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Geostatistical Assessment of the Spatial Distribution of Some Chemical Properties in Calcareous Soils

Journal of Integrative Agriculture 2012年第10期11卷 1729-1737页

作者： Asma Najafian Mahmood Dayani hamid reza Motaghian Habibolah Nadian Department of Soil Sciences College of Agriculture Shiraz University Shiraz *** 1ran Department of Soil Sciences Khouzestan Ramin University of Agriculture and Natural Resources Ahwaz *** Iran Department of Soil Science Faculty of Agriculture Shahrekord University Shahrekord *** Iran

Spatial patterns of soil fertility parameters and other extrinsic factors need to be identified to develop farming practices that match agricultural inputs with local crop needs. Little is known about the spatial structure of nutrition in Iran. The present study was conducted in a 132-ha field located in central Iran. Soil samples were collected at 0-30 cm depth and were then analyzed for total nitrogen （N）, available phosphorus （P）, available potassium （K）, available copper （Cu）, available zinc （Zn）, available iron （Fe） and available manganese （Mn）. The results showed that the contents of soil organic matter, Cu and Zn in Marvdasht＇s farms were low. The spatial distribution model and spatial dependence level for soil chemical properties varied in the field. N, K, carbonate calcium equivalent （CaCO3） and electrical conductivity （EC） data indicated the existence of moderate spatial dependence. The variograms for other variables revealed stronger spatial structure. The results showed a longer range value for available P （480 m）, followed by total N （429 m）. The value of other chemical properties values showed a shorter range （128 to 174 m）. Clear patchy distribution of N, P, K, Fe, Mn, Cu and Zn were found from their spatial distribution maps. This proved that sampling strategy for estimating variability should be adapted to the different soil chemical properties and field management. Therefore, the spatial variability of soil chemical properties with strong spatial dependence could be readily managed and a site-specific fertilization scheme for precision farming could be easily developed.

关键词： geostatistics kriging spatial variability precision farming

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Statistical functions used for spatial modelling due to assessment of landslide distribution and landscape-interaction factors in Iran

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Geoscience Frontiers 2020年第4期11卷 1257-1269页

作者： hamid reza Pourghasemi Narges Kariminejad Amiya Gayen Marko Komac Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran Gorgan University of Agricultural Sciences and Natural Resources Dept.of Watershed&Arid Zone ManagementGorganIran Department of Geography University of CalcuttaKolkataIndia Faculty of Civil and Geodetic Engineering University of LjubljanaSlovenia

Landslides influence the capacity for safe and sustainable development of mountainous *** study explores the spatial distribution of and the interactions between landslides that are mapped using global positioning system(GPS) and extensive field surveys in Mazandaran Province,***-pattern assessment is undertaken using several univariate summary statistical functions,including pair correlation,spherical-contact distribution,nearest-neighbor analysis,and O-ring analysis,as well as bivariate summary statistics,and a markcorrelation *** maximum entropy method was applied to prioritize the factors controlling the incidence of landslides and the landslides susceptibility *** validation processes were considered for separated 30%data applying the ROC curves,fourfold plot,and Cohen’s kappa *** results show that pair correlation and O-ring analyses satisfactorily predicted landslides at scales from 1 to 150 *** smaller scales,from 150 to 400 m,landslides were randomly *** nearest-neighbor distribution function show that the highest distance to the nearest landslide occurred in the 355 *** spherical-contact distribution revealed that the patterns were random up to a spatial scale of 80 *** bivariate correlation functions revealed that landslides were positively linked to several linear features(including faults,roads,and rivers) at all spatial *** mark-correlation function showed that aggregated fields of landslides were positively correlated with measures of land use,lithology,drainage density,plan curvature,and aspect,when the numbers of landslides in the groups were greater than the overall average *** results of analysis of factor importance have showed that elevation(topography map scale:1:25,000),distance to roads,and distance to rivers are the most important factors in the occurrence of *** susceptibility model of landslides indicates an excellent accuracy,i.e.,the AUC value of lands

关键词： Landslide Spatial point pattern Summary statistic GIS Iran

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COVID-19 international outbreak and the need for a suitable estimation model: A second-order polynomial equation with constant coefficients based on imported infected cases seems inadequate

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Asian Pacific Journal of Tropical Medicine 2020年第4期13卷 185-186页

作者： hamid reza Niazkar Majid Niazkar Student Research Committee Gonabad University of Medical SciencesGonabadIran Department of Civil and Environmental Engineering Shiraz UniversityShirazIran

COVID-19 due to infections with the 2019 novel coronavirus(SARS-CoV-2)was first reported in Wuhan,Hubei Province,China in December *** to 2 March 2020,it has already spread to more than 55 countries,infected more than 85000 individuals,and yielded to about 3000 death cases[1].Due to the vigorous outbreak of COVID-19,it has become a global *** management and controlling of this worldwide threat inevitably relies on the preparedness and precise risk assessment of the future,particularly in countries that new cases have been *** this regard,estimation of new probable confirmed and death cases in the near future is crucial to health care systems of each *** a result,some researches have been conducted to address this new concern[2-4].

