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Orientation Parameters Estimation and Lens Distortion Correction for UAVs Photogrammetry with Non-metric Cameras
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作者 DENG Xingsheng GAO Yang ZHU Xu 《Journal of Geodesy and Geoinformation Science》 2025年第1期71-88,共18页
The estimation of orientation parameters and correction of lens distortion are crucial problems in the field of Unmanned Aerial Vehicles(UAVs)photogrammetry.In recent years,the utilization of UAVs for aerial photogram... The estimation of orientation parameters and correction of lens distortion are crucial problems in the field of Unmanned Aerial Vehicles(UAVs)photogrammetry.In recent years,the utilization of UAVs for aerial photogrammetry has witnessed a surge in popularity.Typically,UAVs are equipped with low-cost non-metric cameras and a Position and Orientation System(POS).Unfortunately,the Interior Orientation Parameters(IOPs)of the non-metric cameras are not fixed.Whether the lens distortions are large or small,they effect the image coordinates accordingly.Additionally,Inertial Measurement Units(IMUs)often have observation errors.To address these challenges and improve parameter estimation for UAVs Light Detection and Ranging(LiDAR)and photogrammetry,this paper analyzes the accuracy of POS observations obtained from Global Navigation Satellite System Real Time Kinematic(GNSS-RTK)and IMU data.A method that incorporates additional known conditions for parameter estimation,a series of algorithms to simultaneously solve for IOPs,Exterior Orientation Parameters(EOPs),and camera lens distortion correction parameters are proposed.Extensive experiments demonstrate that the coordinates measured by GNSS-RTK can be directly used as linear EOPs;however,angular EOP measurements from IMUs exhibit relatively large errors compared to adjustment results and require correction during the adjustment process.The IOPs of non-metric cameras vary slightly between images but need to be treated as unknown parameters in high precision applications.Furthermore,it is found that the Ebner systematic error model is sensitive to the choice of the magnification parameter of the photographic baseline length in images,it should be set as less than or equal to one third of the photographic baseline to ensure stable solutions. 展开更多
关键词 UAVs photogrammetry non-metric cameras Interior orientation Parameters(IOPs) Exterior orientation Parameters(EOPs) lens distortion correction
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Integrating well logs,3D seismic,and earthquake data for comprehensive prediction of 3D in-situ stress orientations:A case study from the Weiyuan area in the Sichuan Basin,China 被引量:1
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作者 Huan Cao Yang Zhao +4 位作者 Hai-Chao Chen Le-Le Zhang Cheng-Gang Xian Ji-Dong Yang Lu Liu 《Petroleum Science》 2025年第1期210-221,共12页
Determining the orientation of in-situ stresses is crucial for various geoscience and engineering appli-cations.Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(F... Determining the orientation of in-situ stresses is crucial for various geoscience and engineering appli-cations.Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs)derived from earthquake data and formation micro-imager(FMI)data from well logs.However,these techniques can be costly,depth-inaccurate,and may lack spatial coverage.To address this issue,we introduce the use of three-dimensional(3D)seismic data(active sources)as a lateral constraint to approximate the 3D stress orientation field.Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy,we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information.We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin,China,a region targeted for shale gas production.By integrating diverse datasets,including 3D seismic,earthquakes,and well logs,we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes).Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax)obtained from FMIs.We analyzed 12 earthquakes(magnitude>3)recorded between 2016 and 2020 for their FMSs and compressional axis(P-axis)orientations.The derived SHmax direction from our 3D stress model is 110°ES(East-South),which shows excellent agreement with the FMSs(within 3.96°).This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations. 展开更多
关键词 In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager
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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian LI Jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian LI Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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Determination of Fracture Plane Orientation Using the Variance Method under Multiaxial Loading
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作者 Mbaiyelkom Esdras Ngargueudedjim Kimtangar +2 位作者 Bianzeube Tikri Kenmeugne Bienvenu Fogue Médard 《Open Journal of Applied Sciences》 2025年第2期411-424,共14页
