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Probe lifetime around natural satellites with obliquity

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Astrodynamics 2022年第4期6卷 429-439页

作者： Marco Cinelli Hanlun Lei emiliano ortore Christian Circi Istituto di Astrofisica e Planetologia Spaziali(IAPS) Istituto Nazionale di Astrofisica(INAF)Roma 00133Italy School of Astronomy and Space Science and Key Laboratory of Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing 210046China School of Aerospace Engineering Sapienza University of RomeRome 00138Italy Department of Astronautical Electricaland Energy EngineeringSapienza University of RomeRome 00138Italy

The dynamics of a probe orbiting a moon can be significantly influenced by the non-coincidence between the moon's equatorial and orbital ***,we performed a general analysis about the effects of the angle(obliquity)between the above-mentioned planes and of the angle(nodal phasing)between the nodal lines of the mother planet's apparent orbit and the probe orbit on the lifetime of the *** lifetime,strictly correlated to the variations in eccentricity of the probe orbit,was evaluated starting from low values of the semi-major axis,moderate eccentricity,and high inclination to offer high ground spatial resolution and extend latitudinal coverage of the natural *** investigation,carried out through numerical simulations,may be useful for identifying the optimal initial conditions of the probe's orbit elements,leading to an important increase in the probe lifetime in missions devoted to the exploration of natural satellites.

关键词： third-body effect natural satellite probe lifetime

Geometrical approach for an optimal inter-satellite visibility

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Astrodynamics 2021年第3期5卷 237-248页

作者： Marco Cinelli emiliano ortore Giovanni Laneve Christian Circi Department of Mathematics University of Rome Tor VergataRome 00133Italy Department of Astronautical Electrical and Energy EngineeringSapienza University of RomeRome 00138Italy Scuola di Ingegneria Aerospaziale Sapienza University of RomeRome 00138Italy

In the eld of satellite constellations,an important requirement is often represented by the possibility to exchange data among the satellites or exploit mutual visibility to carry out measurements on the parameters of the Earth's ***,recursive and routing algorithms are usually implemented to evaluate inter-satellite visibility ***,to design the con guration of the constellation,it is important to consider the orbital conditions that guarantee the mutual visibility between couples of ***,in this study,a geometric analysis was performed to identify the optimal inter-satellite visibility conditions,expressed in terms of the di erence in the true anomaly between satellites characterized by di erent orbital con *** approach allows a handy constellation design,without performing a numerical *** is particularly useful in the case of a high number of satellites,when numerical techniques require signi cant computational e ***,it is possible to considerably simplify the design of a constellation in which the mutual visibility between couples of satellites is always *** type of constellation,usually referred to as satellite chain,can be exploited in several network services and remote sensing systems devoted to enhancing the knowledge of atmospheric parameters.

关键词： satellite constellation interlink visibility

Lunar orbits for telecommunication and navigation services

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Astrodynamics 2024年第1期8卷 209-220页

作者： Marco Cinelli emiliano ortore Giovanni Mengali Alessandro A.Quarta Christian Circi Istituto di Astrofisica e Planetologia Spaziali(IAPS) Istituto Nazionale di Astrofisica(INAF)Via del Fosso del Cavaliere 100Roma00133Italy School of Aerospace Engineering Sapienza University of RomeVia Salaria 881Rome00138Italy Department of Civil and Industrial Engineering University of PisaPisa56122Italy Department of Astronautical Electricaland Energy EngineeringSapienza University of RomeVia Salaria 851Rome00138Italy

Orbits that are frozen in an averaged model,including the effect of a disturbing body laying on the equatorial plane of the primary body and the influence of the oblateness of the primary body,have been applied to probes orbiting the *** this scenario,the main disturbing body is represented by the Earth,which is characterized by a certain obliquity with respect to the equatorial plane of the *** a consequence of this,and of the perturbing effects that are not included in the averaged model,such solutions are not perfectly ***,the orbit eccentricity,inclination,and argument of pericenter present limited variations and can be set to guarantee the fulfillment of requirements useful for lunar telecommunication missions and navigation *** advantage of this,a practical case of a Moon-based mission was investigated to propose useful solutions for potential near-future applications.