关键词： estimation cases precise

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Modeling and Analysis of Mechanization Projects of Wheat Production by GERT Networks

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Agricultural Sciences in China 2010年第7期9卷 1078-1083页

作者： reza Abdi hamid reza Ghasemzadeh Shamsollah Abdollahpour Majid Sabzeparvar Adel Dabbag Mohamadi Nasab Faculty of Agriculture University of Tabriz Faculty of Industrial University of Science and Industry(Iran)

In crop production systems,all operations such as seed bed preparation,etc.,must be accomplished on time,if yield reduction and low quality product are to be *** all operations in mechanized cropping projects require precise scheduling,planning and *** basic approach in all scheduling techniques is to form a network of activities and events relationships that graphically portrays the sequential relations between the tasks in a *** a network would as a powerful tool available a farm manager to plan,schedule,monitor and control a *** GERT（Graphical Evaluation and Review Technique） networks have most of advantages associated with networks and available system analyst in exact evaluation of certain types of networks,in this research it was used and mechanized wheat production system was simulated,modeled and *** activities,events and path were *** showed that the network model was able to answer any statistic questions concerning with the *** models,particularly GERT networks are increasingly powerful tool for modeling,scheduling,planning,controlling,and analyzing of agricultural mechanization projects.

关键词： GERT networks mechanization project scheduling wheat

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Monitoring and evaluation of building ventilation system fans operation using performance curves

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Energy and Built Environment 2020年第3期1卷 307-318页

作者： Mahendra Singh Muhyiddine Jradi hamid reza Shaker Center for Energy Informatics University of Southern DenmarkCampusvej 555230Denmark

Ventilation fans are an important component of any mechanically ventilated *** fan performance could significantly affect the whole building performance *** are several issues such as dirty blades,mechanical wear,aging of fans could impact the fan’s *** present work,a novel,indirect and data-driven methodology is introduced to monitor the ventilation fan unit *** proposed method is able to perform continuous monitoring of ventilation fan unit in *** real-time performance of 3 Air handling unit(AHU)fans is examined in an academic *** fan performance is modeled with the help of manufacturer data and compared against the real-time *** data-driven models are developed and *** first model is used to compute expected total fan pressure at a given airflow rate while second is a Support Vector Regression(SVR)model,to predict the fan *** performance monitoring of the ventilation fan unit is determined in terms of expected and actual fan energy *** indicated a significant performance gap in three ventilation fan unit in a case building known as OU44,located in city Odense,*** advantage of this method comprises simplicity,no direct human intervention and scalability to the series of ventilation units.

关键词： Buildings Ventilation system Fan unit Performance curve Modeling Fan efficiency Energy consumption HVAC Performance testing Support vector regression(SVR) Polynomial regression

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Fractal Analysis of Rainfall-Induced Landslide and Debris Flow Spread Distribution in the Chenyulan Creek Basin, Taiwan

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Journal of Earth Science 2016年第1期27卷 151-159页

作者： Zon-Yee Yang hamid reza Pourghasemi Yen-Hung Lee Department of Civil Engineering Tamkang University Department of Natural Resources and Environmental Engineering College of Agriculture Shiraz University

The Chenyulan Stream in Central Taiwan follows the Chenyulan fault line which is a major boundary fault in Taiwan. In recent years, many destructive landslides have occurred in the Chenyulan Creek Basin after heavy rainfall accompanied by several strong typhoons. Three examples of landslide distributions in the Chenyulan Creek Basin, before and after 1996 and after 2004 are analyzed. The box dimension and two-point correlation dimension are employed to describe the landslide area size distribution and distance distribution between every two landslides, respectively. It is found that the number of landslides increased in this period. However, the average landslide area decreased. The correlation dimension gradually increased from 1.15 to 1.32 during this period（before and after 1996 and after 2004）. This implies that the landslide distribution in the Chenyulan Creek Basin has become diffuse and extensive. The box dimension value shows the degree of the landslide density occupied in a space. The box dimension also increased from 0.3 to 0.69 during this period. The increasing box dimension means that the landslide presented in this creek basin has gradually increased. This indicates that the slopes of this creek basin have become more unstable and susceptible.

关键词： landslide distribution box dimension two-point correlation dimension Taiwan.

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Zinc chloride catalyzed synthesis of 5-substituted 1H-tetrazoles under solvent free condition

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Chinese Chemical Letters 2009年第11期20卷 1311-1314页

作者： Shahnaz Rostamizadeh hamid Ghaieni reza Aryan Ali Amani Department of Chemistry Faculty of SciencesK.N.Toosi University of TechnologyP.O.Box:15875-4416TehranIran Faculty of Material and Chemical Engineering Malek Ashtar University of TechnologyTehranIran Department of Chemistry Faculty of SciencesK.N.Toosi University of Technology P.O.Box:15875-4416TehranIran

Zinc chloride is an efficient and safe catalyst in the [3 ＋ 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as： the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.