The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained expe... The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained experimentally through tests on specimens under multiaxial loading with that calculated by the variance method. In the statistical approach criteria, several methods have been developed but we have presented only one method, namely the variance method using the equivalent stress. She assumes that the fracture plane orientation is the one on which the variance of the equivalent stress is maximum. Three types of equivalent stress are defined for this method [1]: normal stress, shear stress and combined normal and shear stress. The results obtained were compared with experimental results for multiaxial cyclic stress states, and it emerges that the variance method for the case of combined loading is conservative as it gives a better prediction of the fracture plane. 展开更多
关键词 Biaxial Fatigue Fracture Plane orientation Critical Fracture Plane Variance Method Fatigue Criteria
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Caffeine-enhanced Zn(0 0 2)texture-oriented growth for stable aqueous zinc-ion batteries
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作者 Zhihong Luo Tingting Xu +8 位作者 Liucheng Cao Qi Liu Degui Li Xiangqun Zhuge Laijun Liu Yibing Li Kun Luo Kai Qi Bao Yu Xia 《Journal of Energy Chemistry》 2025年第8期44-52,共9页
Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired... Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired by using green corrosion inhibitor for metals,we introduce caffeine,extracted from tea-leaf,as an additive to achieve stable AZIBs.Caffeine,with its N and O containing groups,strongly adsorbs on the Zn anode and Zn^(2+)ions.This featured adsorption induces the replacement of water molecules from electric double layer(EDL)and solvation shell,suppressing side-reactions such as corrosion and hydrogen evolution reaction(HER).Moreover,the selective adsorption and steric hindrance of caffeine promote Zn(002)-oriented deposition,resulting in uniform and compact zinc deposits at both low and high current density and areal capacity.Due to the significantly suppressed dendrites and corrosion,the Coulomb Efficiency(CE)reaches 99.24%after 800 cycles,and the Zn||MnO_(2)battery shows a specific capacity of 167.2 mAh g^(−1)with 81%capacity retention after 1000 cycles at 2 A g^(−1). 展开更多
关键词 Zn-ion battery Zn dendrites CAFFEINE Adsorption oriented growth
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Origin of misorientations for fcc→hcp transformation in pure cobalt and its in-situ validation
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作者 Jin-jiang HE Guo-jin XU +4 位作者 Xing-quan WANG Jun-feng LUO Dan LIU Yong-jun LI Xin-fu GU 《Transactions of Nonferrous Metals Society of China》 2025年第5期1532-1542,共11页
The origin of the misorientations after fcc(face-centered cubic)to hcp(hexagonal close-packed)transformation in pure cobalt was elucidated by utilizing the electron backscatter diffraction(EBSD)technique and transform... The origin of the misorientations after fcc(face-centered cubic)to hcp(hexagonal close-packed)transformation in pure cobalt was elucidated by utilizing the electron backscatter diffraction(EBSD)technique and transformation crystallographic models.It is found the Shoji−Nishiyama orientation relationship during fcc→hcp transformation leads to four hcp variants,characterized by a common misorientation angle of 70.5°with respect to the<1120>direction,which is the predominant misorientation observed.Other statistically significant misorientation angles between hcp grains,including 32°,36°,38°,60°,71°and 86°−91°,are also identified.These newly observed misorientation angles are linked to the microstructure of the fcc matrix at elevated temperatures,with twin structures in the fcc matrix being the primary cause.Furthermore,a novel method is proposed for estimating the fraction of twins in the fcc grains based on misorientation angles between hcp variants,which is found to be consistent with experimental observations.In-situ EBSD observations validate the possible origin of fcc twins from the hcp→fcc transformation. 展开更多
关键词 COBALT transformation crystallography VARIANT orientation relationship twin
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How nestlings of Oriental Reed Warbler respond to adult alarm calls
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作者 Jiaojiao Wang Yongrui Feng +3 位作者 Laikun Ma Longwu Wang Canchao Yang Jianhua Hou 《Avian Research》 2025年第3期389-396,共8页
Avian alarm calls mediate defenses against brood parasites and predators. These calls facilitate communication among adults and alert nestlings to potential danger. While heterospecific call recognition has been exten... Avian alarm calls mediate defenses against brood parasites and predators. These calls facilitate communication among adults and alert nestlings to potential danger. While heterospecific call recognition has been extensively studied in adult birds, nestlings—lacking direct predation experience and heterospecific alarm exposure—represent an ideal system to investigate the response to interspecific warning cues. This study explored the recognition capabilities of 5–6-day-old nestlings in Oriental Reed Warbler (Acrocephalus orientalis), a common host of the Common Cuckoo (Cuculus canorus). We exposed the nestlings