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REDUCTION OF STILLING BASIN LENGTH WITH TALL END SILL

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Journal of Hydrodynamics 2011年第4期23卷 498-502页

作者： FATHI-MOGHADAM Manoochehr HAGHIGHIPOUR Sadegh LASHKAR-ARA babak AGHTOUMAN Peyman Department of Hydraulic Structures Shahid Chamran University Department of Civil Engineering Jundishapur University of Technology Soil Conservation and Watershed Management Research Institute

Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction. The case with a single tall sill was simulated in a horizontal flume downstream of a sluice gate. Results of experiments are compared with the classical hydraulic jump, and significant effect of tall sill on dissipation of energy in shorter distance was confirmed. Furthermore, the generated jumps were classified based on the ratio of sill height to basin length, and a simple design criterion was proposed to estimate the basin length for a desired jump and particular inflow.

关键词： forced hydraulic jump energy dissipater sill stilling basin length

Enhanced Ionic Accessibility of Flexible MXene Electrodes Produced by Natural Sedimentation

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Nano-Micro Letters 2020年第7期12卷 145-155页

作者： Ning Sun Zhaoruxin Guan Qizhen Zhu babak Anasori Yury Gogotsi Bin Xu State Key Laboratory of Organic-Inorganic Composites Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China Department of Materials Science and Engineering and A.J.Drexel Nanomaterials Institute Drexel UniversityPhiladelphiaPA 19104USA Department of Mechanical and Energy Engineering Integrated Nanosystems Development InstitutePurdue School of Engineering and TechnologyIndiana University-Purdue University IndianapolisIndianapolisIN 46202USA

MXene nanosheets have been used for preparing highly flexible integrated electrodes due to their two-dimensional(2D)morphology,flexibility,high conductivity,and abundant functional ***,restacking of 2D nanosheets inhibits the ion transport in MXene electrodes,limiting their thickness,rate performance,and energy storage ***,we employed a natural sedimentation method instead of the conventional vacuum-assisted filtration to prepare flexible Ti3C2TxMXene films with enlarged interlayer spacing,which facilitates the access of the lithium ions to the interlayers and thus leads to a greatly enhanced electrochemical *** naturally sedimented flexible film shows a double lithium storage capacity compared to the conventional vacuum-filtered MXene film,along with improved rate performance and excellent cycle stability.

关键词： MXene Natural sedimentation Vacuum filtration Interlayer spacing Li-storage

Prediction of TBM jamming risk in squeezing grounds using Bayesian and artificial neural networks

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 21-31页

作者： Rohola Hasanpour Jamal Rostami Jürgen Schmitt Yilmaz Ozcelik babak Sohrabian Institute for Tunneling and Construction Management Ruhr-University BochumBochumGermany Department of Mining Engineering Colorado School of MinesGoldenUSA Department of Civil Engineering Darmstadt University of Applied ScienceDarmstadtGermany Department of Mining Engineering Hacettepe UniversityAnkaraTurkey Faculty of Mining and Metallurgical Engineering Urmia University of TechnologyUrmiaIran

This study presents an application of artificial neural network(ANN)and Bayesian network(BN)for evaluation of jamming risk of the shielded tunnel boring machines(TBMs)in adverse ground conditions such as squeezing *** analysis is based on database of tunneling cases by numerical modeling to evaluate the ground convergence and possibility of machine *** results of initial numerical analysis were verified in comparison with some case studies.A dataset was established by performing additional numerical modeling of various scenarios based on variation of the most critical parameters affecting shield *** includes compressive strength and deformation modulus of rock mass,tunnel radius,shield length,shield thickness,in situ stresses,depth of over-excavation,and skin friction between shield and *** the dataset,an ANN was trained to predict the contact pressures from a series of ground properties and machine ***,the continuous and discretized BNs were used to analyze the risk of shield *** results of these two different BN methods are compared to the field observations and summarized in this *** developed risk models can estimate the required thrust force in both *** BN models can also be used in the cases with incomplete geological and geomechanical properties.

关键词： Bayesian network(BN) Artificial neural network(ANN) Shielded tunnel boring machine(TBM) Jamming risk Numerical simulation Squeezing ground

On the application of artificial bee colony (ABC) algorithm for optimization of well placements in fractured reservoirs;efficiency comparison with the particle swarm optimization (PSO) methodology

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Petroleum 2016年第1期2卷 79-89页

作者： Behzad Nozohour-leilabady babak Fazelabdolabadi Department of Petroleum Engineering International Campus of the University of TehranKish IslandIran Institute of Enhanced Oil Recovery Centre of Exploration and Production Studies and ResearchResearch Institute of Petroleum Industry(RIPI)TehranIran

