Search results for " code"
showing 10 items of 636 documents
Image simulation of geostationary sensor dedicated to ocean color
2010
A method of image simulation of geostationary sensor dedicated to ocean color for open water (case1) and coastal water (case2) is presented in this paper. This method uses HYDROLIGHT to model the radiative transfer in order to obtain the water surface radiance. MeRIS level 3 products have been used for input water components to provide a realistic spatial distribution. The atmospheric radiative transfer model and the sensor model finely lead to satellite remote sensing images. This system allows to evaluate the dynamic range of BOA and TOA radiances depending on solar and viewing angles in operational situation and latter their influence on water composition retrieval.
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…
Privacy enhanced mutual authentication in LTE
2013
In this paper we propose a way to enhance the identity privacy in LTE/LTE-Advanced systems. This is achieved while minimizing the impact on the existing E-UTRAN system. This is important since proposals to modify a widely deployed infrastructure must be cost effective, both in terms of design changes and in terms of deployment cost. In our proposal, the user equipment (UE) identifies itself with a dummy identity, consisting only of the mobile nation code and the mobile network code. We use the existing signalling mechanisms in a novel way to request a special encrypted identity information element. This element is protected using identity-based encryption (IBE), with the home network (HPLMN…
Automorphisms of Hyperelliptic GAG-codes
2008
In this talk, we discuss the n-automorphism groups of generalized algebraic-geometry codes associated with rational, elliptic and hyperelliptic function fields. Such groups are, up to isomorphism, subgroups of the automorphism groups of the underlying function fields. We also present some examples in which the n-automorphism groups can be determined explicitly.
Using coded excitation to maintain signal to noise for FMC+TFM on attenuating materials
2019
Ultrasonic Non-Destructive Evaluation using Full Matrix Capture (FMC) and Total Focusing Method (TFM) is used for high resolution imaging as every pixel is in optimal focus. FMC excites one element in turn, so operates with lower transmitted energy compared to phased array beamforming. The energy at a reflector is further reduced by the broad directivity pattern of the single element. The large number of Tx/Rx A-scans that contribute to each pixel recover the Signal-to-Noise Ratio (SNR) in the final TFM image. Maintaining this in the presence of attenuating materials is a challenge because relevant information in each A-scan signal is buried in the thermal noise, and the TFM process assumes…
Regulatory factor for the transcription of the ribosomal genes in amphibian oocytes.
1970
AMPHIBIAN oocytes provide very convenient material for the study of the mechanisms that control ribosomal RNA synthesis because their pattern of ribosomal RNA synthesis does not change greatly during oogenesis. During the lampbrush stage of oogenesis (stage 4) more than 97 per cent of the RNA synthesized per unit time in the oocytes is ribosomal. This happens because the genes for ribosomal RNA are specifically amplified3–5 to such an extent that the oocyte nucleus (germinal vesicle) has an rDNA content approximately 1,500 times more than the haploid amount4. On the other hand, in mature oocytes (stage 6) no ribosomal RNA is synthesized1,2, although the extra copies of the ribosomal cistron…
Novel Iris Biometric Watermarking Based on Singular Value Decomposition and Discrete Cosine Transform
2014
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2014/926170 A novel iris biometric watermarking scheme is proposed focusing on iris recognition instead of the traditional watermark for increasing the security of the digital products. The preprocess of iris image is to be done firstly, which generates the iris biometric template from person's eye images. And then the templates are to be on discrete cosine transform; the value of the discrete cosine is encoded to BCH error control coding. The host image is divided into four areas equally correspondingly. The BCH codes are embedded in the sing…
Synthetic biomolecular condensates to engineer eukaryotic cells
2021
Abstract The compartmentalization of specific functions into specialized organelles is a key feature of eukaryotic life. In particular, dynamic biomolecular condensates that are not membrane enclosed offer exciting opportunities for synthetic biology. In recent years, multiple approaches to generate and control condensates have been reported. Notably, multiple orthogonally translating organelles were designed that enable precise protein engineering inside living cells. Despite being built from only very few components, orthogonal translation can be engineered with subresolution precision at different places inside the same cell to create mammalian cells with multiple expanded genetic codes.…
A New Universal Cellular Automaton Discovered by Evolutionary Algorithms
2004
In Twenty Problems in the Theory of Cellular Automata, Stephen Wolfram asks “how common computational universality and undecidability [are] in cellular automata.” This papers provides elements of answer, as it describes how another universal cellular automaton than the Game of Life (Life) was sought and found using evolutionary algorithms. This paper includes a demonstration that consists in showing that the presented R automaton can both implement any logic circuit (logic universality) and a simulation of Life (universality in the Turing sense).
On the Statistical Properties of Capacity Outage Intervals in OSTBC-MIMO Rayleigh Fading Channels
2016
This paper deals mainly with the study of the asymptotic probability density functions (PDFs) of the outage durations of the instantaneous capacity of orthogonal space-time block code (OSTBC) multiple-input multiple-output (MIMO) systems over Rayleigh channels. Drawing upon known statistical properties for the asymptotic behavior of chi-squared processes at low levels, we provide approximate solutions for the PDF, the cumulative distribution function (CDF), and the $k$ th-order moments of the outage intervals of the underlying capacity processes. Then, as an application of the derived PDF, the performance assessment of capacity simulators is reported. Following this, we introduce the newly …