检索结果-南通市图书馆

On the role of sliding friction effect in nonlinear tri-hybrid vibration-based energy harvesting

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1295-1314页

作者： Jiamei WANG Siukai LAI Chen WANG Yiting zhang Zhaolin CHEN Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057Guangdong ProvinceChina Hebei Key Laboratory of Mechanical Reliability for Heavy Equipments and Large Structures Yanshan UniversityQinghuangdao 066000Hebei ProvinceChina School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

This work aims to develop an experimental investigation into the effectiveness of the sliding-mode approach for hybrid vibration-based energy harvesting.A proposed sliding-mode triboelectric-electromagnetic-piezoelectric energy harvesting model involves a cantilever beam with a tip mass exposed to magnetic and frictional *** experimental findings indicate that the system can achieve its peak inter-well oscillation output within a low-frequency range of 4 Hz–6 *** has a lesser impact on the open-circuit voltage output at an excitation acceleration of 1.5g compared with *** distribution of tri-stability changes with the presence of *** model provides a deeper understanding of the influence of the dry friction coefficient(0.2–0.5) on the interactive behaviors of different generator units.

关键词： sliding mode tri-hybrid energy harvesting friction nonlinear behavior

High-frequency magnetic properties of biphase Ce_(2)Fe_(17)N_(3)/α-Fe microflakes with easy-plane anisotropy

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第1期42卷 110-115,I0004页

作者： Ke Wang Hang zhang Yuandong Huang Zhibiao Xu Fashen Li Tao Wang Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou UniversityLanzhou730000China Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou730000China

Soft magnetic composites(SMCs)are effective as magnetic powder cores in an *** to high saturation magnetization,large magnetocrystalline anisotropy and high operating frequency of M(metal)-RE(rear earth)soft magnetic composites,it is possible to miniaturize inductor cores by reducing total loss,especially eddy current loss and excess loss at high *** this article,the characteristics of Ce_(2)Fe_(17)N_(3)/α-Fe(CFN/F)loss per volume and effective permeability reaching a high frequency of 3 MHz are *** biphase CFN/F composite exhibits a high permeability of 16 at 70 MHz,which is two times greater than that of pure Ce_(2)Fe_(17)N_(3)(CFN)*** total loss is as low as 545 mW/cm^(3)at 3 MHz and 6 *** direct current(DC)-bias properties have a percent of permeability exceeding 65% at H=7960 A/*** phenomenon indicates that our material has a higher working frequency and lower core loss than other materials;the biphase CFN/F structure is a promising and efficient approach for developing the miniaturized radio frequency(RF)inductor core.

关键词： High frequency Soft magnetic composites Easy-plane anisotropy Permeability spectra Core loss Rare earths

miR‑423 sponged by lncRNA NORHA inhibits granulosa cell apoptosis

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2024年第2期15卷 632-644页

作者： Yuqi Li Zhuofan zhang Siqi Wang Xing Du Qifa Li College of Animal Science and Technology Nanjing Agricultural UniversityNanjing 210095China

Background Atresia and degeneration,a follicular developmental fate that reduces female fertility and is triggered by granulosa cell(GC)apoptosis,have been induced by dozens of ***,we report a miRNA,miR-423,that inhibits the initiation of follicular atresia(FA),and early apoptosis of *** We showed that miR-423 was down-regulated during sow FA,and its levels in follicles were negatively correlated with the GC density and the P4/E2 ratio in the follicular fluid in *** in vitro gain-of-function experiments revealed that miR-423 suppresses cell apoptosis,especially early apoptosis in *** speaking,the miR-423 targets and interacts with the 3’-UTR of the porcine SMAD7 gene,which encodes an apoptosis-inducing factor in GCs,and represses its expression and pro-apoptotic ***,FA and the GC apoptosis-related lncRNA NORHA was demonstrated as a ceRNA of ***,we showed that a single base deletion/insertion in the miR-423 promoter is significantly associated with the number of stillbirths(NSB)trait of *** These results demonstrate that miR-423 is a small molecule for inhibiting FA initiation and GC early apoptosis,suggesting that treating with miR-423 may be a novel approach for inhibiting FA initiation and improving female fertility.

