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Microscopic analysis of spherical to γ-soft shape transitions in Zn isotopes

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science China(Physics,Mechanics & Astronomy) 2011年第2期54卷 222-226页

作者： VRETENAR dario Physics Department Faculty of ScienceUniversity of Zagreb

The rapid transition between spherical and γ-soft shapes in Zn isotopes in the mass A 70 region,is analyzed using excitation spectra and collective wave functions obtained by diagonalization of a five-dimensional Hamiltonian for quadrupole vibrational and rotational degrees of freedom,with parameters determined by constrained self-consistent relativistic mean-field calculations for triaxial *** microscopic potential energy surfaces,together with the characteristic collective observables,illustrate a rapid transition from near spherical shape at the N = 40 subshell,to γ-soft deformed shapes for lighter *** calculated spectra display fingerprints of a second-order shape phase transition that can be approximately described by the E(5) analytic solution.

关键词： quantum phase transitions E(5) critical-point symmetry five-dimensional Hamiltonian

On the genetic distinctiveness of tailorbirds(Cisticolidae:Orthotomus)from the south-east Asian mainland with the description of a new subspecies

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Avian Research 2018年第3期9卷 214-225页

作者： Jerome Fuchs dario Zuccon Institut de systématique EvolutionBiodiversitéUMR7205 CNRS MNHN UPMC EPHESorbonne UniversitéMuséum National d’Histoire NaturelleCP 5157 rue Cuvier75231 Paris Cedex 05France

Background: The Cambodian Tailorbird(Orthotomus chaktomuk) was one of the most recent major ornithological discoveries in south-east Asia as it originated from lowland seasonally flooded scrub within the densely inhabited floodplain around the Tonle sap, Mekong and Bassac rivers(Cambodia). The Cambodian Tailorbird is sister to the Dark-necked Tailorbird(O. atrogularis) with very limited genetics and biometric differentiation. Between 2004 and 2012, evidences of a new population of Ashy Tailorbird(O. ruficeps) in sE Cambodia/Vietnam accumulated but no museum specimens were ever reported. The Ashy Tailorbird currently consists of eight subspecies among which the closest geographical populations, O. r. cineraceus(sE Burma to Malay Peninsula, sumatra, Bangka and Belitung) and O. r. borneoensis(Borneo), are allopatric. subspecific identification of the Cambodian Ashy Tailorbirds individuals was not possible because of the limited differences in plumage among ***: We inspected the Orthotomus ruficeps specimens housed at the Museum National d'Histoire Naturelle(Paris) and discovered five specimens of O. ruficeps collected by Louis Rodolphe Germain in ‘Cochinchina'(corresponding to southern Vietnam) during the nineteenth century. We sequenced one mitochondrial locus and gathered biometric data from these specimens and compared them with other Orthotomus ***: The Ashy Tailord population from sE Cambodia and Vietnam is distinct from the two geographically close subspecies O. r. borneoensis(1.7%) and O. r. cineraceus(1.3%). O. chaktomuk is nested within O. atrogularis in the mitochondrial gene tree. The sE Cambodia/Vietnam population of O. ruficeps is distinct from the two other subspecies in bill ***: Our study described the biometric and molecular distinctiveness of a recently re-discovered population of Ashy Tailord in sE Cambodia and Vietnam and suggests that this population constitutes an independent evolutionary lineage that we de

关键词： Orthotomus Differentiation subspecies Taxonomy

Parabolic Trough Collector and Central Receiver Coupled with Fresnel Lens:Experimental Tests

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International Journal of Automation and computing 2020年第4期17卷 572-587页

作者： Angelica Palacios dario Amaya Olga Ramos Universidad Militar Nueva Granada Bogota 110121Colombia

