908 resultados para open-water evaporation radiation-based models


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Pós-graduação em Educação Sexual - FCLAR

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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

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There are several researches on evaluation of urban public space, but not all establish a relationship between the configuration of spaces with the thermal environment, ergonomics and environmental behavior of users. To understand this relationship, the aim of this paper is to present the model DEPAN (Design for Permanence and Attractiveness in niches open spaces of conviviality), based on graphical meshes, which were designed to evaluate the influence of design and ergonomics of open public spaces in the human thermal comfort and the ways in which users appropriate the space. Its applicability is demonstrated through a case study conducted in a park in the city of Bauru-SP. To perform this evaluation public space niches were chosen. They were formed by morphological elements and street furniture and defined by their spatial arrangements. The collected data were incorporated into a Geographic Information System (GIS), which allowed the overlay of meshes. The results indicate that the DEPAN model allows the verification of the spatial characteristics, thermal quality and ergonomic design generated by spaces, as well as the evaluation of the influence of these aspects in the way of using the spaces. The model allows the generation of a classification for every niche and set a value for the level of service offered.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fresh-water diatoms are present in coal, and tonsteins (altered volcanic ash) are interbedded with the coal, in the Miocene Venado Formation on the southwest margin of the Limon Basin, in Provincia Alajuela, northern Costa Rica. The Venado Formation is composed of more than 300 m of mudstone, siltstone, sandstone, limestone, volcaniclastics, and coal beds. The coal beds are of unknown lateral extent and mainly occur in the middle part of the formation. The Pataste coal bed occurs near the middle of the formation and is divided into three parts by two tonstein layers. The abundance of biogenic opaline material (diatoms) in the coal is believed to be a direct response to an influx of silica from volcanic tuffs that Later altered to the tonsteins. Diatoms are a useful microscopic tool for identifying the depositional environments of the Pataste coal deposit. The diatoms identified include Aulacosira ambigua, Pinnularia sp., Eunotia spp., and Achnanthes exigua, among others. The abundance of Aulacosira arnbigua suggests that an open-water lacustrine environment was present locally. Achnanthes exigua and the remaining diatom species are benthic forms that lived in shallow fresh-water to slightly acidic swamp environments. The different types of diatoms found in the coal indicate that swamp environments were intermixed with lacustrine environments during the formation of the peat deposit or that the coal records environmental changes through time.

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Park Service Thwarts Cat Allies, by Marilyn Davis, Native Species Network, Bodega Bay, California Jim Miller Elected VP of Wildlife Society ADC Aerial Hunting Accident Kills 2 Obituary: Carl R. Gustavson HSUS Former Employee File Lawsuits Rats Shut Down Internet at Stanford Call for Papers: A Symposium on Mammal Trapping August 1997 in Edmonton, Alberta Fur in Cyberspace: The Fur Institute of Canada announces it has established a site on the World Wide Web, at the following address: http://www.fur.ca. Book Review: Beaver and Otter: Open Water Techniques, by Charles Dobbins 1992. Beaver Pond Publishing and Printing, P.O. Box 224, Greenville, Pennsyulvania, 16125. 114 pages. American Association of Wildlife Veterinarians: Resolution on Management of Feral Cats Use of Zinc Phosphide for Marmot Control, by Mark Collinge, NADCA Northern Rockies Region Director, USDA-APHIS-ADC Cat Colony Ordinance Adopted by Santa Clara County, California

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This paper presents further results from our spectroscopic study of the globular cluster (GC) system of the group elliptical NGC 3923. From observations made with the GMOS instrument on the Gemini South Telescope, an additional 50 GC and ultra-compact dwarf (UCD) candidates have been spectroscopically confirmed as members of the NGC 3923 system. When the recessional velocities of these GCs are combined with the 29 GC velocities reported previously, a total sample of 79 GC/UCD velocities is produced. This sample extends to over 6 arcmin (>6 R-e similar to 30 kpc) from the centre of NGC 3923 and is used to study the dynamics of the GC system and the dark matter content of NGC 3923. It is found that the GC system of NGC 3923 displays no appreciable rotation, and that the projected velocity dispersion is constant with radius within the uncertainties. The velocity dispersion profiles of the integrated light and GC system of NGC 3923 are indistinguishable over the region in which they overlap. We find some evidence that the diffuse light and GCs of NGC 3923 have radially biased orbits within similar to 130 arcsec. The application of axisymmetric orbit-based models to the GC and integrated light velocity dispersion profiles demonstrates that a significant increase in the mass-to-light ratio (from M/L-V = 8 to 26) at large galactocentric radii is required to explain this observation. We therefore confirm the presence of a dark matter halo in NGC 3923. We find that dark matter comprises 17.5(-4.5)(+7.3) per cent of the mass within 1 R-e, 41.2(-10.6)(+18.2) per cent within 2 R-e and 75.6(-16.8)(+15.4) per cent within the radius of our last kinematic tracer at 6.9 R-e. The total dynamical mass within this radius is found to be 1.5(-0.25)(+0.4) x 10(12) M-circle dot. In common with other studies of large ellipticals, we find that our derived dynamical mass profile is consistently higher than that derived by X-ray observations, by a factor of around 2.

