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1.
Emad Mossa 《International Journal of Speech Technology》2017,20(1):163-169
This paper introduces a secure speech communication approach, which is based on encryption and authentication. This system is based on Advanced Encryption Standard (AES) for encryption and private image database for enhancement of encryption and for authentication. The idea of this cryptosystem is based on XOR of one image from image database with the clear speech before encryption and embedding the index number of this image in the database as a least significant bit watermark into speech. A comparison study is held between the AES block cipher algorithm and the proposed algorithm. This proposed cryptosystem used to enhance the security of AES algorithm and increase its immunity to brute force attacks. It used also to provide authentication and enhance security by addition of extra key which don’t need to be exchanged between parts depending on the embedded image. The extra proposed step remove residual intelligibility from clear speech and fill the silent periods within speech conversation and help in destroy format and pitch information. Security analyses are presented for the proposed cryptosystem from a strict cryptographic viewpoint. Experimental results verify and prove that the proposed cryptosystem is highly secure from the cryptographic viewpoint. 相似文献
2.
Zahir Nikraftar Esmaeel Parizi Seiyed Mossa Hosseini Behzad Ataie-Ashtiani 《Journal of Great Lakes research》2021,47(4):955-969
Lake Urmia is the second-largest hypersaline lake in the world. There has been a drastic water level drop of 7.2 m from 1995 to 2016. Beginning in October 2013, the Lake Urmia Restoration Plan (LURP) launched a 10-year program. An increase in water level and a relative improvement in Lake Urmia condition has been observed since 2017. It is an undecided and controversial issue whether the recent positive trend of Lake Urmia has been due to the LURP activities or it is a natural contribution of climate factors variations. To shed some light on this issue, we examine three other lakes, adjacent to the Lake Urmia basin, with similar rainfall variability to investigate their status during the same period. Van (Turkey), Mosul, and Tharthar (both in Iraq), are evaluated as well as Lake Urmia. Three decades of remotely sensed data including precipitation (), water level (), and lake extent () were considered for the mentioned lakes. A significant correlation was observed between standardized , and over the long-term period, especially for the recent three years (2 = 0.63–0.87). We show that the cumulative precipitation in the antecedent months played a major role in the improvement of these lakes' situation but with different time lags (up to 6 months for Van and Mosul lakes and up to 36 months for Lake Urmia and Tharthar lake). These findings could inform the planners of LURP to adopt strategies for achieving a sustainable state of Lake Urmia based on a more realistic outlook. 相似文献
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4.
M.E. Fadda M.B. Pisano L. Scaccabarozzi V. Mossa M. Deplano P. Moroni M. Liciardi S. Cosentino 《Journal of dairy science》2013
This study reports a rapid PCR-based technique using a one-enzyme RFLP for discrimination of yeasts isolated from bovine clinical and subclinical mastitis milk samples. We analyzed a total of 1,486 milk samples collected over 1 yr in south Sardinia and northern Italy, and 142 yeast strains were preliminarily grouped based on their cultural morphology and physiological characteristics. Assimilation tests were conducted using the identification kit API ID 32C and APILAB Plus software (bioMérieux, Marcy l’Etoile, France). For PCR-RFLP analysis, the 18S-ITS1-5.8S ribosomal(r)DNA region was amplified and then digested with HaeIII, and dendrogram analysis of RFLP fragments was carried out. Furthermore, within each of the groups identified by the API or PCR-RFLP methods, the identification of isolates was confirmed by sequencing of the D1/D2 region using an ABI Prism 310 automatic sequencer (Applied Biosystems, Foster City, CA). The combined phenotypic and molecular approach enabled the identification of 17 yeast species belonging to the genera Candida (47.9%), Cryptococcus (21.1%), Trichosporon (19.7%), Geotrichum (7.1%), and Rhodotorula (4.2%). All Candida species were correctly identified by the API test and their identification confirmed by sequencing. All strains identified with the API system as Geotrichum candidum, Cryptococcus uniguttulatus, and Rhodotorula glutinis also produced characteristic restriction patterns and were confirmed as Galactomyces geotrichum (a teleomorph of G. candidum), Filobasidium uniguttulatum (teleomorph of Crypt. uniguttulatus), and R. glutinis, respectively, by D1/D2 rDNA sequencing. With regard to the genus Trichosporon, preliminary identification by API was problematic, whereas the RFLP technique used in this study gave characteristic restriction profiles for each species. Moreover, sequencing of the D1/D2 region allowed not only successful identification of Trichosporon gracile where API could not, but also correct identification of misidentified isolates. In conclusion, the 18S-ITS1-5.8S region appears to be useful in detecting genetic variability among yeast species, which is valuable for taxonomic purposes and for species identification. We have established an RFLP database for yeast species identified in milk samples using the software GelCompar II and the RFLP database constitutes an initial method for veterinary yeast identification. 相似文献
5.
