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Comparison of Artificial Neural Networks,Geographically Weighted Regression and Cokriging Methods for Predicting the Spatial Distribution of Soil Macronutrients(N,P,and K)

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Chinese Geographical Science 2017年第5期27卷 747-759页

作者： samad EMAMGHOLIZADEH Shahin SHAHSAVANI Mohamad Amin ESLAMI 1.Department of Water and Soil Engineering Shahrood University of TechnologyShahrood361999-5161Iran

Soil macronutrients(i.e. nitrogen(N), phosphorus(P), and potassium(K)) are important soils components and knowing the spatial distribution of these parameters are necessary at precision agriculture. The purpose of this study was to evaluate the feasibility of different methods such as artificial neural networks(ANN) and two geostatistical methods(geographically weighted regression(GWR) and cokriging(CK)) to estimate N, P and K contents. For this purpose, soil samples were taken from topsoil(0–30 cm) at 106 points and analyzed for their chemical and physical parameters. These data were divided into calibration(n = 84) and validation(n = 22). Chemical and physical variables including clay, p H and organic carbon(OC) were used as auxiliary soil variables to estimate the N, P and K contents. Results showed that the ANN model(with coefficient of determination R^2 = 0.922 and root mean square error RMSE = 0.0079%) was more accurate compared to the CK model(with R^2 = 0.612 and RMSE = 0.0094%), and the GWR model(with R^2 = 0.872 and RMSE = 0.0089%) to estimate the N variable. The ANN model estimated the P with the RMSE of 3.630 ppm, which was respectively 28.93% and 20.00% less than the RMSE of 4.680 ppm and 4.357 ppm from the CK and GWR models. The estimated K by CK, GWR and ANN models have the RMSE of 76.794 ppm, 75.790 ppm and 52.484 ppm. Results indicated that the performance of the CK model for estimation of macro nutrients(N, P and K) was slightly lower than the GWR model. Also, the accuracy of the ANN model was higher than CK and GWR models, which proved to be more effective and reliable methods for estimating macro nutrients.

关键词： precision agriculture soil characteristics interpolation artificial neural networks geographically weighted regression Cokriging

Agrobacterium-Mediated Transformation of Rice: Constraints and Possible Solutions

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Rice science 2019年第3期26卷 133-146页

作者： Sulaiman MOHAMMED Azman Abd samad Zaidah RAHMAT Department of Biotechnology and Medical Engineering Faculty of Biosciences and Medical Engineering Universiti Teknologi Malaysia Department of Biological Sciences Faculty of Science Gombe State University

Genetic transformation of rice(Oryza sativa L.) by introducing beneficial traits is now a central research instrument in plant physiology and a practical tool for plant improvement. Many approaches are verified for stable introduction of foreign genes into the plant genome. The review examined the different constraints that limit the success of rice genetic transformation via Agrobacterium-mediated approach and suggested possible solutions. Explant identification, gene transfer technique and construct to tailor the integration, transgene expression without collateral to genetic damage and transformant selection are among the technical challenges affecting the rice transformation. Despite the contests, Agrobacteriummediated transformation system has been a better option for producing transgenic rice varieties because of its exact T-DNA processing and simple integration of low copy-number transgene. This information is necessary for improving the transformation system for recalcitrant rice varieties.

关键词： rice Agrobacterium-mediated transformation tissue culture gene transfer T-DNA integration

Experimental study of the velocity of density currents in convergent and divergent channels

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International Journal of Sediment Research 2014年第4期29卷 518-523页

作者： Hasan Torabi POUDEH samad EMAMGHOLIZADEH Manoocher Fathi-MOGHADAM Department of Water Engineering Lorestan of University Department of Water and Soil Engineering University of Shahrood Department of Hydraulic Structures Shahid Chamran University

The head velocity of the density current in the convergent and divergent channel is a key parameter for evaluating the extent to which suspended material travels,and for determining the type and distribution of sediment in the water *** study experimentally evaluated the effects of the reach degree of convergence and divergence on the head velocity of the density *** were conducted in the flume with 6.0 m long,0.72 m width and 0.6 m *** head velocity was measured at three convergent degrees(-8°;-12°;-26°),at three divergent degrees(8°;12°;26°) and two slopes(0.009,0.016) for various *** measured head velocity of the density current is compared with the head velocity of the density current in the constant cross section *** on non-dimensional and statistical analysis,relations as linear multiple regression are offered for predicting head velocity of the density current in the convergent,divergent and constant cross section *** the results of this research show that for the same slope and discharge,the head velocity of the density current in the convergent and divergent channel are greater and less than the head velocity of the constant cross section,respectively.