The application of a recent optimization technique,the artificial bee colony(ABC),was investigated in the context of finding the optimal well *** ABC performance was compared with the corresponding results from the particle swarm optimization(PSO)algorithm,under essentially similar *** of out-of-boundary solution vectors was accomplished via the Periodic boundary condition(PBC),which presumably accelerates convergence towards the global *** searches were initiated from several random staring points,to minimize starting-point dependency in the established *** optimizations were aimed at maximizing the Net Present Value(NPV)objective function over the considered oilfield production *** deal with the issue of reservoir heterogeneity,random permeability was applied via normal/uniform distribution *** addition,the issue of increased number of optimization parameters was address,by considering scenarios with multiple injector and producer wells,and cases with deviated wells in a real reservoir *** typical results prove ABC to excel PSO(in the cases studied)after relatively short optimization cycles,indicating the great premise of ABC methodology to be used for well-optimization purposes.

关键词： Artificial bee colony(ABC) Particle swarm optimization(PSO) Well placement

Reducing deep learning network structure through variable reduction methods in crop modeling

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Artificial Intelligence in Agriculture 2021年第1期5卷 196-207页

作者： babak Saravi A.Pouyan Nejadhashemi Prakash Jha Bo Tang Department of Biosystems and Agricultural Engineering Michigan State UniversityEast LansingMI 48824USA Department of Plant Soil and Microbial Sciences Michigan State UniversityEast LansingMI 48824USA Feed the Future Innovation Lab for Collaborative Research on Sustainable Intensification Kansas State UniversityManhattanKS 66506USA Department of Electrical and Computer Engineering Mississippi State UniversityMS 39762USA

Crop models are widely used to predict plant growth,water input requirements,and ***,existing models are very complex and require hundreds of variables to perform *** to these shortcomings,large-scale applications of crop models are *** order to address these limitations,reliable crop models were developed using a deep neural network(DNN)–a new approach for predicting crop *** addition,the number of required input variables was reduced using three common variable selection techniques:namely Bayesian variable selection,Spearman's rank correlation,and Principal Component Analysis Feature *** reduced-variableDNN modelswere capable of estimating future crop yields for 10,000,000 differentweather and irrigation scenarios while maintaining comparable accuracy levels to the original model that used all input *** establish clear superiority of the methodology,the results were also compared with a very recent feature selection algorithm called min-redundancy max-relevance(mRMR).The results of this study showed that the Bayesian variable selection was the best method for achieving the aforementioned ***,the final Bayesian-based DNN model with a structure of 10 neurons in 5 layers performed very similarly(78.6%accuracy)to the original DNN cropmodel with 400 neurons in 10 layers,even though the size of the neural network was reduced by *** effort can help promote sustainable agricultural intensifications through the large-scale application of crop models.

关键词： Deep learning Artificial intelligent Variable reduction Crop modeling Yield prediction Irrigation

Biochemical response to lamivudine treatment in HBeAg negative chronic hepatitis B patients in Iran

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World Journal of Gastroenterology 2006年第26期12卷 4203-4205页

作者： Amir Houshang Mohammad Alizadeh Mitra Ranjbar babak Karimi Saeed Hatami Research Center for Gastroenterology and Liver Disease Shaheed Beheshti University of Medical Sciences TehranIran Infectious Disease Specialist Hamadan University of Medical Sciences and Health Services Iran General Practitioner Hamadan University of Medical Sciences and Health Services Iran

AIM： To study the effect of a one-year lamivudine regimen in patients with chronic hepatitis B. METHODS： Medical records of HBeAg negative hepatitis B patients who attended a hepatitis clinic in Tehran between March 2002-March 2004 were evaluated. The patients received 100 mg lamivudine tablets once daily for at least 12 mo. Liver enzymes and complete blood count were checked at baseline and the end of treatment （12th mo） and 6 mo after discontinuation of treatment. RESULTS： Of all patients, 24 were excluded. Of 71 patients left, 58 （81.7%） were men. Mean age of the patients was 38 ± 14 years. Mean level of ALT in serum was 1437 ± 205 nkat/L at baseline with a significant reduction at the end of treatment to a mean level of 723 ± 92 nkat/L （P = 0.002）. In 38 patients （53.5%）, the ALT level was normal after one-year treatment. Five patients （7.3%） relapsed （biochemically） within 6 mo after discontinuing lamivudine therapy （the patients with good end of treatment response）. Mean level of AST in serum was 1060 ± 105 nkat/L at baseline which decreased significantly to 652 ± 75 nkat/L at the end of treatment （P = 0.002）. CONCLUSION： Over half （53.5%） of chronic hepatitis B patients with HBeAg negative have normal liver enzyme level at 12-mo lamivudine therapy.