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1. A long-standing question in ecology is how natural populations respond to a changing environment. Emergent optimal foraging theory-based models for individual variation go beyond the population level and predict how its individuals would respond to disturbances that produce changes in resource availability. 2. Evaluating variations in resource use patterns at the intrapopulation level in wild populations under changing environmental conditions would allow to further advance in the research on foraging ecology and evolution by gaining a better idea of the underlying mechanisms explaining trophic diversity. 3. In this study, we use a large spatio-temporal scale data set (western continental Europe, 19682006) on the diet of Bonellis Eagle Aquila fasciata breeding pairs to analyse the predator trophic responses at the intrapopulation level to a prey population crash. In particular, we borrow metrics from studies on network structure and intrapopulation variation to understand how an emerging infectious disease [the rabbit haemorrhagic disease (RHD)] that caused the density of the eagles primary prey (rabbit Oryctolagus cuniculus) to dramatically drop across Europe impacted on resource use patterns of this endangered raptor. 4. Following the major RHD outbreak, substantial changes in Bonellis Eagles diet diversity and organisation patterns at the intrapopulation level took place. Dietary variation among breeding pairs was larger after than before the outbreak. Before RHD, there were no clusters of pairs with similar diets, but significant clustering emerged after RHD. Moreover, diets at the pair level presented a nested pattern before RHD, but not after. 5. Here, we reveal how intrapopulation patterns of resource use can quantitatively and qualitatively vary, given drastic changes in resource availability. 6. For the first time, we show that a pathogen of a prey species can indirectly impact the intrapopulation patterns of resource use of an endangered predator.

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Air Pollution and Health: Bridging the Gap from Sources to Health Outcomes, an international specialty conference sponsored by the American Association for Aerosol Research, was held to address key uncertainties in our understanding of adverse health effects related to air pollution and to integrate and disseminate results from recent scientific studies that cut across a range of air pollution-related disciplines. The Conference addressed the science of air pollution and health within a multipollutant framework (herein "multipollutant" refers to gases and particulate matter mass, components, and physical properties), focusing on five key science areas: sources, atmospheric sciences, exposure, dose, and health effects. Eight key policy-relevant science questions integrated across various parts of the five science areas and a ninth question regarding findings that provide policy-relevant insights served as the framework for the meeting. Results synthesized from this Conference provide new evidence, reaffirm past findings, and offer guidance for future research efforts that will continue to incrementally advance the science required for reducing uncertainties in linking sources, air pollutants, human exposure, and health effects. This paper summarizes the Conference findings organized around the science questions. A number of key points emerged from the Conference findings. First, there is a need for greater focus on multipollutant science and management approaches that include more direct studies of the mixture of pollutants from sources with an emphasis on health studies at ambient concentrations. Further, a number of research groups reaffirmed a need for better understanding of biological mechanisms and apparent associations of various health effects with components of particulate matter (PM), such as elemental carbon, certain organic species, ultrafine particles, and certain trace elements such as Ni, V, and Fe(II), as well as some gaseous pollutants. Although much debate continues in this area, generation of reactive oxygen species induced by these and other species present in air pollution and the resulting oxidative stress and inflammation were reiterated as key pathways leading to respiratory and cardiovascular outcomes. The Conference also underscored significant advances in understanding the susceptibility of populations, including the role of genetics and epigenetics and the influence of socioeconomic and other confounding factors and their synergistic interactions with air pollutants. Participants also pointed out that short-and long-term intervention episodes that reduce pollution from sources and improve air quality continue to indicate that when pollution decreases so do reported adverse health effects. In the limited number of cases where specific sources or PM2.5 species were included in investigations, specific species are often associated with the decrease in effects. Other recent advances for improved exposure estimates for epidemiological studies included using new technologies such as microsensors combined with cell phone and integrated into real-time communications, hybrid air quality modeling such as combined receptor-and emission-based models, and surface observations used with remote sensing such as satellite data.

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Groundwater has a strategic role in times of climate change mainly because aquifers can provide water for long periods, even during very long and severe drought. The reduction and/or changes on the precipitation pattern can diminish the recharge mainly in unconfined aquifer, causing available groundwater restriction. The expected impact of long-term climate changes on the Brazilian aquifers for 2050 will lead to a severe reduction in 70% of recharge in the Northeast region aquifers (comparing to 2010 values), varying from 30% to 70% in the North region. Data referring to the South and Southeast regions are more favorable, with an increase in the relative recharge values from 30% to 100%. Another expected impact is the increase in demand and the decrease in the surface water availability that will make the population turn to aquifers as its main source of water for public or private uses in many regions of the country. Thus, an integrated use of surface and groundwater must therefore be considered in the water use planning. The solution of water scarcity is based on three factors: society growth awareness, better knowledge on the characteristics of hydraulic and chemical aquifers and effective management actions.

