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Quantifying major sources of uncertainty in projecting the impact of climate change on wheat grain yield in dryland environments

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Journal of Arid Land 2023年第5期15卷 545-561页

作者： reza DEIHIMFARD Sajjad RAHIMI-moghaddam Farshid JAVANSHIR Alireza PAZOKI Department of Agroecology Environmental Sciences Research InstituteShahid Beheshti UniversityTehran 19839–69411Iran Department of Production Engineering and Plant Genetics Faculty of Agriculture and Natural ResourcesLorestan UniversityKhorramabad 68151–44316Iran Department of Agrotechnology Yadegar-e-Imam Khomeini(RAH)Shahre Rey BranchIslamic Azad UniversityTehran 18151–63111Iran

Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and ***,there exists inherent uncertainty in such *** Circulation Models(GCMs)and future climate change scenarios(different Representative Concentration Pathways(RCPs)in different future time periods)are among the major sources of uncertainty in projecting the impact of climate change on crop grain *** study quantified the different sources of uncertainty associated with future climate change impact on wheat grain yield in dryland environments(Shiraz,Hamedan,Sanandaj,Kermanshah and Khorramabad)in eastern and southern *** five representative locations can be categorized into three climate classes:arid cold(Shiraz),semi-arid cold(Hamedan and Sanandaj)and semi-arid cool(Kermanshah and Khorramabad).Accordingly,the downscaled daily outputs of 29 GCMs under two RCPs(RCP4.5 and RCP8.5)in the near future(2030s),middle future(2050s)and far future(2080s)were used as inputs for the Agricultural Production Systems sIMulator(APSIM)-wheat *** of variance(ANOVA)was employed to quantify the sources of uncertainty in projecting the impact of climate change on wheat grain *** from 1980 to 2009 were regarded as the baseline *** projection results indicated that wheat grain yield was expected to increase by 12.30%,17.10%,and 17.70%in the near future(2030s),middle future(2050s)and far future(2080s),*** increases differed under different RCPs in different future time periods,ranging from 11.70%(under RCP4.5 in the 2030s)to 20.20%(under RCP8.5 in the 2080s)by averaging all GCMs and locations,implying that future wheat grain yield depended largely upon the rising CO2 *** results revealed that more than 97.22% of the variance in future wheat grain yield was explained by locations,followed by scenarios,GCMs,and their ***,at the semi-arid climate locations(Hamedan,S

关键词： wheat grain yield climate change Agricultural Production Systems sIMulator(APSIM)-wheat model General Circulation Models(GCMs) arid climate semi-arid climate Iran

On the prediction of filtration volume of drilling fluids containing different types of nanoparticles by ELM and PSO-LSSVM based models

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Petroleum 2022年第3期8卷 424-435页

作者： Aleksander Lekomtsev Amin Keykhosravi Mehdi Bahari moghaddam reza Daneshfar Omid Rezvanjou Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm KraiRussia Faculty of Petroleum and Natural Gas Engineering Sahand University of TechnologyTabrizIran Department of Petroleum Engineering Ahwaz Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AhwazIran

There is a direct link between the extent of formation damage and the filtration volume of the drilling fluids in hydrocarbon *** filtration volume can be diminished by adding different additives to the drilling ***,nanoparticles have been extensively used for enhancing the filtration characteristics of the drilling ***,there is no reliable model for investigating the influence of this class of additives on the performance of drilling *** in this study,two powerful tools ELM(extreme learning machine)and PSO-LSSVM(particle swarm optimization-least square support vector machine)are applied to determine the effect of various nanoparticles on the filtration *** assessment of the models is carried out by computing the statistical parameters,and it is found that ELM has a greater ability to predict the filtration volumes,while PSO-LSSVM performs satisfactorily *** model predictions and experimental results are in excellent agreement as suggested by the values of root mean squared error(RMSE=0.2459),coefficient of determination(R^(2)=0.999),and mean relative error(MRE=2.028%)for the *** statistical analysis shows that the suggested model can predict the filtration volume with great ***,through sensitivity analysis of the input parameters,it is found that for a specified nanoparticle,the filtration volume is highly influenced by nanoparticle concentration and it is the essential variable for the optimization process.

