检索结果-南通市图书馆

Sunflower petals:Some physical properties and modeling distribution of their number,dimensions,and mass

Information Processing in Agriculture 2018年第2期5卷 185-198页

作者： amir hossein Mirzabe Golam Reza Chegini Javad Khazaei Department of Mechanical Engineering of Biosystems Faculty of Agricultural Engineering and TechnologyCollege of Agriculture&Natural ResourcesUniversity of TehranTehranIran Department of Mechanical Engineering of Biosystems College of AboureihanUniversity of TehranTehranIran

Sunflower petal is one of the parts of the sunflower which has drawn attention and has several applications these *** applications justify getting information about physical properties,mechanical properties,drying trends,*** order to design new machines and use new methods to harvest or dry the sunflower *** three varieties of sunflower,picking force of petals was measured;number of petals of each head was counted;unit mass and 1000-unit mass of fresh petals were measured and length,width,and projected area of fresh petals were calculated based on image processing technique;frequency distributions of these parameters were modeled using statistical distribution models namely Gamma,Generalized Extreme Value(G.E.V),Lognormal,and *** of picking force showed that with increasing number of days after appearing the first petal on each head from 5 to 14 and decreasing loading rate from 150 gmin^-1 to 50 g min^-1 values of picking force were decreased for three varieties,but diameter of sunflower head had different effects on picking force for each ***,width,and number of petals of Dorsefid variety ranged from 38.52 to 95.44 mm,3.80 to 9.28mm and 29 to 89,*** corresponding values ranged from 34.19 to 88.18 mm,4.28 to 10.60 mm and 21 to 89,respectively for Shamshiri variety and ranged from 44.47 to 114.63 mm,7.03 to 20.31 mm and 29 to 89 for Sirena *** of frequency distribution modeling indicated that in most cases,G.E.V and Weibull distributions had better performance than other distributions.

关键词： Sunflower(Helianthus annus L.)petal Picking force Image processing Fibonacci sequence Lucas sequence

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Preservation of organic matter in soils of a climobiosequence in the Main Range of Peninsular Malaysia

引用

Journal of Mountain Science 2017年第9期14卷 1763-1775页

作者： amir hossein JAFARZADEH-HAGHIGHI Jusop SHAMSHUDDIN Jol HAMDAN Norhazlin ZAINUDDIN Department of Land Management Faculty of Agriculture Universili Putra Malaysia 43400 Serdang Selangor Malaysia Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 Serdang Selangor Malaysia

Limited information is available about factors of soil organic carbon(SOC) preservation in soils along a climo-biosequence. The objective of this study was to evaluate the role of soil texture and mineralogy on preservation of SOC in the topsoil and subsoil along a climo-biosequence in the Main Range of Peninsular Malaysia. Soil samples from the A and B-horizons of four representative soil profiles were subjected to particle-size fractionation and mineralogical analyses including X-ray diffraction and selective dissolution. The proportion of SOC in the 250-2000 μm fraction(SOC associated with coarse sand) decreased while the proportion of SOC in the <53 μm fraction(SOC associated with clay and silt)increased with depth. This reflected the importance of the fine mineral fractions of the soil matrix for SOC storage in the subsoil. Close relationships between the content of SOC in the <53 μm fraction and the content of poorly crystalline Fe oxides [oxalate-extractable Fe(Fe_o) – pyrophosphate-extractable Fe(Fe_p)] and poorly crystalline inorganic forms of Al [oxalateextractable Al(Al_o) – pyrophosphate-extractable Al(Al_p)] in the B-horizon indicated the importance of poorly crystalline Fe oxides and poorly crystalline aluminosilicates for the preservation of SOC in the Bhorizon. The increasing trend of Fe_o-Fe_p and Al_o-Al_p over elevation suggest that the importance of poorly crystalline Fe oxides and poorly crystalline aluminosilicates for the preservation of SOC in the Bhorizon increased with increasing elevation. This study demonstrates that regardless of differences in climate and vegetation along the studied climobiosequence, preservation of SOC in the subsoil depends on clay mineralogy.

