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In vitro propagation of conifers using mature shoots

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Journal of Forestry Research 2018年第3期29卷 565-574页

作者： mostafa K.Sarmast Department of Horticultural Science Faculty of Plant Production Gorgan University of Agricultural Sciences and Natural Resources (GUASNR)

Micropropagation mostly leads to the production of innumerable true-to-type plants. However, establishing pathogen-free explants through in vitro culture requires a precise management of time for the exposure of explants to antimicrobial chemicals. The application of antimicrobial chemicals must also be managed to impose the least injury on explants. This review discusses the contributions of micropropagation procedures, explant types, subculture duration, media ingredients and plant growth regulators to the in vitro response of conifer explants. Even though regeneration from mature conifer explants such as mature shoots are laborious, the chances of variation, induced in vitro, are unlikely.

关键词： Conifers Decontamination Micropropagation Tissue culture

Multimodality image registration and fusion using neural network

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Journal of Harbin Institute of Technology(New Series) 2003年第3期10卷 235-240页

作者： mostafa G mostafa Aly A Farag Edward Essock Computer Vision and Image Processing Laboratory Dept. of Electrical and Computer Engineering University of Louisville Louisville KY 40292 USAComputer Vision and Image Processing Laboratory Dept. of Electrical and Computer Engineering University of Louisville Louisville KY 40292 USADept. of Psychology University of Louisville Louisville kY 40292 USA

Multimodality image registration and fusion are essential steps in building 3-D models from remotesensing data. We present in this paper a neural network technique for the registration and fusion of multimodali-ty remote sensing data for the reconstruction of 3-D models of terrain regions. A FeedForward neural network isused to fuse the intensity data sets with the spatial data set after learning its geometry. Results on real data arepresented. Human performance evaluation is assessed on several perceptual tests in order to evaluate the fusionresults.

关键词： data fusion image registration image interpolation neural network, 3-D model building

Neutronic design investigation of a liquid injection-based second shutdown system for a typical research reactor using MCNPX

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Nuclear Science and Techniques 2018年第3期29卷 51-60页

作者： Ehsan Boustani mostafa hassanzadeh Nuclear Science and Technology Research Institute (NSTRI) Reactor and Nuclear Safety School

Safety systems, built on state-of-the-art technology, are essential for achieving acceptable levels of plant safety to minimize hazards to the reactor and the general public. The second shutdown system(SSS) as an engineered safety feature and a part of the reactor protection system(RPS) is a means for rapidly shutting down a nuclear reactor, keeping it in a subcritical state and serving as a backup to the first shutdown system(FSS). In this research, one SSS with two types of optimum chamber designs is proposed that take into account the main current characteristic features of the Tehran research reactor with improvements over earlier designs. They are based on a liquid neutron absorber injection that is preferably different, diverse, and independent from the FSS based on the rod drop mechanism. The major design characteristics of this SSS with two different chambers were investigated using MCNPX 2.6.0 code. The performed calculations showed that the designed SSS is a reliable shutdown system, assuring an appropriate shutdown margin and injection time, with no significant effects on the effective delayed neutron fraction while causing minimal variations to the core structure. Further, the reasonable financial cost and the prolongation of the operation cycle are additional advantages of this design.

关键词： Tehran research reactor Second shutdown system Nuclear safety Design criteria MCNPX code

Biodiversity of arbuscular mycorrhizal fungi in Amygdalus scoparia Spach plantations and a natural stand

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Journal of Forestry Research 2017年第6期28卷 1203-1211页

作者： Javad Mirzaei mostafa Moradi Department of Forest Science Faculty of AgricultureUniversity of Ilam P.O. Box 69315516 Ilam Iran Department of Forestry Faculty of Environment and Natural Resources Behbahan Khatam Al-Anbia University of Technology P.O. Box *** Behbahan KhuzestanIran