to playbacks of alarm calls directed at parasites and raptors from conspecific, Vinous-throated Parrotbill (Sinosuthora webbiana, sympatric species), Isabelline Shrike (Lanius isabellinus, allopatric species) and Common Tailorbird (Orthotomus sutorius, allopatric species) adults. Results indicated that there was no significant difference in the responses of nestlings to the alarm calls of conspecific and allopatric adults directed at cuckoos and sparrowhawks. In addition, interestingly, nestlings significantly reduced their begging in response to conspecific and unfamiliar allopatric Isabelline Shrike and Common Tailorbird alarm calls but exhibited a weak response to the sympatric Vinous-throated Parrotbill. Whether older warbler nestlings with more social experience exhibit stronger responses to the alarm calls of Vinous-throated Parrotbill adults requires further investigation. 展开更多
关键词 Alarm call Altricial nestling oriental Reed Warbler PARASITE PREDATOR
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Optimization of Talent Cultivation Strategies for Bioengineering Majors under Employment Orientation
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作者 Liqin YIN Yan WAN +2 位作者 Li HAO Yuanmou TANG Yanli XIA 《Agricultural Biotechnology》 2025年第5期77-80,85,共5页
The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed ... The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed that while employment placement rates for bioengineering graduates remain stable,starting salaries exhibit limited growth and career trajectories lack clarity.These challenges originate from a curriculum lagging behind technological progress,inadequate practical training,and a mismatch between student competencies and industry expectations.To address these issues,this paper proposed a strategic framework grounded in"demand-driven design,industry-education integration,and competence-centered development".Key strategies include dynamic curriculum renewal,collaborative university-industry training,holistic competency development,and personalized student support,which collectively aim at enhancing graduates employment competitiveness and long-term professional sustainability. 展开更多
关键词 BIOENGINEERING Biology major Employment orientation Employment quality Talent cultivation Training strategy
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Assessing the effect of plot size on species diversity in a mixed oriental beech forest
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作者 Narges Kardgar Ramin Rahmani +1 位作者 Habib Zare Somayeh Ghorbani 《Journal of Forestry Research》 2025年第1期209-222,共14页
Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fag... Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fagus orientalis Lipsky),a widespread species in the Hyrcanian region.Assessing the impacts of plot size on species diversity is fundamental for an ecosystem-based approach to forest management.This study determined the relation of species diversity and plot size by investigating species richness and abundance of both canopy and forest floor.Two hundred and fifty-six sample plots of 625 m^(2) each were layout in a grid pattern across 16 ha.Base plots(25 m×25 m)were integrated in different scales to investigate the effect of plot size on species diversity.The total included nine plots of 0.063,0.125,0.188,0.250,0.375,0.500,0.563,0.750 and 1 ha.Ten biodiversity indices were calculated.The results show that species richness in the different plot sizes was less than the actual value.The estimated value of the Simpson species diversity index was not significantly different from actual values for both canopy and forest floor diversity.The coefficient of variation of this index for the 1-ha sample plot showed the lowest amount across different plot sizes.Inverse Hill species diversity was insignificant difference across different plot sizes with an area greater than 0.500 ha.The modified Hill evenness index for the 1-ha sample size was a correct estimation of the 16-ha for both canopy and forest floor;however,the precision estimation was higher for the canopy layer.All plots greater than 0.250-ha provided an accurate estimation of the Camargo evenness index for forest floor species,but was inaccurate across different plot sizes for the canopy layer.The results indicate that the same plot size did not have the same effect across species diversity measurements.Our results show that correct estimation of species diversity measurements is related to the selection of appropriate indicators and plot size to increase the accuracy of the estimate so that the cost and time of biodiversity management may be reduced. 展开更多
关键词 Species diversity oriental beech forest Sample plot size Richness EVENNESS
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Strength-based concurrent design for structural topology and building orientation of additively manufactured lattice structure
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作者 Chenyang LI Yamin LI +3 位作者 Shangqin YUAN Shaoying LI Jihong ZHU Weihong ZHANG 《Chinese Journal of Aeronautics》 2025年第9期540-558,共19页