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Among various nanoparticles, noble metal nanoparticles have attracted considerable attention due to their optical, catalytic and conducting properties. This work has been focused on the development of an innovative method of synthesis for the preparation of metal nanosuspensions of Au, Ag, Cu, in order to achieve stable sols, showing suitable features to allow an industrial scale up of the processes. The research was developed in collaboration with a company interested in the large scale production of the studied nanosuspensions. In order to develop a commercial process, high solid concentration, long time colloidal stability and particle size control, are required. Two synthesis routes, differing by the used solvents, have been implemented: polyol based and water based synthesis. In order to achieve a process intensification the microwave heating has been applied. As a result, colloidal nanosuspensions with suitable dimensions, good optical properties, very high solid content and good stability, have been synthesized by simple and environmental friendly methods. Particularly, due to some interesting results an optimized synthesis process has been patented. Both water and polyol based synthesis, developed in the presence of a reducing agent and of a chelating polymer, allowed to obtain particle size-control and colloidal stability by tuning the different parameters. Furthermore, it has been verified that microwave device, due to its rapid and homogeneous heating, provides some advantages over conventional method. In order to optimize the final suspensions properties, for each synthesis it has been studied the effect of different parameters (temperature, time, precursors concentrations, etc) and throughout a specific optimization action a right control on nucleation and growth processes has been achieved. The achieved nanoparticles were confirmed by XRD analysis to be the desired metal phases, even at the lowest synthesis temperatures. The particles showed a diameter, measured by STEM and dynamic light scattering technique (DLS), ranging from 10 to 60 nm. Surface plasmon resonance (SPR) was monitored by UV-VIS spectroscopy confirming its dependence by nanoparticles size and shape. Moreover the reaction yield has been assessed by ICP analysis performed on the unreacted metal cations. Finally, thermal conductivity and antibacterial activity characterizations of copper and silver sols respectively are now ongoing in order to check their application as nanofluid in heat transfer processes and as antibacterial agent.

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The present work concerns with the study of debris flows and, in particular, with the related hazard in the Alpine Environment. During the last years several methodologies have been developed to evaluate hazard associated to such a complex phenomenon, whose velocity, impacting force and inappropriate temporal prediction are responsible of the related high hazard level. This research focuses its attention on the depositional phase of debris flows through the application of a numerical model (DFlowz), and on hazard evaluation related to watersheds morphometric, morphological and geological characterization. The main aims are to test the validity of DFlowz simulations and assess sources of errors in order to understand how the empirical uncertainties influence the predictions; on the other side the research concerns with the possibility of performing hazard analysis starting from the identification of susceptible debris flow catchments and definition of their activity level. 25 well documented debris flow events have been back analyzed with the model DFlowz (Berti and Simoni, 2007): derived form the implementation of the empirical relations between event volume and planimetric and cross section inundated areas, the code allows to delineate areas affected by an event by taking into account information about volume, preferential flow path and digital elevation model (DEM) of fan area. The analysis uses an objective methodology for evaluating the accuracy of the prediction and involve the calibration of the model based on factors describing the uncertainty associated to the semi empirical relationships. The general assumptions on which the model is based have been verified although the predictive capabilities are influenced by the uncertainties of the empirical scaling relationships, which have to be necessarily taken into account and depend mostly on errors concerning deposited volume estimation. In addition, in order to test prediction capabilities of physical-based models, some events have been simulated through the use of RAMMS (RApid Mass MovementS). The model, which has been developed by the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) in Birmensdorf and the Swiss Federal Institute for Snow and Avalanche Research (SLF) takes into account a one-phase approach based on Voellmy rheology (Voellmy, 1955; Salm et al., 1990). The input file combines the total volume of the debris flow located in a release area with a mean depth. The model predicts the affected area, the maximum depth and the flow velocity in each cell of the input DTM. Relatively to hazard analysis related to watersheds characterization, the database collected by the Alto Adige Province represents an opportunity to examine debris-flow sediment dynamics at the regional scale and analyze lithologic controls. With the aim of advancing current understandings about debris flow, this study focuses on 82 events in order to characterize the topographic conditions associated with their initiation , transportation and deposition, seasonal patterns of occurrence and examine the role played by bedrock geology on sediment transfer.

