检索结果-南通市图书馆

Analytical Solutions for an Isotropic Elastic Half-Plane with Complete Surface Effects Subjected to a Concentrated/Uniform Surface Load

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2024年第3期37卷 371-384页

作者： Xia-Hui Pan school of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

Within the context of Gurtin-Murdoch surface elasticity theory,closed-form analytical solutions are derived for an isotropic elastic half-plane subjected to a concentrated/uniform surface *** the effects of residual surface stress and surface elasticity are *** stress function method and Fourier integral transform technique are *** solutions are provided in a compact manner that can easily reduce to special situations that take into account either one surface effect or none at *** results indicate that surface effects generally lower the stress levels and smooth the deformation profiles in the *** elasticity plays a dominant role in the in-plane elastic fields for a tangentially loaded half-plane,while the effect of residual surface stress is fundamentally crucial for the out-of-plane stress and displacement when the half-plane is normally *** the remaining situations,combined effects of surface elasticity and residual surface stress should be *** results for a concentrated surface force serve essentially as fundamental solutions of the Flamant and the half-plane Cerruti problems with surface *** solutions presented in this work may be helpful for understanding the contact behaviors between solids at the nanoscale.

关键词： Surface effects Residual surface stress Surface elasticity Half-plane Analytical solutions

Investigation on occupant presence and appliance operation schedules for university campus in south China sub-tropical area

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

Building Simulation 2024年第2期17卷 301-318页

作者： Siwei Lou Zhongyuan Lin Yukai Zou Dawei Xia Yu Huang Zhuohong Li Zhaowen Gu school of Civil Engineering Guangzhou UniversityGuangzhou Higher Edu.Mega CenterGuangzhouChina school of Architecture and Urban Planning Guangzhou UniversityGuangzhou Higher Edu.Mega CenterGuangzhouChina

Building occupant presence during varying periods is crucial to the performance studies of buildings and city ***,the understanding of the building occupancies on the university campus remains *** address this gap,our study employs field measurements,payment records,course arrangements,and building access systems to depict the occupancy patterns of the canteen,dormitory,library,and teaching and lab buildings during weekdays and *** found that the occupancy rates across different buildings are somehow interrelated,given that the total number of occupants on campus is generally ***,dormitory occupancy rates tend to be low during the morning and afternoon course hours,which inversely correlates with the high occupancy rates in the teaching and lab buildings during these ***,canteens experience surges in occupancy during meal times,which coincide with a decrease in library ***,we established appliance operation schedules for dormitories through surveys and on-site *** dispensers and electronic devices were identified as the primary energy consumers for both male and female occupants,with desk-top fans and hairdryers being significant energy users for male and female occupants,*** findings are essential for energy studies within a campus setting,underlining the importance of considering occupant behaviors on a regional scale.

关键词： building occupant behavior university campus occupancy schedule appliance operation schedule

No Reference Image Sharpness Assessment Based on Global Color Difference Variation

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

Chinese Journal of Electronics 2024年第1期33卷 293-302页

作者： Chenyang SHI Yandan LIN school of Artificial Intelligence Anhui Polytechnic University school of Mechanical Engineering Anhui Polytechnic University Department of Light Sources and Illuminating Engineering Fudan University Academy for Engineering & Technology Fudan University

Image quality assessment(IQA) model is designed to measure the image quality in consistent with subjective ratings by computational models. In this research, a valid no reference IQA(NR-IQA) model for color image sharpness assessment is proposed based on local color difference map in a color space. In the proposed model, the absolute color difference variation and relative color difference variation are combined to evaluate sharpness in YIQ color space(a color coordinate system for the development of the United States color television system). The difference between sharpest and blurriest spot of an image is represented by the absolute color difference variation, and relative color difference variation expresses the variation in the image content. Extensive experiments are performed on five publicly available benchmark synthetic blur databases and two real blur databases, and the results prove that the proposed model work better than the other state-of-the-art and latest NR-IQA models for the prediction accuracy on blurry images. Besides, the model maintains the lowest computational complexity.

关键词： Image quality TV Image color analysis Databases Computational modeling Color Predictive models

Effect of Oxygen-Rich Combustion on Flame Propagation of Syngas in a Half-Open Pipe at Elevated Temperatures

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第5期33卷 1920-1934页

作者： LI Ningning DENG Haoxin XU Zhuangzhuang YAN Mengmeng WEI Shengnan SUN Guangzhen WEN Xiaoping GAN Haowen WANG Fahui school of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454003China

The investigation of syngas flame propagation has great benefits for the effective use of gas *** essay sets out to study the flame propagation of premixed oxygen-rich combustion(oxygen enrichment coefficient in volumeΩ:0.21,0.27,0.32,0.37)of syngas(H_(2):CO=2:8)in half-closed rectangular ducts at elevated temperatures(T:300 K,400 K,500 K)and evaluate the effects of initial temperature and oxygen enrichment coefficient on the LBV from sensitivity analysis and kinetic *** paper presents the effect of the expansion effect on laminar burning velocity for the first time,and separates the effect of the expansion effect on laminar burning velocity by a new *** shows that as the initial temperature goes up,the faster the exponential growth phase of the flame front velocity,the slower the slow growth *** smaller and earlier the maximum flame front velocity arrives,the slower the average flame speed *** the oxygen enrichment coefficient goes up,the peak value of the flame front velocity gradually ***-rich combustion and increasing initial temperature inhibit flame propagation in a half-open tube,but promote laminar burning velocity,which increases the key chemical bond and adiabatic flame *** net reaction rate shows that oxygen-rich combustion mainly promotes the combustion reaction of H_(2)(R2).However,increasing the initial temperature mainly promoted the oxidation of CO(R29).Analysis of the reaction path showed that oxygen-rich combustion and increased initial temperature promoted the reaction of H_(2)and CO with key chemical bonds,increased OH concentration,and inhibited OH cracking reaction.