Renewable energies have a high impact on power energy production and reduction of environmental pollution worldwide,so high efforts have been made to improve renewable technologies and research about *** paper presents the thermal performance results obtained by simulation and experimental tests of a parabolic trough collector with central receiver coupled to Fresnel lens,under different configurations on the *** simulation method was computational fluid dynamics(CFD)analysis in solidWorks(R)soft-ware tool,which works with Naiver-stokes equations to converge on a *** tests were formed with all configurations proposed and three observations for each one,a total of 12 observations were performed in all *** a result,the best thermal performance in simulation was achieved with the Fresnel lens and black pipe collector,with a maximum temperature of 116℃under 1000 W/m^2 radiation,the same system achieved in experimental tests a maximum temperature of 96℃with a radiation of 983 W/m^2.

关键词： solar collector parabolic trough collector Fresnel lens thermal conductivity solar power

Learning the optimal state-feedback via supervised imitation learning

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Astrodynamics 2019年第4期3卷 361-374页

作者： Dharmesh Tailor dario Izzo Advanced Concepts Team European Space AgencyNoondwijk2201 AZthe Netherlands

Imitation learning is a control design paradigm that seeks to learn a control policy reproducing demonstrations from expert *** substituting expert demonstrations for optimal behaviours,the same paradigm leads to the design of control policies closely approximating the optimal *** approach requires training a machine learning algorithm(in our case deep neural networks)directly on state-control pairs originating from optimal *** have shown in previous work that,when restricted to low-dimensional state and control spaces,this approach is very successful in several deterministic,non-linear problems in *** this work,we refine our previous studies using as a test case a simple quadcopter model with quadratic and time-optimal objective *** describe in detail the best learning pipeline we have developed,that is able to approximate via deep neural networks the state-feedback map to a very high *** introduce the use of the softplus activation function in the hidden units of neural networks showing that it results in a smoother control profile whilst retaining the benefits of *** show how to evaluate the optimality of the trained state-feedback,and find that already with two layers the objective function reached and its optimal value differ by less than one *** later consider also an additional metric linked to the system asymptotic behaviour-time taken to converge to the policy’s fixed *** respect to these metrics,we show that improvements in the mean absolute error do not necessarily correspond to better policies.

关键词： optimal control deep learning imitation learning G&CNET

Ensemble learning framework for landslide susceptibility mapping:Different basic classifier and ensemble strategy

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Geoscience Frontiers 2023年第6期14卷 170-190页

作者： Taorui Zeng Liyang Wu dario Peduto Thomas Glade Yuichi s.Hayakawa Kunlong Yin Institute of Geological survey China University of GeosciencesWuhan 430074China ENGAGE—Geomorphic systems and Risk Research Department of Geography and Regional ResearchUniversity of Vienna1010 ViennaAustria Faculty of Engineering China University of GeosciencesWuhanChina Department of Civil Engineering University of Salerno84084 SalernoFiscianoItaly Faculty of Environmental Earth science Hokkaido UniversityHokkaido 060-0810Japan

The application of ensemble learning models has been continuously improved in recent landslide susceptibility research,but most studies have no unified ensemble ***,few papers have discussed the applicability of the ensemble learning model in landslide susceptibility mapping at the township *** study aims at defining a robust ensemble framework that can become the benchmark method for future research dealing with the comparison of different ensemble *** this purpose,the present work focuses on three different basic classifiers:decision tree(DT),support vector machine(sVM),and multi-layer perceptron neural network model(MLPNN)and two homogeneous ensemble models such as random forest(RF)and extreme gradient boosting(XGBoost).The hierarchical construction of deep ensemble relied on two leading ensemble technologies(i.e.,homogeneous/heterogeneous model ensemble and bagging,boosting,stacking ensemble strategy)to provide a more accurate and effective spatial probability of landslide *** selected study area is Dazhou town,located in the Jurassic red-strata area in the Three Gorges Reservoir Area of China,which is a strategic economic area currently characterized by widespread landslide *** on a long-term field investigation,the inventory counting thirty-three slow-moving landslide polygons was *** results show that the ensemble models do not necessarily perform better;for instance,the Bagging based DT-sVM-MLPNNXGBoost model performed worse than the single XGBoost *** the eleven tested models,the stacking based RF-XGBoost model,which is a homogeneous model based on bagging,boosting,and stacking ensemble,showed the highest capability of predicting the landslide-affected ***,the factor behaviors of DT,sVM,MLPNN,RF and XGBoost models reflected the characteristics of slow-moving landslides in the Three Gorges reservoir area,wherein unfavorable lithological conditions and intense human engineering activitie