The biodiversity of arbuscular mycorrhizal fungi(AMF) was surveyed in the Kolm region of Iran in three adjacent sites, a natural stand, a 10-year-old and a 15-yearold plantation of Amygdalus scoparia. To date, there have been few studies of AMF biodiversity in Iran, especially in the western forests of the country. For this study, soil and root samples were taken from A. scoparia rhizosphere soil in spring and autumn. Almost half of the root length was colonized by AMF. We identified 13 AMF species belonging to Glomeraceae, Claroideoglomeraceae or Diversisporaceae. The three plantations differed in terms of soil electrical conductivity, organic C and P. Spore density was significant correlated with P concentration. Root length colonization was correlated only with soil *** diversity and richness were significantly correlated with soil N, P, organic C and spore density. AMF diversity in 15-year-old plantations was more similar to that in the natural stand than in the 10-year-old plantation. We confirmed that a 15-year-old plantation is not similar in terms of AMF colonization to natural stands. We conclude that more than 15 years are required for AMF colonization of plantations to resemble that of natural stands.

关键词： Arbuscular mycorrhizal Amygdalus scoparia Biodiversity

Chemical stability, thermal behavior, and shelf life assessment of extruded modified double-base propellants

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Defence Technology（防务技术） 2018年第1期14卷 70-76页

作者： Sherif Elbasuney Ahmed Fahd Hosam E.mostafa Sherif F.mostafa Ramy Sadek School of Chemical Engineering Military Technical College

Double base propellant suffers from lack of chemical stability; this could result in self ignition during storing. Modified double base(MDB) propellant based on stoichiometric binary mixture of oxidizermetal fuel(Ammonium perchlorate/Aluminum), and energetic nitramines(HMX) offered enhanced thrust as well as combustion characteristics. This study is devoted to evaluate the impact of such energetic additives on thermal behavior, chemical stability, and shelf life. Extruded MDB formulations were manufactured by extrusion process. Artificial aging at 80℃ for 28 days was conducted. Shelf life assessment was performed using Van't Hoff's equation. Quantification of evolved NOxgases with aging time was performed using quantitative stability tests. MDB formulation based on HMX demonstrated extended service life of 16 years compared with(AP/Al)-MDB which demonstrated 9 years. This finding was ascribed to the reactivity of AP with nitroglycerin with the formation of perchloric acid. Thermal behavior of aged MDB, exhibited an increase in heat released with time; this was ascribed to the autocatalytic thermal degradation during artificial aging. The increase in released heat by 31% was found to be equivalent to evolved NOx gases of 6.2 cm^3/5 g and 2.5 cm^3/1 g for Bergmann-Junk test, and Vacuum stability test respectively. This manuscript shaded the light on a novel approach to quantify evolved NOx gases to heat released with aging time. MDB based on HMX offered balanced ballistic performance,chemical stability, and service life.

关键词： Double-base Chemical stability Thermal behavior Artificial aging Shelf life assessment

Imputing missing values using cumulative linear regression

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CAAI Transactions on Intelligence Technology 2019年第3期4卷 182-200页

作者： Samih M. mostafa Faculty of Science Mathematics DepartmentComputer ScienceSouth Valley UniversityQena 83523Egypt

The concept of missing data is important to apply statistical methods on the dataset. Statisticians and researchers may end up to an inaccurate illation about the data if the missing data are not handled properly. Of late, Python and R provide diverse packages for handling missing data. In this study, an imputation algorithm, cumulative linear regression, is proposed. The proposed algorithm depends on the linear regression technique. It differs from the existing methods, in that it cumulates the imputed variables;those variables will be incorporated in the linear regression equation to filling in the missing values in the next incomplete variable. The author performed a comparative study of the proposed method and those packages. The performance was measured in terms of imputation time, root-mean-square error, mean absolute error, and coefficient of determination (R^2). On analysing on five datasets with different missing values generated from different mechanisms, it was observed that the performances vary depending on the size, missing percentage, and the missingness mechanism. The results showed that the performance of the proposed method is slightly better.

