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Characterizing Spatial Variability of Soil Textural Fractions and Fractal Parameters Derived from Particle Size Distributions

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Pedosphere 2019年第2期29卷 224-234页

作者： Meysam MOHAMMADI Mahmoud SHABANPOUR Mohammad Hossein MOHAMMADI nasser DAVATGAR Department of Soil Science Faculty of Agriculture University of Guilan Department of Soil Science Faculty of Agricultural Engineering and Technology University of Tehran Department of Soil Science Research Institute of Soil and Water

Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size *** to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture.

关键词： fractal dimension geometric mean diameter geostatistical approach physical property semivariogram model statistical correlation

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Enhancement of the transfection efficiency of DNA into Crocus sativus L. cells via PEI nanoparticles

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Journal of Integrative Agriculture 2018年第8期17卷 1768-1778页

作者： Behnam Firoozi nasser Zare Omid Sofalian Parisa Sheikhzade-Mosadegh Department of Agronomy and Plant Breeding Faculty of Agriculture and Natural Resources University of Mohaghegh Ardabili

Over the past decade, several natural and synthetic cationic polymers have been utilized for gene delivery into cells. Among them, polyethylenimine(PEI) was used for gene therapy successfully. The present study investigated the effect of PEI and ultrasound waves on ssD NA delivery into saffron cells. Gel retardation, dynamic light scattering(DLS) and scanning electron microscopy(SEM) assays were employed to determine the physicochemical properties of PEI/f-DNA polyplex(complex of PEI and fluorescently labeled DNA). Moreover, the cytotoxicity of PEI, PEI/f-DNA polyplex and ultrasound were investigated on saffron cells at different concentrations. The gel retardation results indicated that the formation and neutralization of the PEI/f-DNA polyplex were completed at N/P=5. The particle size distribution of the polyplexes was from 50 to 122 nm. The experimental results revealed that the cytotoxicity of the PEI/f-DNA polyplex was lower than that of PEI alone, hence the cells showed both dose-and exposure duration-dependent responses. Furthermore, the viability of saffron cells declined extremely after 5 and 10 min sonication but this reduction was not significant at 2 min exposure duration. The results also indicated that the combined utilization of ultrasound and PEI nanoparticles increased the transfection efficiency of saffron cells up to two times higher than those obtained by PEI or ultrasound separately.

关键词： PEI/f-DNA polyplex plant cell transfection saffron sonication

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Comparative studies on numerical sensitivity of different scenarios of enhanced oil recovery by water-alternating-gas(CO_(2))injection

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Petroleum Research 2023年第4期8卷 505-513页

作者： Saddam Mohammed Mohammed nasser Achinta Bera Vivek Ramalingam School of Energy Technology Pandit Deendayal Energy UniversityGandhinagarGujarat382007India

Enhanced oil recovery by CO_(2) injection technology(CO_(2)-EOR)plays a crucial role in enhancing oil production and the permanent sequestration of anthropogenic CO_(2) in depleted oil ***,the availability of CO_(2) in oil field locations and its mobility in contrast with reservoir fluids are prime challenges in CO_(2)-*** cost of CO_(2) and its availability at the oil fields has prompted investigations on efficient injection of CO_(2) at the fields to achieve the best sweep efficiency *** strategies such as water-alternating-gas(WAG),simultaneous vertical and horizontal WAG,simultaneous water injection into the aquifer and vertical WAG,water and gas injection simultaneously but separately(SS-WAG),and water and gas injection simultaneously but not separately(SNS-WAG)play a significant role,as well as the purity of CO_(2).In this work,the significance of the above criteria was investigated indi-vidually and in *** coupled sequence of injection rate,soaking time,WAG ratio,and purity of injected CO_(2) for enhancement of oil production were delineated.A realistic reservoir simulation model conceptualizing the CO_(2)-EOR system with five spot injection patterns was developed by the company *** history-matched model that was developed was used to investigate the sensitivity of the coupled effects to the criteria listed above on oil *** investigations quantitatively emphasized that purity and soaking time of CO_(2) have an inverse effect in the oil production rate and that SNS-WAG resulted in a better oil production rate than SS-WAG.

关键词： Water-alternating-gas Enhanced oil recovery Sensitivityanalysis Modelingand simulation Simultaneouslybut not separately water-alternating-gas(SS-WAG) Simultaneously pressure maintenance and WAG

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NON-EXISTENCE FOR FRACTIONALLY DAMPED FRACTIONAL DIFFERENTIAL PROBLEMS

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Acta Mathematica Scientia 2017年第1期37卷 119-130页

作者： Mohnmmed D,KASSIM Khaled M.FURATI nasser-eddine TATAR Department of Mathematics and Statistics King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia

In this paper, we are concerned with a fractional differential inequality containing a lower order fractional derivative and a polynomial source term in the right hand side. A non-existence of non-trivial global solutions result is proved in an appropriate space by means of the test-function method. The range of blow up is found to depend only on the lower order derivative. This is in line with the well-known fact for an internally weakly damped wave equation that solutions will converge to solutions of the parabolic part.

