and verification of claims, overlooking a dual aspect: ensuring that the verifier is authorized to access the holder's claims. Addressing this gap, this paper introduces an innovative SSI-based solution that integrates decentralized wallets with Ciphertext-Policy Attribute-Based Proxy Re-Encryption (CP-ABPRE). This combination effectively addresses the challenge of verifier authorization. Our solution, implemented on the Ethereum platform, enhances accountability by notarizing key operations through a smart contract. This paper also offers a prototype demonstrating the practicality of the proposed approach. Furthermore, it provides an extensive evaluation of the solution's performance, emphasizing its feasibility and efficiency in real-world applications.

关键词： Blockchain IPFS Self Sovereign Identity Smart contract Access control PROXY RE-ENCRYPTION SCHEME

Wind power potential over northern South America using ERA5-Land global reanalysis

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CLEAN ENERGY 2024年第2期8卷 104-112页

作者： Arregoces, Heli A. Bonivento, Guillermo J. Rojano, roberto Univ Guajira Fac Ingn Grp Invest GISA Riohacha Colombia Univ Antioquia UdeA Fac Ingn SIU Grp Proc Fisicoquim Aplicados Calle 70 52-21 Medellin Colombia

The northernmost region of South America has great potential for wind energy production and is a strategic area for the energy transition. We analysed data from ERA5-Land global reanalysis from 1980 to 2020 to determine the wind power potential in this area. Our aim was to identify areas with a high potential for wind energy that could be used to supply energy in case of drought in the region or increases in fuel prices. We compared data from 19 meteorological stations located in Colombia with ERA5-Land reanalysis data to generate reliable information for the feasibility and operation of wind farms. According to our analysis, the Colombian Caribbean and Coastal Plain have monthly average wind speeds at 90 m ranging from 4.85 to 10.34 m/s and 3.79 to 6.62 m/s, respectively. Based on wind power density calculations, these regions have the highest wind power density in our study, with a monthly average of between 250 and 399 W/m2. The Caribbean Region had a 69% increase in wind power density from January to July compared with the annual average. The wind power density in the plains increased from January to March, while the Mountain Region had higher anomalies from May to October. The Alta Guajira and Paraguana Peninsula have great potential to generate wind energy due to their privileged geographical location. Although ERA5 offers valuable information about wind availability in time and space, it cannot represent the influence of local effects on wind patterns for the Mountain Region. Data from ERA5-Land global reanalysis (1980-2020) are used to determine the wind power potential in the northernmost region of South America to identify areas with a high potential for wind energy, which could be used to supply energy in case of drought or increases in fuel prices. Graphical Abstract

关键词： onshore wind power wind power potential ERA5-Land global reanalysis wind speed ENERGY COLOMBIA REGION ERA5

Syndecans in Alzheimer's disease:pathogenetic mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第9期20卷 2594-2595页

作者： Carmela Rita Balistreri roberto Monastero Cellular Molecular and Clinical Pathological LaboratoryDepartment of BiomedicineNeuroscience and Advanced Diagnostics(Bi.N.D.)University of PalermoPalermoItaly Memory and Parkinson’s disease Center Policlinico“Paolo Giaccone”PalermoDepartment of BiomedicineNeuroscience and Advanced Diagnostics(Bi.N.D.)University of PalermoVia La Loggia 1PalermoItaly

With increasing age,humans become more susceptible to the onset of neurodegenerative diseases(NDs),and among these,Alzheimer's disease(AD)is the most frequent(Nicoletti et al.,2023).NDs are primarily characterized by neuronal loss and atrophy,but also by lesions involving the cerebral and/or cardiovascular system(Balistreri,2021).Lesions such as macroinfa rcts,microinfarcts,hemorrhages,white matter lesions,atherosclerosis,and arteriolosclerosis have also been significantly described in the preclinical stages of cognitive impairment characterizing NDs(Mariani et al.,2007).

关键词： al. Alzheimer cardiovascular

Double-nylon purse-string suture technique: Another addition to the endoscopist's toolbox for full-thickness defect closure

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World Journal of Gastroenterology 2024年第25期30卷 3152-3154页

作者： Angad Walia roberto Paolo Trasolini Neal Shahidi Department of Medicine University of British ColumbiaVancouver V6Z2K5BCCanada

Iatrogenic perforation is the most feared adverse event in *** the expansion of interventional endoscopy in favor of traditional surgery,it is now more crucial than ever to develop effective defect closure *** has culminated in the dissemination of multiple novel closure technologies,including through-the-scope clips,over-the-scope clips,through-the-scope suturing and over-the-scope suturing *** this editorial,we comment on the recent publication by Wang and colleagues discussing the performance of the double-nylon purse-string suture technique in the closure of large(>3 cm)gastric full-thickness *** technique offers a promising,practical and cost-effective approach to closure of large full-thickness defects that can be readily imple-mented across diverse healthcare settings.

关键词： Cancer Endoscopy Endoscopic full-thickness resection Perforation

An efficient improved Gradient Boosting for strain prediction in Near-Surface Mounted fiber-reinforced polymer strengthened reinforced concrete beam

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1148-1168页

作者： Abdelwahhab KHATIR roberto CAPOZUCCA Samir KHATIR Erica MAGAGNINI Brahim BENAISSA Thanh CUONG-LE Structural Section DICEA Polytechnic University of MarcheAncona 60131Italy Centre for Engineering Application&Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh City 70000Vietnam Design Engineering Laboratory Toyota Technological InstituteNagoya 468-8511Japan

The Near-Surface Mounted(NSM)strengthening technique has emerged as a promising alternative to traditional strengthening methods in recent *** the past two decades,researchers have extensively studied its potential,advantages,and applications,as well as related parameters,aiming at optimization of construction ***,there is still a need to explore further,both from a static perspective,which involves accounting for the nonconservation of the contact section resulting from the bond-slip effect between fiber-reinforced polymer(FRP)rods and resin and is typically neglected by existing analytical models,as well as from a dynamic standpoint,which involves studying the trends of vibration frequencies to understand the effects of various forms of damage and the efficiency of *** address this gap in knowledge,this research involves static and dynamic tests on simply supported reinforced concrete(RC)beams using rods of NSM carbon fiber reinforced polymer(CFRP)and glass fiber reinforced polymer(GFRP).The main objective is to examine the effects of various strengthening *** research conducts bending tests with loading cycles until failure,and it helps to define the behavior of beam specimens under various damage degrees,including concrete *** analysis by free vibration testing enables tracking of the effectiveness of the reinforcement at various damage levels at each stage of the loading *** addition,application of Particle Swarm Optimization(PSO)and Genetic Algorithm(GA)is proposed to optimize Gradient Boosting(GB)training performance for concrete strain prediction in NSM-FRP *** GB using Particle Swarm Optimization(GBPSO)and GB using Genetic Algorithm(GBGA)systems were trained using an experimental data set,where the input data was a static applied load and the output data was the consequent *** models of GBPSO and GBGA have been shown to provide highly accurate results for predicting *** model

关键词： NSM technique fiber-reinforced polymer rods static and dynamic analysis GB PSO GA finite element analysis