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

Experimental Evaluation of a Multistage Reciprocating Evaporative Cooler Performance for Varied Climatic Conditions

引用

Journal of Thermal Science 2023年第4期32卷 1523-1535页

作者： Sampath SURANJAN SALINS S.V.KOTA REDDY Shiva KUMAR School of engineering and IT Manipal Academy of Higher EducationDubai CampusDubaiPO 345050UAE mechanical engineering department VIT-AP UniversityAmaravatiAndra Pradesh52223India department of mechanical and Manufacturing engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipal576104India

Current system focuses on design&construction of a multistage reciprocating evaporative cooling test *** packings that are used will undergo the reciprocating action,powered by the cam follower mechanism maintained at an actual rotation *** dry bulb temperature&humidity values are varied to replicate the varying climatic conditions,and the output parameters such as cooling load,evaporation rate(ER),humidification efficiency(HE),coefficient of performance(COP)are *** results showed that as inlet humidity raises,the performance of system *** the rise in the camshaft speed or packing velocity,there is an upsurge in the performance until a cam speed of 10 r/min or packing velocity of 0.083 m/s and with further increases in the value,overall performance *** system gave a maximum COP,ER,and HE equal to 3.80,73.87%,and 0.53 g/kg respectively.A rise in the inlet air temperature yielded a maximum change in dry bulb temperature of 8.2℃.Overall,results indicated that evaporative cooling is more effective in arid climates than the cold and humid *** quality test is performed to measure CO_(2),Total Volatile Organic Compound(TVOC),and Formaldehyde(HCHO),and it is found that humidified air entering the defined space is of excellent quality.

关键词： multistage humidifier evaporative cooling reciprocating packing humidification efficiency

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

RANDOM VARIABLE WITH FUZZY PROBABILITY

引用

Applied Mathematics and Mechanics(English Edition) 2003年第4期24卷 491-498页

作者：吕恩琳钟佑明 department of engineering Mechanics Chongqing University College of mechanical engineering Chongqing University

Mathematic description about the second kind fuzzy random variable namely the random variable with crisp event-fuzzy probability was studied. Based on the interval probability and using the fuzzy resolution theorem, the feasible condition about a probability fuzzy number set was given,go a step further the definition and characters of random variable with fuzzy probability (RVFP) and the fuzzy distribution function and fuzzy probability distribution sequence of the RVFP were put forward. The fuzzy probability resolution theorem with the closing operation of fuzzy probability was given and proved. The definition and characters of mathematical expectation and variance of the RVFP were studied also. All mathematic description about the RVFP has the closing operation for fuzzy probability,as a result, the foundation of perfecting fuzzy probability operation method is laid.

关键词： random variable fuzzy probability probability mathematical expectation variance

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 critical review of the integration of renewable energy sources with various technologies

引用

Protection and Control of Modern Power Systems 2021年第1期6卷 37-54页

作者： Erdiwansyah Mahidin H.Husin Nasaruddin M.Zaki Muhibbuddin Doctoral Program School of EngineeringUniversitas Syiah KualaBanda Aceh23111Indonesia Faculty of engineering Universitas Serambi MekkahBanda Aceh23245Indonesia department of Chemical engineering Universitas Syiah KualaBanda Aceh23111Indonesia department of Electrical and Computer engineering Universitas Syiah KualaBanda Aceh23111Indonesia department of mechanical and industrial engineering Universitas Syiah KualaBanda Aceh23111Indonesia

Wind power, solar power and water power are technologies that can be used as the main sources of renewable energy so that the target of decarbonisation in the energy sector can be achieved. However, when compared with conventional power plants, they have a significant difference. The share of renewable energy has made a difference and posed various challenges, especially in the power generation system. The reliability of the power system can achieve the decarbonization target but this objective often collides with several challenges and failures, such that they make achievement of the target very vulnerable, Even so, the challenges and technological solutions are still very rarely discussed in the literature. This study carried out specific investigations on various technological solutions and challenges, especially in the power system domain. The results of the review of the solution matrix and the interrelated technological challenges are the most important parts to be developed in the future. Developing a matrix with various renewable technology solutions can help solve RE challenges. The potential of the developed technological solutions is expected to be able to help and prioritize them especially cost-effective energy. In addition, technology solutions that are identified in groups can help reduce certain challenges. The categories developed in this study are used to assist in determining the specific needs and increasing transparency of the renewable energy integration process in the future.