关键词： Chronic hepatitis B Lamivudine HBeAg

Numerical investigation of hydraulic characteristics and prediction of cavitation number in Shahid Madani Dam’s Spillway

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Journal of Groundwater Science and Engineering 2019年第4期7卷 323-332页

作者： babak Ghazi Rasoul Daneshfaraz Esmaeil Jeihouni Department of Civil Engineering Sofian BranchIslamic Azad UniversitySofianIran Department of Civil Engineering Faculty of EngineeringUniversity of MaraghehMaraghehIran

The prediction of the probability of cavitation occurrence to prevent serious damages in the spillways is the major concern for hydraulic engineers. In this research, the three-dimensional model of Shahid Madani Dam's spillway was simulated with the Flow 3D software and by the comparison of numerical model results with the experi- mental data, the probability of occurrence of the cavitation phenomenon has been investigated. The flow parameters including pressure, velocity, and water depth were calculated for three different flow rates of 495 m3/s, 705 m3/s and 2 205 m3/s respectively. The Renormalization Group (RNG) turbulence model was used to simulate current turbu- lence. Comparison of simulation results for pressure, velocity and water depth with the results of the experimental model with two statistical indices Root Mean Square Error (RMSE) and Coefficient of Determination (R2) showed that the numerical simulation results are in good consistency with experimental model. However, simulation results indicated that at any flow rates with a return period of 1 000 years, probable maximum flood and designed flow rates, the cavitation number is not lower than the critical cavitation number. Therefore, it is predicted that the cavitation phenomenon in Shahid Madani Dam's spillway will not happen.

关键词： Spillway Cavitation index Velocity Water depth Pressure distribution

Aminobenzenesulfonamide functionalized SBA-15 nanoporous molecular sieve: A new and promising adsorbent for preconcentration of lead and copper ions

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Journal of Environmental Sciences 2012年第7期24卷 1347-1354页

作者： Leila Hajiaghababaei babak Ghasemi Alireza Badiei Hassan Goldooz Mohammad Reza Ganjali Ghodsi Mohammadi Ziarani Department of Chemistry Islamic Azad UniversityShahre Rey Branch School of Chemistry College of ScienceUniversity of Tehran Center of Excellence in Electrochemistry Faculty of ChemistryUniversity of Tehran Department of Chemistry Alzahra University

A rapid method for the extraction and monitoring of nanogram level of Pbz＋ and Cuz＋ ions using uniform silanized mesopor （SBA-15） functionalized with aminobenzenesulfonamide groups and flame atomic absorption spectrometry （FAAS） is presented. Aminobenzenesulfonamide functionalized SBA-15 was synthesized according to procedure in the literature and the presence of organic groups in the silica framework was demonstrated by FT-IR spectra. The functionalized product showed the BET surface area 110 mZ/g and pore diameter 5. l nm, based on adsorption-desorption of N2 at 77 K. The effect of several variables such as （amount of adsorbent, stirring time, pH and presence of other ions in the medium） has been studied. Lead and copper were completely extracted at pH greater than 3 after stirring for 10 min. The maximum capacity of the adsorbent was found to be 191.3 ＋ 1.4 and 155.0 ＋ 1.0 ~xg of lead and copper ions/mg functionalized SBA-15, respectively. The preconcentration factor of the method was found to be 200. The detection limit of the technique was 3.4 and 0.4 ng/mL for Pb2＋ and Cuz＋, respectively. The applications of this methodology for real samples were examined by various water type, black tea and pepper samples.

关键词： aminobenzenesulfonamide functionalized SBA-15 preconcentration Pb2+ and Cu2+ions

Use of Selection Indices Based on Multivariate Analysis for Improving Grain Yield in Rice

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Rice science 2008年第4期15卷 303-310页

作者： Hossein SABOURI babak RABIEI Maryam FAZLALIPOUR Department of Plant Production Gonbad High Education Center Gorgan University of Agricultural Sciences & Natural Resources Department of Agronomy and Plant Breeding Giulan University

In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The traits of the parents (30 plants), F1 (30 plants) and F2 generations (492 individuals) were evaluated at the Rice Research Institute of Iran (RRII) during 2007. Heritabilities of the number of panicles per plant, plant height, days to heading and panicle exsertion were greater than that of grain yield. The selection indices were developed using the results of multivariate analysis. To evaluate selection strategies to maximize grain yield, 14 selection indices were calculated based on two methods (optimum and base) and combinations of 12 traits with various economic weights. Results of selection indices showed that selection for grain weight, number of panicles per plant and panicle length by using their phenotypic and/or genotypic direct effects (path coefficient) as economic weights should serve as an effective selection criterion for using either the optimum or base index.

关键词： rice (Oryza sativa) optimum index base index path analysis heritability grain yield selection index