关键词： Granulosa cell apoptosis miR-423 NORHA SMAD7 Sow fertility traits

The autophagy protein Atg9 functions in glia and contributes to parkinsonian symptoms in a Drosophila model of Parkinson’s disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第5期19卷 1150-1155页

作者： Shuanglong Yi Linfang Wang Margaret S.Ho Shiping zhang School of Life Science and Technology ShanghaiTech UniversityShanghaiChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy *** in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Parkinson’s ***,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the *** the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult *** from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network,autophagosomes,and lysosomes in ***9 is persistently in contact with these *** glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate *** suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic ***,loss of glial atg9 induces parkinsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial *** findings identify a functional role of Atg9 in glial autophagy and establish a potential link between glial autophagy and Parkinson’s *** results may provide new insights on the underlying mechanism of Parkinson’s disease.

关键词： Atg9 autophagy glia Parkinson’s disease

Effect of Vacancy Defects on the Properties of CoS_(2) and FeS_(2)

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 627-638页

作者：冯中营 zhang Jianmin WANG xiaowei YANG Wenjin JING Yinlan YANG Yan Department of Science Taiyuan Institute of TechnologyTaiyuan 030008China Computational Physics Research Center Taiyuan In-stitute of TechnologyTaiyuan 030008China College of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Department of Physics College of ScienceNorth University of ChinaTaiyuan 030051China

In order to explore the effect of vacancy defects on the structural,electronic,magnetic and optical properties of CoS_(2) and FeS_(2),first-principles calculation method was used to investigate the *** calculated results of materials without vacancy are consistent with those reported in the literatures,while the results of materials with vacancy defect were different from those of literatures due to the difference vacancy *** Co vacancy defect hardly changes the half-metallic characteristic of CoS_(2).The Fe vacancy defect changes FeS_(2) from semiconductor to half-metal,and the bottom of the spin-down conduction band changes from the p orbital state of S to the d(t_(2g))orbital state of Fe,while the top of the valence band remains the d orbital d(eg)state of *** half-metallic Co vacancy defects of CoS_(2) and Fe vacancy defects of FeS_(2) are expected to be used in spintronic devices.S vacancy defects make both CoS_(2) and FeS_(2) *** the Co and S vacancy defects lead to the decrease of the magnetic moment of CoS_(2),while both the Fe and S vacancy defects lead to the obvious magnetic property of FeS_(2).Vacancy defects enhance the absorption coefficient of infrared band and long band of visible light obviously,and produce obvious red shift phenomenon,which is expected to be used in photoelectric devices.

关键词： cobalt disulfide iron disulfide vacancy defect fist principles

Robust multi-sensor image matching based on normalized self-similarity region descriptor

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第1期37卷 271-286页

作者： Xuecong LIU Xichao TENG Jing LUO zhang LI Qifeng YU Yijie BIAN College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China High-Tech Institute Qingzhou 262500China

Multi-modal image matching is crucial in aerospace applications because it can fully exploit the complementary and valuable information contained in the amount and diversity of remote sensing ***,it remains a challenging task due to significant non-linear radiometric,geometric differences,and noise across different *** improve the performance of heterologous image matching,this paper proposes a normalized self-similarity region descriptor to extract consistent structural *** first construct the pointwise self-similarity region descriptor based on the Euclidean distance between adjacent image blocks to reflect the structural properties of multi-modal ***,a linear normalization approach is used to form Modality Independent Region Descriptor(MIRD),which can effectively distinguish structural features such as points,lines,corners,and flat between multi-modal *** further improve the matching accuracy,the included angle cosine similarity metric is adopted to exploit the directional vector information of multi-dimensional feature *** experimental results show that the proposed MIRD has better matching accuracy and robustness for various multi-modal image matching than the state-of-the-art *** can effectively extract consistent geometric structure features and suppress the influence of SAR speckle noise using non-local neighboring image blocks operation,effectively applied to various multi-modal image matching.

