Search results for "Computers"
showing 10 items of 3243 documents
Teachers' instructional scaffolding in an innovative information and communication technology-based history learning environment
2002
Abstract The nature of the role assumed by the teacher is crucial in the promotion of successful learning and collaboration in Information and Communication Technologybased (ICT-based) environments. The aim of this study was to examine how teachers with different conceptions of their teacher roles use different types of instructional scaffolding while working in an innovative learning environment. Our further aim was finding out how instructional scaffolding is related to learning activities of different kinds. The study was carried out at two secondary schools with a shared network-based learning environment. The results showed that teachers with different conceptions of the teacher's role…
Low light level in vitro monitoring of cellular and antigen-antibody reactions using a photon detection camera system — New perspectives for clinical…
1990
This article briefly describes the use of a photon counting system (ARGUS-100) in the detection of low levels of light. The ARGUS-100 was used in determining ATP in cell sections from tumor tissues and in measuring a luminescence-enhanced immunoluminometric assay, using ferritin as the analyte, based on the luminol-peroxide-4-iodophenol reaction with peroxidase as the enzyme. The aim is not so much the presentation of data, but rather to show the potentials of the photon counting camera in increasing our knowledge of the cellular and subcellular levels, as well as lowering the detection limits in already sensitive systems, such as immunoassays.
New trends in science education
1996
I intend to review the main contributions from the impressive developments made in science education research during the last decade. These developments have made the construction of a coherent body of knowledge possible allowing us to expect a significant improvement in the science teaching/learning process. I shall refer, in particular, to the new trends in science education research, both in the domain of science learning and science teacher‐training.
Processing of rock core microtomography images: Using seven different machine learning algorithms
2016
The abilities of machine learning algorithms to process X-ray microtomographic rock images were determined. The study focused on the use of unsupervised, supervised, and ensemble clustering techniques, to segment X-ray computer microtomography rock images and to estimate the pore spaces and pore size diameters in the rocks. The unsupervised k-means technique gave the fastest processing time and the supervised least squares support vector machine technique gave the slowest processing time. Multiphase assemblages of solid phases (minerals and finely grained minerals) and the pore phase were found on visual inspection of the images. In general, the accuracy in terms of porosity values and pore…
Managing Human Factors to Reduce Organisational Risk in Industry
2018
[EN] Human factors are intrinsically involved at virtually any level of most industrial/business activities, and may be responsible for several accidents and incidents, if not correctly identified and managed. Focusing on the significance of human behaviour in industry, this article proposes a multi-criteria decision-making (MCDM)-based approach to support organizational risk assessment in industrial environments. The decision-making trial and evaluation laboratory (DEMATEL) method is proposed as a mathematical framework to evaluate mutual relationships within a set of human factors involved in industrial processes, with the aim of highlighting priorities of intervention. A case study relat…
The need for internships and school practices as a method of bridging the gap between education and industry in Romania
2017
Abstract This paper presents the current situation of school practice and internships as ways of reducing the gap between the labor market and education. In the first part, there is highlighted the current situation of Romania comparing with other European countries when it comes about graduates finding a job in their field of studies. Among the biggest issues encountered by a young graduate we see that "Lack of experience” play a big role in not finding a proper job in our country after graduation. So the need to reduce this problem is vital in order to ease finding a job in the studies areas for graduates. A list of advantages is presented to encourage internships/school practice among th…
Imation of land surface emissivity differences in the split-window channels of AVHRR
1994
Abstract A method for estimating the difference between the channel emissivities in NOAA-AVHRR Channels 4 and 5 is proposed and applied to a data set from the HAPEX-MOBILHY experiment. The method is based on the separation between the atmospheric and emissivity effects in the brightness temperature difference measured with AVHRR Channels 4 and 5. Atmospheric profiles coincident to the satellite overpass and a radiative transfer model are required to estimate the atmospheric correction for brightness temperatures. With this procedure, the emissivity difference Δe is obtained at the satellite spatial and spectral resolution, which has a great interest for correcting thermal images with the sp…
L-Band Vegetation optical depth and effective scattering albedo estimation from SMAP
2017
Abstract Over land the vegetation canopy affects the microwave brightness temperature by emission, scattering and attenuation of surface soil emission. Attenuation, as represented by vegetation optical depth (VOD), is a potentially useful ecological indicator. The NASA Soil Moisture Active Passive (SMAP) mission carries significant potential for VOD estimates because of its radio frequency interference mitigation efforts and because the L-band signal penetrates deeper into the vegetation canopy than the higher frequency bands used for many previous VOD retrievals. In this study, we apply the multi-temporal dual-channel retrieval algorithm (MT-DCA) to derive global VOD, soil moisture, and ef…
Roughness and vegetation parameterizations at L-band for soil moisture retrievals over a vineyard field
2015
Abstract The capability of L-band radiometry to monitor surface soil moisture (SM) at global scale has been analyzed in numerous studies, mostly in the framework of the ESA SMOS and NASA SMAP missions. To retrieve SM from L-band radiometric observations, two significant effects have to be accounted for, namely soil roughness and vegetation optical depth. In this study, soil roughness effects on retrieved SM values were evaluated using brightness temperatures acquired by the L-band ELBARA-II radiometer, over a vineyard field at the Valencia Anchor Station (VAS) site during the year 2013. Different combinations of the values of the model parameters used to account for soil roughness effects (…
A generalized soil-adjusted vegetation index
2002
Operational monitoring of vegetative cover by remote sensing currently involves the utilisation of vegetation indices (VIs), most of them being functions of the reflectance in red (R) and near-infrared (NIR) spectral bands. A generalized soil-adjusted vegetation index (GESAVI), theoretically based on a simple vegetation canopy model, is introduced. It is defined in terms of the soil line parameters (A and B) as: GESAVI=(NIRBRA)/(R+Z), where Z is related to the red reflectance at the cross point between the soil line and vegetation isolines. As Z is a soil adjustment coefficient, this new index can be considered as belonging to the SAVI family. In order to analyze the GESAVI sensitivity to s…