Search results for "Content"

Machine Learning Methods for One-Session Ahead Prediction of Accesses to Page Categories

2004

This paper presents a comparison among several well-known machine learning techniques when they are used to carry out a one-session ahead prediction of page categories. We use records belonging to 18 different categories accessed by users on the citizen web portal Infoville XXI. Our first approach is focused on predicting the frequency of accesses (normalized to the unity) corresponding to the user’s next session. We have utilized Associative Memories (AMs), Classification and Regression Trees (CARTs), Multilayer Perceptrons (MLPs), and Support Vector Machines (SVMs). The Success Ratio (SR) averaged over all services is higher than 80% using any of these techniques. Nevertheless, given the …

Effects of organic aerosol constituents on extinction and absorption coefficients and liquid water contents of fogs and clouds

1978

We have speculated on the influence of organic material on extinction and absorption coefficients and liquid water content of fogs and of clouds immediately after their condensational stage. It results therefore, that the reduction of the speed of growth from fog to cloud droplets due to the presence of organic films largely reduces the properties mentioned. Compared to that their increase coming from the surface tension reduction due to organic material being dissolved or building up films is expected to be less effective.

Media Effects: Levels of Analysis

2017

Bibliometric analysis and literature review of ecotourism: Toward sustainable development

2021

In recent decades, rising consumer interest in visiting relatively less commercialized natural destinations has facilitated the growth of ecotourism. Yet the research on ecotourism is fragmented, presenting gaps in the current understanding of this topic. This study performs a bibliometric analysis to assimilate the present knowledge from a total of 878 articles published in six reputable outlets between 1990 and 2019. The study analyzed citation chains and coauthorship networks to acknowledge contributions from select authors, organizations, and countries. Next, a cocitation analysis of the prior literature identified four major thematic areas: ecological preservation, residents' interests…

The European Flag According to Paolo Fabbri

2021

Too often we consider symbols in our cultures to be indivisible monoliths that can only be interpreted through the connotations they take on over time. This is due, on one hand, to their compact nature, the correspondence between the planes of expression and content that make them appear solid, impossible to break down. However, it is also true that in the majority of cases we inherit ready-made symbols that seem to have been born with their current shape, with no hint as to the processes that have made them this way. As a rule, there are so many, varied meanings of the word “symbol” that, in the absence of a clear, consensual hypothesis on what a symbol is, they can be difficult to read. A…

The Content of the Websites: Emergence of Intimate Cyberplaces

2017

On the basis of an interpretation of the content of the contrade’s websites, this chapter proposes that these communities unlock cyberspace through inhabiting cyberplaces. They local ise cyberspace, making it concrete and create intimacy by highlighting their history, special places, and maps of their district, announcing events and posting pictures of them, presenting and explaining their symbol ism, exhibiting emblems and artefacts, and by listing the names and showing pictures of community members and horses that have taken part in the palio. By constructing websites in such a way, the contrade inhabit cyberplaces that are characterised by intimacy and familiarity , as they present their…

In Situ X-Ray Tomography Imaging of Soil Water and Cyanobacteria From Biological Soil Crusts Undergoing Desiccation

2018

Biological soil crusts (biocrusts) are millimeter-sized microbial communities developing on the topsoils of arid lands that cover some 12% of Earth’s continental area. Biocrusts consist of an assemblage of mineral soil particles consolidated into a crust by microbial organic polymeric substances that are mainly produced by the filamentous bundle-forming cyanobacteria, among which Microcoleus vaginatus is perhaps the most widespread. This cyanobacterium is the primary producer for, and main architect of biocrusts in many arid soils, sustaining the development of a diverse microbial community. Biocrusts are only active when wet, and spend most of their time in a state of desiccated quiescence…

A semi-empirical approach for surface soil water content estimation from radar data without a-priori information on surface roughness

2006

Abstract In this study, the spatial distribution of soil water content in an agricultural area of 30 km 2 in Southern Italy has been estimated by using high-resolution space-borne Synthetic Aperture Radar data. Multi-polarised SAR images acquired during the SIR-C mission in April 1994 have been analysed by using the semi-empirical surface backscattering model derived by Oh, Y., Sarabandi K., Ulaby F.T., 1992. An empirical model and an inversion technique for radar scattering from bare soil surface. IEEE Trans. Geosci. Remote Sensing, 30(2), 370381. A site-specific calibration procedure of the cited model has been proposed to derive soil dielectric constant values without a-priori informatio…

Surface Soil Moisture Retrieval Using the L-Band Synthetic Aperture Radar Onboard the Soil Moisture Active–Passive Satellite and Evaluation at Core V…

2017

This paper evaluates the retrieval of soil moisture in the top 5-cm layer at 3-km spatial resolution using L-band dual-copolarized Soil Moisture Active–Passive (SMAP) synthetic aperture radar (SAR) data that mapped the globe every three days from mid-April to early July, 2015. Surface soil moisture retrievals using radar observations have been challenging in the past due to complicating factors of surface roughness and vegetation scattering. Here, physically based forward models of radar scattering for individual vegetation types are inverted using a time-series approach to retrieve soil moisture while correcting for the effects of static roughness and dynamic vegetation. Compared with the …

A RADARSAT-2 Quad-Polarized Time Series for Monitoring Crop and Soil Conditions in Barrax, Spain

2012

An analysis of the sensitivity of synthetic aperture radar (SAR) backscatter (σo) to crop and soil conditions was conducted using 57 RADARSAT-2 C-band quad-polarized SAR images acquired from April to September 2009 for large fields of wheat, barley, oat, corn, onion, and alfalfa in Barrax, Spain. Preliminary results showed that the cross-polarized σHVo was particularly useful for monitoring both crop and soil conditions and was the least sensitive to differences in beam incidence angle. The greatest separability of barley, corn, and onion occurred in spring after the barley had been harvested or in the narrow time window associated with grain crop heading when corn and onion were still imma…