关键词： Integration RE Energy source Technology system energy Power system Variable RE

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

Thermally stable ultrafine grained copper induced by CrB/CrB_(2) microparticles with surface nanofeatures via regular casting

引用

Journal of Materials Science & Technology 2020年第23期58卷 55-62页

作者： Gongcheng Yao Chezheng Cao Shuaihang Pan Jie Yuan Igor De Rosa Xiaochun Li department of Materials Science and engineering University of CaliforniaLos AngelesCA 90095USA department of mechanical and Aerospace engineering University of CaliforniaLos AngelesCA 90095USA

Ultrafine-grained(UFG)/nanocrystalline materials possess novel properties. Refining as-solidified grains of metals to the ultrafine and even nanometer scale by nanoparticles via slow cooling has been recently discovered. Here, we report that microparticles(CrB and CrB_(2)) with surface nanofeatures can also enable ultrafine/nano grains via slow cooling. CrB/CrB_(2) microparticles, formed by coalescence of nanoparticles in Cu matrix, display surface nanofeatures, which induce substantial grain refinement and stabilization down to the ultrafine/nano scale. The UFG Cu/Cr B and Cu/CrB_(2) samples exhibit exceptional thermal stability, comparable to UFG Cu induced by nanoparticles, without coarsening after annealing at 600°C for 1 h. The microhardness, strengths, and Young's moduli of the Cu/Cr B and Cu/CrB_(2) samples are significantly enhanced over pure Cu. This discovery has great potential to advance the mass production UFG/nanocrystalline for widespread applications.

关键词： Copper Microparticles with nanofeatures Casting Ultrafine grains Thermal stability

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

Standing surface acoustic wave-assisted fabrication of patterned microstructures for enhancing cell migration

引用

Bio-Design and Manufacturing 2020年第2期3卷 87-97页

作者： Yancheng Wang Yue Wang Deqing Mei Zongkai Yu Dai Xue State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China department of Aerospace and mechanical engineering The George Washington UniversityWashingtonDC 20052USA

Microfluidic device with patterned microstructures on the substrate surface was used to regulate cell adhesion,morphology,and functions in tissue *** developed a microfluidic device which employing microscale patterned microstructures to achieve enhanced cell adhesion and *** hydrogel substrates with micro-wavy and lattice-patterned microstructures were fabricated using standing surface acoustic waves and ultraviolet *** seeding the L929 mouse fibroblast cells onto the patterned substrate of the microfluidic device,we determined that the viability and proliferation rate of cell migration can be greatly ***,L929 cells showed two types of gathering modes after 48 h of *** growth was guided by the patterned substrate used in the microfluidic device and showed differences in the location ***,the developed microfluidic device with patterned microstructures can extend the application of in vitro cell culturing for future drug development and disease diagnosis.

关键词： Standing surface acoustic waves(SSAWs) Micropatterned structure Dynamic cell culture Microfluidic device

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

Surfactant-decorated graphite nanoplatelets(GNPs) reinforced aluminum nanocomposites: sintering effects on hardness and wear

引用

International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 704-715页

作者： Zeeshan Baig Othman Mamat Mazli Mustapha Asad Mumtaz Sadaqat Ali Mansoor Sarfraz department of mechanical engineering Universiti Teknologi PETRONAS department of Fundamental and Applied Sciences Universiti Teknologi PETRONAS Sustainable Energy Technologies Center College of Engineering King Saud University

The exceptional properties of graphene make it ideal as a reinforcement to enhance the properties of aluminum matrices and this critically depends on uniform dispersion. In this study, the dispersion issue was addressed by sonication and non-covalent surface functionalization of graphite nanoplatelets（GNPs） using two types of surfactant： anionic（sodium dodecyl benzene sulfate（SDBS）） and non-ionic polymeric（ethyl cellulose（EC））. After colloidal mixing with Al powder, consolidation was performed at two sintering temperatures（550 and 620°C）. The structure, density, mechanical and wear properties of the nanocomposite samples were investigated and compared with a pure Al and a pure GNPs/Al nanocomposite sample. Noticeably, EC-based 0.5 wt% GNPs/Al samples showed the highest increment of 31% increase in hardness with reduced wear rate of 98.25% at 620°C, while a 22% increase in hardness with reduced wear rate of 96.98% at 550°C was observed, as compared to pure Al. Microstructural analysis and the overall results validate the use of EC-based GNPs/Al nanocomposites as they performed better than pure Al and pure GNPs/Al nanocomposite at both sintering temperatures.

