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Changes induced by osmotic stress in the morphology, biochemistry, physiology, anatomy and stomatal parameters of almond species(Prunus L. spp.) grown in vitro

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Journal of Forestry Research 2014年第3期25卷 523-534页

作者： Shakiba Rajabpoor Soghra kiani Karim Sorkheh Farahnaz Tavakoli Department of Biology Payam e Noor University Department of Agriculture Payam e Noor University Department of Agronomy and Plant Breeding Faculty of Agriculture Shahid Chamran University of Ahwaz Department of Plant Breeding and Biotechnology Faculty of Agriculture Shahrekord University

We investigated the influence of different levels of osmotic stress on growth and development in selected wild almond species （eight Prunus spp.） grown in vitro. The study, while endorsing the efficacy of in vitro screening of auxiliary buds of wild almond for osmotic stress tolerance, showed species variability in its response to osmotic stress. Osmotic stress reduced growth and development of all the species. How-ever, the putative tolerant Prunus spp. showed better performance than the putative susceptible genotypes. On average there was an 80% de-crease in shoot dry weight at -1.2 MPa. Reduction in shoot weight was more common in osmotic stress-susceptible species in the section labeled‘Euamygdalus’. The tolerant Prunus species produced smaller changes in biochemical responses than the sensitive cultivars for malondialdehyde content, catalase activity, relative permeability of protoplast membranes, and net photosynthetic rate. The tolerant species maintained cell integrity better than drought sensitive species. Wild almond species in the section labeled ‘Spartioides’ （Prunus arabica （Olivier） Neikle, Prunus glauca＆amp;nbsp;（Browicz） A.E. Murray, Prunus scoparia Spach） and ‘Lycioides’ （Pru-nus lycioides Spach, Prunus reuteri Bossi. et Bushe） were best adapted to osmotic stress. Increase in chlorophyll concentration and leaf thickness under high osmotic stress can be considered as preliminary selection parameters for osmotic stress tolerance in Prunus spp. The study con-firmed the efficacy of the in vitro method for screening of large number of genotypes for osmotic stress tolerance in wild almond species.

关键词： Prunus spp. proline osmotic stress leaf character malon-dialdehyde protoplast membrane permeability

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Dynamic characteristics of bubbling fluidization through recurrence rate analysis of pressure fluctuations

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Particuology 2013年第3期11卷 282-287页

作者： hossein Sedighikamal Reza Zarghami Multiphase Systems Department Oil and Gas Processing Centre of ExcellenceSchool of Chemical EngineeringCollege of EngineeringUniversity of Tehran

Pressure fluctuations signals of a lab-scale fiuidized bed （15 cm inner diameter and 2 m height） at different superficial gas velocities were measured. Recurrence plot （RP） and recurrence rate （RR）, and the simplest variable of recurrence quantification analysis （RQA） were used to analyze the pressure signals. Different patterns observed in RP reflect different dynamic behavior of the system under study. It was also found that the variance of RR （a2R） Could reveal the peak dominant frequencies （PDF） of different dynamic systems： completely periodic, completely stochastic, Lorenz system, and fluidized bed. The results were compared with power spectral density. Additionally, the diagram of σ^2RR provides a new technique for prediction of transition velocity from bubbling to turbulent fluidization regime.

关键词： Pressure fluctuations Fluidization Recurrence rate Peak dominant frequency Transition velocity Power spectral density

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Evaluation of seed quality and oil parameters in native Iranian almond(Prunus ***.) species

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Journal of Forestry Research 2015年第1期26卷 115-122页

作者： Soghra kiani Shakiba Rajabpoor Karim Sorkheh Sezai Ercisli Department of Agriculture Payame Noor University Department of Biology Payame Noor University Department of Agronomy and Plant Breeding Faculty of Agriculture Shahid Chamran University of Ahvaz Department of Horticulture Agricultural FacultyAtaturk University

We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds（Prunus L. spp.） accessions collected from different parts of Iran. There were significant differences in kernel weight and oil parameters. Accessions ranged from0.20 to 1.5 g in kernel weight, 0.2–3.0 mm in shell thickness, and 16–55 % in oil content. The predominant vegetable oil components of kernels were 4.6–9.5 % palmitic acid, 0.4–0.8 % palmitoleic acid, 1.0–3.4 % stearic acid,48.8–88.4 % oleic acid and 11.3–33.2 % linoleic *** acid was detected in 15 accessions. High heritability was recorded for all studied traits and was maximum for shell thickness（98.5 %） and minimum for oil content（97.1 %）. Maximum and minimum ‘Euclidean＇pair wise dissimilarities were 17.9 and 0.5, *** 40 accessions were grouped into two major clusters.

