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Hybrid global gridded snow products and conceptual simulations of distributed snow budget:evaluation of different scenarios in a mountainous watershed

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Frontiers of Earth Science 2023年第2期17卷 391-406页

作者： Mercedeh TAHERI Milad Shamsi ANBOOHI Rahimeh MOUSAVI mohsen nasseri School of Civil Engineering College of EngineeringUniversity of TehranTehran ***Iran Department of Civil Engineering University of OttawaOttawaOntario K1N6N5Canada Department of Civil Engineering Faculty of EngineeringUniversity of ZanjanZanjan 45371-38791Iran

Considering snowmelt in mountainous areas as the important source of streamflow,the snow accumulation/melting processes are vital for accurate simulation of the hydrological *** lack of snow-related data and its uncertainties/conceptual ambiguity in snowpack modeling are the different challenges of developing hydroclimatological *** tackle these challenges,Global Gridded Snow Products(GGSPs)are introduced,which effectively simplify the identification of the spatial characteristics of snow hydrological *** research aims to investigate the performance of multisource GGSPs using multi-stage calibration strategies in hydrological *** used GGSPs were Snow-Covered Area(SCA)and Snow Water Equivalent(SWE),implemented individually or jointly to calibrate an appropriate water balance *** study area was a mountainous watershed located in Western Iran with a considerable contribution of snowmelt to the generated *** results showed that using GGSPs as complementary information in the calibration process,besides streamflow time series,could improve the modeling accuracy compared to the conventional calibration,which is only based on streamflow *** SCA with NSE,KGE,and RMSE values varying within the ranges of 0.47–0.57,0.54–0.65,and 4–6.88,respectively,outperformed the SWE with the corresponding metrics of 0.36–0.59,0.47–0.60,and 5.22–7.46,respectively,in simulating the total streamflow of the *** addition to the superiority of the SCA over SWE,the twostage calibration strategy reduced the number of optimized parameters in each stage and the dependency of internal processes on the streamflow and improved the accuracy of the results compared with the conventional calibration *** the other hand,the consistent contribution of snowmelt to the total generated streamflow(ranging from 0.9 to 1.47)and the ratio of snow melting to snowfall(ranging from 0.925 to 1.041)in different calibration strategies and models resu

关键词： global gridded snow products snow hydrology multi-stage calibration strategy hydroclimatological modeling mountainous watershed

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Parallel boron nitride nanoribbons and etch tracks formed through catalytic etching

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Nano Research 2018年第9期11卷 4874-4882页

作者： Armin Ansary mohsen nasseri Mathias J. Boland Douglas R. Strachan Department of Physics &Astronomy University of Kentucky Lexington KY40506 USA

One-dimensional （1D） catalytic etching was investigated in few-layer hexagonal boron nitride （hBN） films. Etching of hBN was shown to share a number of similarities with that of graphitic films. As in graphitic films, etch tracks in hBN commenced at film edges and occurred predominantly along certain crystal directions of its lattice, though it was shown that the tracks were generally narrower than those of few-layer graphene under similar processing conditions. It was also shown that catalytic hydrogenation can occur completely through a few-layer hBN film, demonstrating that this process can be used in the formation of isolated low-dimensional nanoscale structures from other layered 2D materials beyond graphene. This ability for thin hBN films to be etched completely through allowed for a crystalline substrate to guide the etching process, which was demonstrated with the successful etch track formation of few-layer hBN on single-crystalline sapphire substrates. The substrate-guided etching resulted in parallel few-layer hBN nanoribbons having an average width of 32 nm and spacing of 13 nm.

关键词： hexagonal(hBN) one-dimensional catalytic etching hydrogenation etch tracks nanoribbons

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Evaluation of Stiffened End-Plate Moment Connection through Optimized Artificial Neural Network

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Journal of Software Engineering and Applications 2012年第3期5卷 156-167页

作者： Mehdi Ghassemieh mohsen nasseri School of Civil Engineering University of Tehran Tehran Iran

This study involves the development of an analytical model for understanding the behavior of the extended, stiffened end-plate moment connections with eight high strength bolts. Modeling of the connection as an assemblage of finite elements (FE) used for load deformation analysis, with material, and contact nonlinearities are developed. Results from the FE mathematical model are verified with results from the ANSYS computer program as well as with the test results. Sensitivity and feasibility studies are carried out. Significant geometry and force related variables are introduced;and by varying the geometric variables of the connections within a practical range, a matrix of test cases is obtained. Maximum end-plate separation, maximum bending stresses in the end-plate, and the forces from the connection bolts for these test cases are obtained. From the FE analysis, a database is produced to collect results for the artificial neural network analysis. Finally, salient features of the optimized Artificial Neural Network (ANN) via Genetic Algorithm (GA) analysis are introduced and implemented with the aim of predicting the overall behavior of the connection.