关键词： Three Gorges Reservoir Area Landslide susceptibility mapping Ensemble learning framework Uncertainty research

Chemical substances present in discharge water generated by laundry industry:Analytical monitoring

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Water science and Engineering 2023年第4期16卷 324-332页

作者： dario Lacalamita Chiara Mongioví Grégorio Crini Chrono-environnement Laboratory University of Franche-Comté16 Route de GrayBesançon 25000France

To our knowledge,precise data concerning the pollution in terms of qualitative and quantitative fluctuations in discharge water from the laundry sector have seldom been *** study investigated the chemical composition of the discharge water from a laundry *** 160 chemical substances and 15 standard water parameters were *** results showed that the discharge water presented both inorganic and organic polycontamination with a high degree of qualitative and quantitative ***,of all monitored substances,only five metals(Al,Cu,Fe,sr,and Zn),five minerals(P,Ca,K,Na,and s),and alkylphenols were systematically present and *** a daily average water flow of 129 m^(3),the released metal flux was 356 g/***,such as trichloromethane,brominated diphenyl ether(BDE)47,and fluorides,were occasionally found and *** substances,such as chlorophenols,organo-tins,and pesticides were never *** the samples had quantifiable levels in the chemical oxygen demand(COD),biological oxygen demand(BOD),and *** the concentrations of Zn(8.3 g/d),Cu(21.4 g/d),and BOD(57.4 g/d)were close to or above the regulatory values:74.0 g/d for Zn,9.0 g/d for Cu,and 57.0 kg/d for *** data obtained from this study are useful to the choice of additional treatments for the reduction of pollutant fluxes.

关键词： Laundry Discharge water Chemical analysis Water parameter Chemical substance

Target selection for a small low-thrust mission to near-Earth asteroids

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Astrodynamics 2018年第3期2卷 249-263页

作者： Alessio Mereta dario Izzo Advanced Concepts Team European Space Research and Technology CenterNoordwijk 12201 AZNetherlands

The preliminary mission design of spacecraft missions to asteroids often involves,in the early phases,the selection of candidate target *** final result of such an analysis is a list of asteroids,ranked with respect to the necessary propellant to be used,that the spacecraft could potentially *** this paper we investigate the sensitivity of the produced asteroids rank to the employed trajectory model in the specific case of a small low-thrust propelled spacecraft beginning its journey from the sun–Earth L2 Lagrangian point and heading to a rendezvous with some near-Earth *** consider five increasingly complex trajectory models:impulsive,Lambert,nuclear electric propulsion,nuclear electric propulsion including the Earth’s gravity,solar electric propulsion including the Earth’s gravity and we study the final correlation between the obtained target *** find that the use of a lowthrust trajectory model is of great importance for target selection,since the use of chemical propulsion surrogates leads to favouring less attractive options 19%of times,a percentage that drops to 8%already using a simple nuclear electric propulsion model that neglects the Earth’s gravity effects and thrust dependence on the solar *** also find that for the study case considered,a small interplanetary Cubesat named M-ARGO,the inclusion of the Earth’s gravity in the considered dynamics does not affect the target selection significantly.