关键词： Imputing missing values cumulative linear regression statistical methods

Effects of Salinity and Potassium Application on Antioxidant Enzyme Activities and Physiological Parameters in Pearl Millet

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Agricultural Sciences in China 2011年第2期10卷 228-237页

作者： mostafa Heidari Parisa Jamshidi Faculty of Agronomy and Plant Breeding Department University of Zabol Department of Agronomy University of Zabol

A plot culture experiment was conducted in a greenhouse at University of Zabol,Iran,to study the effects of different salinity levels and potassium supply on pearl *** experiment was laid out in a completely randomized factorial design with three *** sulfate was used as the potassium *** rates of potassium treatments were 0,100,and 200 kg *** millet was subjected to different salinity levels（0,4,8,and 12 ds m-1） through addition of NaCl to irrigation *** showed that the increase in the salt concentration from control to 12 ds m-1 decreased grain yield（38.7%） of millet *** this study,we found a negative relationship between potassium and proline accumulation at vegetative（r2=-0.75＊＊） and reproductive stage（r2=-0.66＊＊） in millet *** stress remarkably elevated the activities of CAT and GPX antioxidant enzymes at vegetative and reproductive ***,potassium application had significant effect on grain yield and increased it about 10.6% at the highest salinity treatment（12 ds m-1）.Though,potassium treatment increased antioxidant activity in millet plants,it had no significant effect on proline content in *** treatment decreased potassium uptake but application potassium increased potassium content in leaves at two stages.

关键词： antioxidants enzymes ion content pearl millet potassium proline salinity

FIRST-ORDER METHODS FOR SOLVING THE OPTIMAL STATIC H∞-SYNTHESIS PROBLEM

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Journal of Computational Mathematics 2007年第6期25卷 672-689页

作者： El-Sayed M.E. mostafa Department of Mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, we consider the static output feedback （SOF） H∞-synthesis problem posed as a nonlinear semi-definite programming （NSDP） problem. Two numerical algorithms are developed to tackle the NSDP problem by solving the corresponding Karush- Kuhn-Tucker first-order necessary optimality conditions iteratively. Numerical results for various benchmark problems illustrating the performance of the proposed methods are given.

关键词： Static output feedback H∞-synthesis Semi-definite programming Nonlinear programming.

An Integrated Framework for Cloud Service Selection Based on BOM and TOPSIS

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Computers, Materials & Continua 2022年第8期72卷 4125-4142页

作者： Ahmed M.mostafa Computer and Systems Engineering Department Faculty of Engineering at HelwanHelwan UniversityCairo11795Egypt

Many businesses have experienced difficulties in selecting a cloud service provider(CSP)due to the rapid advancement of cloud computing services and the proliferation of *** independent criteria should be considered when evaluating the services provided by different *** is a case of multi-criteria decision-making(MCDM).This paper presents an integrated MCDM cloud service selection framework for determining the most appropriate service provider based on the best only method(BOM)and technique for order of preference by similarity to ideal solution(TOPSIS).To obtain the weights of criteria and the relative importance of CSPs based on each criterion,BOM performs pairwise comparisons of criteria and also for alternatives on each criterion,and TOPSIS uses these weights to rank cloud *** evaluation and validation of the proposed framework have been carried out through a use-case model to prove its efficiency and ***,the developed framework was compared with the analytical hierarchical process(AHP),a popular MCDM approach,based on two perspectives:efficiency and *** to the research results,the proposed framework only requires 25%of the comparisons needed for the AHP ***,the proposed framework has a CR of 0%,whereas AHP has 38%.Thus,the proposed framework performs better than AHPwhen it comes to computation complexity and consistency,implying that it is more efficient and trustworthy.

关键词： Cloud computing(CC) multiple-criteria decision-making(MCDM) cloud service providers(CSPs) analytical hierarchical process(AHP) the best only method(BOM) technique for order of preference by similarity to ideal solution(TOPSIS)