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Analytical model of IoT CoAP traffic

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Digital Communications and Networks 2019年第2期5卷 63-68页

作者： rolando Herrero College of Engineering Northeastern University02115BostonMAUSA

The Constrained Application Protocol (CoAP) is a mechanism that enables the efficient transmission of information in the context of Wireless Sensor Networks (WSNs) characteristic of the Internet of Things (IoT). CoAP is specifically intended to work well with low complexity sensors that have lim让ed access to computational resources. And because it lacks the overhead of other more sophisticated transport protocols,让 is suitable for high packet loss wireless networks. Relying on the User Datagram Protocol (UDP), CoAP introduces, among other things, confirmable and non-confirmable message types, depending on the nature of the source data. This paper presents a novel analytical model that can relate the application to network packet loss and be used to estimate the effect of lossy wireless channels in CoAP scenarios. Moreover, the model is ultimately validated by an experimental framework in which theoretical and experimental results are compared.

关键词： CoAP UDP WSN IoT Wireless

Hydrocarbon distribution along the Soapaga thrust(Eastern Cordillera, Colombia) based on new strategic geochemistry samples

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Acta Geochimica 2022年第3期41卷 335-350页

作者： Eduardo A.Rossello rolando Di Primio Departamento de Ciencias Geologicas Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaCONICET-IGEBAPabellon II1428 Buenos AiresArgentina Lundin Energy Norway LysakerNorway

The Colombian Eastern Cordillera constitutes a region with potential for finding hydrocarbon reserves that are still under-explored, despite the existence of oil and tar sand production. The intense tectonic deformation affects the petroleum systems and increases exploration challenges due to the different generation, maturation, and entrapment conditions that they produce. Diverse geochemical analysis conducted on strategic samples determines that these are likely generated by the same anoxic marine source rock type. Two source rock samples we investigated are characterized by very different biomarker signals as compared to the tar sands and oil samples. Both samples are dominated by hopanes as compared to tri-and tetracyclic terpanes, with very low(Tibasosa Formation) to no(Chipaque Formation) extended tricyclic terpanes. The Soapaga Thrust, along which the analyzed samples are located, has exercised first-rate regional structural control of the distribution of hydrocarbons in the studied area. The uplift of their Mesozoic hanging wall produces intense erosion with sediment transport towards the eastern footwall forming the present infill of the Arcabuco basin. The kitchen areas were connected with the shallower entrapment sectors where excellent reservoir levels such as the Picacho Formation before the Soapaga Thrust movement. The high degree of biodegradation observed in the Picacho Fm. tar sands support early charge before the Soapaga thrust movement, and severe biodegradation following the thrust movement when hydrocarbon supply from the kitchen was interrupted. This work aims to contribute to a better understanding of the geochemical characteristics of the petroleum systems due to the action of the Soapaga Thrust.

关键词： Hydrocarbon geochemistry Soapaga thrust Eastern Cordillera Colombia

Arthropods associated with medicinal plants in coastal South Carolina

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Insect Science 2007年第6期14卷 519-524页

作者： rolando LOPEZ B. MERLE SHEPARD Clemson University Department of Entomology Soils and Plant Sciences and Coastal Research and Education CenterCharleston South Carolina USA

Arthropods were sampled from feverfew [Tanacetum parthenium （L.） Schultz- Bip], Echinacea purpurea （L.） Moench, Echinacea pallida （Nutt.） Nutt., Valeriana officinalis L., and St. John＇s wort （Hypericum perforatum L.） during 1998-2001. In addition, arthropods were sampled on tansy （Tanacetum vulgare L.） from 2001-2004. In general, 50-60 arthropod species where collected and identified among all of the medicinal plant species. Among the predators, Orius insidiosus （Say）（Hemiptera： Anthocoridae）, Geocoris punctipes （Say）（Hemiptera： Lygaeidae） and spiders were most abundant from 1998-2004. The three-cornered alfalfa hopper, Spissistilus festinus （Say）, was the most abundant herbivore found from 1998 to 2001. Orius insidiosus and G. punctipes were 3-4 times more abundant on T. parthenium than on any other medicinal plant species. Based on the numbers of predatory arthropods found on T. parthenium, this crop could be suitable as a companion or ＂banker＂ plant to attract and maintain populations of predators, especially O. insidiosus and G. punctipes. Whitefly nymphs attacked by predators with piercing/sucking mouthparts are easily identified using a microscope because of the general appearance of the carcass left by the predators. Thus, populations of predators on T. parthenium suppressed Bemisia tabaci populations on E. purpurea when these crops were planted as companion crops.