关键词： End-Plate Moment Connection Finite Element Method Artificial Neural Network Sensitivities Analysis Genetic Algorithm

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Droughts and the Impacts of Dry Spells in North of Iraq

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Research in Ecology 2021年第1期3卷 59-69页

作者： Safieh Javadinejad David Hannah Stefan Krause Rebwar Dara Forough Jafary mohsen nasseri University of Birmingham BirminghamUK University of knowledge ErbilIraq University of Tehran TehranIran

Different sets of dry spell length such as complete series, monthlymaximum, seasonal maximum, and annual maximum are applied andmodeled with different probability distribution functions (such as GumbelMax, generalized extreme value, Log-Logistic, generalized logistic, inverseGaussian, Log-Pearson 3, generalized Pareto) to recognize in whichduration, dry spells cause drought. The drought situation and temporalanalysis in the North of Iraq region were done using the SPI index andby software of DrinC at a time scale of 3.6 and 12 months. Because ofapplicability, availability of data and the aim of the study, SPI is selectedto analyze the dry spells in this study. Based on the maximum length ofthe available statistical period, the statistics for the years 1980 to 2019were used from nine meteorological stations for analysis. The results of thestudy showed the severity of drought during the study period which relatedto dry spells. The results of this research confirm the variation of droughtoccurrence with varying degrees in different time and different dry spellscondition in Iraq.

关键词： Dry spells Drought Climate change Indices

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Evaluation of Stiffened End-Plate Moment Connection through Optimized Artificial Neural Network

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Journal of Software Engineering and Applications（软件工程与应用） 2012年第3期

作者： Mehdi Ghassemieh mohsen nasseri

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The behavior of HfB_2 under neutron irradiation

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Nuclear Science and Techniques 2016年第2期27卷 14-17页

作者： Mohammad Mehdi nasseri School of Plasma Physics and Nuclear Fusion Institute of Nuclear Science and Technology (AEOI)

Due to the interesting properties of hafnium diboride(HfB_2) as a ceramic, it has drawn considerabl attention from several researchers. To understand th radiation properties of HfB_2 that may be used in the nuclea industry, the interaction of this composite under neutro irradiation was studied. It is obvious that, because HfB_2 ha Boron, this composite has the potential to absorb neutron particularly in the range of thermal energy. The ^(10)B(n, a7 Li interaction is dominant among other interactions tha produce alpha particles. The results revealed that alph particles have a high fluctuation diagram following a saw tooth spectrum for thermal neutron energy, which has to b carefully analyzed. If HfB_2 is intended to be used in fusio facilities, for example in fusion reactors, its interactio with high neutrons(14 Me V) should be studied. Th results of this case showed that, in the wide range of alph energy, the amount of alpha particles is almost constant, s this continuum spectrum is almost flat and there is just small peak at 2.31 Me V that belongs to the very famou interaction [^(10)B(n, a)~7Li].

关键词：中子辐照相互作用行为能量范围复合材料聚变反应堆 α粒子研究人员

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Monte-Carlo simulation for determining SNR and DQE of linear array plastic scintillating fiber

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Nuclear Science and Techniques 2004年第5期15卷 304-307页

作者： Mohammad Mehdi nasseri Department of Modern Physics University of Science and Technology of China Hefei 230026

Fundamental characteristics of the plastic-scintillating fiber (PSF) for wide energy range of electromag- netic radiation (X & γ) have been studied to evaluate possibility of using the PSF as an imaging detector for industrial purposes. Monte-Carlo simulation program (GEANT4.5.1, 2003) was used to generate the data. In order to evaluate image quality of the detector, fiber array was irradiated under various energy and fluxes. Signal to noise ratio (SNR) as well as detector quantum efficiency (DQE) were obtained.

关键词： Monte-Carlo GEANT4 SNR

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Image quality evaluation of linear plastic scintillating fiber array detector for X-ray imaging

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Nuclear Science and Techniques 2004年第6期15卷 361-364页

作者： Mohammad Mehdi nasseri Department of Modern Physics University of Science and Technology of China Hefei 230026

It is important to assess image quality, in order to ensure that the imaging system is performing optimally and also identify the weak points in an imaging system. Three parameters mostly leading to image degradation are contrast, spatial resolution and noise. There is always a trade-off between spatial resolution and signal to noise ratio, but in scintillating fiber array detectors spatial resolution is not as important as signal to noise ratio, so we paid more attention to contrast and SNR of the system. By using GEANT4 Monte Carlo detector simulation toolkit, some effec- tive parameters of the linear plastic scintillating fiber (PSF) array as an imaging detector were investigated. Finally we show that it is possible to use this kind of detector to take CT and DR (Digital Radiography) image under certain conditions.

