12 research outputs found

    Enhancing BER performance limit of BCH and RS codes using multipath diversity

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    Modern wireless communication systems suffer from phase shifting and, more importantly, from interference caused by multipath propagation. Multipath propagation results in an antenna receiving two or more copies of the signal sequence sent from the same source but that has been delivered via different paths. Multipath components are treated as redundant copies of the original data sequence and are used to improve the performance of forward error correction (FEC) codes without extra redundancy, in order to improve data transmission reliability and increase the bit rate over the wireless communication channel. For a proof of concept Bose, Ray-Chaudhuri, and Hocquenghem (BCH) and Reed-Solomon (RS) codes have been used as FEC to compare their bit error rate (BER) performances. The results showed that the wireless multipath components significantly improve the performance of FEC. Furthermore, FEC codes with low error correction capability and employing the multipath phenomenon are enhanced to perform better than FEC codes which have a bit higher error correction capability and did not utilise the multipath. Consequently, the bit rate is increased, and communication reliability is improved without extra redundancy

    Utilisation of multipath phenomenon to improve the performance of BCH and RS codes

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    In wireless communication, there exists a phenomenon known as ‘multipath’. This phenomenon is considered as a disadvantage because it causes interference. The multipath phenomenon results in an antenna receiving two or more signals from the same sent signal from different paths. This paper considers them as redundant copies of the transmitted data and utilises them to improve the performance of forward error correction (FEC) codes without extra redundancy, in order to improve data transmission reliability and increase the bit rate over wireless communication channels. The system was evaluated in bit error rate (BER) and used Bose, Ray-Chaudhuri and Hocquenghem (BCH) and Reed-Solomon (RS) codes as FEC. The results showed that the utilisation of the multipath improves the performance of FEC. Furthermore, the performance of FEC codes had t1 error correction capability and employed the multipath is better than FEC codes have t2 error correction capability and without the multipath, where t1 < t2. Consequently, the bit rate is increased, and communication reliability is improved without extra redundancy

    Network coding/forward error correction code for multiple-input multiple-output wireless communication system

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    A reliable wireless communication channel is amongst the most important issues in a wireless network. Due to its nature, a reliable wireless communication channel is a challenge to provide. Wireless channel diversity is an efficient technique to achieve reliable transmission. Multi-antenna exploits spatial diversity as a method that has been proved to drastically increase channel capacity while keeping bit error rates (BER) near Shannon (lower bound) limits. Forward error correction code (FEC) or channel coding is an error control technique that is used to provide a time diversity to immunize data against errors over the noisy and unreliable wireless channel (Duman & Ghrayeb, 2007). The main idea behind FEC is that the transmitter encodes data by using error correction code (ECC) to add redundancy. This redundancy allows the receiver to detect and correct a specific number of bits in error - at a time - that may occur in the data stream. Multiple-input multiple-output (MIMO) systems combined with channel coding are shown to improve system BER and channel capacity performance in wireless communications. The combination is often referred to as a coded MIMO system. The aim of this research is to design or improve a FEC code algorithm for wireless communication network. This algorithm should be suitable to combine with MIMO system and be able to detect and correct the corrupted data in order to decrease the BER and increase wireless channel efficiency. The computational complexity and the data overhead will be used to measure the performance efficiency of the proposed algorithm

    The Saudi Thoracic Society guidelines for influenza vaccinations

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    Influenza viruses are responsible for the influenza outbreaks that lead to significant burden and cause significant morbidity and mortality worldwide. Based on the core proteins, influenza viruses are classified into three types, A, B, and C, of which only A and B cause significant human disease and so the vaccine is directed against these two subtypes only. The effectiveness of the vaccine depends on boosting the immune system against the serotypes included within it. As influenza viruses undergo periodic changes in their antigen, the vaccine is modified annually to ensure susceptibility. In contrast to other countries, Saudi Arabia faces a unique and challenging situation due to Hajj and Umrah seasons, when millions of people gather at the holy places in Mecca and Madinah, during which influenza outbreaks are commonly found. Such challenges making the adoption of strict vaccination strategy in Saudi Arabia is of great importance. All efforts were made to develop this guideline in an easy-to-read form, making it very handy and easy to use by health care workers. The guideline was designed to provide recommendations for problems frequently encountered in real life, with special consideration for special situations such as Hajj and Umrah seasons and pregnancy