A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and ... A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and structural yield strength can be simultaneously adjusted by integrating the overall process-structure-performance relationship of the AM process into the optimization.Specifically,the transverse isotropic material model is adopted to describe the material properties induced by the layer-by-layer manner of additive manufacturing.To bolster lattice strength performance,the stress constraints and ratio constraints of lattice struts are employed.The Tsai-Wu yield criterion is implemented to characterize the lattice strut's strength,while the P-norm method streamlines the handling of multiple constraints,minimizing computational overhead.Moreover,the gradient-based optimization model is established,where both the individual struts diameters and BO can be designed,and the buckling-prone spatial struts are strategically eliminated to improve the lattice strength further.Furthermore,several typical structures are optimized to verify the effectiveness of the proposed method.The optimized results are quite encouraging since the heterogeneous lattice structures with optimized BO obtained by the strength-based concurrent method show a remarkably improved performance compared to traditional designs. 展开更多
关键词 Strength-based design AM-driven design Concurrent design Building orientation Additive manufacturing
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From“Orientalism”to the Eastern Beauty-the Progress of China Pavilions in the Expo
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作者 Wan Zewei 《China's Foreign Trade》 2025年第4期57-58,共2页
The China Pavilion has consistently been the primary vehicle for China's participation in World Expos over the years.From the first China Pavilion at the 1876 Philadelphia Expo to the 2025 China Pavilion at the on... The China Pavilion has consistently been the primary vehicle for China's participation in World Expos over the years.From the first China Pavilion at the 1876 Philadelphia Expo to the 2025 China Pavilion at the ongoing Osaka Expo,nearly 150 years have passed.During this span,the China Pavilion at the Expos. 展开更多
关键词 china pavilion world expos China Pavilion World Expo Eastern Beauty orientALISM
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A Study on the Theme Orientation and Emotional Identity of Metaphorical Network Hot Words in Short Videos
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作者 ZHANG Wei-jie 《Journal of Literature and Art Studies》 2025年第4期310-316,共7页
In the wave of internet culture,short videos have become an indispensable medium for social communication.The metaphorical hot words contained within them serve as a unique linguistic phenomenon that leads topics and ... In the wave of internet culture,short videos have become an indispensable medium for social communication.The metaphorical hot words contained within them serve as a unique linguistic phenomenon that leads topics and focuses attention,greatly enriching the expressive layers and rhetorical charm of short videos,and significantly enhancing the video’s theme orientation and emotional identification.This research aims to explore the relationship between the use of metaphorical Internet buzzwords in short videos and the thematic and emotional orientation.The study adopts a combination of qualitative and quantitative methods,taking 10 videos with over 10,000 likes posted by a well-known blogger on Xiaohongshu in 2024 as the research object,transcribing the text,forming research corpora,and conducting multi-dimensional cognitive analysis on them.The study shows that about half of short videos contain metaphorical hot words.Different types of metaphorical hot words can trigger different emotional reactions from fans,especially humorous metaphorical hot words that can stimulate fans’emotional identification and resonance.In addition,in terms of fan participation,videos using metaphorical hot words tend to attract more fan attention than those that do not:these videos not only attract more fans to watch and like,but also trigger more comments and sharing behaviors.In summary,short videos cleverly use metaphors to create internet hot words,significantly enhancing the video’s thematic guidance and emotional resonance,manifested in creating popular topics,clarifying guiding themes,enhancing content attractiveness,and stimulating strong emotional identification,thereby promoting interactive behaviors such as likes and shares.These findings provide a reference for research in related fields such as metaphor,communication studies,and sociology. 展开更多
关键词 short videos internet hot words metaphor theme orientation emotional identity
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Spatiotemporal characteristics of Neolithic tomb orientations in Central China informed by machine learning
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作者 ZHANG Xing LU Peng +1 位作者 CHEN Panpan WANG Zhen 《Journal of Geographical Sciences》 2025年第8期1793-1814,共22页