关键词：闪烁纤维 X射线调制变换函数 GEANT4 图象质量

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Comparative efficacy of honey 12.5% and chlorhexidine 0.2% mouthwashes on the oropharyngeal bacterial colonization in mechanically-ventilated patients: a randomized controlled trial

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Journal of Traditional Chinese Medicine 2020年第3期40卷 440-446页

作者： Halimeh Amiri Farhad Ramezani-Badr Naseh Sigari Karim nasseri Department of Critical Care Nursing School of Nursing and MidwiferyZanjan University of Medical SciencesZanjan ***Iran Department of Intrenal Medicine Kurdistan University of Medical SciencesSanandaj ***Iran Department of Anesthesiology Faculty of MedicineKurdistan University of Medical SciencesSanandaj ***Iran

OBJECTIVE: To compare the efficacy of honey mouthwash 12.5% and chlorhexidine solution 0.2%to reduce the rate of oropharyngeal bacterial colonization in mechanically-ventilated ***: This study was a randomized, single blind, phase Ⅲ controlled clinical trial. Sixty patients newly admitted to internal and trauma Intensive Care Units of the two educational hospitals of Sanandaj city affiliated with Kurdistan University of Medical Sciences were selected by convenience sampling and allocated to two groups of 30 patients using random blocks design. In each group,the mouthwash was applied twice a day for four consecutive days. Swab samples were taken from the mouth and throat of all patients three times a day(pre-intervention, two days, and four days after the intervention) and then the samples were transferred onto the blood agar and eosin methylene blue(EMB) culture plates and investigated for bacterial growth and colonization after 24-48 ***: The findings showed that oropharyngeal colonization was not significantly different between the two groups, pre-intervention, two days,and four days after the intervention(P > 0.05). Rinsing with honey mouthwash 12.5% led to the inhibition of Staphylococcus aureus and Pseudomonas aeruginosa on the fourth day of the intervention in all ***: None of the studied solutions contributed to the reduction of oropharyngeal bacterial colonization. It seems that the growth inhibition of Staphylococcus aureus and Pseudomonas aeruginosa by the honey 12.5% mouthwash in mechanically-ventilated patients need further investigation.

关键词： Mouthwashes Honey Chlorhexidine Ventilators mechanical Oropharyngeal colonization Intensive Care Unit Randomized controlled trial

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原位应力下裂缝性致密砂岩各向异性地震波速及其渗透率关联特征

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煤炭学报 2022年第1期47卷 246-258页

作者： XIA Kaiwen 李星齐春艳姚伟肖香姣张杰 nasseri M H B 天津大学水利仿真与安全国家重点实验室天津300072 多伦多大学土木与矿业工程学院加拿大多伦多M5S1A4 中国石油集团工程技术研究院有限公司北京102206 中国石油塔里木油田公司新疆库尔勒841000

超深层裂缝性非常规天然气藏的开发在能源领域所占比重越来越大,但目前关于该类型储层在原位应力下各向异性地震波速及渗透率的基础研究仍鲜有报道,一定程度上制约了其高效开发策略的制定进程。以塔里木油田克深2号裂缝性致密砂岩天然... 详细信息

超深层裂缝性非常规天然气藏的开发在能源领域所占比重越来越大,但目前关于该类型储层在原位应力下各向异性地震波速及渗透率的基础研究仍鲜有报道,一定程度上制约了其高效开发策略的制定进程。以塔里木油田克深2号裂缝性致密砂岩天然气储层为工程背景,利用先进的地球物理成像真三轴测试系统,开展了储层衰竭期间原位应力下完整砂岩与不同倾角裂缝岩样的各向异性地震波速以及各向异性渗透率演化规律实验研究,探讨了压缩波、剪切波、纵横波速比、3个主应力方向渗透率各向异性特性与内在机制,研究了地震波速与渗透率的内在关联特征。研究结果表明:首先,裂缝引起的结构非均质性以及三向不等应力作用下岩石各主应力方向微观结构的变形差异导致了地震波速的各向异性;储层衰竭期间地震波速度均随有效应力的增大近似线性增加,压缩波速度明显大于剪切波速度;纵横波速比随有效应力增大而单调减小,表明剪切波对外部荷载敏感性更强;通过压缩波速和纵横波波速比数据对比,发现剪切波S2速度对裂缝倾角更为敏感。其次,原位应力下各主方向渗透率均表现出显著的应力敏感性和结构(裂缝)敏感性,早期应力大小对储层衰竭中后期渗透率变化具有重要影响,渗透率各向异性随裂缝倾角减小而更加显著;与裂缝平面正(斜)交方向的渗透率相对比较平滑,而沿裂缝平面方向渗透率呈现出一定的波动特性,这主要是由于在压力流体冲刷和岩石骨架进一步受压变形双重作用下,破碎的微颗粒会在孔隙/裂隙中不断运移,造成岩石内部孔隙/裂隙周期性堵塞和疏通引起的。此外,在实验应力条件下(走滑应力状态),裂缝倾角越小,水平主应力方向上的地震波速度-渗透率相关性越不明显;最大与最小水平主应力方向上的地震波速度-渗透率关系应区分对待,最大水平主应力方向地震波速与渗透率的相关性明显优于最小水平主应力方向。

关键词：真三轴应力裂缝砂岩地震波速渗透率各向异性

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