Disjoint LDPC Coding for Gaussian Broadcast Channels

Low-density parity-check (LDPC) codes have been used for communication over a two-user Gaussian broadcast channel. It has been shown in the literature that the optimal decoding of such system requires joint decoding of both user messages at each user. Also, a joint code design procedure should be performed. We propose a method which uses a novel labeling strategy and is based on the idea behind the bit-interleaved coded modulation. This method does not require joint decoding and/or joint code optimization. Thus, it reduces the overall complexity of near-capacity coding in broadcast channels. For different rate pairs on the boundary of the capacity region, pairs of LDPC codes are designed to demonstrate the success of this technique.Comment: 5 pages, 1 figure, 3 tables, To appear in Proc. IEEE International Symposium on Information Theory (ISIT 2009), Seoul, Korea, June-July 200

A Model to Evaluate the Organizational Readiness for Big Data Adoption

Evaluating organizational readiness for adopting new technologies always was an important issue for managers. This issue for complicated subjects such as Big Data is undeniable. Managers tend to adopt Big Data, with the best readiness. But this is not possible unless they can assess their readiness. In the present paper, we propose a model to evaluate the organizational readiness for Big Data adoption. To accomplish this objective, firstly, we identified the criteria that impact organizational readiness based on a comprehensive literature review. In the next step using Principal Component Analysis (PCA) for criterion reduction and integration, twelve main criteria were identified. Then the hierarchical structure of criteria was developed. Further, Fuzzy Best- Worst Method (FBWM) has been used to identify the weight of the criteria. The finding enables decision-makers to appropriately choose the more important criteria and drop unimportant criteria in strengthening organizational readiness for Big Data adoption. Statistics-based hierarchical model and MCDM based criteria weighting have been proposed, which is a new effort in evaluating organizational readiness for Big Data adoption

A FBWM-PROMETHEE approach for industrial robot selection

Industrial engineering; Multidisciplinary design optimization; Manufacturing engineering; Technology management; Operations management; Industry management; Business management; Industrialization; Industrial robots; Fuzzy best-worst method; PROMETHEE; MCDM; Robot selection; Criteria.publishersversionpublishe

Multiple Exciton Generation in Si and Ge Nanocrystals: An ab Initio Comparative Study

We have simulated multiexciton generation (MEG) processes in Si and Ge nanocrystals, employing the equation of motion coupled cluster single and double as a high-level ab initio approach. Simulations, consistent with the experimental results reported so far, reveal the key role of the d-polarized valence component in the chosen basis set on the accuracy and reliability of the results. Moreover, the MEG thresholds calculated with def2SVP basis set are ∼8.23(8.07) eV for seven (eight)-atom Si clusters and ∼7.58(6.84) eV for similar Ge clusters. The normalized MEG thresholds of Ge nanocrystals are 8% smaller with respect to Si. Thus, in contrast to Si, they are more appealing to the optical device designers for enhancing the device quantum efficiency. Furthermore, the resemblance of the symmetry of the simulated seven-atom clusters to those of the experimentally domelike grown nanocrystals makes the behavior of their MEG quantum probability similar

Fusion analysis of functional MRI data for classification of individuals based on patterns of activation.

Classification of individuals based on patterns of brain activity observed in functional MRI contrasts may be helpful for diagnosis of neurological disorders. Prior work for classification based on these patterns have primarily focused on using a single contrast, which does not take advantage of complementary information that may be available in multiple contrasts. Where multiple contrasts are used, the objective has been only to identify the joint, distinct brain activity patterns that differ between groups of subjects; not to use the information to classify individuals. Here, we use joint Independent Component Analysis (jICA) within a Support Vector Machine (SVM) classification method, and take advantage of the relative contribution of activation patterns generated from multiple fMRI contrasts to improve classification accuracy. Young (age: 19-26) and older (age: 57-73) adults (16 each) were scanned while listening to noise alone and to speech degraded with noise, half of which contained meaningful context that could be used to enhance intelligibility. Functional contrasts based on these conditions (and a silent baseline condition) were used within jICA to generate spatially independent joint activation sources and their corresponding modulation profiles. Modulation profiles were used within a non-linear SVM framework to classify individuals as young or older. Results demonstrate that a combination of activation maps across the multiple contrasts yielded an area under ROC curve of 0.86, superior to classification resulting from individual contrasts. Moreover, class separability, measured by a divergence criterion, was substantially higher when using the combination of activation maps

Polyunsaturated fatty acid accumulation and antioxidant enzyme activity in red tilapia (Oreochromis hybrid) fed high omega-3 diets

This study was conducted to investigate the change of muscle fatty acid profiles with increasing age and to measure the activities of muscle antioxidant enzymes in red tilapia (Oreochromis hybrid) fed with relatively high n-3 diet. Fish were reared in aquaria and fed with a formulated diet which was high in n-3 polyunsaturated fatty acid (PUFA) for 75 days. Significant increase (p<0.05) of saturated fatty acids, monoenes and n-6 PUFA was observed at 60 days after start of the experiment, while significant increase of n-3 PUFA occurred at 75 days after start of the experiment. The superoxide dismutase and glutathione peroxidase activities were found to be 1.5 ± 0.1 and 0.4 ± 0.1 (U/g; Mean ± SE; n = 10), respectively. Lipid peroxidation value (MDA) was found to be 21.4 ± 0.5 nmol/g (Mean ± SE; n = 10). Our results suggested that feeding red tilapia with a high n-3 finishing diet from 75 days prior to harvesting can successfully increase the n-3 PUFA content of fillet. However, the relatively low antioxidant enzymes activity and high value of lipid peroxidation in the muscle tissue should be considered for proper storage and handling of red tilapia fillet to ensure the availability of desirable n-3 PUFA and to avoid the accumulation of undesirable oxidation products

Concomitant COVID-19 and acute ischemic stroke in patients transferred by emergency medical service during first wave of pandemic in Tehran, Iran; a cross-sectional study

Objective:&nbsp;We conducted this study to evaluate the prevalence of concomitant COVID-19 in acute ischemic stroke (AIS) patients admitted to stroke centers of Tehran, Iran.&nbsp;Methods: We conducted a retrospective cross-sectional study in a 45-day period. AIS patients transferred by emergency medical service (EMS) to all medical centers of the city were included. Information was recorded and compared in two groups: patients who tested positive for COVID-19 and those who were negative.&nbsp;Result: Emergency medical technicians (EMTs) screened 348 patients as AIS cases, of whom, AIS was ultimately confirmed in 311 (89.4%) patients; and 58 (18.6%) of the 311 AIS patients were diagnosed with concomitant COVID-19 infection. The National Institutes of Health Stroke Scale (NIHSS) scores of COVID-19 positive AIS patients were significantly higher than non-COVID-19 AIS patients (16.3±3.7 vs. 11.8±4.3; p&lt;0.001). There was also a significant difference in length of hospital stay between the two groups (11.1±1.8 vs. 8.8±4.3 days; p&lt;0.001). However, data showed no significant difference regarding prevalence of in-hospital mortality between the two groups (1.6% vs. 3.5%; p=0.320).&nbsp;Conclusion:&nbsp;Our study results showed that AIS patients with concomitant COVID-19 infection had higher NIHSS scores and longer length of hospital stay compared to patients without concomitant COVID-19 infection