Search results for "Cod"
showing 10 items of 2985 documents
Helping lecturers address and formulate teaching challenges: an exploratory study
2018
International audience; In this paper we present an exploratory study on the kind of questions or difficulties lecturers point out at the beginning of an educational course – to be addressed in it. These questions happen to be very general and are poorly connected to the knowledge to be taught. We suggest a twofold interpretation of this phenomenon. On the one hand, and in the line of the didactic transposition theory, teachers do not allow themselves to raise questions about the knowledge that is supposed to be their main field of expertise. On the other hand, the prevailing institutional pedagogy does not provide teachers with a fruitful enough conceptual frame to formulate this kind of q…
Into the wild of long non-coding RNA in gastrointestinal stromal tumors (GISTs) to explore new prognostic/predictive biomarkers
2015
Background: Long Non-coding RNAs (lncRNA) are emerging as essential regulators of genetic and epigenetic networks, and their deregulation may underlie complex diseases, such as carcinogenesis. Several studies have described lncRNAs alterations in patients with solid tumors. In particular, in Gastrointestinal Stromal Tumors (GIST), upregulation of HOTAIR has been associated with aggressiveness, metastasis, and poor patients’ survival. In order to gain more detailed insight on the molecular role of lncRNAs in GIST, we analyzed in vivo the expression levels of lncRNAs H19 and MALAT1 in surgically resected patients. Material and Methods: The expression of the lnc-RNAs H19 and MALAT1 was evaluat…
Validation of a Shear Model for RC and Hybrid Beams with Two Different Inclinations of Transversal Reinforcement
2016
The validation of an analytical model recently proposed for evaluation of the shear capacity in Reinforced Concrete (RC) beams containing multiple inclination of transverse stirrups is presented. The model is a suitable extension of that currently proposed in Eurocode 2 for the evaluation of the shear resistance, and it is derived by means of the the variable-inclination stress-field theory based on Nielsen’s plastic approach. Experimental and numerical data available in the literature on Hybrid Steel-Trussed Concrete Beams (HSTCBs) are used for model validation and result discussion. Finally, also the comparison with a different analytical approach for the assessment of the shear resistanc…
Comparison of Split-Window and Single-Channel Methods for Land Surface Temperature Retrieval from MODIS and AATSR Data
2008
In this study, two different methods for retrieving the Land Surface Temperature (LST) from Terra/Moderate Resolution Imaging Spectroradiometer (MODIS) and Envisat/Advanced Along Track Scanning Radiometer (AATSR) data are compared against a database of ground measured LSTs. These are the split-window (SW) and the single-channel (SC) methods. The SW method expresses LST as a combination of the brightness temperatures in the 11 iquestm and 12 iquestm channels with coefficients that can have local or global validity, depending on the way they are obtained. SC methods are based on the atmospheric radiative transfer equation. To solve this equation, convenient atmospheric temperature and water v…
Further evidence that the effects of repetition on subjective time depend on repetition probability
2017
Repeated stimuli typically have shorter apparent duration than novel stimuli. Most explanations for this effect have attributed it to the repeated stimuli being more expected or predictable than the novel items, but an emerging body of work suggests that repetition and expectation exert distinct effects on time perception. The present experiment replicated a recent study in which the probability of repetition was varied between blocks of trials. As in the previous work, the repetition effect was smaller when repeats were common (and therefore more expected) than when they were rare. These results add to growing evidence that, contrary to traditional accounts, expectation increases apparent …
Three-page encoding and complexity theory for spatial graphs
2004
We construct a series of finitely presented semigroups. The centers of these semigroups encode uniquely up to rigid ambient isotopy in 3-space all non-oriented spatial graphs. This encoding is obtained by using three-page embeddings of graphs into the product of the line with the cone on three points. By exploiting three-page embeddings we introduce the notion of the three-page complexity for spatial graphs. This complexity satisfies the properties of finiteness and additivity under natural operations.
Positioning system for assembly and manufacturing tasks
2019
The paper presents a two-axis positioning system using asynchronous motors as actuation devices. Theuse of asynchronous motors reduces the overall cost of the system, while providing actuating torques superior to the ones provided by stepping motors. The system is controlled by mean of a programmable logic controller (PLC) and two voltage-frequency inverters fitted with motion control cards. In contrasts to a stepping motor system, which works in open loop mode, the proposed system uses closed loop control on each axis. The motion loop is closed by means of an incremental encoder.
Text Compression Using Antidictionaries
1999
International audience; We give a new text compression scheme based on Forbidden Words ("antidictionary"). We prove that our algorithms attain the entropy for balanced binary sources. They run in linear time. Moreover, one of the main advantages of this approach is that it produces very fast decompressors. A second advantage is a synchronization property that is helpful to search compressed data and allows parallel compression. Our algorithms can also be presented as "compilers" that create compressors dedicated to any previously fixed source. The techniques used in this paper are from Information Theory and Finite Automata.
Time multiplexing super-resolved imaging without a priori knowledge of the spatial distribution of the encoding structured illumination
2021
Time multiplexing is a super-resolution technique that sacrifices time to overcome the resolution reduction obtained because of diffraction. There are many super resolution methods based on time multiplexing, but all of them require a priori knowledge of the time changing encoding mask, which is projected on the object and used to encode and decode the high-resolution information. In this paper, we present a time multiplexing technique that does not require the a priori knowledge on the projected encoding mask. First, the theoretical concept of the technique is demonstrated; then, numerical simulations and experimental results are presented.
A limited feedback scheme based on spatially correlated channels for coordinated multipoint systems
2012
High spectral efficiency can be achieved in the downlink of multi-antenna coordinated multi-point systems provided that the multiuser interference is appropriately managed at the transmitter side. For this sake, downlink channel information needs to be sent back by the users, thus reducing the rate available at the uplink channel. The amount and type of feedback information required has been extensively studied and many limited feedback schemes have been proposed lately. A common pattern to all of them is that achieving low rates of feedback information is possible at the cost of increasing complexity at the user side and, sometimes, assuming that some statistics of the channel are known. I…