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Estimating oak forest parameters in the western mountains of Iran using satellite-based vegetation indices

Journal of Forestry Research 2020年第2期31卷 541-552页

作者： adel Nouri Bahman Kiani Mohammad Hossein Hakimi Mohammad Hossein Mokhtari Department of Forest Sciences Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran Department of Desert Management Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran

Remote sensing is an important tool for studying and modeling forest *** indices obtained from Landsat-8 remotely sensed data were used to estimate the forest parameters in the western mountains of *** sample points were selected on the map of Bayangan County,Kermanshah province,*** each point,a cluster of five rectangular plots of 8100 m2 and 200 m apart was *** clusters were primarily sampled to determine the variance of the forest *** coefficient of variation was used as a criterion for sample *** density,canopy cover and basal area per hectare were calculated for each *** indices were extracted fromthe Landsat-8 images for each *** linear and nonlinear regressions were conducted to develop the *** models were validated using an independent data *** of model parameters was statistically *** results showed that Normalized difference vegetation index(NDVI)and Transformed normalized difference vegetation index(TNDVI)followed by Simple ratio vegetation index(SRVI)were the best predictors,explaining up to 91%of the variations with high *** NDVI,Soil adjusted vegetation index 2(SAVI2)and SRVI,the cubic model was more appropriate than the linear model for predicting the forest *** this model,the R-square value increased while NRMSE decreased *** Infrared percentage vegetation index(IPVI),the quadratic model was better,but,for other vegetation indices,nonlinear models were not superior to linear ***,it can be concluded that Landsat-8 imagery is suitable for predicting forest parameters in the oak forests of western *** course,large plots must be selected,and pre-classification is necessary to gain accurate and precise estimations.

关键词： Basal area Canopy cover Density Landsat-8 Modeling

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Wheat Germ: An Overview on Nutritional Value, Antioxidant Potential and Antibacterial Characteristics

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Food and Nutrition Sciences 2015年第2期6卷 265-277页

作者： Awad A. mahmoud adel A. A. Mohdaly Nady A. A. Elneairy Food Science and Technology Faculty of Agriculture Fayoum University Al Fayoum Egypt Plant Production and Processing Department Food Management Course Agricultural Faculty University of Applied Sciences Weihenstephan-Triesdorf Triesdorf Germany

Wheat germ is a by-product derived from the wheat milling industry. Defatted wheat germ is the main by-product of the wheat germ in the oil extraction process. This study aims at development of efficient and low cost processing methods to transform these residues in added value co-product. In this study, wheat germ was analysed for its proximate composition, fatty acid composition, physical and chemical characteristics of wheat germ oil. The basic chemical composition analyses revealed high values of dry matter (87.37 g/100g FW), significant amounts of total protein and fat (27.69 and 8.99 g/100g FW, respectively) content and low ash content (3.08 g/100g FW). The quality of the extracted oils was assessed in terms of acid value, iodine value, saponification value, peroxide value, refractive index, and unsaponifiable matter. The fatty acid profile was found to be made up of linoleic followed by palmitic and oleic as the major fatty acids. Antioxidant properties and in vitro antibacterial activity of defatted wheat germ (DWG) extract were also determined. DWG, as a source of natural antioxidants and antibacterial, could be used to formulate nutraceuticals with potential applications to reduce the level of oxidative stress. The antioxidant potency of the DWG extracts could be the basis for its health promoting potential. The results showed that these by-products could be used as a source of bioactive compounds beneficial for health.