关键词： Nanoparticles Drilling mud Extreme learning machine Filtration volume Least square support vector machine

Gamma-ray shielding study of light to heavyweight concretes using MCNP-4C code

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Nuclear Science and Techniques 2017年第2期28卷 1-7页

作者： reza Bagheri Alireza Khorrami moghaddam Ali Yousefi Nuclear Fuel Cycle Research School (NFCRS) Nuclear Science and Technology Research Institute (NSTRI)Tehran 14155-1339 Iran Radiology Department Paramedical Faculty Mazandaran University of Medical Sciences SariMazandaran 14536-33143 Iran

In this work, linear and mass attenuation coefficients, half and tenth-value layers, effective atomic number and electron density of different types of concretes were determined at 316.51, 468.07, 511, 662, 1173 and 1332 keV using MCNP-4C code and Win XCom programs. The MCNP-4C and Win XCom results agreed well with each other, with differences of \±1.9%. The results agreed with available experimental data, too, with differences of \±6%.The MCNP-4C results showed better agreement with the experimental data than the Win XCom results. Also, it was found that the effective electron density of studied concretes varies in the range of(2.83–3.2) 9 10^(23)electron/g.

关键词： Concrete Shielding MCNP-4C WinXCom Mass attenuation coefficient Effective atomic number and electron density

Integration of Facility Location and Hypercube Queuing Models in Emergency Medical Systems

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Journal of Systems Science and Systems Engineering 2021年第4期30卷 495-516页

作者： Maryam Ghobadi Jamal Arkat Hiwa Farughi reza Tavakkoli-moghaddam Department of Industrial Engineering University of KurdistanSanandajIran School of Industrial Engineering College of EngineeringUniversity of TehranTehranIran

The purpose of emergency medical systems(EMS)is to save lives and reduce injuries with a quick response in *** performance of these systems is highly dependent on the locations of ambulances and the policy for dispatching them to the customers(i.e.,patients).In this study,two new mathematical models are presented to combine the decisions about the location and dispatching policy by integrating the location and hypercube queuing *** the presented models,the flow-balance equations of the hypercube queuing model are considered as the constraints of the location *** the first model,the status of each server is idle or busy at any moment,as in the classic hypercube queuing *** the second model,the travel time is considered independent of the on-scene time,and the status of each server is idle,busy,and traveling,or busy and serving a customer on the incident *** verify the models,some small-sized examples are first solved ***,an optimization framework based on the genetic algorithm is presented due to the complexity of the models for solving larger-sized *** approaches(i.e.,the exact and simulation-optimization)are used to extend the *** results demonstrate that the proposed optimization framework can obtain proper solutions compared to those of the exact ***,several performance measures are considered that can only be calculated using the second model.

关键词： Emergency medical system hypercube queuing system simulation-optimization genetic algorithm

A facile synthesis of high activity cube-like Pt/carbon composites for fuel cell application

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Frontiers in Energy 2017年第3期11卷 245-253页

作者： reza B. moghaddam Samaneh SHAHGALDI Xianguo LI Department of Mechanical and Mechatronics Engineering University of Waterloo Waterloo ON N2L 3G1 Canada