关键词： Particle-size fractionation Poorly crystalline minerals Soil organic matter Soil texture

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluation of suspended load transport rate using transport formulas and arti- ficial neural network models (Case study: Chelchay Catchment)

引用

Journal of Hydrodynamics 2013年第3期25卷 459-470页

作者： HADDADCHI Arman MOVAHEDI Neshat VAHIDI Elham OMID Mohammad hossein DEHGHANI amir Ahmad Australian Rivers Institute Griffith University Nathan QLD 4111 Australia Department of Water Engineering Gorgan University of Agricultural Sciences and Natural Resources GorganIran Department of Irrigation and Reclamation Engineering University of Tehran Karaj Iran

Accurate estimation of sediment load or transport rate is very important to a wide range of water resources projects. This study was undertaken to determine the most appropriate model to predict suspended load in the Chelehay Watershed, northeast of Iran. In total, 59 data series were collected from four gravel bed-rivers and a sand bed river and two depth integrating suspended load samplers to evaluate nine suspended load formulas and feed forward backpropagation Artificial Neural Network （ANN） structures. Although the Chang formula with higher correlation coefficient （r = 0.69） and lower Root Mean Square Error （RMSE = 0.013） is the best suspended load predictor among the nine studied formulas, the ANN models significantly outperform traditional suspended load formulas and show their superior performance for all statistical parameters. Among different ANN structures two models inclu- ding 4 inputs, 4 hidden and one output neurons, and 4 inputs, 4 and one hidden and one output neurons provide the best simulation with the RMSE values of 0.0009 and 0.001, respectively.

关键词： sediment transport suspended load formulas Artificial Neural Network (ANN) river engineering

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A review of the mechanical integrity and electrochemical performance of flexible lithium-ion batteries

引用

Nano Research 2023年第12期16卷 12962-12982页

作者： Ahmad Shokrieh amir hossein Mirzaei Lijuan Mao Mahmood M.Shokrieh Zhixiang Wei CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China Composites Research Laboratory Center of Excellence in Experimental Solid Mechanics and DynamicsSchool of Mechanical EngineeringIran University of Science and TechnologyTehran 16846-13114Iran University of Chinese Academy of Sciences Beijing 100049China

In the past two decades,various research works have been conducted in the field of flexible electronic devices(FEDs).Researchers have focused their efforts on solving the existing challenges in the electronic,electrochemical,and mechanical behaviors of *** importance of flexible lithium-ion batteries(FLIBs)in the area of FEDs is evident;however,less attention has been paid to the mechanical behavior of FLIBs in comparison with the material and electrochemical *** present paper reviewed the research works in the FLIBs,focusing on their mechanical integrity and electrochemical ***,an introduction to FLIBs was presented,and the previous review papers published in this field were briefly ***,a detailed review of the available electrochemical and mechanical research works on FLIBs was ***,the mechanical testing methods(tensile,compressive,indentation,fatigue,and adhesion)for the characterization of FLIBs’components,the research works on the simulation and modeling of the mechanical behavior of FLIBs,and a summary of the present situation and the future trend of research in this field were reviewed and presented.

关键词： flexible devices electrochemical performance mechanical integrity testing methods simulation and modeling.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comprehensive power swing detection by current signal modeling and prediction using the GMDH method

引用

Protection and Control of Modern Power Systems 2021年第1期6卷 204-214页

作者： Seyed amir hosseini Behrooz Taheri hossein Askarian Abyaneh Farzad Razavi Department of Electrical Engineering Golpayegan University of TechnologyIsfahanIran Faculty of Electrical Biomedical and Mechatronics EngineeringQazvin BranchIslamic Azad UniversityQazvinIran Department of Electrical Engineering Amirkabir University of TechnologyTehranIran

Power swing is an undesirable variation in power flow. This can be caused by large disturbances in demand load, switching, disconnection or reclosing lines. This phenomenon may enter the zones of distance relays and cause relay malfunction leading to the disconnection of healthy lines and undermining network reliability. Accordingly, this paper presents a new power swing detection method based on the prediction of current signal with a GMDH (Group Method of Data Handling) artificial neural network. The main advantage of the proposed method over its counterparts is the immunity to noise effect in signals. In addition, the proposed method can detect stable, unstable, and multi-mode power swings and is capable of distinguishing them from the variety of permanent faults occurring simultaneously. The method is tested for different types of power swings and simultaneous faults using DIgSILENT and MATLAB, and compared with some latest power swing detection methods. The results demonstrate the superiority of the proposed method in terms of response time, the ability to detect power swings of different varieties, and the ability to detect different faults that may occur simultaneously with power swings.