关键词： companion plants Geocoris punctipes medicinal plants Orius insidiosus,predators

Trees of Panama: A complete checklist with every geographic range

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Forest Ecosystems 2020年第3期7卷 526-538页

作者： Richard Condit Salomón Aguilar rolando Pérez Morton Arboretum 4100 Illinois Rte.53Lisle60532ILUSA Smithsonian Tropical Research Institute Panama CityPanama

Background Central America is one of the most diverse floristic provinces in the world,but comprehensive plant lists for the region are incomplete and need frequent *** geographic ranges of individual species are seldom *** detailed forest inventory plots of Panama thus lack a global geographic *** order to provide one,we assembled a thoroughly vetted checklist of all tree species of Panama,along with an estimate of each one’s range size based on published specimen *** 1)Panama has 3043 tree species in 141 families and 752 genera;57.6%were≥10 m tall and 16.9%were 3-5 m tall.2)The widest ranges were>1.5×107 km2,covering the entire neotropics and reaching>30∘latitude;12.4%of the species had ranges exceeding 107 *** median range was 6.9×105 km2.3)At the other extreme,16.2%of the species had a range<20,000 km2,a criterion suggesting endangered status.4)Range size increased with a tree species’height and varied significantly among families.5)Tree census plots,where we mapped and measured all individuals,captured 27.5%of the tree species,but a biased selection relative to range size;only 4.5%of the species in plots had ranges<20,000 *** Our checklist of the trees of Panama,based on rigorous criteria aimed at matching plot censuses,is 20%larger than *** recording species’maximum heights,we allow comparisons with other regions based on matching definitions,and the range sizes provide a quantitative basis for assessing extinction *** next goal is to merge population density from plot censuses to add rigor to predictions of extinction risk of poorly-studied tropical tree species.

关键词： red Trees of Panama A complete checklist with every geographic range

On the calibration of rotational augmentation models for wind turbine load estimation by means of CFD simulations

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Acta Mechanica Sinica 2020年第2期36卷 306-319页

作者： Belen Soledad burgos Tafur Elia Daniele Bernhard Stoevesandt Philipp Thomas Fraunhofer IWES Am Seedeich 4527572 BremerhavenGermany Flensburg University of Applied Sciences Wind Energy Technology InstituteNordstraße224943 FlensburgGermany

In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and *** on an analysis of the NREL Phase VI wind turbine,the novel modeling is presented,which uses as base line the formulation proposed by Chaviaropoulos and *** model is calibrated based on CFD simulations using *** corresponding correction of the two dimensional polars is straightforward implemented within MoWiT,an in-house software for load *** novel formulation results in improved lift and drag coefficients prediction in all considered cases,reducing the deviation with respect to the rotating CFD cases down to few *** optimal configuration including the correction for tip effects of Shen shows better agreements at the very tip of the *** the range of applicability for large wind turbine rotor blades based on a virtual 10MW rotor model is discussed.

关键词： calculation. rotational correction

Dynamic Simulation of Cracked Buildings for Damage Detection

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Structural Durability & Health Monitoring 2020年第3期14卷 187-204页

作者： Alan Alonso-Rivers rolando Salgado-Estrada Faculty of Engineering Department of CivilAmbiental EngineeringSchool of Mining and Petroleum EngineeringUniversity of Alberta6361 Donadeo Innovation Center for Engineering(ICE)EdmontonAlbertaT6H 1H9Canada Faculty of Engineering of the Construction and the Habitat Campus VeracnuzUniversidad VeracruzanaBoca del RioVeracruzCP 94294México

A dynamic simulation method for cracked structures is implemented to determine their dynamic response with the purpose of evaluating their structural *** procedure makes possible the si mulation of three-dimensional cracked *** excitation force is randomly generated to simulate wind *** is assumed the structure remains in the elastic range,which allows for each mode that contributes to its dynamic response to be *** results indicate that the presence of damage causes changes in the modals parameters of the structure as accurate as other similar methods proposed for simpler ***,it is concluded that the proposed method is a reliable way to evaluate the dynamic behavior of three-dimensi onal cracked building structures.