This paper shows the results of the smooth particle hydrodynamics(SPH) modelling of the hydraulic jump at an abrupt drop,where the transition from supercritical to subcritical flow is characterised by several flow patterns depending upon the inflow and tailwater conditions. SPH simulations are obtained by a pseudo-compressible XSPH scheme with pressure smoothing; turbulent stresses are represented either by an algebraic mixing-length model, or by a two-equation k-ε model. The numerical model is applied to analyse the occurrence of oscillatory flow conditions between two different jump types characterised by quasi-periodic oscillation,and the results are compared with experiments performed at the hydraulics laboratory of Bari Technical University. The purpose of this paper is to obtain a deeper understanding of the physical features of a flow which is in general difficult to be reproduced numerically,owing to its unstable character: in particular, vorticity and turbulent kinetic energy fields, velocity, water depth and pressure spectra downstream of the jump, and velocity and pressure cross-correlations can be computed and analysed. 相似文献
6.
Michele Mossa 《Canadian Metallurgical Quarterly》2004,130(7):704-717
This paper presents experimental results of a turbulent neutrally buoyant jet vertically discharged in a stagnant ambient and of the same jet discharged in a flow field of regular waves, in the intermediate range between deep and shallow water. A number of such studies have been performed on this configuration in the past, but mostly limited to concentration (dilution) measurements. Thus one could argue the need for a detailed analysis of this problem with modern instrumentation. This paper will address the deficiency and will present the results of a new experimental study into wave-induced mixing. Velocity jet components were measured with a backscatter, two-component four-beam laser Doppler anemometer system. For the cases of jets with waves, ensemble-averaged velocities were obtained by phase averaging the measured signals separated by the wave period over about 500 waves. The main results of the present study indicate the following: (1) the entrained flow is higher in the case of jet with waves; (2) oscillating velocity components cannot be described by classic wave motion theories; (3) comparison of the root-mean square of turbulent velocity components indicates the effect of wave presence; (4) in the case of jet-wave interaction, the reduction of the jet momentum shown in literature can be explained by the presence of the turbulent Reynolds normal stresses (which are not as small as in the case of stagnant ambient and, consequently, cannot be ignored) and the wave Reynolds normal stresses; and (5) the analysis of the wave Reynolds shear stresses shows that it is not always right to apply a wave motion theory to obtain the statistical contribution of the wave field; a conclusion particularly interesting in order to enable the improvement of mathematical models present in literature. 相似文献
7.
Lampante olive oil refining with supercritical carbon dioxide 总被引:6,自引:4,他引:6
P. Bondioli C. Mariani A. Lanzani E. Fedeli A. Mossa A. Muller 《Journal of the American Oil Chemists' Society》1992,69(5):477-480
Lampante olive oil has been treated in a supercritical CO2 extraction plant operating in a continuous countercurrent mode. We report the results of a systematic investigation to define
the optimal operative parameters. We also have examined the compositional variation of lampante olive oil samples with different
characteristics and of different geographic origins before and after refining at optimal conditions. Although practical feasibility
of the proposed procedure can be questioned, the results demonstrate the possibility of fractionating components contained
in the starting oil even if present at trace levels. 相似文献
8.
