Turbo-Detected Unequal Protection MPEG-4 Audio Transceiver Using Convolutional Codes, Trellis Coded Modulation and Space-Time Trellis Coding

A jointly optimised turbo transceiver capable of providing unequal error protection is proposed for employment in an MPEG-4 aided audio transceiver. The transceiver advocated consists of Space-Time Trellis Coding (STTC), Trellis Coded Modulation (TCM) and two different-rate Non-Systematic Convolutional codes (NSCs) used for unequal error protection. A benchmarker scheme combining STTC and a single-class protection NSC is used for comparison with the proposed scheme. The audio performance of the both schemes is evaluated when communicating over uncorrelated Rayleigh fading channels. It was found that the proposed unequal protection turbo-transceiver scheme requires about two dBs lower transmit power than the single-class turbo benchmarker scheme in the context of the MPEG-4 audio transceiver, when aiming for an effective throughput of 2 bits/symbol, while exhibiting a similar decoding complexity

Turbo-detected unequal protection audio and speech transceivers using serially concatenated convolutional codes, trellis coded modulation and space-time trellis coding

The MPEG-4 TwinVQ audio codec and the AMR-WB speech codec are investigated in the context of a jointly optimised turbo transceiver capable of providing unequal error protection. The transceiver advocated consists of serially concatenated Space-Time Trellis Coding (STTC), Trellis Coded Modulation (TCM) and two different-rate Non-Systematic Convolutional codes (NSCs) used for unequal error protection. A benchmarker scheme combining STTC and a single-class protection NSC is used for comparison with the proposed scheme. The audio and speech performance of both schemes is evaluated, when communicating over uncorrelated Rayleigh fading channels. An $E_b/N_0$ value of about 2.5 (3.5)~dB is required for near-unimpaired audio (speech) transmission, which is about 3.07 (4.2)~dB from the capacity of the system

Turbo-Detected Unequal Error Protection Irregular Convolutional Codes Designed for the Wideband Advanced Multirate Speech Codec

Abstract—since the different bits of multimedia information, such as speech and video, have different error sensitivity, efficient unequalprotection channel coding schemes have to be used to ensure that the perceptually more important bits benefit from more powerful protection. Furthermore, in the context of turbo detection the channel codes should also match the characteristics of the channel for the sake of attaining a good convergence performance. In this paper, we address this design dilemma by using irregular convolutional codes (IRCCs) which constitute a family of different-rate subcodes. we benefit from the high design flexibility of IRCCs and hence excellent convergence properties are maintained while having unequal error protection capabilities matched to the requirements of the source. An EXIT chart based design procedure is proposed and used in the context of protecting the different-sensitivity speech bits of the wideband AMR speech codec. As a benefit, the unequalprotection system using IRCCs exhibits an SNR advantage of about 0.4dB over the equal-protection system employing regular convolutional codes, when communicating over a Gaussian channel

Surveillance of Influenza B Virus Strains Circulating in Malaysia (2002—2006)

Background: The Virology Unit, Institute for Medical Research (IMR), Kuala Lumpur has been designated as the National Influenza Centre since 1968, carrying out influenza surveillance activities for the Ministry of Health Malaysia. These activities are important for preparation of epidemics and pandemics. In the past decade, several outbreaks of influenza B have been reported in this country. Thus, the aims of this study are to evaluate the incidence and to identify the circulating viral strain of influenza type B in Malaysia. Methods: All respiratory specimens received from several sentinel sites from patients presenting with influenza-like illness (ILI) were included in this study. The virus was detected by culture method using Madin Darby Canine Kidney (MDCK) cells with combination of Immunofluorescence (IF) and haemagglutination inhibition (HAI) techniques. Results: From 2002 to 2006 the National Influenza Centre, IMR received a total of 5,463 specimens from patients presenting with ILI. Of these, 220 (4.0%) were found to be positive for Influenza B virus and further analysis showed that there were four major strains circulating in Malaysia during the five years study period. The predominant strain in 2002 was B/Hong Kong/330/2001-like virus, B/Sichuan/379/99-like virus in 2003, B/Shanghai/361/2002- like virus in 2004, B/Hong Kong/330/2001-like virus in 2005 and B/Malaysia/2506/2004-like virus in 2006. Conclusion: The surveillance activities are not only important as an early warning for outbreak preparedness but also important in detecting new strains that can be used in the annual vaccine formulation

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3�6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55 of the global rise in mean BMI from 1985 to 2017�and more than 80 in some low- and middle-income regions�was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing�and in some countries reversal�of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories. © 2019, The Author(s)

Ionic conductivity of PEMA-LiClO4 polymer electrolytes

Solid polymer electrolytes comprised of various weight percent ratios of poly(ethyl methacrylate) (PEMA) and lithium perchlorate (LiClO4) salt were prepared via solution casting technique using N,N-dimethylformamide (DMF) as the solvent. The conductivity values of the electrolytes were determined via impedance spectroscopy. The conductivity of the PEMA-LiClO4 electrolytes increased with increasing salt concentration and the highest conductivity obtained was in the order of 10-6 S cm-1 at salt concentration of 20 wt%. The conductivity decreased for higher salt concentration. In order to understand the conductivity behavior, XRD and dielectric studies were done. The results showed that the conductivity was influenced by the fraction of amorphous region and number of charge carriers in the system. The transference number measurement was also performed on the highest conducting electrolyte systems. The result of the measurement indicated that the systems were ionic conductors

A Proportional-Derivative Endogenous Insulin Secretion model with an Adapted Gauss Newton Approach

Endogenous insulin (UN) secreted by pancreatic β-cells plays a leading role in glucose homeostasis. Pathological changes in UN can enable early diagnosis of metabolic dysfunction before the emergence of type 2 diabetes. The dynamic insulin sensitivity and secretion test (DISST) is a dynamic test that is able to quantify participant-specific insulin sensitivity (SI) values and UN profiles. Like most studies, the DISST uses direct inversion of C-peptide concentration measurements to quantify a UN profile which relies on the assumption that insulin and C-peptide are equimolarly secreted from β-cells. This study develops a proportional-derivative (PD) control model that defines UN as a function of glucose concentration to provide further insight and modeling capability for this prediabetic state. Results show that individuals with normal glucose tolerance (NGT) tend to have higher gain ratio compared to individuals with impaired fasting glucose (IFG) with median values of 19.11 and 2.79 min, respectively. In particular, the main difference between the UN profiles of NGT and IFG group lies within the derivative gain (), specifically in first phase secretion (U1). A higher value of is needed in response to an abrupt increase in plasma glucose level. This proposed model offers model simplicity as well as a link between insulin secretion and glucose concentration that is able to provide more information in determining each participant’s glycemic condition