关键词： graphite nanoplatelets (GNPs) aluminum nanocomposites surfactant hardness dispersion ultra-soincation sintering effects

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

Encoding reprogrammable properties into magneto-mechanical materials via topology optimization

引用

npj Computational Materials 2023年第1期9卷 1770-1780页

作者： Zhi Zhao Xiaojia Shelly Zhang department of Civil and Environmental engineering University of Illinois Urbana-ChampaignUrbanaILUSA department of mechanical Science and engineering University of Illinois Urbana-ChampaignUrbanaILUSA

The properties of materials and structures typically remain fixed after being designed and *** is a growing interest in systems with the capability of altering their behaviors without changing geometries or material constitutions,because such reprogrammable behaviors could unlock multiple functionalities within a single *** introduce an optimization-driven approach,based on multi-objective magneto-mechanical topology optimization,to design magneto-active metamaterials and structures whose properties can be seamlessly reprogrammed by switching on and off the external stimuli *** optimized material system exhibits one response under pure mechanical loading,and switches to a distinct response under joint mechanical and magnetic *** discover and experimentally demonstrate magneto-mechanical metamaterials and metastructures that realize a wide range of reprogrammable responses,including multi-functional actuation responses,adaptable snap-buckling behaviors,switchable deformation modes,and tunable *** proposed approach paves the way for promising applications such as magnetic actuators,soft robots,and energy harvesters.

关键词： deformation optimization topology

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

Discovering plasticity models without stress data

引用

npj Computational Materials 2022年第1期8卷 857-866页

作者： Moritz Flaschel Siddhant Kumar Laura De Lorenzis department of mechanical and Process engineering ETH Zürich8092ZürichSwitzerland department of Materials Science and engineering Delft University of Technology2628 CDDelftThe Netherlands

We propose an approach for data-driven automated discovery of material laws,which we call EUCLID(Efficient Unsupervised Constitutive Law Identification and Discovery),and we apply it here to the discovery of plasticity models,including arbitrarily shaped yield surfaces and isotropic and/or kinematic hardening *** approach is unsupervised,i.e.,it requires no stress data but only full-field displacement and global force data;it delivers interpretable models,i.e.,models that are embodied by parsimonious mathematical expressions discovered through sparse regression of a potentially large catalog of candidate functions;it is one-shot,i.e.,discovery only needs one *** material model library is constructed by expanding the yield function with a Fourier series,whereas isotropic and kinematic hardening is introduced by assuming a yield function dependency on internal history variables that evolve with the plastic *** selecting the most relevant Fourier modes and identifying the hardening behavior,EUCLID employs physics knowledge,i.e.,the optimization problem that governs the discovery enforces the equilibrium constraints in the bulk and at the loaded boundary of the *** promoting regularization is deployed to generate a set of solutions out of which a solution with low cost and high parsimony is automatically *** virtual experiments,we demonstrate the ability of EUCLID to accurately discover several plastic yield surfaces and hardening mechanisms of different complexity.

关键词： stress plasticity selecting

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

Real-time phase-shift ing techniques for determining the photoelastic parameters: a theoretical comparison

引用

Chinese Optics Letters 2003年第10期1卷 588-590页

作者：雷振坤亢一澜云大真 department of Mechanics School of Mechanical Engineering Tianjin University Tianjin 300072 department of engineering Mechanics Dalian University of Technology Dalian 116024

Among data acquisition techniques in digital photoelasticity, the integrated phase shifting technique (IPST) can real-time analyze the photoelastic parameters at a video rate of the high speed CCD camera. In this paper, fourteen algorithms are described by different configurations of the rotating an analyzer at a constant rate and an output quarter-wave plate at another constant rate. The theoretical comparisons of the algorithms are given by the simulated phase distributions of the isochromatic and isoclinic parameters of the disk under two cases that the load keeps unchangeable or linearly increasing in exposure time of the camera. Then a guideline is given to alleviate the influence of the load changing with time on the IPST.

关键词： Algorithms Digital image storage Phase shift

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

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：