D.?Abdul?Qader Raid?A.?IsmailEmail author Ahmed?A.?Mossa Khaleel?I.?Hassoon 《Journal of Materials Science: Materials in Electronics》2011,22(11):1681-1684
Nanostructured tin dioxide (SnO2) film was deposited on glass substrate by thermal evaporation of tin metal followed by thermal oxidation at 600 °C for 2 h.
XRD investigation confirms that grown film is crystalline tetragonal rutile. The average optical transmittance of the film
was as high as 90%. The optical band gap of the nanostructured SnO2 was estimated from transmittance data and found to be 3.4 eV. The variation of electrical conductivity with temperature was
investigated. The root mean square (RMS) roughness and topography of the film were investigated by atomic force microscopy
and found to be 2 nm with grain size of 17 nm. 相似文献
9.
Berry DP Lonergan P Butler ST Cromie AR Fair T Mossa F Evans AC 《Journal of dairy science》2008,91(1):329-337
There is a paucity of studies on the effect of intrauterine conditions on subsequent progeny performance in dairy cows. Using a large national data set on Irish Holstein-Friesian dairy cows, the objective of this study was to determine if intrauterine conditions, quantified by a maternal genetic variance component, significantly affected milk production, age at first calving, calving interval, somatic cell score (natural logarithm of somatic cell count) and survival in first-, second-, and third-parity female offspring. Maternal genetic variance for each trait in each parity was estimated in a linear mixed model which included, other than fixed effects, direct additive genetic, maternal genetic, cytoplasmic and permanent environmental effect of the dam, and residual component. A covariance was also estimated between the direct additive and maternal genetic components where possible. Because calves in Irish dairy herds are separated from dams at birth, a significant maternal genetic variance (with all other random effects in the model) indicates a prepartum maternal effect. A significant maternal genetic variance was estimated for 305-d milk yield in first and third lactation, somatic cell score in first lactation, and survival to second lactation from 188,144 lactations on 80,881 animals. Where estimated, a negative correlation existed between the direct additive and maternal genetic components. Regression of maternal mixed model solutions on dam milk production at different stages relative to conception revealed that greater milk yield preconception and during gestation was associated with reduced survival and milk yield and greater somatic cell count in the progeny. This study suggests that offspring survival and performance are affected by prepartum conditions that offspring experience as an oocyte, embryo, or fetus, one of which is mediated through milk production (or factors related to milk production) of the dam. 相似文献
10.
Studies summarizing stream restoration projects in the US are outdated and omit the majority of restoration projects in Florida. To address this gap, we compiled stream restoration data from diverse sources to create a Florida Stream Restoration Database (FSRD, available at http://www.watershedecology.org/databases.html ) containing information on project type, location, completion date, and costs. The FSRD contains 178 projects categorized by restoration type, including riparian management (23%), stream reclamation (19%), flow modification (13%), bank stabilization (12%), channel reconfiguration (11%), in‐stream habitat improvements (11%), floodplain reconnection (6%), invasive species removal (4%), and dam removal (1%). Projects were spatially clustered into three geographic regions, providing insight on the diversity of initiatives, needs, and funding sources of land management agencies and private landowners that motivated restoration efforts. Projects in the Florida panhandle emphasized in‐stream habitat restoration, while peninsular projects were dominated by flow modification, and projects in the west central region focused on stream reclamation to mitigate surface mining practices and water quality and habitat improvements in tidal streams. Results suggest that Florida is spending much more on stream restoration than previously documented. Between 1979 and 2015, the mean and median stream restoration project costs in Florida were $15.4 million and $180 000, respectively, indicating a strongly skewed distribution because of the large Kissimmee River restoration project in central Florida. This work highlights the need for, and utility of, statewide and national restoration databases to improve restoration tracking. This need will become increasingly critical as more stringent water quality and habitat mitigation rules are implemented across the country. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献