The orientations of ancient tombs have attracted increasing scholarly attention,as they offer valuable insights into early social structures,cultural traditions,and the relationship between humans and their environmen... The orientations of ancient tombs have attracted increasing scholarly attention,as they offer valuable insights into early social structures,cultural traditions,and the relationship between humans and their environment.However,the application of machine learning algorithms to the study of tomb orientation remains relatively underexplored.In this study,we employed a Gaussian mixture model to conduct a systematic analysis of the spatial and temporal evolution of Neolithic tomb orientations in Central China.We also examined the relationship between tomb orientation and both environmental factors and sociocultural dynamics.The findings suggest a deliberate and methodical approach to the planning and alignment of tombs during the Neolithic Age.Tomb orientations in each chronological phase displayed clear clustering patterns,reflecting a developmental trajectory from uniformity to diversity,and ultimately toward integration.While early angular measurement techniques appear to have emerged,they do not show evidence of sustained technical progression.Instead,different periods seem to have achieved similar levels of directional accuracy.The predominance of westward-facing tombs may be closely tied to both topographic features and the symbolic association with sunset.At the same time,cultural evolution and interregional exchange played essential roles in shaping the distinctive patterns of prehistoric tomb orientation.This research contributes not only to the understanding of ancient funerary practices but also demonstrates the potential of machine learning and artificial intelligence technologies in advancing archaeological analysis. 展开更多
关键词 Central China Neolithic Age tomb orientations machine learning human-environment interaction
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Unleashing high-efficiency mass-charge transfer in Bi OBr anodes for aqueous batteries via targeted(110)plane orientation
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作者 Hanqing Liu Tingting Y.K.Qin +8 位作者 Yingguang Zhang Xiaolong Zhao Wei Dong Zhenfei Chang Sarah K.W.Leong Rafa Zarin Meng Ni Dennis Y.C.Leung Wending Pan 《Journal of Energy Chemistry》 2025年第4期749-758,共10页
Bismuth oxybromide(BiOBr)is being actively researched as a promising anode material for aqueous batteries due to its unique layered structure,which theoretically allows for efficient ion diffusion.However,current stud... Bismuth oxybromide(BiOBr)is being actively researched as a promising anode material for aqueous batteries due to its unique layered structure,which theoretically allows for efficient ion diffusion.However,current studies have come across many challenges,e.g.serious capacity degradation and inferior rate capability caused by severe structural collapse and sluggish reaction kinetics,highlighting the need for further improvement in efficient utilization of the layered space.Herein,this study employs a novel crystal orientation regulation to enhance the performance of BiOBr electrode by a facile solvothermal method to efficiently utilize the interlayered structu re.The delicate design of BiOBr(BOB)succeeds in maximizing the exposed(110)crystalline plane,providing efficient pathways for ion diffusion and streamlining the mass migration process.Moreover,the optimized band structure and the formation of oxygen vacancies in this designed material have been found,enabling high electrical conductivity,accelerating the charge transfer process and facilitating rapid reaction rate.Owing to the simultaneously enhanced mass transfer at the interlayers and the charge transfer during the phase conversion process,the BOB-110 electrode exhibits exceptional electrochemical performances,boasting impressive charge storage and rate capability(159 mAh g^(-1)at 4 A g^(-1)),and outstanding cycling stability of capacity retention around 75%(119 mAh g^(-1))even after 1000 cycles at a high current density of 4 A g^(-1).These findings underscore the substantial potential of BiOBr electrodes for future energy storage devices such as wearable electronics and power grids where the power output,lifespan,and affordability are simultaneously required. 展开更多
关键词 Aqueous battery BiOBr Crystal orientation Energy band structure
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Study on the influence of fiber orientation on the stress state in the cfrp cutting process
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作者 WANG Yiqi LI Xiang +3 位作者 SANG Yunfei YU Jiadi CHEN Liangzi TANG Shanshan 《纤维复合材料》 2025年第3期8-11,26,共5页
