The bootstrap and its application in signal processing

The bootstrap is an attractive tool for assessing the accuracy of estimators and testing hypothesis for parameters where conventional techniques are not valid, such as in small data-sample situations. We highlight the motivations for using the bootstrap in typical signal processing applications and give several practical examples. Bootstrap methods for testing statistical hypotheses are described and we provide an analysis of the accuracy of bootstrap tests. We also discuss how the bootstrap can be used to estimate a variance-stabilizing transformation to define a pivotal statistic, and we demonstrate the use of the bootstrap for constructing confidence intervals for flight parameters in a passive acoustic emission problem     

Diffusion of two associated solvents in various compositions through a swelling polymer material,EVAc

The particular sorption by a swelling polymer with the transfer of hydrocarbons was studied in order to evaluate some barrier properties of this material. The transfer of two types of solvents through two varieties of ethylene vinyl acetate was investigated: absorption of pure toluene and pure n‐hexane and absorption of a toluene/hexane mixture in various compositions. A comparison between the two processes showed that these transfers were very different and depended on two factors: vinyl acetate content and composition of the mixture. The kinetics of absorption were calculated for various compositions. The profiles of concentration as well as the kinetics of swelling were evaluated using a numerical model deduced from the general theory of radial diffusion of a substance with change in dimensions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2099–2106, 2007     

On tasks synchronization with the MMS protocol

The MMS protocol is a powerful tool for communication as well as for synchronization between manufacturing equipment such as robots, programmable logic controllers, etc. This paper shows how the MMS services can be used to handle tasks synchronization in a distributed environment. The MMS weaknesses regarding temporal aspects and possible directions to alleviate these weaknesses are also presented.     

Clinical and Molecular Characterization of Patients with Mucopolysaccharidosis Type I in an Algerian Series

Mucopolysaccharidoses (MPS’s) represent a subgroup of lysosomal storage diseases related to a deficiency of enzymes that catalyze glycosaminoglycans degradation. Mucopolysaccharidosis type I (MPS I) is a rare autosomal recessive disorder caused by a deficiency of α-l-iduronidase encoded by the IDUA gene. Partially degraded heparan sulfate and dermatan sulfate accumulate progressively and lead to multiorgan dysfunction and damage. The aim of this study is to describe the clinical, biochemical, and molecular characteristics of 13 Algerian patients from 11 distinct families. MPS I diagnosis was confirmed by molecular study of the patients’ IDUA gene. Clinical features at the diagnosis and during the follow-up are reported. Eighty-four percent of the studied patients presented with a mild clinical phenotype. Molecular study of the IDUA gene allowed the characterization of four pathological variations at the homozygous or compound heterozygote status: IDUA NM_00203.4:c.1598C>G-p.(Pro533Arg) in 21/26 alleles, IDUA NM_00203.4:c.532G>A-p.(Glu178Lys) in 2/26 alleles, IDUA NM_00203.4:c.501C>G-p.(Tyr167*) in 2/26 alleles, and IDUA NM_00203. 4: c.1743C>G-p.(Tyr581*) in 1/26 alleles. This molecular study unveils the predominance of p.(Pro533Arg) variation in our MPS I patients. In this series, the occurrence of some clinical features linked to the Scheie syndrome is consistent with the literature, such as systematic valvulopathies, corneal opacity, and umbilical hernia; however, storage signs, facial dysmorphic features, and hepatomegaly were more frequent in our series. Screening measures for these debilitating diseases in highly consanguineous at-risk populations must be considered a priority health problem.     

Natural occurrence of zearalenone in Tunisian wheat grains

Fusarium mycotoxins are worldwide occurring in cereals and they are frequently reported in fresh or stored grains. Cereals represent a staple food for the Tunisian population; it therefore has a high social, economic and nutritional relevance. Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by a variety of Fusarium fungi in temperate and warm countries. Fungi-producing ZEN contaminates corn, barley, wheat, sorghum and rice. A total of 205 samples of wheat were collected during the harvest year of 2010 from the major cropping areas in Tunisia and they were analyzed for zearalenone contamination. The aim of this study was to investigate for the first time the presence of ZEN in widely-consumed cereals in Tunisia, especially durum and tender wheat, to compare the levels of contamination by ZEN with the European norms and to suggest some factors that can promote the production of ZEN in Tunisia. To perform this study, we developed and validated in our laboratory conditions an HPLC method for quantitative analysis of ZEN in solid cereal samples. Our results showed that the incidence of ZEN contamination was 75%. The levels of contamination determined in the positive samples ranged between 3 and 560 μg/kg with a mean value of 60 μg/kg. These important amounts of ZEN in wheat can be attributed to the Tunisian climate, warm temperature and prolonged wetness witch are favor to Fusarium growth and mycotoxin production during the cultivation and the final ripening period of wheat grains.     

Optimal Sizing of a DBD Ozone Generator Using Response Surface Modeling

Dielectric barrier discharge (DBD) reactors used as ozone generators are well known today and widely used for water treatment and air disinfection. The purpose of this article is to propose an experimental procedure based on the response surface modeling in order to optimize the geometrical dimensions of the cylindrical shape ozone generator, i.e., the discharge gap and the electrodes length. Because an effective ozone generator is expected to give high ozone concentration with a minimum of power requirements, the applied high voltage was associated with the geometrical parameters to carry out a composite centered faces design. Obtained results indicate that for an efficient ozone generator, length of the electrodes needs to be optimized while the discharge gap should be minimized.     

On the performance of cyclic moments-based parameter estimators ofamplitude modulated polynomial phase signals

Parameter estimation of amplitude-modulated polynomial phase signals embedded in additive white Gaussian noise is considered. The amplitude modulation is modeled as the sum of a real-valued deterministic function and a zero mean correlated stationary random process. It is shown that cyclic moments-based estimators, previously proposed for parameter estimation of polynomial phase signals modulated by stationary random processes, can be adapted to the more general signal model considered here. The covariance matrices of the cyclic moments-based amplitude and phase parameter estimators are derived for large sample lengths. Using this result, it is shown how the lags can be chosen to minimize the large-sample variances of the cyclic moments-based phase parameter estimators. Comparisons with the Cramer-Rao bounds are performed under the assumption of a Gaussian modulating process. The theoretical derivations are confirmed by simulation results