关键词： 5-Substituted ^1H-tetrazoles Zinc chloride Sodium azide Solvent free

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Silicon Affects Transcellular and Apoplastic Uptake of Some Nutrients in Plants

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Pedosphere 2015年第2期25卷 192-201页

作者： Pooyan MEHRABANJOUBANI Ahmad ABDOLZADEH hamid reza SADEGHIPOUR Mahnaz AGHDASI Department of Biology Faculty of ScienceGolestan University

The positive effects of silicon(Si) on growth of plants have been well documented;however,the impact of Si on plant nutrient uptake remains *** growth,nutrient content and uptake of wheat(Triticum aestivum L.),canola(Brassica napus L.) and cotton(Gossypium hirsutum L.) plants were evaluated with or without application of 1.5 mmol L^(-1) *** of Si increased dry weights by 8%,30%and 30%and relative growth rate(RGR) by 10%,13%and 17%in the cotton,canola and wheat plants,*** plant relative water content(RWC) was also increased,but the plant transpiration was decreased by Si *** uptake and content of Ca^(2+) were 19%and 21%lower in the cotton and wheat plants with Si than those without Si,respectively;however,Si application increased both K^+ and Fe uptake and contents in all plant *** application reduced B uptake and content only in cotton and increased P and Zn^(2+) contents in all three plant *** decrease in Ca^(2+) uptake by Si application was sustained even in the presence of metabolic inhibitors 2,4-dinitrophenol and sodium *** of Ca^(2+) by Si application was enhanced or did not change when plant shoots were saturated with water vapor or their roots were exposed to low ***,Si application increased the uptake of transcellularly transported elements like K^+,P,Zn^(2+) and *** contrast,Ca2+ uptake which occurred via both apoplastic and transcellular pathways was decreased by Si application,possibly through reduction of apoplastic *** efficient nutrient uptake might be another promoting effect of Si on plant growth.

关键词： element content metabolic inhibitors plant growth uptake pathways water content

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Nonlinear energy harvesting from vibratory disc-shaped piezoelectric laminates

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Theoretical & Applied Mechanics Letters 2020年第4期10卷 253-261页

作者： Abdolreza Pasharavesh reza Moheimani hamid Dalir School of Mechanical Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Mechanical and Energy Engineering Purdue School of Engineering and TechnologyIndianapolisIN 46202USA

Implementing resonators with geometrical nonlinearities in vibrational energy harvesting systems leads to considerable enhancement of their operational bandwidths. This advantage of nonlinear devices in comparison to their linear counterparts is much more obvious especially at small-scale where transition to nonlinear regime of vibration occurs at moderately small amplitudes of the base excitation. In this paper the nonlinear behavior of a disc-shaped piezoelectric laminated harvester considering midplane-stretching effect is investigated. Extended Hamilton’s principle is exploited to extract electromechanically coupled governing partial differential equations of the system. The equations are firstly order-reduced and then analytically solved implementing perturbation method of multiple scales. A nonlinear finite element method(FEM) simulation of the system is performed additionally for the purpose of verification which shows agreement with the analytical solution to a large extent. The frequency response of the output power at primary resonance of the harvester is calculated to investigate the effect of nonlinearity on the system performance. Effect of various parameters including mechanical quality factor, external load impedance and base excitation amplitude on the behavior of the system are studied. Findings indicate that in the nonlinear regime both output power and operational bandwidth of the harvester will be enhanced by increasing the mechanical quality factor which can be considered as a significant advantage in comparison to linear harvesters in which these two factors vary in opposite ways as quality factor is changed.

关键词： Nonlinear resonator Coupled electromechanical modeling Energy harvesting Piezoelectric laminate

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Organo-silane compounds in medium density fiberboard:physical and mechanical properties

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Journal of Forestry Research 2015年第2期26卷 495-500页

作者： hamid reza Taghiyari Ali Karimi Paridah Md.Tahir Wood Science & Technology Department Faculty of Civil EngineeringShahid Rajaee Teacher Training University Department of Wood and Paper Science & Technology Faculty of Natural ResourcesThe University of Tehran Laboratory of Biocomposite Technology Institute of Tropical Forestry & Forest Products (INTROP)University Putra Malaysia (UPM)

We studied the effects of nanoparticles of organo-silane（NOS） compounds in the size range of20–80 nm on physical and mechanical properties in medium density fiberboard,and used NOS at four consumption levels of 0,50,100,and 150 g kg-1dry wood *** of all treatments was kept constant at 0.67 g *** water-repellent property of organo-silane significantly reduced water absorption（WA） and thickness swelling but mechanical properties declined due to the reduced proportion of wood-fiber as organo-silane was added to the matrix：the compression ratio of MDF panels and the integrity among wood-fibers both declined,resulting in reduced mechanical *** recommend use of 50 g of NOS/kg wood-fiber to improve WA and thickness swelling while retaining acceptable mechanical properties.

关键词： Composite-board Medium-density fiberboard(MDF) Nanotechnology Physical and mechanical properties Water-repellant Organo-silane

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