关键词： Antibacterial Activity Antioxidant Properties Defatted Wheat Germ Fatty Acid Wheat Germ Oil

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Computational investigation of hydraulic performance variation with geometry in gabion stepped spillways

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Water Science and Engineering 2019年第1期12卷 62-72页

作者： Dominic E.Reeve Ali adel Zuhaira Harshinie Karunarathna College of Engineering Swansea University

Over recent years, there has been a clear increase in the frequency of reported flooding events around the world. Gabion structures offer one means of flood mitigation in dam spillways. These types of structures provide an additional challenge to the computational modeller in that flow through the porous gabions must be simulated. We have used a computational model to investigate the flow over gabion stepped spillways. The model was first validated against published experimental results. Then, gabion stepped spillways with four different step geometries were tested under the same conditions in order to facilitate inter-comparisons and to choose the best option in terms of energy dissipation. The results show that normal gabion steps can dissipate more energy than overlap, inclined, and pooled steps. An intensive set of tests with varying slope, stone size, and porosity were undertaken. The location of the inception point and the water depth at this point obtained from this study were compared with those from existing formulae. Two new empirical equations have been derived, on the basis of a regression analysis, to provide improved results for gabion stepped spillways.

关键词： Computational modelling Energy dissipation Gabion stepped spillways Inception point location Skimming flow

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The capability of Sentinel-2 image and FieldSpec3 for detecting lithium-containing minerals in central Iran

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Frontiers of Earth Science 2022年第3期16卷 678-695页

作者： Kazem RANGZAN Mostafa KABOLIZADEH Sajad ZAREIE adel SAKI Danya KARIMI Department of Remote Sensing and GIS Faculty of Earth SciencesShahid Chamran University of AhvazAhvaz ***Iran Department of Geology Faculty of Earth SciencesShahid Chamran University of AhvazAhvaz ***Iran

To date,there are very few studies about the spectroscopy of lithium-containing minerals(LCMs)in the scientific *** main objective of this study is to investigate the capability of Sentinel-2 image and FieldSpec3 spectro-radiometer in terms of mapping five important LCMs,including spodumene,lepidolite,amblygonite,petalite,and ***,first the FieldSpec3 spectro-radiometer was used to create the spectral curves of the ***,accurate spectral analysis and comparison of the studied LCMs were performed using The Spectral Geologist(TSG)and the Prism *** two software can show even slight difference in absorption features of different LCMs,which can discriminate and identify these ***-bearing rocks show absorption features at~365,~2200,and~2350 nm and reflective features at~550-770 *** features are consistent with Sentinel-2 ***,the created spectral curves were utilized for calibration of Sentinel-2 optical image to detect and map the potential zones of the rock units containing minerals mentioned above in a part of the central Iranian *** using the Spectral Angle Mapper(SAM)classifier module,the potential areas were *** of the five LCMs,petalite and spodumene showed more extensive coverage in the study *** speaking,the largest concentration of those LCMs can be seen in southern and centraleastern parts of the study *** comparison between spectral curves of reference and classified minerals confirmed the high capability of Sentinel-2 image for LCMs *** image classification results also confirmed the presence of the LCMs,but it cannot distinguish the LCMs type successfully.

关键词： FieldSpec3 spectro-radiometer lithium containing minerals Sentinel-2 ASTER Iran

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Adaptive Fault Tolerant Control of Multi-time-scale Singularly Perturbed Systems

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International Journal of Automation and computing 2018年第6期15卷 736-746页

作者： adel Tellili Nouceyba Abdelkrim Amina Challouf Mohamed Naceur Abdelkrim Research Unit MACS University of Gabes Gabes Tunisia Higher Institute of Industrial Systems at Gabes University of Gabes Gabes Tunisia Higher Institute of Technological Studies at Djerba Djerba Tunisia National School of Engineers of Gabes University of Gabes Gabes Tunisia

This paper studies the fault tolerant control, adaptive approach, for linear time-invariant two-time-scale and three-time-scale singularly perturbed systems in presence of actuator faults and external disturbances. First, the full order system will be controlled using v-dependent control law. The corresponding Lyapunov equation is ill-conditioned due to the presence of slow and fast phenomena. Secondly, a time-scale decomposition of the Lyapunov equation is carried out using singular perturbation method to avoid the numerical stiffness. A composite control law based on local controllers of the slow and fast subsystems is also used to make the control law ε-independent. The designed fault tolerant control guarantees the robust stability of the global closed-loop singularly perturbed system despite loss of effectiveness of actuators. The stability is proved based on the Lyapunov stability theory in the case where the singular perturbation parameter is sufficiently small. A numerical example is provided to illustrate the proposed method.

