941 research outputs found
THE FARMHOUSES OF THE ROMAN COUNTRYSIDE: CENSUS AND CATALOG. THE CASE OF THE ESTATE OF FARNESIANA
Abstract. Rome is one of the cities with the largest green areas in the world, spread in villas and estates, within the municipal territory. But there is also a landscape triangle that radially branches out from the historic center, including a variety of unique situations (archaeological, historical – social, settlement, agriculture ...) in the world: the Caffarella and aqueducts Park. Inside, the Farnesiana estate, Capo di Bove, it's a witness of a widespread degradation process in the Roman countryside, which requires a gradual procedure of knowledge, cataloguing, restoration and re-functioning of the historical heritage. In this regard, the research is part of a larger study project of the Department of Architecture of Roma Tre, concerning farmhouses of the Roman countryside that deal with worrying degradation conditions and which require imminent intervention.</p
Influence of natural surfactants on short wind waves in the coastal Peruvian waters
Results from measurements of wave slope statistics during the R/V Meteor M91 cruise in the coastal upwelling regions off the coast of Peru are reported. Wave slope probability distributions were measured with an instrument based on the reflection of light at the water surface and a method very similar to the Cox and Munk (1954b) sun glitter technique. During the cruise, the mean square slope (mss) of the waves was found to be very variable, despite the limited range of encountered wind speeds. The Cox and Munk (1954b) parameterization for clean water is found to overestimate mss, but most measurements fall in the range spanned by their clean water and slick parameterizations. The observed variability of mss is attributed to the wave damping effect of surface films, generated by increased biological production in the upwelling zones. The small footprint and high temporal resolution of the measurement allows for tracking abrupt changes in conditions caused by the often patchy structure of the surface films
Zinc Oxide Nanowires Deposited on Polymeric Hotplates for Low-power Gas Sensors
Zinc oxides (ZnO) nanowires were successfully deposited on plastic low-power micro-hotplates using the thermal oxidation technique. Metallic zinc layer was deposited on the sensing transducer by RF magnetron sputtering and then oxidized in a controlled atmosphere in order to obtain ZnO nanostructures. Morphological investigations confirmed the nanometric dimensions of the fabricated nanostructures. The n-type behavior of the nanostructured material was evaluated towards different chemical species to highlight the electrical properties of the materials. Calibration curves for the detection of several chemical species were defined. © 2012 The Authors. Published by Elsevier Ltd
Detection of microbial contamination in potable water by Nanowire technology
It is well known that the lack of control and sanitation of water in developing countries has cause very significant epidemiological events. In the last decades the situation of water supplies and sanitation has improve all over the world. Despite of it, in the European Union there are a considerable number of confirmed cases of water-borne infections even though the restrictive law. Electronic Noses (ENs) has shown to be a very effective and fast tool for monitoring microbiological spoilage and quality control. The aim of this study was test the ability of a novel EN for the detection of bacterial presence in potable water in cooperation with analytical (pH) and optical (photometer) techniques. The achieved results notably advocate the use of EN in industry laboratories as a very important tool in water quality control
Confidence Regions for Multivariate Calibration: a proposal
Most of the papers on calibration are based on either classic or bayesian parametric context. In addition to the typical problems of the parametric approach
(choice of the distribution for the measurement errors, choice of the model that links the sets of variables, etc.), a relevant problem in calibration is the construction of confidence region for the unknown levels of the explanatory variables. In this paper we propose a semiparametric approach, based on simplicia1 depth, to test the hypothesis of linearity of the link function and then how to find calibration
depth confidence regions
A Parameter Model of Gas Exchange for the Seasonal Sea Ice Zone
