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Detailing Losses in the M/M/1/1 Transient Loss System

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Acta Mathematicae Applicatae Sinica 2018年第2期34卷 373-385页

作者： pierpaolo FERRANTE National Workers Compensation Authority (INAIL) Department of Occupational and Environmental Medicine Epidemiology and Hygiene (DiMEILA)

This paper is aimed at investigating the transient losses in the M/M/1/1 Erlang loss system. We evaluate the explicit form of the probability distribution of the number of losses in the time interval [0, t） and provide two alternative representations： one based on the iterated derivatives of hyperbolic sinus and cosine and the other on the spherical modified Bessel function of the second kind. The mathematical structures of the transient loss rate and of the transient probability of losing all customers are described and several analytical properties are derived.

关键词： transient losses transient loss rate Erlang bessel functions

Analysis of predictor equations for determining the blast-induced vibration in rock blasting

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International Journal of Mining Science and Technology 2019年第6期29卷 905-915页

作者： Marilena Cardu Dario Coragliotto pierpaolo Oreste DIATI Politecnico di Torino 10129 TorinoItaly IGG-CNR Torino 10129Italy Lochaline Quartz Sand Ltd. Lochaline MinePA805LQ MorvernScotlandUnited Kingdom

The paper proposes a new empirical correlation designed to complement the‘‘site laws"currently used to evaluate the attenuation in the rock masses of vibrations induced by rock *** formula contains a deformed exponential known as the K-exponential,which seems to well represent a large number of both natural and artificial phenomena ranging from astrophysics to quantum mechanics,with some extension in the field of economics and *** validation of the formula was performed via the analysis of vibration data covering a number of case studies,which differed in terms of both operation and rock type.A total of 12 experimental cases were analysed and the proposed formulation exhibited a good performance in 11 of *** particular,the proposed law,which was built using blast test data,produced very good approximations of the points representing the vibration measurements and would thus be useful in organising production ***,the developed formula was found to work less well when a correlation obtained for a given site was applied to another presenting similar types of rocks and operations,and thus should not be employed in the absence of measurements from test data.

关键词： Rock blasting Vibrations Predictor equation Site law K-statistics K-exponential

Systematic lossy error protection based on H.264/AVC redundant slices and flexible macroblock ordering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 900-909页

作者： BACCICHET pierpaolo RANE Shantanu GIROD Bernd Information Systems Lab Department of Electrical Engineering Stanford University Stanford CA 94305 USA

The authors propose a scheme for Systematic Lossy Error Protection (SLEP) of an H.264/AVC compressed video bit stream, using standard compatible features such as redundant slices, and flexible macroblock ordering. The systematic portion consists of a conventional H.264/AVC bit stream. For error resilience, an additional Wyner-Ziv bit stream is also transmitted. The Wyner-Ziv bit stream allows the decoding of a coarsely quantized description of the original video signal, and is efficiently gen- erated by using H.264/AVC redundant slices in conjunction with Reed-Solomon coding. The Wyner-Ziv bit stream is decoded in order to recover the redundant video descriptions, which are used in lieu of portions lost from the original video signal due to channel errors. SLEP allows the video quality to degrade gracefully with worsening channel conditions, and provides a flexible trade-off between the achieved error resilience and the coarseness of the redundant description. The performance can be improved especially for low motion video sequences, by applying SLEP to a region-of-interest in the video frame, using flexible macroblock ordering (FMO). Experimental results provided for two video transmission scenarios, demonstrate the advantages of SLEP over forward error correction (FEC) as an error resilience scheme.

关键词： Wyner-Ziv coding Distributed video coding Side information Systematic source-channel coding Redundant slices Flexible macroblock ordering (FMO)

A Note on Nonlinear Oscillations at Resonance

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Acta Mathematica Sinica,English Series 1987年第4期3卷 351-361页

作者： pierpaolo Omari Fabio Zanolin Dipartimento

Existence of 2π-periodic solutions to the equation +g(x)=p(t) is proved,under sharpnonresonance conditions on the interaction of g(x)/x with two consecutive eigenvalues m2and (m+1)2:touch with the eigenvalues is allo... 详细信息