关键词： Dynamic simulation cracked structures damage detection structural dynamic

Spatial-Resolution Independent Object Detection Framework for Aerial Imagery

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Computers, Materials & Continua 2021年第8期68卷 1937-1948页

作者： Sidharth Samanta Mrutyunjaya Panda Somula Ramasubbareddy SSankar Daniel burgos Deptartment of CSA Utkal UniversityBhubaneswar751004India Department of Information Technology VNRVJIETHyderabad500090India Department of CSE Sona College of TechnologySalem636005India Research Institute for Innovation&Technology in Education(UNIR iTED) Universidad Internacional de La Rioja(UNIR)Logroño26006Spain

Earth surveillance through aerial images allows more accurate identification and characterization of objects present on the surface from space and airborne *** progression of deep learning and computer vision methods and the availability of heterogeneous multispectral remote sensing data make the field more fertile for *** the evolution of optical sensors,aerial images are becoming more precise and larger,which leads to a new kind of problem for object detection *** paper proposes the“Sliding Region-based Convolutional Neural Network(SRCNN),”which is an extension of the Faster Region-based Convolutional Neural Network(RCNN)object detection framework to make it independent of the image’s spatial resolution and *** sliding box strategy is used in the proposed model to segment the image while *** proposed framework outperforms the state-of-the-art Faster RCNN model while processing images with significantly different spatial resolution *** SRCNN is also capable of detecting objects in images of any size.

关键词： Computer vision deep learning multispectral images remote sensing object detection convolutional neural network faster RCNN sliding box strategy

TREXIT:initial experience with transperineal prostate biopsy under local anesthesia in an outpatient setting in South East Asia

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Asian Journal of Andrology 2021年第5期23卷 543-544页

作者： Arianto Yuwono rolando Salada Teck Wei Tan Department of Urology Tan Tock Seng Hospital11 Jalan Tan Tock SengSingapore 308433Singapore

Dear Editor,Compared to transrectal prostate biopsy,transperineal(TP)prostate biopsy avoids rectal bacteria,and thus,significantly reduces the risk of *** studies have shown extremely low rates of infection following TP prostate biopsies.1,2 Traditionally,TP prostate biopsies have been performed in the operating theater under general or spinal ***,the introduction of the PrecisionPoint Transperineal Access System(Perineologic,Cumberland,MD,USA)facilitates freehand TP prostate biopsies to be performed under local anesthesia(LA).1,2 In this study,we present our initial experience with TP prostate biopsy using the device under LA in an outpatient *** is the first report of TP prostate biopsy under LA in South East Asia.

关键词： anesthesia biopsy perineal

Overcast sky condition prevails on and influences the biometeorology of the tropical Andean Páramos

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Journal of Mountain Science 2023年第1期20卷 78-86页

作者： Paola MONTENEGRO-DÍAZ rolando CELLERIALVEAR Galo CARRILLO-ROJAS Departamento de Recursos Hídricos y Ciencias Ambientales Universidad de CuencaCuenca010207Ecuador Facultad de Ingeniería Universidad de CuencaCuenca010207Ecuador Facultad de Ciencias Químicas Universidad de CuencaCuenca010207Ecuador

Clouds play a major role in modulating the biometeorological processes. We studied the influence of cloudiness on four biometeorological variables:daily air temperature(Tair), relative humidity(RH),reference evapotranspiration(ETr),and photosynthetic active radiation(PAR), recorded at four sites of Andean Páramos in southern Ecuador during 2.5 to 5.5 years. First, we quantified both the cloud cover percentage(Cloud%) creating cloud masks over the visible bands of Landsat 7 images and the sky condition(K_(T)) using the records of solar and extraterrestrial radiation. Second, we estimated KTfrom Cloud%. Finally, we quantified T_(air), RH, ET_(r), and PAR under clear, cloudy, and overcast K_(T) and their dependence on KT. The average Cloud% ranged between 65%–76%, and KTcorroborated the prevailing overcast sky(between 55% and 72.5% of the days) over the páramos. The proposed model performed well in the sites of calibration(R^(2)= 0.80;MBE = 0.00;RMSE = 0.05) and validation(R^(2)= 0.74;MBE =-0.07;RMSE = 0.11). The overcast sky diminished T_(air)(≤ 10℃), ET_(r)(≤ 1.6 mm day-1), and PAR(4 MJ m^(-2)day^(-1)) and increased RH(≥ 88%),while the variables showed the opposite behavior during the uncommon clear sky(≤ 5.5% of the days).Thus, mostly the dynamic of RH(R^(2)≥ 0.62), ETr(R^(2)≥ 0.85), and PAR(R2≥ 0.77) depended on K_(T). Hence,the prevailing overcast sky influenced the biometeorology of the páramos.

关键词： Cloudiness indicator Clearness index Satellite imagery Tropical Andes