关键词： Genetic diversity Kernel quality Oil parameters Wild almond(Prunus L.spp.)

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3D object retrieval based on histogram of local orientation using one-shot score support vector machine

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Frontiers of Computer Science 2015年第6期9卷 990-1005页

作者： Vahid MEHRDAD hossein EBRAHIMNEZHAD Computer Vision Research Laboratory Electrical Engineering Faculty Sahand University of Technology Tabriz *** Iran

In this paper, a content based descriptor is pro- posed to retrieve 3D models, which employs histogram of local orientation （HLO） as a geometric property of the shape. The proposed 3D model descriptor scheme consists of three steps. In the first step, Poisson equation is utilized to define a 3D model signature. Next, the local orientation is calculated for each voxel of the model using Hessian matrix. As the final step, a histogram-based 3D model descriptor is extracted by accumulating the values of the local orientation in bins. Due to efficiency of Poisson equation in describing the models with various structures, the proposed descriptor is capable of discriminating these models accurately. Since, the inner vox- els have a dominant contribution in the formation of the de- scriptor, sufficient robustness against noise can be achieved. This is because the noise mostly influences the boundary vox- els. Furthermore, we improve the retrieval performance us- ing support vector machine based one-shot score （SVM-OSS） similarity measure, which is more efficient than the conven- tional methods to compute the distance of feature vectors. The rotation normalization is performed employing the prin- cipal component analysis. To demonstrate the applicability of HLO, we implement experimental evaluations of precision- recall curve on ESB, PSB and WM-SHREC databases of 3D models. Experimental results validate the effectiveness of the proposed descriptor compared to some current methods.

关键词： 3D model retrieval histogram of local orientation visual based shape descriptor poisson equation

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An effcient synthesis of functionalized tetrahydro-1H-indeno[2,1-c]pyridine derivatives by a PPh_3-promoted condensation reaction between acetylene esters and 1,3-dioxo-N-aryl-2,3-dihydro-1H-indene-2-carboxamides

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Chinese Chemical Letters 2013年第12期24卷 1095-1098页

作者： Mohammad hossein Mosslemin Nasim Shams hossein Esteghamat hossein Anaraki-Ardakani Department of Chemistry Yazd BranchIslamic Azad University Department of Chemistry Mahshahr BranchIslamic Azad University

A reaction between 1,3-dioxo-N-aryl-2,3-dihydro-lH-indene-2-carboxamides, dialkyl acetylenedicar- boxylates, and triphenylphosphine or trimethylphosphite is described as a simple and efficient method for the synthesis... 详细信息

关键词： Dialkyl acetylenedicarboxylates Triphenylphosphine Trimethylphosphites Tetrahydro-1H-indeno[2 1 -c]pyridine

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SYNTHESIS AND CHARACTERIZATION OF ORGANOSOLUBLE POLYAMIDES FROM QUINOXALINE BASED DIAMINE

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Chinese Journal of Polymer Science 2010年第2期28卷 147-155页

作者： hossein Mighani Mousa Ghaemy Department of Chemistry University of Golestan Department of Chemistry University of Mazandaran

Aromatic/aliphatic polyamides were synthesized from a diamine monomer, 2,3-bis-p-aminophenylquinoxaline （IV）, based on quinoxaline and various dicarboxylic acids of aliphatic, aromatic and heterocyclic. The diamine and polyamides were characterized by elemental analysis, FTIR and IH-NMR. The solubility of the polyamides was affected by the quinoxaline and heterocyclic groups in the polymer chain. They were all soluble in common organic solvents such as dimethylsulfoxide （DMSO）, N,N-dimethylformamide （DMF） and N-methylpyrolidone （NMP）. The polyamides showed inherent viscosity in the range of 0.25-0.3 dL/g in DMSO at 25℃ and good thermal stability with the char yields in the range of 65%-82% at 600℃ in nitrogen.