关键词： lunar orbits frozen orbits lunar telecommunications lunarnavigation services

Recycling of reclaimed fibers from end-of-life tires in hot mix asphalt

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第5期7卷 678-687页

作者： Edoardo Bocci emiliano Prosperi Faculty of Engineering eCampus UniversityNovedrateCO 22060Italy Dipartimento di Ingegneria Civile Edile e Architettura UniversitàPolitecnica delle MarcheAncona 60131Italy

Nowadays, the disposal of end-of-life tires(ELT) is worldwide one of the major concerns for the environment as well as for public health. Crumb rubber and steel wires, the main byproducts(in terms of weight) deriving from the ELT processing, can be recycled in several ways. However, the textile fiber, representing about 10% of the waste by weight, is typically not reused and ends up in landfills or incinerators. The present paper deals with the use of reclaimed fibers from ELT in hot mix asphalt(HMA), with the aim to improve its performance. The study included the preliminary characterization of the fiber through microscope observation and Fourier trans form infrared(FTIR) spectroscopy and then the investigation of the mechanical properties of HMA containing ELT fibers, in comparison with an ordinary HMA with no fibers. In particular, indirect tensile strength(ITS), indirect tensile stiffness modulus(ITSM), semi-circular bending(SCB), three point bending(3PB)and indirect tensile fatigue(ITF) tests were carried out. The results showed that the use of ELT fibers does not reflect in a significant improvement in terms of strength and stiffness properties. However, the ELT fibers determine a noticeable increase of the HMA resistance to fatigue, probably related to the ability of the fibers in sewing the micro-crack edges and contrasting the macro-crack opening.

关键词： Road engineering Hot mix asphalt End-of-life tire Fiber Fatigue Recycling

Cross-Layer Framework for Fine-Grained Channel Access in Next Generation High-Density Wi Fi Networks

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China Communications 2016年第2期13卷 55-67页

作者： ZHAO Haitao ZHANG Shaojie emiliano Garcia-Palacios College of Electronic Science and Engineering National University of Defense Technology ECIT Institute Queen's University Belfast

Densely deployed Wi Fi networks will play a crucial role in providing the capacity for next generation mobile internet. However, due to increasing interference, overlapped channels in Wi Fi networks and throughput efficiency degradation, densely deployed Wi Fi networks is not a guarantee to obtain higher throughput. An emergent challenge is how to effi ciently utilize scarce spectrum resources, by matching physical layer resources to traffi c demand. In this aspect, access control allocation strategies play a pivotal role but remain too coarse-grained. As a solution, this research proposes a flexible framework for fine-grained channel width adaptation and multi-channel access in Wi Fi networks. This approach, named SFCA(Subcarrier Fine-grained Channel Access), adopts DOFDM(Discontinuous Orthogonal Frequency Division Multiplexing) at the PHY layer. It allocates the frequency resource with a subcarrier granularity, which facilitates the channel width adaptation for multi-channel access and thus brings more fl exibility and higher frequency efficiency. The MAC layer uses a frequencytime domain backoff scheme, which combines the popular time-domain BEB scheme with a frequency-domain backoff to decrease access collision, resulting in higher access probability for the contending nodes. SFCA is compared with FICA(an established access scheme)showing significant outperformance. Finally we present results for next generation 802.11 ac Wi Fi networks.

关键词： channel width adaptation channel access high-density WiFi

Towards very high RAP content asphalt mixes:A comprehensive performance-based study of rejuvenated binders

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第6期8卷 1022-1035页

作者： Marco Pasetto Andrea Baliello Giovanni Giacomello emiliano Pasquini Department of Civil Environmental and Architectural Engineering(ICEA)University of PaduaPaduaItaly

Hot recycling of reclaimed asphalt pavement(RAP)from replacement of deteriorated asphalt pavements is a widespread technique,and able to ensure clear economic and environmental *** this reason,paving industries,agencies and researchers are spending significant efforts in order to maximize such advantages by increasing the amount of RAP within new asphalt ***,adequate performance of recycled mixtures must be guaranteed despite the re-use of high amounts of RAP which involves the presence of aged,oxidized and stiffened *** this perspective,the present study aimed at evaluating the rheological properties at mid-service and high-service temperatures of bituminous blends composed by 40%of virgin binder and 60%of aged rejuvenated bitumen(simulating the aged hard bitumen coming from the RAP).Such proportion was selected to represent a high recycling rate of RAP(about 60%of the total weight of aggregates,RAP included).A chemical commercial additive at the liquid state was selected as rejuvenator;it was dosed at the optimum content based on empirical and rheological preliminary *** performance of the recycled blend was then compared to that of a virgin reference *** shear rheometer tests were carried out to determine the master curves and the failure characteristics(at mid and high service temperatures)of the selected *** effect of aging(related to the durability over the material lifetime)was also studied analyzing binders’responses in unaged,shortterm and long-term aged ***,experimental findings demonstrated the efficacy of the rejuvenation of recycled binders containing very high amount of aged bitumen.