High activity catalyst with simple low-cost synthesis is essential for fuel cell commercialization. In this study, a facile procedure for the synthesis of cube-like Pt nanoparticle （PtCube） composites with high surface area carbon supports is developed by mixing precursor of Pt with carbon supports in organic batches, hence, one pot synthesis. The PtCube grow with Vulcan XC-72 or Ketjen black, respectively, and then treated for 5.5 h at 185℃ （i.e., Ptcube5.5/V and PtcubeS.5/K）. The resulting particle sizes and shapes are similar; however, Ptcube5.5/K has a larger electrochemical active surface area （EASA） and a remarkably better formic acid （FA） oxidation performance. Optimization of the PtCube/K composites leads to Ptcubelo/K that has been treated for 10 h at 185℃. With a larger EASA, Ptcubelo/K is also more active in FA oxidation than the other Ptcube/K composites. Impedance spectroscopy analysis of the temperature treated and asprepared （i.e., untreated） Ptcube/K composites indicates that PtCube10/K is less resistive, and has the highest limiting capacitance among the PtCube/K electrodes. Consistently, the voltammetric EASA is the largest for Ptcube 10/K. Furthermore, PtCube10/K is compared with two commercial Pt/C catalysts, Tanaka Kikinzoku Kogyo （TKK）, and Johnson Matthey （JM）Pt/C catalysts. The TKK Pt/C has a higher EASA than Ptcube10/K, as expected from their relative particles sizes （3-4 nm vs. 6-7 nm for PtcubelO/K）, however, Ptcube10/K has a significantly better FA oxidation activity.

关键词： synthesis cube-like Pt Pt/C composite,catalyst impedance

Groups with the same order and degree pattern

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Science China Mathematics 2012年第4期55卷 701-720页

作者： KOGANI-moghaddam Roya moghaddamFAR Ali reza Department of Mathematics K.N.Toosi University of Technology School of Mathematics Institute for Research in Fundamental Sciences (IPM)

The degree pattern of a finite group has been introduced in [18].A group M is called k-fold OD- characterizable if there exist exactly k non-isomorphic finite groups having the same order and degree pattern as M .In particular,a 1-fold OD-characterizable group is simply called *** is shown that the alternating groups A m and A m+1 ,for m = 27,35,51,57,65,77,87,93 and 95,are OD-characterizable,while their automorphism groups are 3-fold *** is also shown that the symmetric groups S m+2 ,for m = 7,13,19,23,31,37,43,47,53,61,67,73,79,83,89 and 97,are 3-fold *** this,the following theorem is *** m be a natural number such that m *** one of the following holds: (a) if m = 10,then the alternating groups A m are OD-characterizable,while the symmetric groups S m are OD- characterizable or 3-fold OD-characterizable;(b) the alternating group A 10 is 2-fold OD-characterizable;(c) the symmetric group S 10 is 8-fold *** theorem completes the study of OD-characterizability of the alternating and symmetric groups A m and S m of degree m 100.

关键词：定理推导对称群同构群外径自然数 S10 AM Sm

A New Quantum Gray-Scale Image Encoding Scheme

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Communications in Theoretical Physics 2018年第2期69卷 215-226页

作者： mosayeb naseri mona abdolmaleky fariborz parandin negin fatahi ahmed farouk reza nazari department of physics kermanshah branchislamic azad universityKermanshahIran department of electrical engineering college of engineeringkermanshah branchislamic azad universityKermanshahIran computer sciences department faculty of computers and informationmansoura universityMansoura UniversityEgypt department of it engineering college of engineeringkermanshah branchislamic azad universityKermanshahIran

In this paper, a new quantum images encoding scheme is proposed. The proposed scheme mainly consists of four different encoding algorithms. The idea behind of the scheme is a binary key generated randomly for each pixel of the original image. Afterwards, the employed encoding algorithm is selected corresponding to the qubit pair of the generated randomized binary key. The security analysis of the proposed scheme proved its enhancement through both randomization of the generated binary image key and altering the gray-scale value of the image pixels using the qubits of randomized binary key. The simulation of the proposed scheme assures that the final encoded image could not be recognized visually. Moreover, the histogram diagram of encoded image is flatter than the original one. The Shannon entropies of the final encoded images are significantly higher than the original one, which indicates that the attacker can not gain any information about the encoded images.