关键词： Quinoxaline Polyamides Solubility Thermal stability

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HBIR: Hypercube-Based Image Retrieval

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Journal of Computer Science & Technology 2012年第1期27卷 147-162页

作者： hossein Ajorloo Abolfazl Lakdashti Department of Computer Engineering Sharif University of Technology Tehran Iran University College of Rouzbahan Sari Iran

In this paper, we propose a mapping from low level feature space to the semantic space drawn by the users through relevance feedback to enhance the performance of current content based image retrieval （CBIR） systems. The proposed approach makes a rule base for its inference and configures it using the feedbacks gathered from users during the life cycle of the system. Each rule makes a hypercube （HC） in the feature space corresponding to a semantic concept in the semantic space. Both short and long term strategies are taken to improve the accuracy of the system in response to each feedback of the user and gradually bridge the semantic gap. A scoring paradigm is designed to determine the effective rules and suppress the inefficient ones. For improving the response time, an HC merging approach and, for reducing the conflicts, an HC splitting method is designed. Our experiments on a set of 11 000 images from the Corel database show that the proposed approach can better describe the semantic content of images for image retrieval with respect to some existing approaches reported recently in the literature. Moreover, our approach can be better trained and is not saturated in long time, i.e., any feedback improves the precision and recall of the system. Another strength of our method is its ability to address the dynamic nature of the image database such that it can follow the changes occurred instantaneously and permanently by adding and dropping images.

关键词： image retrieval relevance feedback rule base hypercube (HC)

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SYNTHESIS AND APPLICATIONS OF CROSS-LINKED POLY(DIALLYLDIMETHYL AMMONIUM CHLORIDE) AND ITS DERIVATIVE COPOLYMERS AS EFFICIENT PHASE TRANSFER CATALYST FOR NUCLEOPHILIC SUBSTITUTION REACTIONS

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Chinese Journal of Polymer Science 2011年第2期29卷 165-172页

作者： hossein Mahdavi Mahdi Mahmoudian School of Chemistry University College of ScienceUniversity of TehranTehranIran

Cross-linked poly（diallyldimethylammonium chloride） and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange *** additi... 详细信息

关键词： Poly(diallyldimethylammonium chloride) Phase transfer catalyst Nucleophilic substitution reaction Halogen exchange reaction

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Developing an engineering-statistical model for estimating aerodynamic coefficients of helicopter fuselage

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Chinese Journal of Aeronautics 2017年第1期30卷 175-185页

作者： hossein Sheikhi Abas Saghaie Department of Industrial Engineering Science and Research Branch Islamic Azad University

The design of the geometric shape of a helicopter fuselage poses a serious challenge for designers. The most important parameter in determining the shape of the helicopter fuselage is its aerodynamic coefficients. These coefficients are determined using two methods： wind tunnel test and computational fluid dynamics（CFD） simulation. The first method is expensive, time-consuming and limited. In addition, estimates in regions away from data can be poor. The second method,due to the limitations of numerical solution, the number of nodes and the used solution, is often inaccurate. In this paper, with the aim of accelerating the design process and achieving results with reasonable engineering accuracy, an engineering-statistical model which is useful for estimating the aerodynamic coefficients was developed, which mitigated the drawbacks of these two ***, by combining CFD simulation and regression techniques, an engineering model was presented for the estimation of aerodynamic coefficients. Then, by using the data from a wind tunnel test and implementation of statistical adjustment, the engineering model was modified and an engineering-statistical model was obtained. By spending less time and cost, the final model provided the aerodynamic coefficients of a helicopter fuselage at the desired angles of attack with reasonable accuracy. Finally, three numerical examples were provided to illustrate the application of the proposed model. Comparative results demonstrate the effectiveness of the engineering-statistical model in estimating the aerodynamic coefficients of a helicopter fuselage.

关键词： Aerodynamic coefficients Computaticnal fluid dynamics (CFD) Engineering-statistical model Helicopter fuselage Wind tunnel test

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Attitude Control of a Quadrotor with Optimized PID Controller

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Intelligent Control and Automation 2013年第3期4卷 335-342页

作者： hossein Bolandi Mohammad Rezaei Reza Mohsenipour hossein nemati S. M. Smailzadeh East Tehran (Qiam Dasht) Branch Islamic Azad University Tehran Iran Electrical Engineering Department Iran University of Science and Technology Tehran Iran

A new approach to control, stabilization and disturbance rejection of attitude subsystem of quadrotor is presented in this article. Analytical method is used to tune conventional structure of PID controller. SISO approach is implemented for control structure to achieve desired objectives. The performance of the designed control structure is evaluated through time domain factors such as overshoot, settling time and integral error index, and robustness. A comparison is done between designed controller and back-step controller applied to main model of quadrotor. The results of simulation show the effectiveness of designed control scheme.

关键词： Modeling Optimization PID Control Quadrotor

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