关键词： Singularly perturbed systems time scale decomposition adaptive fault tolerant control actuator fault Lyapunov equations

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Tumor necrosis factor-alpha -308G/A polymorphism and risk of hepatocellular carcinoma in hepatitis C virus-infected patients

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Chinese Journal of Cancer 2012年第1期31卷 29-35页

作者： Roba M.Talaat Ahmed A.Esmail Reda Elwakil adel A.Gurgis mahmoud I.Nasr Molecular Biology Departments Genetic Engineering and Biotechnology Research Institute(GEBRI)Menofia UniversitySadat 22857Egypt Roche Diagnostics Ain Shams UniversityCairo 11522Egypt Department of Tropical Medicine Ain Shams UniversityCairo 11522Egypt

Tumor necrosis factor-alpha (TNF-α) is an important cytokine in generating an immune response against infection with hepatitis C virus (HCV). The functions of TNF-α may be altered by single-nucleotide polymorphisms (SNPs) in its gene structure. We hypothesized that SNPs in TNF-α may be important in determining the outcome of an HCV infection. To test this hypothesis, we investigated the role of the polymorphism -308G/A, which is located in the promoter region of the TNF-α gene, in the progression of HCV infection in Egyptian patients using a quantitative real-time polymerase chain reaction (qRT-PCR). The distribution of this polymorphism and its impact on the serum level of TNF-α was compared between 90 HCV-infected patients [45 with HCV-induced cirrhosis and 45 with HCV-related hepatocellular carcinoma (HCC)] and 45 healthy Egyptian volunteers without any history of liver disease. Our results showed that at the TNF-α -308 position, the G/G allele was most common (78.5% ) in the study population, with the G/A and A/A alleles occurring less frequently (13.3% and 8.1% , respectively). Frequencies of G/G, G/A, and A/A genotypes were 87%, 7%, and 6% in patients with liver cirrhosis and were 94% , 4% , and 2% in patients with HCC, respectively. Serum levels of TNF-α were significantly higher in HCV-infected patients than in healthy controls, indicating that the TNF-α -308 polymorphism does not influence the production of TNF-α. The serum level of TNF-α was positively correlated with HCV infection. Taken together, these findings suggest that the TNF-α -308 polymorphism may not be a host genetic factor associated with the severity of HCV infection, but may be an independent risk factor for HCC.

关键词：肿瘤坏死因子-α 单核苷酸多态性丙型肝炎病毒病毒感染患者肝癌风险聚合酶链反应

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Thermal buckling behavior of laminated composite plates： a finite-element study

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Frontiers of Mechanical Engineering 2014年第1期9卷 41-49页

作者： Houdayfa OUNIS Abdelouahab TATI adel BENCHABANE Laboratoire de Grnie Energrtique et Matrriaux (LGEM) Universit6 deBiskra B.P. 145 Biskra 07000 Algeria

In this paper, the thermal buckling behavior of composite laminated plates under a uniform temperature distribution is studied. A finite element of four nodes and 32 degrees of freedom （DOF）, the bending and mechanical previously developed for buckling of laminated composite plates, is extended to investigate the thermal buckling behavior of laminated composite plates. Based upon the classical plate theory, the present finite element is a combination of a linear isoparametric membrane element and a high precision rectangular Hermitian element. The numerical implementation of the present finite element allowed the comparison of the numerical obtained results with results obtained from the literature： 1） with element of the same order, 2） the first order shear defo^ation theory, 3） the high order shear deformation theory and 4） the three- dimensional solution. It was found that the obtained results were very close to the reference results and the proposed element offers a good convergence speed. Furthermore, a parametrical study was also conducted to investigate the effect of the anisotropy of composite materials on the critical buckling temperature of laminated plates. The study showed that： 1） the critical buckling temperature generally decreases with the increasing of the modulus ratio EL/ET and thermal expansion ratio aT/aL, and 2） the boundary conditions and the orientation angles signifi- cantly affect the critical buckling temperature of laminated plates.