关键词： lim A Note on Nonlinear Oscillations at Resonance

Climate warming induced a stretch of the breeding season and an increase of second clutches in a passerine breeding at its altitudinal limits

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Current Zoology 2022年第1期68卷 9-17页

作者： Toni MINGOZZI pierpaolo STORINO Giampalmo VENUTO Alessandro MASSOLO Giacomo TAVECCHIA Department of Biology Ecology and Earth Sciences(DiBEST)University of CalabriaVia P.BucciRende 87036Italy Department of Biology Ethology UnitUniversity of PisaVia L.Ghini13Pisa 56126Italy UMR CNRS 6249 Chrono-environnement UniversiteBourgogne Franche-Comte16 Route de GrayBesanc¸on 25030France Animal Demography and Ecology Unit(GEDA-IMEDEA CSIC-UIB)C.M.MarquesEsporles 07190Spain

The increase in the average air temperature due to global warming has produced an early onset of the reproduction in many migratory birds of the Paleartic *** to the“mismatch hypothesis”this response can lead to a decrease in the breeding output when the conditions that trigger the departure from the wintering areas do not match the availability of food resources in the breeding *** used 653 brooding events registered during the period 1991–2013 to investigate the link between climatic variables and individual breeding performance of a partially migratory passerine,the Rock Sparrow Petronia petronia,breeding at the altitude limit of its *** laying date(LD)of the earliest first clutch was associated with local spring(minimum)temperatures but did not show a significant trend during the period *** LD of the latest first clutch had a positive and statistically significant trend,unrelated to local covariates and resulting in a longer breeding season(1.5 days/year).A longer breeding season allowed birds to produce more second clutches,which proportion increased from 0.14 to *** average breeding success was also positively correlated with the average temperature in July and with the duration of the breeding *** to expectations,the most important climate-dependent effect was a stretch of the breeding season due to a significant increase of the LD of the latest first-clutches rather than an earlier breeding *** show how climate changes act on bird populations through multiple paths and stress the need to assess the link between climatic variables and several aspects of the breeding cycle.

关键词： breeding phenology climate warming long-term study Petronia petronia reproductive success

Dispersive liquid-liquid microextraction,an effective tool for the determination of synthetic cannabinoids in oral fluid by liquid chromatography-tandem mass spectrometry

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Journal of Pharmaceutical Analysis 2021年第3期11卷 292-298页

作者： pierpaolo Tomai Alessandra Gentili Roberta Curini Rossella Gottardo Franco Tagliaro Salvatore Fanali Department of Chemistry Sapienza UniversityP.le Aldo Moro 500185RomeItaly Department of Diagnostics and Public Health University of VeronaVeronaItaly and Institute of Translational Medicine and BiotechnologySechenov First Moscow State Medical UniversityMoscowRussia Teaching Committee of Ph.D.School in Natural Science and Engineering University of Verona VeronaItaly

In the present work,dispersive liquid-liquid microextraction(DLLME)was used to extract six synthetic cannabinoids(JWH-018,JWH-019,JWH-073,JWH-200,or WIN 55,225,JWH-250,and AM-694)from oral fluids.A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase(Cogent Bidentate C18;4.6 mm×250 mm,4μm)maintained at 37℃,by eluting in isocratic conditions(water:acetonitrile(25:75,V/V)).Detection was performed using positive electrospray ionization-tandem mass *** parameters affecting DLLME(pH and ionic strength of the aqueous phase,type and volume of the extractant and dispersive solvent,vortex and centrifugation time)were optimized for maximizing *** particular,using 0.5 mL of oral fluid,acetonitrile(1 mL),was identified as the best option,both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME *** select an extraction solvent,a low transition temperature mixture(LTTM;composed of sesamol and chlorine chloride with a molar ratio of 1:3)and dichloromethane were compared;the latter(100μL)was proved to be a better extractant,with recoveries ranging from 73%to 101%by vortexing for 2 *** method was validated according to the guidelines of Food and Drug Administration bioanalytical methods:intra-day and inter-day precisions ranged between 4%and 18%depending on the spike level and analyte;limits of detection spanned from 2 to 18 ng/mL;matrixmatched calibration curves were characterized by determination coefficients greater than ***,the extraction procedure was compared with previous methods and with innovative techniques,presenting superior reliability,rapidity,simplicity,inexpensiveness,and efficiency.