关键词： Power swing Distance relay Power system protection GMDH

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A low-voltage and energy-efficient full adder cell based on carbon nanotube technology

引用

Nano-Micro Letters 2010年第2期2卷 114-120页

作者： Keivan Navi Rabe'e Sharifi Rad Mohammad hossein Moaiyeri amir Momeni Faculty of Electrical and Computer Engineering Shahid Beheshti UniversityGC

Scaling problems and limitations of conventional silicon transistors have led the designers to exploit novel nano-technologies. One of the most promising and feasible nano-technologies is CNT(Carbon Nanotube) based transistors. In this paper, a high-speed and energy-efficient CNFET(Carbon Nanotube Field Effect Transistor) based Full Adder cell is proposed for nanotechnology. This design is simulated in various supply voltages, frequencies and load capacitors using HSPICE circuit simulator. Significant improvement is achieved in terms of speed and PDP(Power-Delay-Product) in comparison with other classical and state-of-the-art CMOS and CNFET-based designs, existing in the literature. The proposed Full Adder can also drive large load capacitance and works properly in low supply voltages.

关键词： CNFET Low-Voltage Full-Adder Minority-Function Nanotechnology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Investigation of production depletion rate effect on the ne ar-wellbore stresses in the two Iranian southwest oilfields|

引用

Petroleum Research 2020年第4期5卷 347-361页

作者： Khalil Shahbazi amir hossein Zarei Alireza Shahbazi Abbas Ayatizadeh Tanha Faculy Member of Petroleur University of Technologx Iran Ahwaz Faculy of Engineering Petroleurm University of Techunology Iran National lrunion Driling Compury Well Logging DepartmentAhwazlran

Effect of depletion rate on wellbore stability due to production of oil from hydrocarbon-bearing reser-voirs is important and can result in a reduction of the reservoir pore pressure.A reduction in the reservoir pressure,in tum,results in a change in the stresses acting within the *** these changes are not well analyzed and applied in future calculations,we may be unsuccessful in some cases such as drilling infill wells or extended wells,forecast of sand production and optimum flow rate,preventing of casing collapse,***,knowing the stresses around the well at every stage of production is fundamental to the next *** this paper,we recognized these changes in near-wellbore stresses using data from logging(image log,dipole sonic,full set log,mud log),production data,infor-mation from kick,blow out,loss *** determined it using Techlog software and theoretical *** wells of two huge oilfields of sw Iran were investigated after depletion or production for long *** each well,state of stresses were calculated in cases of safe drilling mud weight using log data and theoretical *** the end effect of depletion rate on wellbore stability was investigated in these three wells.

关键词： Depletion rate Wellbore stability Pore pressure Sand production Near-wellbore stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effects of hooked-collar on the local scour around a lenticular bridge pier

引用

International Journal of Sediment Research 2023年第1期38卷 1-11页

作者： Rashid Farooq amir hossein Azimi Muhammad Atiq Ur Rehman Tariq Afzal Ahmed Department of Civil Engineering International Islamic University Department of Civil Engineering Lakehead University College of Engineering and Science Victoria University Department of Civil Engineering University of Engineering and Technology James Watt School of Engineering University of Glasgow

