Search results for "coding"
showing 10 items of 920 documents
A 16QAM super-orthogonal space-frequency code for broadband mobile communication systems with two transmit antennas
2010
We combine our previously designed 32-state super-orthogonal space-time trellis code (SOSTTC) with orthogonal frequency division multiplexing (OFDM) to build a broadband mobile communication system having a spectral efficiency that amounts to 4 bits/s/Hz depending on the length of the cyclic prefix used to avoid interframe interference. The transmitter is equipped with two antennas, where the OFDM frames they transmit are not independent, as they carry the same information in an orthogonal form. The 2N OFDM tones are grouped in N pairs of tones. Each group of two tones transmits the entries of a 2×2 orthogonal matrix. In our case, the entries are symbols taken from the rectangular 16-point …
A Wideband One-Ring MIMO Channel Model Under Non-Isotropic Scattering Conditions
2008
In this paper, we present a wideband one-ring multiple-input multiple-output (MIMO) channel model for non-isotropic scattering environments. The model is designed in such a way that the delay power spectral density (PSD) of the resulting reference channel model is identical to a given delay PSD. Furthermore, we present an efficient deterministic channel simulation model obtained by using the principle of deterministic channel modeling. The statistical properties of both the reference model and the simulation model are also studied. Analytical expressions will be presented for the temporal autocorrelation function (ACF), the two-dimensional (2D) space cross-correlation function (CCF), and th…
On the role of the upper part of words in lexical access: evidence with masked priming.
2012
More than 100 years ago, Huey (1908) indicated that the upper part of words was more relevant for perception than the lower part. Here we examined whether mutilated words, in their upper/lower portions (e.g., , , , ), can automatically access their word units in the mental lexicon. To that end, we conducted four masked repetition priming experiments with the lexical decision task. Results showed that mutilated primes produced a sizeable masked repetition priming effect. Furthermore, the magnitude of the masked repetition priming effect was greater when the upper part of the primes was preserved than when the lower portion was preserved –this was the case not only when the mutilated words we…
Detection of multiple species of humanParagonimusfrom Mexico using morphological data and molecular barcodes
2013
Paragonimus mexicanus is the causal agent of human paragonimiasis in several countries of the Americas. It is considered to be the only species of the genus present in Mexico, where it is responsible for human infection. Through the investigation of P. mexicanus specimens from several places throughout Mexico, we provide morphological, molecular and geographical evidence that strongly suggests the presence of at least three species from this genus in Mexico. These results raise questions regarding the diagnosis, treatment, prophylaxis and control of human paragonimiasis in Mexico. We also provide a brief discussion regarding biodiversity inventories and the convenience of providing molecula…
The ‘giant phyllosoma’ are larval stages of Parribacus antarcticus (Decapoda : Scyllaridae)
2014
Early reports on larval distributions are frustratingly obscure due to ambiguous identification of plankton samples. A particularly striking case is posed by the so-called ‘giant phyllosoma’ which attain 80 mm in total length and are among the largest larvae known in marine invertebrates. Based on the supposition that these giant larvae are produced by local species, Philip Robertson (1968) assigned them to Parribacus. In the present study, 12 phyllosoma larvae collected in the Coral Sea and corresponding to intermediate stages VI to IX are described in detail. The identity of these freshly caught specimens was confirmed as belonging to Parribacus antarcticus (Lund, 1793) by using DNA barco…
Socio-economic determinants of inter-regional mobility in patients with cancer
2017
This paper presents an investigation of inter-regional mobility in patients with cancer. Thanks to the availability of geocoded information on patients’ place of residence, the effect of socio-economic status and of other individual characteristics on inter-regional mobility is analysed through multi-level logit models. The extent of patient’s mobility, and its dependence on socio-economic status raises equity issues, as well as regional policy considerations.
Individual and contextual determinants of inter-regional mobility in cancer patients
2019
This paper will present an investigation of inter-regional mobility in patients with a diagnosis of cancer. By virtue of the availability of geocoded information relating to a patient's place of residence, the effect of socio-economic status and other individual characteristics regarding inter-regional mobility will be analysed by means of multilevel logit models. The results demonstrate the influence of age and comorbidity on mobility propensity, in addition to the treatment type, which plays a role in patient mobility. As contextual determinants, patients residing in less deprived areas show greater mobility than those who reside in materially deprived areas. The extent of patient mobilit…
The effect of neighborhood frequency in reading: Evidence with transposed-letter neighbors
2007
Transposed-letter effects (e.g., jugde activates judge) pose serious models for models of visual-word recognition that use position-specific coding schemes. However, even though the evidence of transposed-letter effects with nonword stimuli is strong, the evidence for word stimuli is scarce and inconclusive. The present experiment examined the effect of neighborhood frequency during normal silent reading using transposed-letter neighbors (e.g., silver, sliver). Two sets of low-frequency words were created (equated in the number of substitution neighbors, word frequency, and number of letters), which were embedded in sentences. In one set, the target word had a higher frequency transposed-le…
Decoding Emotional Valence from Electroencephalographic Rhythmic Activity
2017
We attempt to decode emotional valence from electroencephalographic rhythmic activity in a naturalistic setting. We employ a data-driven method developed in a previous study, Spectral Linear Discriminant Analysis, to discover the relationships between the classification task and independent neuronal sources, optimally utilizing multiple frequency bands. A detailed investigation of the classifier provides insight into the neuronal sources related with emotional valence, and the individual differences of the subjects in processing emotions. Our findings show: (1) sources whose locations are similar across subjects are consistently involved in emotional responses, with the involvement of parie…
Transmission of Genetic Properties in Permutation Problems: Study of Lehmer Code and Inversion Table Encoding
2021
Solution encoding describes the way decision variables are represented. In the case of permutation problems, the classical encoding should ensure that there are no duplicates. During crossover operations, repairs may be carried out to correct or avoid repetitions. The use of indirect encoding aims to define bijections between the classical permutation and a different representation of the decision variables. These encodings are not sensitive to duplicates. However, they lead to a loss of genetic properties during crossbreeding. This paper proposes a study of the impact of this loss both in the space of decision variables and in that of fitness values. We consider two indirect encoding: the …