关键词： nonexistence global solution fractional differential equation Riemann-Liouvillefractional integral and fractional derivative

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Clinical and cost impact of intravenous proton pump inhibitor use in non-ICU patients

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World Journal of Gastroenterology 2010年第8期16卷 982-986页

作者： Soumana C nasser Jeanette G Nassif Hani I Dimassi Department of Pharmacy Practice School of PharmacyLebanese American University

AIM:To assess the appropriateness of the indication and route of administration of proton-pump-inhibitors (PPIs) and their associated cost impact. METHODS:Data collection was performed prospec-tively during a 6-mo period on 340 patients who re-ceived omeprazole intravenously during their hospital stay in non-intensive care floors. Updated guidelines were used to assess the appropriateness of the indication and route of administration. RESULTS:Complete data collection was available for 286 patients which were used to assess intravenous (IV) PPIs utilization. Around 88% of patients were receiving PPIs for claimed stress ulcer prophylaxis (SUP) indication; of which,only 17% met the guideline criteria for SUP indication,14% met the criteria for non-steroidal-anti-inflammatory drugs-induced ulcer prophylaxis,while the remaining 69% were identifi ed as having an unjustified indication for PPI use. Theinitiation of IV PPIs was appropriate in 55% of pa-tients. Half of these patients were candidates for switching to the oral dosage form during their hos-pitalization,while only 36.7% of these patients were actually switched. The inappropriate initiation of PPIs via the IV route was more likely to take place on the medical floor than the surgical floor (53% vs 36%,P = 0.003). The cost analysis associated with the appro-priateness of the indication for PPI use as well as the route of administration of PPI revealed a possible saving of up to $17 732.5 and $14 571,respectively. CONCLUSION:This study highlights the over-utili-zation of IV PPIs in non-intensive care unit patients. Restriction of IV PPI use for justified indications and route of administration is recommended.

关键词： Cost saving Lebanon Non-intensive care unit patients Omeprazole Over-utilization Proton-pump-inhibitors Stress ulcer prophylaxis

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Simultaneous knowledge-based identification and optimization of PHEV fuel economy using hyper-level Pareto-based chaotic Lamarckian immune algorithm, MSBA and fuzzy programming

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International Journal of Intelligent Computing and Cybernetics 2015年第1期8卷 2-27页

作者： Ahmad Mozaffari nasser L.Azad Alireza Fathi Systems Design Engineering Department University of WaterlooWaterlooCanada Department of Mechanical Engineering Babol University of TechnologyBabolIran

Purpose–The purpose of this paper is to probe the potentials of computational intelligence(CI)and bio-inspired computational tools for designing a hybrid framework which can simultaneously design an identifier to capture the underlying knowledge regarding a given plug-in hybrid electric vehicle’s(PHEVs)fuel cost and optimize its fuel consumption ***,the current investigation aims at elaborating the effectiveness of Pareto-based multiobjective programming for coping with the difficulties associated with such a tedious automotive engineering ***/methodology/approach–The hybrid intelligent tool is implemented in two different *** hyper-level algorithm is a Pareto-based memetic algorithm,known as the chaos-enhanced Lamarckian immune algorithm(CLIA),with three different objective *** a hyper-level supervisor,CLIA tries to design a fast and accurate identifier which,at the same time,can handle the effects of uncertainty as well as use this identifier to find the optimum design parameters of PHEV for improving the fuel ***–Based on the conducted numerical simulations,a set of interesting points are ***,it is observed that CI techniques provide us with a comprehensive tool capable of simultaneous identification/optimization of the PHEV operating *** is concluded that considering fuzzy polynomial programming enables us to not only design a proper identifier but also helps us capturing the undesired effects of uncertainty and measurement noises associated with the collected ***/value–To the best knowledge of the authors,this is the first attempt at implementing a comprehensive hybrid intelligent tool which can use a set of experimental data representing the behavior of PHEVs as the input and yields the optimized values of PHEV design parameters as the output.

关键词： Artificial immune system Fuzzy logic Knowledge acquisition Function approximation System identification Evolutionary computation

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A Note on the Generalized and Universal Associated Legendre Equations

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Communications in Theoretical Physics 2018年第7期69卷 19-24页

作者： Keegan L.A.Kirk Kyle R.Bryenton nasser Saad School of Mathematical & Computational Sciences University of Prince Edward Island

A class of second-order differential equations commonly arising in physics applications are considered,and their explicit hypergeometric solutions are provided. Further, the relationship with the Generalized and Universal Associated Legendre Equations are examined and established. The hypergeometric solutions, presented in this work,will promote future investigations of their mathematical properties and applications to problems in theoretical physics.