Carbon budgets for the polar oceans require better constraint on air–sea gas exchange in the sea ice zone (SIZ). Here, we utilize advances in the theory of turbulence, mixing and air–sea flux in the ice–ocean boundary layer (IOBL) to formulate a simple model for gas exchange when the surface ocean is partially covered by sea ice. The gas transfer velocity (k) is related to shear-driven and convection-driven turbulence in the aqueous mass boundary layer, and to the mean-squared wave slope at the air–sea interface. We use the model to estimate k along the drift track of ice-tethered profilers (ITPs) in the Arctic. Individual estimates of daily-averaged k from ITP drifts ranged between 1.1 and 22 m d−1, and the fraction of open water (f) ranged from 0 to 0.83. Converted to area-weighted effective transfer velocities (keff), the minimum value of keff was 10−55 m d−1 near f = 0 with values exceeding keff = 5 m d−1 at f = 0.4. The model indicates that effects from shear and convection in the sea ice zone contribute an additional 40% to the magnitude of keff, beyond what would be predicted from an estimate of keff based solely upon a wind speed parameterization. Although the ultimate scaling relationship for gas exchange in the sea ice zone will require validation in laboratory and field studies, the basic parameter model described here demonstrates that it is feasible to formulate estimates of k based upon properties of the IOBL using data sources that presently exist
Human Papillomavirus (HPV) infection and genotype frequency in the oral mucosa of newborns in Milan, Italy
Human papillomavirus (HPV) causes cutaneous and mucosal infections in both adults and children. In order to evaluate HPV prevalence and the spectrum of genotypes in the oral cavity of paediatric subjects, a retrospective study was carried out on oral-pharyngeal swabs collected from 177 newborns aged 0-6months. HPV-DNA was detected by a nested-PCR; the viral typing was made through DNA sequencing. HPV infection was identified in 25 subjects (14.1%) and the sequence analysis showed eight distinct genotypes. These data confirm HPV detection in newborn oral mucosa. Further investigations are needed to clarify the methods of HPV acquisition
Analog SiPM in Planar CMOS Technology
Silicon Photomultipliers (SiPMs) are emerging single photon detectors used in many applications requiring large active area, photon number resolving capability and immunity to magnetic fields. We developed planar analog SiPMs in a reliable and cost-effective CMOS technology with a total photosensitive area of about 1×1 mm2. Three devices with different active areas, and fill-factor (21%, 58.3%, 73.7%), have been characterized. The maximum photon detection efficiency is in the near-UV and tops at 38% (fill-factor included), with a dark count rate of 125 kcps. Gain and crosstalk depend on the active area size and are comparable to those of commercial best-in-class custom-technology SiPMs. However our full CMOS processing enables advanced SiPM single-chip systems where transistors and further on chip electronics can be integrated together with the detectors
SPADAS: A high-speed 3D single-photon camera for advanced driver assistance systems
Advanced Driver Assistance Systems (ADAS) are the most advanced technologies to fight road accidents. Within ADAS, an important role is played by radar- and lidar-based sensors, which are mostly employed for collision avoidance and adaptive cruise control. Nonetheless, they have a narrow field-of-view and a limited ability to detect and differentiate objects. Standard camera-based technologies (e.g. stereovision) could balance these weaknesses, but they are currently not able to fulfill all automotive requirements (distance range, accuracy, acquisition speed, and frame-rate). To this purpose, we developed an automotive-oriented CMOS single-photon camera for optical 3D ranging based on indirect time-of-flight (iTOF) measurements. Imagers based on Single-photon avalanche diode (SPAD) arrays offer higher sensitivity with respect to CCD/CMOS rangefinders, have inherent better time resolution, higher accuracy and better linearity. Moreover, iTOF requires neither high bandwidth electronics nor short-pulsed lasers, hence allowing the development of cost-effective systems. The CMOS SPAD sensor is based on 64 × 32 pixels, each able to process both 2D intensity-data and 3D depth-ranging information, with background suppression. Pixel-level memories allow fully parallel imaging and prevents motion artefacts (skew, wobble, motion blur) and partial exposure effects, which otherwise would hinder the detection of fast moving objects. The camera is housed in an aluminum case supporting a 12 mm F/1.4 C-mount imaging lens, with a 40°×20° field-of-view. The whole system is very rugged and compact and a perfect solution for vehicle’s cockpit, with dimensions of 80 mm × 45 mm × 70 mm, and less that 1 W consumption. To provide the required optical power (1.5 W, eye safe) and to allow fast (up to 25 MHz) modulation of the active illumination, we developed a modular laser source, based on five laser driver cards, with three 808 nm lasers each. We present the full characterization of the 3D automotive system, operated both at night and during daytime, in both indoor and outdoor, in real traffic, scenario. The achieved long-range (up to 45m), high dynamic-range (118 dB), highspeed (over 200 fps) 3D depth measurement, and high precision (better than 90 cm at 45 m), highlight the excellent performance of this CMOS SPAD camera for automotive applications. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only
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