21 research outputs found
An efficient CDMA decoder for correlated information sources
We consider the detection of correlated information sources in the ubiquitous
Code-Division Multiple-Access (CDMA) scheme. We propose a message-passing based
scheme for detecting correlated sources directly, with no need for source
coding. The detection is done simultaneously over a block of transmitted binary
symbols (word). Simulation results are provided demonstrating a substantial
improvement in bit-error-rate in comparison with the unmodified detector and
the alternative of source compression. The robustness of the error-performance
improvement is shown under practical model settings, including wrong estimation
of the generating Markov transition matrix and finite-length spreading codes.Comment: 11 page
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Sleep quality is associated with vitamin B12 status in female Arab students
Studies have explored how vitamin B12 status affects sleep among elders and children, but this remains to be investigated among young adults. We used the Pittsburgh Sleep Quality Index (PSQI) to assess the association between serum vitamin B12 and sleep among female college students in Saudi Arabia. In this cross-sectional study, we enrolled 355 participants (age (years), 20.7 ± 1.5; body mass index, 23.6 kg/m2 ± 5.2) at King Saud University, Riyadh, Saudi Arabia. Fasting blood samples were analyzed regarding the serum vitamin B12 and blood lipids. Anthropometric, socio-demographic, clinical history, stress, physical activity, and dietary data were collected. We assessed the sleep statuses of the participants using the PSQI. Around 72% of the participants were âpoorâ sleepers (PSQI > 5). Subgroup analysis within the tertiles showed that participants with higher vitamin B12 in the second and third tertiles reported better scores for sleep quality (B ± SE = â12.7 ± 5.6, p = 0.03; B ± SE = â32.7 ± 16.4, p = 0.05, respectively) and also reported a lower use of sleep medication (B ± SE = â21.2 ± 9.9, p = 0.03, in the second tertile only), after adjusting for the waistâhip ratio and stress. However, sleep was not found to be directly associated with either serum vitamin B12 or dietary vitamin B12. In conclusion, the serum vitamin B12 results show that the participants with higher vitamin B12 in the second and third tertiles reported better scores on the sleep quality scale and a lower use of sleep medication. However, no such associations were observed with the overall PSQI. More studies with larger sample sizes are needed to establish a direct relationship between sleep and vitamin B12
Genotype and Growing Environment Interaction Shows a Positive Correlation between Substrates of Raffinose Family Oligosaccharides (RFO) Biosynthesis and Their Accumulation in Chickpea (Cicer arietinum L.) Seeds
To develop genetic improvement strategies to modulate raffinose family oligosaccharides (RFO) concentration in
chickpea (Cicer arietinum L.) seeds, RFO and their precursor concentrations were analyzed in 171 chickpea genotypes from
diverse geographical origins. The genotypes were grown in replicated trials over two years in the field (Patancheru, India) and in
the greenhouse (Saskatoon, Canada). Analysis of variance revealed a significant impact of genotype, environment, and their
interaction on RFO concentration in chickpea seeds. Total RFO concentration ranged from 1.58 to 5.31 mmol/100 g and from
2.11 to 5.83 mmol/100 g in desi and kabuli genotypes, respectively. Sucrose (0.60â3.59 g/100 g) and stachyose (0.18â2.38 g/
100 g) were distinguished as the major soluble sugar and RFO, respectively. Correlation analysis revealed a significant positive
correlation between substrate and product concentration in RFO biosynthesis. In chickpea seeds, raffinose, stachyose, and
verbascose showed a moderate broad sense heritability (0.25â0.56), suggesting the use of a multilocation trials based approach in
chickpea seed quality improvement programs
A Lower Bound on the Probability of a Finite Union of Events
A new lower bound on the probability P (A 1 [ \Delta \Delta \Delta [ AN ) is established in terms of only the individual event probabilities P (A i )'s and the pairwise event probabilities P (A i " A j )'s. This bound is shown to be always at least as good as two similar lower bounds: one by de Caen (1997) and the other by Dawson and Sankoff (1967). Numerical examples for the computation of this inequality are also provided. Keywords: Probability of a union, lower bound, linear programming. 1 Main results Consider a finite family of events A 1 ; A 2 ; : : : ; AN in a finite 1 probability space (\Omega ; P ), where N is a fixed positive integer. For each x 2 \Omega\Gamma let p(x) 4 =P (fxg), and let the degree of x -- denoted by deg(x) -- be the number of A i 's that contain x. Define B i (k) 4 =fx 2 A i : deg(x) = kg and a i (k) 4 =P (B i (k)); where i = 1; 2; : : : ; N and k = 1; 2; : : : ; N . We obtain the following lemma. This work was supported in part by NSERC and..