关键词： gas turbines oxyfuel combustion numerical simulation combustion kinetics fire and flame

Prediction of undeformed chip thickness distribution and surface roughness in ultrasonic vibration grinding of inner hole of bearings

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 311-323页

作者： Yanqin LI Daohui XIANG Guofu GAO Feng JIAO Bo ZHAO school of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

Ultrasonic vibration grinding differs from traditional grinding in terms of its material removal *** randomness of grain-workpiece interaction in ultrasonic vibration grinding can produce variable chips and impact the surface roughness of ***,previous studies used iterative method to calculate the unformed chip thickness(UCT),which has low computational *** this study,a symbolic difference method is proposed to calculate the *** UCT distributions are obtained to describe the stochastic interaction characteristics of ultrasonic grinding ***,the UCT distribution characteristics under different machining parameters are ***,a surface roughness prediction model is established based on the UCT ***,the correctness of the model is verified by *** study provides a quick and accurate method for predicting surface roughness in longitudinal ultrasonic vibration grinding.

关键词： Ultrasonic vibration grinding Undeformed chip thickness(UCT) Distribution characteristics Surface roughness

Constraints on the primordial curvature power spectrum by pulsar timing array data:a polynomial parameterization approach

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

Communications in Theoretical Physics 2024年第1期76卷 96-104页

作者： Qin Fei school of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China

The recent stochastic signal observed jointly by NANOGrav,parkes pulsar timing array,European pulsar timing array,and Chinese pulsar timing array can be accounted for by scalarinduced gravitational waves(SIGWs).The source of the SIGWs is from the primordial curvature perturbations,and the main contribution to the SIGWs is from the peak of the primordial curvature power *** effectively model this peak,we apply the Taylor expansion to parameterize *** the Taylor expansion parameterization,we apply Bayesian methods to constrain the primordial curvature power spectrum based on the NANOGrav 15 year data *** constraint on the primordial curvature power spectrum possesses a degree of generality,as the Taylor expansion can effectively approximate a wide range of function profiles.

关键词： pulsar timing array scalar-induced gravitational waves inflation

Biocatalytic enhancement of laccase immobilized on ZnFe_(2)O_(4) nanoparticles and its application for degradation of textile dyes

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第4期68卷 216-223页

作者： Yuhang Wei Qingpeng Zhu Weiwei Xie Xinyue Wang Song Li Zhiming Chen school of Chemical and Environmental Engineering Anhui Laboratory of Functional Coordinated Complexes for Materials Chemistry and ApplicationAnhui Polytechnic UniversityWuhu 241000China school of Biology and Food Engineering Anhui Polytechnic UniversityWuhu 241000China

Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal *** work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on amino-functionalized ZnFe_(2)O_(4) nanoparticles(ZnFe_(2)O_(4)-laccase)and its application for the degradation of textile *** to the existence of a large number of oxygen vacancies on the surface of the ZnFe_(2)O_(4) nanoparticles,negative ions accumulated on the magnetic carriers,which resulted in a harsh optimal pH value of the ZnFe_(2)O_(4)-*** activity assays revealed that the ZnFe_(2)O_(4)-laccase possessed superior pH and thermal stabilities,excellent reusability,and noticeable organic solvent ***,the ZnFe_(2)O_(4) laccase presented efficient and sustainable degradation of high concentrations of textile *** initial decoloration efficiencies of malachite green(MG),brilliant green(BG),azophloxine,crystal violet(CV),reactive blue 19(RB19),and procion red MX-5B were approximately 99.1%,95.0%,93.3%,87.4%,86.1%,and 85.3%,*** 10 consecutive reuses,the degradation rates of the textile dyes still maintained about 98.2%,92.5%,83.2%,81.5%,79.8%and 65.9%,*** excellent dye degradation properties indicate that the ZnFe_(2)O_(4)-laccase has a technical application in high concentrations of dyestuff treatment.

关键词： ZnFe_(2)O_(4)-laccase Catalytic activity Stability and reusability Degradation of textile dye

Research on Modeling and Parameter Identification of Comprehensive Load Model of Distribution Network in Industrial Park

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第1期33卷 264-273页

作者： Tingling WANG Xiaohe YAN school of Electric Engineering North China University of Water Resources and Electric Power Wenzhou polytechnic

With the rapid development of industrial parks, its load model research has become a hot spot. In order to study the load of power system in industrial park, based on the characteristics of the industrial park load, a comprehensive load admittance static model with full voltage range adaptability is considered, and a comprehensive load model of distribution network of the industrial park is established. A complete parameter identification of the model is carried out through chaos particle swarm optimization. The simulation results show that the model can effectively describe the load characteristics of the distribution network in industrial parks.

关键词： Chaos Adaptation models Analytical models Parameter estimation Induction motors Simulation Distribution networks

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第5期76卷 77-85页

作者： Duo Zhang Ke Wang Kunpeng Zhao Mei Wang Zhaoyu Sun school of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property