Carbon fiber reinforced polymer(CFRP)composites,as a typical difficult-to-machine material,exhibit high cutting forces and temperatures during actual machining,leading to more severe tool wear compared to traditional ... Carbon fiber reinforced polymer(CFRP)composites,as a typical difficult-to-machine material,exhibit high cutting forces and temperatures during actual machining,leading to more severe tool wear compared to traditional metal ma-terials.The shear fracture during fiber cutting is incomplete,resulting in surface defects such as unclosed fibers and burrs.To analyze the cutting forces and tool wear areas when cutting CFRP with different fiber angles,a three-dimensional or-thogonal cutting model of CFRP was established using finite element software and the VUMAT subroutine,based on the three-dimensional Hashin criterion.Simulation results show that during the cutting process of CFRP,high-stress areas appear in the region where the cutting edge contacts the workpiece for each fiber orientation,primarily concentrated in the first deformation zone in contact with the cutting edge.The Mises stress is highest when cutting the 90°fibers and lowest when cutting the 0°fibers.When cutting the 0°and 135°fibers,the tool is prone to wear on both the rake and flank faces,while when cutting the 45°and 90°fibers,the tool's rake face is more likely to experience wear. 展开更多
关键词 CFRP three-dimensional hashin criterion fiber orientation finite element
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Fuzzy boundary guidance and oriented Gaussian function-based anchor-free network for rail positioning in turnout sections
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作者 TONG Shuzhen WANG Qing LU Xiaobo 《Journal of Southeast University(English Edition)》 2025年第3期356-365,共10页
Rail positioning is a critical step for detecting rail defects downstream.However,existing orientation-based detectors struggle to effectively manage rails with arbitrary inclinations and high aspect ratios,particular... Rail positioning is a critical step for detecting rail defects downstream.However,existing orientation-based detectors struggle to effectively manage rails with arbitrary inclinations and high aspect ratios,particularly in turnout sections.To address these challenges,a fuzzy boundary guidance and oriented Gaussian function-based anchor-free network termed the rail positioning network(RP-Net)is proposed for rail positioning in turnout sections.First,an oriented Gaussian function-based label generation strategy is introduced.This strategy produces smoother and more accu-rate label values by accounting for the specific aspect ratios and orientations of the rails.Second,a fuzzy boundary learning module is developed to enhance the network’s abil-ity to model the rail boundary regions effectively.Further-more,a boundary guidance module is developed to direct the network in fusing the features obtained from the downs-ampled network output with the boundary region features,which have been enhanced to contain more refined posi-tional and structural information.A local channel attention mechanism is integrated into this module to identify critical channels.Finally,experiments conducted on the tracking dataset show that the proposed RP-Net achieves high posi-tioning accuracy and demonstrates strong adaptability in complex scenarios. 展开更多
关键词 rail positioning label generation boundary guidance oriented object detection
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Research on the Integration Path of Practical Teaching and Education in Civil Engineering and Transportation Majors Oriented by Employment
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作者 Lei Zou Lixin Li 《Journal of World Architecture》 2025年第3期29-35,共7页
To promote the achievement of high-quality and full employment goals for students in higher education,this paper analyzes the integration path of practical education and teaching in civil engineering and transportatio... To promote the achievement of high-quality and full employment goals for students in higher education,this paper analyzes the integration path of practical education and teaching in civil engineering and transportation majors,guided by surveying employment.This paper proposes three integration paths for practical teaching and education in civil engineering and transportation majors under the employment orientation.The first path is to create a modularized and informatized curriculum system.The second path is to deepen diverse cooperative practices between schools and enterprises.The third path is to construct a diversified quality evaluation system for academic achievement.To ensure the quality of education and employment,schools should continuously evaluate and reflect on the practical effects of these three paths to further optimize them. 展开更多
关键词 Civil engineering and transportation major Employment orientation SURVEYING Practical teaching
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Design of efficient microstructured path by magnetic orientation boron nitride nanosheets/MnFe_(2)O_(4) enabling waterborne polyurethane with high thermal conductivity and flame retardancy
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作者 Hao Jiang Jindao Li +6 位作者 Yuhui Xie Hua Guo Mukun He Xuetao Shi Yi Mei Xinxin Sheng Delong Xie 《Journal of Materials Science & Technology》 2025年第6期207-218,共12页