关键词： low-thrust asteroid selection near-Earth asteroids mission analysis

Melt Crystallization of Poly(butylene 2,6-naphthalate)

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Chinese Journal of Polymer science 2020年第4期38卷 311-322,I0004页

作者： Qian Ding Michelina soccio Nadia Lotti dario Cavallo Rene Androsch school of Packaging Design and Art Hunan University ofTechnologyZhuzhou 412007China Department ofCivil ChemicalEnvironmental and Materials EngineeringUniversity of BolognaVia Terracini 28Bologna 40131Italy Department of Chemistry and Industrial Chemistry University of GenovaViaDodecaneso31Genova 16146Italy Interdisciplinary Center for Transfer-oriented Research in Natural sciences(IWE TFN) Martin Luther University Halle-WittenbergHalle/Saale 06099Germany

Poly(butylene 2,6-naphthalate)(PBN)is a crystallizable linear polyester containing a rigid naphthalene unit and flexible methylene spacer in the chemical repeat *** materials made of PBN exhibit excellent anti-abrasion and low friction properties,superior chemical resista nee,and outstanding gas barrier *** of the properties rely on the presence of crystals and the formatio n of a semicrystalline *** develop specific crystal structures and morphologies during cooling the melt,precise information about the melt-crystallization process is *** review article summarizes the current knowledge about the temperature-controlled crystal polymorphism of *** rather low supercooling of the melt,with decreasi ng crystal I izatio n temperature,0'-and a-crystals grow directly from the melt and organize in largely different spherulitic *** of a-crystals at high supercooling may also proceed via intermediate formation of a transient monotropic liquid crystalline structure,then yielding a non-spherulitic semicrystalline *** of PBN is rather fast since its suppression requires cooling the melt at a rate higher than 6000 K-s_*** this reason,investigation of the two-step crystallization process at low temperatu res requires application of sophisticated experimental *** in elude temperatureresolved X-ray scattering techniques using fast detectors and synchrotron-based X-rays and fast scanning chip *** scanning chip calorimetry allows freezi ng the transie nt liquid-crystalline structure before its con version into a-crystals,by fast cooling to below its glass transition *** an alysis using polarized-light optical microscopy reveals its texture and X-ray scatteri ng con firms the smectic arrangement of the *** combination of a large variety of experimental techniques allows obtaining a complete picture about crystallization of PBN in the entire

关键词： Poly(butylene 2,6-naphthalate) Crystallization Polymorphism semicrystalline morphology

Large Eddy simulation of the By-pass Transition Process under Different Inlet Turbulence Conditions

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Journal of Thermal science 2021年第6期30卷 2112-2121页

作者： BARsI dario COsTA Carlo LENGANI Davide sIMoni Daniele UBALDI Marina DIME-University of Genova Via Montallegro 11-16145 GenovaItaly

The transition process of the boundary layer developing over a flat plate with elevated inlet Free stream Turbulence Intensity(FsTI)has been studied by means of Large Eddy simulation(LEs).To this purpose,four cases with different inflow disturbances have been tested varying the magnitude and the length scale of *** has been performed by using the finite-volume ANsYs Fluent *** computational domain,which was constituted by a rectangular domain with a zero thickness plate,was based on an ERCOFTAC test case in order to provide a validation with a well-known set of data by comparing the boundary layer integral parameters and mean and fluctuating streamwise velocity *** four cases were discussed within the paper by looking at classical statistical properties as well as advanced post-processing *** was shown that the decrease in the free stream turbulence level postpones the transition location,whereas the variation of the integral length scale has a very low influence on the distribution of the time-mean flow *** Orthogonal Decomposition(POD)has been applied to the instantaneous LEs flow fields in order to provide a statistical representation of the structures responsible for transition and their response to free-stream turbulence intensity and length *** presence of vortical filaments parallel to the wall,typically referred as boundary layer streaks,is clearly identified;their characteristic dimensions and how they change as a function of FsTI properties were analyzed within the paper.

关键词： by-pass transition Large Eddy simulation(LEs) Proper Orthogonal Decomposition(POD) boundary layer streaks