关键词： Density current Divergent and convergent channel Reservoir Sediment

Oxalic acid as a simple and efficient organocatalyst for three-component synthesis ofα-amino nitriles

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Chinese Chemical Letters 2011年第5期22卷 543-546页

作者： Seyed Mohammad Vahdat samad Khaksar Maryam Khavarpour Chemistry Department Islamic Azad UniversityAyatollah Amoli BranchP.O.Box 678AmolIran Chemical Engineering Department Islamic Azad UniversityAyatollah Amoli BranchP.O.Box 678AmolIran

A simple,efficient,and general method has been developed for the synthesis ofα-amino *** acid as a BrФnsted acid promotes the addition of TMSCN to various imines（generated in situ）.

关键词： Oxalic acid TMSCN BrФnsted acid α-Amino nitriles

Modeling of fluid-induced vibrations and identification of hydrodynamic forces on flow control valves

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Journal of Central South University 2015年第7期22卷 2596-2603页

作者： samad Mehrzad Ilgar Javanshir Ahmad Rahbar Ranji Seyyed Hadi Taheri Department of Maritime Engineering Science and Research Branch Islamic Azad University Young Researchers and Elite Club Tabriz Branch Islamic Azad University Department of Maritime Engineering Amirkabir University

Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.

关键词： flow-induced force hydrodynamic force finite element method(FEM) valve design fluid-structure interaction vibration

A Boosting Procedure for Variational-Based Image Restoration

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Numerical Mathematics(Theory,Methods and Applications) 2018年第1期11卷 49-73页

作者： samad Wali Zhifang Liu Chunlin Wu Huibin Chang School of Mathematical Sciences Nankai UniversityTianjinChina School of Mathematical Sciences Tianjin Normal UniversityTianjinChina

Variational methods are an important class of methods for general image *** technique has been shown capable of improving many image denoising *** paper discusses a boosting technique for general variation-al image restoration *** broadens the applications of boosting techniques to a wide range of image restoration problems,including not only denoising but also deblur-ring and *** particular,we combine the recent SOS technique with dynamic parameter to variational *** dynamic regularization parameter is motivated by Meyer’s analysis on the ROF *** each iteration of the boosting scheme,the variational model is solved by augmented Lagrangian *** convergence analy-sis of the boosting process is shown in a special case of total variation image denoising with a“disk”input *** have implemented our boosting technique for several im-age restoration problems such as denoising,inpainting and *** numerical results demonstrate promising improvement over standard variational restoration mod-els such as total variation based models and higher order variational model as total generalized variation.

关键词： Variational method image restoration total variation boosting augmented Lagrangian method

Geology and Mineral Chemistry of Gold Mineralization in Mirge-Naqshineh Occurrence(Saqez,NW Iran):Implications for Transportation and Precipitation of Gold

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 210-224页

作者： Golale ASGHARI samad ALIPOUR Hossein AZIZI Hassan MIRNEJAD Department of Geology Urmia University Mining Department Faculty of Engineering University of Kurdistan Department of Geology Faculty of Science University of Tehran