The miniaturization and high-power density of electronic devices presents new challenges in thermal management.The precise control of microstructure arrangement,particularly in boron nitride nanosheets(BNNS),is essent... The miniaturization and high-power density of electronic devices presents new challenges in thermal management.The precise control of microstructure arrangement,particularly in boron nitride nanosheets(BNNS),is essential for achieving efficient heat dissipation in highly thermally conductive composites within electrically insulating package.In this work,manganese ferrite was hydrothermally synthesized on BNNS,creating a layered structure in a magnetically responsive nanohybrid material named BNNS@M.This material was then integrated into a waterborne polyurethane(WPU)solution and shaped under a magnetic field to produce thermally conductive film.By altering the magnetic field direction,the mi-crostructure orientation of BNNS@M was controlled,resulting in anisotropic thermally conductive com-posite films with horizontal and vertical orientations.Specifically,under a vertical magnetic field,the film 30-Ve-BNNS@WPU,containing 30 wt.%BNNS@M,achieved a through-plane thermal conductivity of 8.5 W m^(−1)K^(−1)and an in-plane thermal conductivity of 1.8 W m^(−1)K^(−1),showcasing significant anisotropic thermal conductivity.Meanwhile,these films demonstrated excellent thermal stability,mechanical per-formance,and flame retardancy.Furthermore,employing Foygel’s theory elucidated the impact of filler arrangement on thermal conductivity mechanisms and the actual application of 5 G device chips and LED lamps emphasizing the potential of these thermally conductive films in thermal management appli-cations.This investigation contributes valuable design concepts and foundations for the development of anisotropic thermally conductive composites suitable for electron thermal management. 展开更多
关键词 Magnetic response Boron nitride nanosheets orientation arrangement Thermal conductivity Flame retardancy
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Analysis of Power Marketing Strategies for Market-Oriented Thermal Power Enterprises
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作者 Weiyu Wang 《Journal of Electronic Research and Application》 2025年第1期67-73,共7页
For thermal power enterprises,the traditional business model of scale expansion and a single product line restricts the development of electricity marketing.Therefore,to achieve the transformation and upgrading of the... For thermal power enterprises,the traditional business model of scale expansion and a single product line restricts the development of electricity marketing.Therefore,to achieve the transformation and upgrading of their electricity marketing,this study starts from the current situation of the electricity market and introduces in detail the market-oriented electricity marketing strategies of thermal power enterprises from four aspects:product strategy,price strategy,channel strategy,and promotion strategy.The analysis finds that a market-oriented electricity marketing strategy is not only an inevitable choice for thermal power enterprises to respond to current challenges but also an essential path for them to move toward high-quality development.Through continuous innovation and upgrading,thermal power enterprises will maintain a leading position in fierce market competition,achieve sustainable development,and make greater contributions to the prosperity and development of the energy industry. 展开更多
关键词 Market orientation Thermal power Electricity marketing
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Oriented Zn(002)planar plating/stripping for high-capacity ultralong-life aqueous batteries
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作者 Yuxiao Wang Weihua Tang 《Journal of Energy Chemistry》 2025年第10期89-99,共11页
Aqueous zinc-ion batteries(AZIBs)are facing the challenges of low stability of Zn anodes with dendrite growth and hydrogen evolution reaction in promoting commercial applications.We report herein a dualconfiguration b... Aqueous zinc-ion batteries(AZIBs)are facing the challenges of low stability of Zn anodes with dendrite growth and hydrogen evolution reaction in promoting commercial applications.We report herein a dualconfiguration bifunctional DL-citrulline(DL-Cit)as an electrolyte additive to stabilize Zn anodes for ultralong cycle-life aqueous energy storage.Trace amounts of DL-Cit reconstruct the solvation structure of Zn^(2+)via strong interactions with Zn^(2+),while DL-Cit is preferentially adsorbed on Zn anode surfaces to orchestrate the ion flux and ensure uniform Zn deposition.The well-formed flat Zn(002)texture not only enhances the electrochemical stability of Zn anodes but also exhibits more significant orientation priority upon increasing current density.These properties endow Zn anodes with an average coulombic efficiency of 99.7% after 1500 cycles and a long cycle life of over 3000 h,achieving an ultrahigh cumulative plating capacity of 4.8 Ah cm^(-2)even under rigorous plating/stripping conditions(8 mA cm^(-2)).Consequently,the Zn||MnO_(2)full cells provide a high capacity of 143.35 mA h g-1after continuous cycling for more than3000 cycles.The Zn||activated carbon hybrid capacitors with DL-Cit additives operate stably beyond30,000 cycles.This versatile electrolyte strategy provides an effective solution for the practical application of Zn-based energy storage devices. 展开更多
关键词 Amino acid additives Preferred orientation Aqueous zinc-ion batteries Interface chemistry Zinc anode
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