关键词： Remote sensing Multi-modal image matching Template matching Feature descriptor Similarity metric Synthetic Aperture Radar(SAR)

Material flow analysis and global warming potential assessment of an industrial insect-based bioconversion plant using housefly larvae

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第5期139卷 483-495页

作者： Tao Lu Fan Lü Nanlin Liao Honghui Chai Hua zhang Pinjing He Institute of Waste Treatment and Reclamation Tongji UniversityShanghai 200092China State Key Laboratory of Pollution Control and Source Reuse Tongji UniversityShanghai 200092China Zhejiang Qihe Ecological Technology Co. Ltd.Hangzhou 310052China

The significant increase in the demand for biomass waste treatment after garbage classification has led to housefly larvae treatment becoming an attractive treatment *** can provide a source of protein while treating biomass waste,which means that nutrients can be returned to the natural food ***,the performance of this technology in terms of its environmental impacts is still unclear,particularly with regards to global warming potential(GWP).This study used a life cycle assessment(LCA)approach to assess a housefly larvae treatment plant with a treatment capacity of 50 tons of biomass waste per *** LCA results showed that the 95% confidence intervals for the GWP in summer and winter were determined to be 24.46-32.81 kg CO_(2) equivalent(CO_(2)-eq)/ton biomass waste and5.37-10.08 kg CO_(2)-eq/ton biomass waste,*** greater GWP value in summer is due to the longer ventilation time and higher ventilation intensity in summer,which consumes more *** main GWP contributions are from(1)electricity needs(accounting for 78.6% of emissions in summer and 70.2%in winter)and(2)product substitution by mature housefly larvae and compost(both summer and winter accounting for 96.8% of carbon reduction).

关键词： Biomass waste Musca domestica Housefly larvae Life cycle assessment Global warming potential

Numerical analysis of wind effects on aerodynamic characteristics of a ducted fan

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第5期37卷 263-280页

作者： Yiwei LUO Tianfu AI Yuhang HE Bin XU Yuping QIAN Yangjun zhang State Key Laboratory of Intelligent Green Vehicle and Mobility School of Vehicle and MobilityTsinghua UniversityBeijing 100084China Key Laboratory of Conveyance and Equipment Ministry of Education East China Jiaotong UniversityNanchang 330013China Vehicle Research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Ducted fans have been extensively used in Unmanned Aerial Vehicles(UAVs)for a variety of missions because of high efficiency,high safety and low ***,as a kind of typical meteorological condition,brings significant aerodynamic interference to the ducted fan,which seriously threatens flight stability and *** this work,the numerical simulation with the Unsteady Reynolds Averaged Navier-Stokes(URANS)method and the sliding mesh technique is performed to evaluate the steady wind *** results show that the wind will lead to serious unsteady effects in the flow field,and the thrust fluctuates at the blade passing frequency of 200 *** the wind speed increases,the rotor thrust increases,the duct thrust decreases,and the total thrust changes *** instability may occur when the wind speed exceeds 8 m/*** the angle of low-speed wind increases,the rotor thrust changes little,the duct thrust increases,and the total thrust *** addition,we figure out that cases with the same crosswind ratio are similar in results,and increasing the rotating speed or fan radius is beneficial to performance improvement in *** findings are essential to the ducted fan design and UAV flight control design for stable and safe operations in wind conditions.

关键词： Unmanned Aerial Vehicle(UAV) Ducted fan Wind effect Thrust fluctuations Computational Fluid Dynamics(CFD)

Wireless semantic communication based on semantic matching multiple access and intent bias multiplexing

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 26-36页

作者： Ren Chao He Zongrui Sun Chen Li Haojin zhang Haijun University of Science and Technology Beijing Beijing 100083China Research and Development Center Sony(China)LimitedBeijing 100027China

This paper proposes a multi-access and multi-user semantic communication scheme based on semantic matching and intent deviation to address the increasing demand for wireless users and *** scheme enables flexible management of long frames,allowing each unit of bandwidth to support a higher number of *** leveraging semantic classification,different users can independently access the network through the transmission of long concatenated sequences without modifying the existing wireless communication *** overcome the potential disadvantage of incomplete semantic database matching leading to semantic intent misunderstanding,the scheme proposes using intent deviation as an *** allows different receivers to interpret the same semantic information differently,enabling multiplexing where one piece of information can serve multiple users with distinct *** results show that at a bit error rate(BER)of 0.1,it is possible to reduce the transmission by approximately 20 semantic basic units.

关键词： semantic communication multiple access multiplexing multimodal communication