关键词：编码算法图象灰阶 qubit 二进制随机化安全分析钥匙

Overlapping gastroesophageal reflux disease and irritable bowel syndrome:Increased dysfunctional symptoms

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World Journal of Gastroenterology 2010年第10期16卷 1232-1238页

作者： Shadi Sadeghi Yarandi Siavosh Nasseri-moghaddam Pardis Mostajabi reza Malekzadeh Digestive disease research center Shariati HospitalTehran University of Medical Sciences

AIM:To investigate the association of gastroesophageal reflux disease (GERD) and irritable bowel syndrome (IBS) in Iranian patients and examine the prevalence of functional symptoms of the gastrointestinal tract in patients presenting with either IBS, GERD or ***: Six thousand four hundred and seventy six patients presented to the Gastro-intestinal (GI) clinic with symptoms of functional dysfunction of GI tract, 1419 patients (62.0% women, 38.0% men; mean age: 37.4±11.5 years) met Rome or Rome criteria(depending on the year of diagnosis)for IBS.2658 patients were diagnosed with GERD based on clinical presentation and endoscopic *** assessed other functional symptoms(epigastric pain,nausea,vomiting,belching,constipation and diarrhea)in patients suffering from GERD,IBS or ***: Among IBS subjects, 63.6% (69.0% women, 31.0% men; mean age: 36.4±10.3 years) also hadGERD, whereas 34.7% of the non-IBS patients had GERD [odds ratio (OR) =3.2, 95% confidence interval (CI): 2.9-3.7, P<0.0001]. Among patients with GERD, 33.9% of subjects met Rome criteria compared to 13.5% of non-GERD patients (OR=3.6, 95% CI: 3.1-4.3, P<0.0001). Prevalence of all functional symptoms was higher in overlapping GERD and IBS subjects, when compared with their prevalence in the IBS subjects without GERD or GERD only subjects (P<0.05).CONCLUSION: This finding shows that in overlapping GERD and IBS, other functional abnormalities of the GI tract are also highly prevalent, suggesting a common underlying dysfunction.

关键词： Gastro-esophageal reflux disease Irritable bowel syndrome Helicobacter pylori Gastro-intestinal dysfunction Endoscopy

Assessing the response of dryland barley yield to climate variability in semi-arid regions,Iran

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Journal of Arid Land 2021年第9期13卷 905-917页

作者： Mohammad KHEIRI Jafar KAMBOUZIA reza DEIHIMFARD Saghi M moghaddam Seyran ANVARI Department of Agroecology Environmental Sciences Research InstituteShahid Beheshti UniversityTehran ***Iran Faculty of Environmental Sciences Czech University of Life Sciences PraguePrague 16500Czech Republic

Precipitation and temperature are the most abiotic factors that greatly impact the yield of crop,particularly in ***,as the main cereal is predominantly cultivated in dryland and the livelihood of smallholders depends on the production of this crop,particularly in arid and semi-arid *** study aimed to investigate the response of the grain yield of dryland barley to temperature and precipitation variations at annual,seasonal and monthly scales in seven counties of East and West Azerbaijan provinces in northwestern Iran during *** index(HI)was calculated and its relationship with dryland barley yield was evaluated at annual and monthly *** results showed that the minimum,maximum and mean temperatures increased by 0.19℃/a,0.11℃/a and 0.10℃/a,respectively,while annual precipitation decreased by 0.80 mm/a during *** in study area has become drier by 0.22/a in annual HI during the study *** effects of increasing temperature on the grain yield of dryland barley were more severe than the positive effects of increasing ***,weather variations in April and May were related more to the grain yield of dryland barley than those in other *** grain yield of dryland barley was more drastically affected by the variation of annual minimum temperature comparing with other weather ***,our findings illustrated that the grain yield of dryland barley increased by 0.01 t/hm^(2) for each unit increase in annual HI during ***,any increase in the monthly HI led to crop yield improvement in the study area,particularly in the drier counties,i.e.,Myaneh,Tabriz and Khoy in Iran.

关键词： humidity index crop yield spatiotemporal variation temperature precipitation