The Mirge-Naqshineh gold district is situated at northwest of Iran with a NW-trending brittle- ductile shear zone. It is hosted by Precambrian meta-sedimentary and meta-volcanic units traversed by mineralized quartz veins. In terms of cross-cutting relationships and sulfide content three types of quartz veins are identified in the region. Among those, parallel to bedding quartz vein （type I） is the main host for gold mineralization. Gold is found in three different forms： 1） submicrometer-size inclusions of gold in arsenian pyrite, 2） as electrum and 3） in the crystal lattice of sulfides （pyrite, galena and chalcopyrite）. Six types of pyrite （Pyl-Py6） were identified in this ore reserve. Py3 coexists with arsenopyrite and contains the greatest As-Au concentrations. There is a negative correlation between the As and S contents in Py2 and Py3, implying the substitution of sulfur by arsenic. Pyrites and mineralized quartz veins were formed via metamorphic-hydrothermal fluid and reflect the gold-transportation as Au（HS）2 under reducing and acidic conditions. The gold precipitation mainly controlled by crystallization of arsenian pyrite during fluid/rock interactions and variation offO2. The volcanic host rock has played an important role in gold concentration, as Py3 in this rock contains inclusion of gold particles, but gold is within the lattice of pyrite in phyllite or other units.

关键词： gold quartz veins mineral chemistry EPMA Mirge-Naqshineh Iran

Application of Geochemistry and VNIR Spectroscopy in Mapping Heavy Metal Pollution of Stream Sediments in the Takab Mining Area, NW of Iran

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2382-2394页

作者： Parisa PIROOZFAR samad ALIPOUR Soroush MODABBERI David COHEN Department of Geology Faculty of SciencesUrmia University School of Geology University of Tehran School of Biological Earth and Environmental SciencesNew South Wales University

This study considered the possibility of using visible and near infrared(VNIR) spectral absorption feature parameters(SAFPs) in predicting the concentration and mapping the distribution of heavy metals in sediments of the Takab area. In total, 60 sediment samples were collected along main streams draining from the mining districts and tailing sites, in order to measure the concentration of As, Co, V, Cu, Cr, Ni, Hg, Ti, Pb and Zn and the reflectance spectra(350–2500 nm). The quantitative relationship between SAFPs(Depth500 nm, R610/500 nm, R1344/778 nm, Area500 nm, Depth2200 nm, Area2200 nm, Asym2200 nm) and geochemical data were assessed using stepwise multiple linear regression(SMLR) and enter multiple linear regression(EMLR) methods. The results showed a strong negative correlation between Ni and Cr with Area2200 nm, a significant positive correlation between As and Asym2200 nm, Ni and Co with Depth2200 nm, as well as Co, V and total values with Depth500 nm. The EMLR method eventuated in a significant prediction result for Ni, Cr, Co and As concentrations based on spectral parameters, whereas the prediction for Zn, V and total value was relatively weak. The spatial distribution pattern of geochemical data showed that mining activities, along with the natural weathering of base metal occurrences and rock units, has caused high concentrations of heavy metals in sediments of the Sarough River tributaries.

关键词： heavy metals SAFPs VNIR spectroscopy multiple linear regression Takab Iran

Experimental study of the velocity of density currents in convergent and divergent channels

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International Journal of Sediment Research 2013年第2期28卷 254-259页

作者： Hasan Torabi POUDEH samad EMAMGHOLIZADEH Manoocher Fathi-MOGHADAM Department of Water Engineering Lorestan of University Department of Water and Soil Engineering Shahrood University of Technology Department of Hydraulic Structures Shahid Chamran University

The head velocity of the density current in the convergent and divergent channel is a key parameter for evaluating the extent to which suspended material travels,and for determining the type and distribution of sediment in the water *** study experimentally evaluated the effects of the reach degree of convergence and divergence on the head velocity of the density *** were conducted in the flume with 6.0 m long,0.72 m width and 0.6 m *** head velocity was measured at three convergent degrees(-8°;-12°;-26°),at three divergent degrees(8°;12°;26°) and two slopes(0.009,0.016) for various *** measured head velocity of the density current is compared with the head velocity of the density current in the constant cross section channel. Based on non-dimensional and statistical analysis,relations as linear multiple regression offered for prediction head velocity of the density current in the convergent,divergent and constant cross section *** the results of this research show that for the same slope and discharge,the head velocity of the density current in the convergent and divergent channel are greater and less than the head velocity of the constant cross section, respectively.

关键词： Density current Divergent and convergent channel Reservoir Sediment