This paper presents the results of comprehensive laboratory experiments to investigate the effects of hooked-collar on the scour development around a vertical pier with a lenticular cross section. The flow around the pier was uniform, steady, and under the clear-water condition. The axial scour profiles for cases without and with a lenticular hooked-collar were measured and the effects of hooked-collar dimensions and elevation from the bed were examined. To compute the efficiency of hooked-collar for scour prevention, the results of local scour for a bridge pier without a collar and a bridge pier with a plain collar, without a hooked wall, were used as benchmark data sets. A wide range of hooked-collar geometries such as the ratio of collar width to the pier width, Wc/Wp, ranging from 1.5 to 3.5, the ratio of hooked-collar wall height to the pier width, Hc/Wp, ranging from 0.15 to 0.6, and the ratio of collar elevation to the pier width, Ec/Wp, of-0.5, 0, and 0.5 were tested. The experimental results indicated that the equilibrium scour depth decreased with the ratio of hooked-collar to the pier width when Wcis twice the pier width, Wp. For Wc/Wp> 2, the scour depth was similar to the tests with an infinitely large pier width. In addition, the scour depth consistently reduced as the hooked-collar wall height, Hc, to the pier width, Wp, approached 0.3. The highest scour reduction efficiency was achieved when the hooked-collar being placed on the bed surface. Empirical models were developed for prediction of maximum scour depth near the lenticular bridge pier with a modified collar. The results showed that the volume of scour hole around a lenticular pier increased non-linearly with the maximum scour depth and it was independent of the hooked-collar geometry.

关键词： Local scour Erosion Collar Hooked-collar Lenticular pier Scour countermeasure Steady flow

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Adaptive Fuzzy Sliding Mode Control of Under-actuated Nonlinear Systems

引用

International Journal of Automation and computing 2018年第3期15卷 364-376页

作者： amir hossein Davaie Markazi Mohammad Maadani Seyed Hassan Zabihifar Nafiseh Doost-Mohammadi School of Mechanical Engineering Iran University of Science and Technology

A new extension of the conventional adaptive fuzzy sliding mode control（AFSMC） scheme, for the case of under-actuated and uncertain affine multiple-input multiple-output（MIMO） systems, is presented. In particular, the assumption for non-zero diagonal entries of the input gain matrix of the plant is relaxed. In other words, the control effect of one actuator can propagate from a subgroup of canonical state equations to the rest of equations in an indirect sense. The asymptotic stability of the proposed AFSM control method is proved using a Lyapunov-based methodology. The effectiveness of the proposed method for the case of under-actuated systems is investigated in the presence of plant uncertainties and disturbances, through simulation studies.

关键词： Adaptive fuzzy sliding mode control (AFSMC) nonlinear systems uncertain systems under-actuated systems remoteenvironmental monitoring units (REMUS).

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluation of some engineering properties of cucumber(Cucumis sativus L.)seeds and kernels based on image processing

引用

Information Processing in Agriculture 2017年第4期4卷 300-315页

作者： amir hossein Mirzabe Masoud Barati kakolaki Behnam Abouali Rasoul Sadin Department of Mechanical Engineering of Biosystems Aboureihan CollegeTehran UniversityTehranIran Department of Biosystems Bajgah CollegeShiraz UniversityShirazIran

In this study,a method based on digital image processing was employed to investigate effect of the moisture content on gravimetrical and frictional properties of the cucumber seeds and *** research indicated that the application of visual machines and the image processing could be a rapid method that enables accurate measurement of the dimensional parameters of two varieties of this product *** length,width,and thickness of the seeds of Rashid variety ranged from 6.40 to 9.07,2.91 to 4.21 and 0.65 to1.50 mm,respectively;the corresponding value of Negin variety ranged from 6.89 to 9.07,2.49 to 4.21,and 0.69 to 1.68 mm,*** and shell ratios of the Rashid variety were found to be 69.811 and 30.189%,respectively;the corresponding values of the Negin variety were found to be 72.727 and 27.273%,*** the bulk densities of the two varieties of cucumber seeds and kernels that decreased with the moisture content,true density and porosity of the two varieties of cucumber seeds and kernels *** the moisture content increased from 5.04 to 21.12%(d.b),the angle of the static friction of the seeds of Negin variety increased from 30.39°to 37.18°,28.83° to 34.991,24.37°to 30.04°,and 15.77°to 19.57°for wood,rubber,iron,and galvanized,respectively,the corresponding value of the Negin variety increased from 21.12to 27.16°,24.43°to 31.41°,19.90°to 25.59°and 14.09°to 18.12°as the moisture content increased from 5.02 to 21.02%(d.b).

关键词： Image processing Physical and mechanical properties Cucumber

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：