关键词： universal associated Legendre polynomials generalized associated Legendre equation hypergeo-metric series exact solutions

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Calibration of catalyst temperature in automotive engines over coldstart operation in the presence of different random noises and uncertainty： Implementation of generalized Gaussian process regression machine

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Frontiers of Mechanical Engineering 2015年第4期10卷 405-412页

作者： nasser L. AZAD Ahmad MOZAFFARI Systems Design Engineering Department University of WaterlooWaterloo N2L 3G1 Canada

The main scope of the current study is to develop a systematic stochastic model to capture the undesired uncertainty and random noises on the key parameters affecting the catalyst temperature over the coldstart operation of automotive engine systems. In the recent years, a number of articles have been published which aim at the modeling and analysis of automotive engines＇ behavior during coldstart operations by using regression modeling methods. Regarding highly nonlinear and uncertain nature of the coldstart operation, calibration of the engine system＇s variables, for instance the catalyst temperature, is deemed to be an intricate task, and it is unlikely to develop an exact physics-based nonlinear model. This encourages automotive engineers to take advantage of knowledge-based modeling tools and regression approaches. However, there exist rare reports which propose an efficient tool for coping with the uncertainty associated with the collected database. Here, the authors introduce a random noise to experimentally derived data and simulate an uncertain database as a representative of the engine system＇s behavior over coldstart operations. Then, by using a Gaussian process regression machine （GPRM）, a reliable model is used for the sake of analysis of the engine＇s behavior. The simulation results attest the efficacy of GPRM for the considered case study. The research outcomes confirm that it is possible to develop a practical calibration tool which can be reliably used for modeling the catalyst temperature.

关键词： automotive engine calibration coldstart

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Auto-regressive multiple-valued logic neurons with sequential Chua’s oscillator back-propagation learning for online prediction and synchronization of chaotic trajectories

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International Journal of Intelligent Computing and Cybernetics 2015年第2期8卷 102-138页

Purpose–The purpose of this paper is to examine the structural and computational potentials of a powerful class of neural networks(NNs),called multiple-valued logic neural networks(MVLNN),for predicting the behavior of phenomenological systems with highly nonlinear *** are constructed based on the integration of a number of neurons working based on the principle of multiple-valued *** possess some particular features,namely complex-valued weights,input,and outputs coded by kth roots of unity,and a continuous activation as a mean for transferring numbers from complex spaces to trigonometric spaces,which distinguish them from most of the existing ***/methodology/approach–The presented study can be categorized into three *** the first part,the authors attempt at providing the mathematical formulations required for the implementation of ARX-based MVLNN(AMVLNN).In this context,it is indicated that how the concept of ARX can be used to revise the structure of MVLNN for online ***,the stepwise formulation for the simulation of Chua’s oscillatory map and multiple-valued logic-based BP are *** an analysis,some interesting characteristics of the Chua’s map,including a number of possible attractors of the state and sequences generated as a function of time,are ***–Based on a throughout simulation as well as a comprehensive numerical comparative study,some important features of AMVLNN are *** simulation results indicate that AMVLNN can be employed as a tool for the online identification of highly nonlinear dynamic ***,the results show the compatibility of the Chua’s oscillatory system with BP for an effective tuning of the synaptic *** results also unveil the potentials of AMVLNN as a fast,robust,and efficient control-oriented model at the heart of NMPC control ***/value–This study presents two innovative ***,the structure of MVLNN is mo

关键词： Real-time systems Learning Networked control Neural nets Chaotic systems Model predictive control

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Synthesis, spectral, optical and anti-inflammatory activity of complexes derived from 2-aminobenzohydrazide with some rare earths

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Journal of Rare Earths 2015年第7期33卷 758-764页

作者： nasser Mohammed Hosny El Sayed A.El Morsy Yousery E.Sherif Chemistry Department Faculty of Science Port-Said University Clinical Pharmacology Department Faculty of Medicine Mansoura University Pharmacology and Therapeutics Department Qassim College of Medicine Qassim University Department of Chemistry Faculty of Science and Arts Taibah University

Three new metal complexes derived from Er（Ⅲ）, Dy（Ⅲ） and Zr（Ⅳ） with 2-aminobenzohydrazide （ABH） were synthesized and characterized by elemental analyses, IR, ^1H-NMR, ES-MS and transmission electron microscopy （TEM）. The morphology and the particle size were determined by TEM. The results showed that the ligand acted as neutral bi-dentate coordinating to the metal ions through the carbonyl oxygen and amidic amino nitrogen. The aromatic amine group remained inert towards coordination. The optical band gap was measured and found to be 3.3, 3.5 and 4.3 eV for Er（Ⅲ）, Dy（Ⅲ） and Zr（Ⅳ）, respectively. The optical band gap values indicated a semi-conducting nature of the investigated complexes. The anti-inflammatory and analgesic activities of the tested compounds were determined and compared with standard meloxicam.

关键词： Er(Ⅲ) Dy(Ⅲ) Zr(Ⅳ) metal complexes optical band gap rare earths

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