关键词： Pavement engineering Hot recycling Reclaimed asphalt Rejuvenation DSR Rheology

Reconfigurable elastomeric graded-index optical elements controlled by light

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Light(Science & Applications) 2018年第1期7卷 964-972页

作者： Angelo Angelini Federica Pirani Francesca Frascella emiliano Descrovi Department of Applied Science and Technology(DISAT) Politecnico di TorinoC.so Duca degli Abruzzi 24Torino IT-10129Italy Center for Sustainable Future Technologies@PoliTo Istituto Italiano di TecnologiaC.so Trento 21Torino IT-10129Italy

In many optical applications,there is an increasing need for dynamically tunable optical elements that are able to shape the wavefront of light‘on demand’.In this work,an elastomeric easy-to-fabricate optical element whose transmission functions can be reversibly phase configured by visible light is *** light responsivity of proper azopolymers incorporated within an elastomeric matrix is exploited to induce a light-controlled graded refractive index(GRIN)distribution within the bulk *** induced refractive index distribution is continuous and conformal to the intensity profile of the illumination at moderate power.A 100mW doubled-frequency Nd:YAG Gaussian beam focused to a 650μm waist is shown to induce a maximum relative refractive index change of~0.4%in the elastomeric matrix,with an approximately parabolic *** restoring characteristics of the elastomeric matrix enable full recovery of the initial homogeneous refractive index distribution within a few seconds when the incident laser is switched *** an exemplary application,the configurable GRIN element is used in a microscope-based imaging system for light control of the effective focal length.

关键词： optical switched index

Long-noncoding RNAs as epigenetic regulators in neurodegenerative diseases

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Neural Regeneration Research 2023年第6期18卷 1243-1248页

作者： Paola Ruffo Francesca De Amicis emiliano Giardina Francesca Luisa Conforti Medical Genetics Laboratory Department of PharmacyHealth and Nutritional SciencesUniversity of CalabriaRendeItaly Department of Pharmacy Health and Nutritional SciencesUniversity of CalabriaRendeItaly Genomic Medicine Laboratory UILDM IRCCS Fondazione Santa LuciaRomeItaly Department of Biomedicine&Prevention Tor Vergata University of RomeRomeItaly

The growing and rapid development of high-throughput sequencing technologies have allowed a greater understanding of the mechanisms underlying gene expression *** the epigenome and epitranscriptome directs the fate of the transcript influencing the functional outcome of each *** this context,non-coding RNAs play a decisive role in addressing the expression regulation at the gene and chromosomal ***-noncoding RNAs,consisting of more than 200 nucleotides,have been shown to act as epigenetic regulators in several key molecular processes involving neurodegenerative disorders,such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis and Huntington’s ***-noncoding RNAs are abundantly expressed in the central nervous system,suggesting that their deregulation could trigger neuronal degeneration through RNA *** evaluation of their diagnostic significance and therapeutic potential could lead to new treatments for these diseases for which there is no cure.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis epigenetic mechanism Huntington’s disease long-noncoding RNAs neurodegenerative disease non-coding RNAs Parkinson’s disease

The Boson peak interpretation and evolution in confined amorphous water

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 16-23页

作者： Francesco Mallamace Carmelo Corsaro Domenico Mallamace Sow-Hsin Chen emiliano Fratini Piero Baglioni Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridge MA 02139USA Center for Polymer Studies and Department of Physics Boston UniversityBoston MA 02215USA Dipartimento MIFT Universita di MessinaMessina 1-98166Italy Consorzio Interutiiversitario per lo Sviluppo dei Sistemi a Grande Interfase-CSGI Universita di FirenzeSesto FiorentinoFirenze 1-50019Italy Dipartimento di Chimica"Ugo Schiff" Universita di FirenzeSesto FiorentinoFirenze 1-50019Italy

We study the evolution of the Boson peak for water confined in cement paste obtained by means of Inelastic Neutron Scattering from room temperature to the deep supercooled *** analyze the data in terms of a universal-like model,developed for glass forming liquids in the frame of the energy *** such a way it is possible to discriminate between the fragile and strong glass forming character of supercooled liquids and the dynamical crossover,fragile to strong,between ***,we confirm the link between the Boson peak and the water *** particular,the main result is represented by a crossover from a local energetic minima configuration to that characteristic of saddle points on going towards the deep supercooled regime up to the dynamical arrest.

关键词： water water confined in cement Boson peak inelastic neutron scattering