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In this thesis I present theoretical and experimental results concern- ing the operation and properties of a new kind of Penning trap, the planar trap. It consists of circular electrodes printed on an isolating surface, with an homogeneous magnetic field pointing perpendicular to that surface. The motivation of such geometry is to be found in the construction of an array of planar traps for quantum informa- tional purposes. The open access to radiation of this geometry, and the long coherence times expected for Penning traps, make the planar trap a good candidate for quantum computation. Several proposals for quantum 2-qubit interactions are studied and estimates for their rates are given. An expression for the electrostatic potential is presented, and its fea- tures exposed. A detailed study of the anharmonicity of the potential is given theoretically and is later demonstrated by experiment and numerical simulations, showing good agreement. Size scalability of this trap has been studied by replacing the original planar trap by a trap twice smaller in the experimental setup. This substitution shows no scale effect apart from those expected for the scaling of the parameters of the trap. A smaller lifetime for trapped electrons is seen for this smaller trap, but is clearly matched to a bigger misalignment of the trap’s surface and the magnetic field, due to its more difficult hand manipulation. I also give a hint that this trap may be of help in studying non-linear dynamics for a sextupolarly perturbed Penning trap.

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TuCSoN (Tuple Centres Spread over the Network) è un modello di coordinazione per processi distribuiti o agenti autonomi. Il modello di TuCSoN viene implementato come un middleware distribuito Java-based, distribuito Open Source sotto la licenza LGPL tramite Googlecode. Il fatto che lo stesso sia Open Source e Java-based ha reso possibile il suo porting su Android, rendendo il noto sistema operativo di Google un possibile agente partecipante ad un sistema TuCSoN. La tesi descrive il percorso che ha portato dallo studio dell'infrastruttura TuCSoN e del sistema Android alla realizzazione dell'applicazione Android, rendendo possibile a qualsiasi dispositivo Android di partecipare ad un sistema TuCSoN. Nel particolare l'obiettivo finale dell'applicazione Android, e di questa tesi, è rendere lo smartphone un nodo TuCSoN funzionante. La tesi non si pone l'obiettivo di analizzare ed esplorare le funzionalità e le possibilitàa delle due tecnologie principali trattate (Android e TuCSoN) nel loro singolo, quanto quello di esplorare le criticità che un porting di questo tipo comporta, quali ad esempio le differenze intrinseche fra la JVM e la DalvikVM e come aggirarle, o le funzionalità di Android e come utilizzarle allo scopo di realizzare un applicazione che funga da server ad una infra- struttura distribuita, oppure le differenze a livello di gestione della GUI fra Android e plain-java, e di analizzare le soluzioni trovate per risolvere (o dove non era possibile risolvere evitare) tali problemi al fine del raggiungimento dell'obiettivo che ci si era prefissati.

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Questa tesi di dottorato è inserita nell’ambito della convenzione tra ARPA_SIMC (che è l’Ente finanziatore), l’Agenzia Regionale di Protezione Civile ed il Dipartimento di Scienze della Terra e Geologico - Ambientali dell’Ateneo di Bologna. L’obiettivo principale è la determinazione di possibili soglie pluviometriche di innesco per i fenomeni franosi in Emilia Romagna che possano essere utilizzate come strumento di supporto previsionale in sala operativa di Protezione Civile. In un contesto geologico così complesso, un approccio empirico tradizionale non è sufficiente per discriminare in modo univoco tra eventi meteo innescanti e non, ed in generale la distribuzione dei dati appare troppo dispersa per poter tracciare una soglia statisticamente significativa. È stato quindi deciso di applicare il rigoroso approccio statistico Bayesiano, innovativo poiché calcola la probabilità di frana dato un certo evento di pioggia (P(A|B)) , considerando non solo le precipitazioni innescanti frane (quindi la probabilità condizionata di avere un certo evento di precipitazione data l’occorrenza di frana, P(B|A)), ma anche le precipitazioni non innescanti (quindi la probabilità a priori di un evento di pioggia, P(A)). L’approccio Bayesiano è stato applicato all’intervallo temporale compreso tra il 1939 ed il 2009. Le isolinee di probabilità ottenute minimizzano i falsi allarmi e sono facilmente implementabili in un sistema di allertamento regionale, ma possono presentare limiti previsionali per fenomeni non rappresentati nel dataset storico o che avvengono in condizioni anomale. Ne sono esempio le frane superficiali con evoluzione in debris flows, estremamente rare negli ultimi 70 anni, ma con frequenza recentemente in aumento. Si è cercato di affrontare questo problema testando la variabilità previsionale di alcuni modelli fisicamente basati appositamente sviluppati a questo scopo, tra cui X – SLIP (Montrasio et al., 1998), SHALSTAB (SHALlow STABility model, Montgomery & Dietrich, 1994), Iverson (2000), TRIGRS 1.0 (Baum et al., 2002), TRIGRS 2.0 (Baum et al., 2008).