关键词： Microextraction techniques Dispersive liquid-liquid microextraction Illicit drugs Synthetic cannabinoids Silica C-based column

Assessing the effects of alternative fuel treatments to reduce wildfire exposure

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Journal of Forestry Research 2023年第2期34卷 373-386页

作者： Roghayeh Jahdi Liliana Del Giudice Massimo Melis Raff aella Lovreglio Michele Salis Bachisio Arca pierpaolo Duce Institute of BioEconomy(CNR IBE) National Research Council of ItalySassariItaly Faculty of Agriculture and Natural Resources University of Mohaghegh ArdabiliArdabilIran Sardinia Forest Service LanuseiItaly Department of Agriculture University of SassariSassariItaly

Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone *** this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap was applied to assess the potential of alternative fuel treatments for lowering wildfire losses in a 5,740-ha study area in eastern Sardinia,***-seven wildfires at 10-m resolution were simulated considering three wind speeds(15,18,and 21 km h-1)to compare fuel treatments:no treatment(NT),irrigated agroforestry areas with shrub clearing(T1),prescribed fire in eucalyptus stands(T2),and irrigated grasslands(T3).The simulations replicated a recent large wildfire that occurred in the study area(Orrìwildfire,2019)and considered the weather and fuel moisture conditions associated with this *** average wildfire exposure outputs(burned area,probability of burning,conditional flame length,potential crown fire occurrence,and surfaces withflame lengths above 2.5 m)decreased after fuel treatments,compared to no treatment.T1 was the most effective strategy in mitigating wildfire hazards and provided the most significant performance for several wildfire exposure *** only 0.5%of the study area(~30 ha)resulted in a decrease in all wildfire exposure metrics to~10%within the study *** addition,the total surface characterized by high flame length(average>2.5 m)was the lowest in the T1 *** study can help land and fire managers optimize fuel treatment opportunities and wildfire risk mitigation strategies in Mediterranean areas.

关键词： Fuel treatment strategies Fire prevention Mediterranean areas Minimum travel time(MTT) Wildfi re exposure

Takotsubo syndrome presenting with left bundle branch block in an *** hyponatremia a pathogeni c“common ground”?

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Journal of Geriatric Cardiology 2022年第8期19卷 622-625页

作者： Elpidio Santillo pierpaolo D’Onofrio Luciano Marini Demetrio Postacchini Lucio Cardinali Cardiac Rehabilitation Unit Geriatric-Rehabilitative DepartmentIRCCS-INRCAFermoItaly Geriatrics Unit Geriatric-Rehabilitative DepartmentIRCCS-INRCAFermoItaly

Takotsubo syndrome(TTS)is a cardiovas-cular condition characterized by a transi-ent cardiac dysfunction,generally invol-ving the apical segments of left ventriculum,in ab-sence of significant coronary artery disease.[1]It fre-quently affects postmenopausal women,following physical or psychological stress.[2]TTS often mimicks an acute myocardial infarction(AMI),presenting with symptoms as chest pain,dys-pnea,palpitations and,less commonly,pre-syncope and syncope.

关键词： acute cardiac coronary

Dark Matter as Past Matter, a Conjecture

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Journal of High Energy Physics, Gravitation and Cosmology 2021年第2期7卷 452-473页

作者： pierpaolo Perrucci Collepasso (LE) Italy

Up to now several cosmological models have not given yet a satisfactory frame for the existence of Dark Matter (DM) and Dark Energy (DE). This paper attempts to give a geometrical framework for both their emergence and existence. The universe mass/energy densities proportions for Baryonic Matter (BM) and DE exhibit the same relations between the radius and the area of a disc, in which DM matches to the radius squared. That disc may correspond to the base of the Minkowski light cone, which is the front light wave we intercept from the past. I suggest taking time dimension more into consideration, and exploring a new direction on the research of DM and DE as typical relic of BM, positive mass made negative through a continuous phase transition, from a three-dimensional space dimension to the one-dimensional time.

关键词： Dark Matter Gravity