关键词： thermal buckling laminated composite plates,anisotropy critical buckling temperature finite-elementmethod high precision rectangular Hermitian element

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Mineralogical and geochemical characterization of the Wadi Natash volcanic field(WNVF),Egypt:Alkaline magmatism in a Late Cretaceous continental rift system

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Acta Geochimica 2024年第6期43卷 1169-1191页

作者： adel A.Surour Ahmed A.Madani Mohamed A.El-Sharkawi Department of Geological Sciences Faculty of ScienceGalala UniversityNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

The Wadi Natash volcanic field(WNVF)in the south of the Eastern Desert of Egypt is a typical example of well-preserved intraplate alkaline magmatism during the Late Cretaceous,i.e.,prior to the Oligo-Miocene Red Sea *** compiled stratigraphic sections at two sectors;namely East Gabal Nuqra and West Khashm Natash(WKN)where the volcanic flows are intercalated with the Turonian Abu Agag sandstone with occasional paleosols when volcanic activity is *** mantle xenoliths are encountered in the first sector whereas flows in the second sector are interrupted by trachyte plugs and ring *** a geochemical basis,the maifc melt originating from the lithospheric mantle beneath the WNVF practiced~5%partial melting of phlogopite-bearing garnet *** dominate in the two sectors and highly evolved(silicic)rocks are confined to the WKN *** of ancient Precambrian fractures following the NW-SE and ENE-WSW trends facilitated the ascend of Late Cretaceous mantle-derived alkaline ***,the WNVF developed at the eastern shoulder of the so-called"Kom Ombo-Nuqra-Kharit rift system"that represents a well-defined NW-trending intracontinental rift basin in the southern Eastern *** such a structural setup,the Natash volcanic are confined to half-grabens at the East Gabal Nuqra sector whereas the West Khashm Natash sector is subjected to extensional stresses that propagated *** WNVF is a typical example of fluvial clastics(Turonian)intercalation with rift-related alkaline volcanic rocks in northeast Africa.

关键词： Wadi Natash volcanic field Late Cretaceous Lithostratigraphy Intraplate rift Abu Agag sandstone Clastic facies

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The Dynamics and Control of the Fractional Forms of Some Rational Chaotic Maps

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Journal of Systems Science & Complexity 2020年第3期33卷 584-603页

作者： OUANNAS adel KHENNAOUI Amina-Aicha BENDOUKHA Samir WANG Zhen PHAM Viet-Thanh Laboratory of Mathematics Informatics and Systems(LAMIS)University of Larbi TebessiTebessa 12002Algeria Department of Mathematics and Computer Sciences University of Larbi Ben M'hidiOum El BouaghiAlgeria Department of Electrical Engineering College of EngineeringYanbuTaibah UniversitySaudi Arabia Shaanxi Engineering Research Center of Controllable Neutron Source School of ScienceXijing UniversityXi'an 710123China Faculty of Electrical and Electronic Engineering Phenikaa Institute for Advanced Study(PIAS)Phenikaa UniversityYen NghiaHa Dong districtHanoi 100000Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group167 Hoang NganHanoi 100000Vietnam

This paper proposes three fractional discrete chaotic systems based on the Rulkov,Chang,and Zeraoulia–Sprott rational *** dynamics of the proposed maps are investigated by means of phase plots and bifurcations *** stabilization schemes are proposed for each of the three maps and the convergence of the states is established by using the Lyapunov ***,a combination synchronization scheme is proposed whereby a combination of the fractional Rulkov and Chang maps is synchronized to the fractional Zeraoulia-Sprott *** results are used to confirm the findings of the paper.

关键词： Fractional discrete chaos fractional rational maps stabilization synchronization

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Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： Abdel-Aal MAbdel-Karim Mohamed MHamdy adel A.Surour Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metagabbros-diorites(MGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt.

关键词： Island arc assemblage Magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt

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