    Estimating the Severity and Subclinical Burden of Middle East Respiratory Syndrome Coronavirus Infection in the Kingdom of Saudi Arabia

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    Not all persons infected with Middle East respiratory syndrome coronavirus (MERS-CoV) develop severe symptoms, which likely leads to an underestimation of the number of people infected and an overestimation of the severity. To estimate the number of MERS-CoV infections that have occurred in the Kingdom of Saudi Arabia, we applied a statistical model to a line list describing 721 MERS-CoV infections detected between June 7, 2012, and July 25, 2014. We estimated that 1,528 (95% confidence interval (CI): 1,327, 1,883) MERS-CoV infections occurred in this interval, which is 2.1 (95% CI: 1.8, 2.6) times the number reported. The probability of developing symptoms ranged from 11% (95% CI: 4, 25) in persons under 10 years of age to 88% (95% CI: 72, 97) in those 70 years of age or older. An estimated 22% (95% CI: 18, 25) of those infected with MERS-CoV died. MERS-CoV is deadly, but this work shows that its clinical severity differs markedly between groups and that many cases likely go undiagnosed

    Estimating the Severity and Subclinical Burden of Middle East Respiratory Syndrome Coronavirus Infection in the Kingdom of Saudi Arabia

    No full text
    Not all persons infected with Middle East respiratory syndrome coronavirus (MERS-CoV) develop severe symptoms, which likely leads to an underestimation of the number of people infected and an overestimation of the severity. To estimate the number of MERS-CoV infections that have occurred in the Kingdom of Saudi Arabia, we applied a statistical model to a line list describing 721 MERS-CoV infections detected between June 7, 2012, and July 25, 2014. We estimated that 1,528 (95% confidence interval (CI): 1,327, 1,883) MERS-CoV infections occurred in this interval, which is 2.1 (95% CI: 1.8, 2.6) times the number reported. The probability of developing symptoms ranged from 11% (95% CI: 4, 25) in persons under 10 years of age to 88% (95% CI: 72, 97) in those 70 years of age or older. An estimated 22% (95% CI: 18, 25) of those infected with MERS-CoV died. MERS-CoV is deadly, but this work shows that its clinical severity differs markedly between groups and that many cases likely go undiagnosed

    Therapeutics discovery: From bench to first in-human trials

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    The ‘Therapeutics discovery: From bench to first in-human trials’ conference, held at the King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs (MNGHA), Kingdom of Saudi Arabia (KSA) from October 10-12, 2017, provided a unique opportunity for experts worldwide to discuss advances in drug discovery and development, focusing on phase I clinical trials. It was the first event of its kind to be hosted at the new research center, which was constructed to boost drug discovery and development in the KSA in collaboration with institutions, such as the Academic Drug Discovery Consortium in the United States of America (USA), Structural Genomics Consortium of the University of Oxford in the United Kingdom (UK), and Institute of Materia Medica of the Chinese Academy of Medical Sciences in China. The program was divided into two parts. A pre‑symposium day took place on October 10, during which courses were conducted on clinical trials, preclinical drug discovery, molecular biology and nanofiber research. The attendees had the opportunity for one-to-one meetings with international experts to exchange information and foster collaborations. In the second part of the conference, which took place on October 11 and 12, the clinical trials pipeline, design and recruitment of volunteers, and economic impact of clinical trials were discussed. The Saudi Food and Drug Administration presented the regulations governing clinical trials in the KSA. The process of preclinical drug discovery from small molecules, cellular and immunologic therapies, and approaches to identifying new targets were also presented. The recommendation of the conference was that researchers in the KSA must invest more fund, talents and infrastructure to lead the region in phase I clinical trials and preclinical drug discovery. Diseases affecting the local population, such as Middle East Respiratory Syndrome and resistant bacterial infections, represent the optimal starting point
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