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Tangling and instability effect analysis of initial in-plane/out-of-plane angles on electrodynamic tether deployment under gravity gradient 被引量:1
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作者 Jing CUI Tao SHEN +1 位作者 Tao WEI Zhongyi CHU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第1期1-9,共9页
The space debris occupies the orbit resources greatly,which seriously threats the safety of spacecraft for its high risks of collisions.Many theories about space debris removal have been put forward in recent years.Th... The space debris occupies the orbit resources greatly,which seriously threats the safety of spacecraft for its high risks of collisions.Many theories about space debris removal have been put forward in recent years.The Electro Dynamic Tether(EDT),which can be deployed under gravity gradient,is considered to be an effective method to remove debris in low orbit for its low power consumption.However,in order to generate sufficient Lorentz force,the EDT needs to be deployed to several kilometers,which increases the risks of tangling and the instability of the EDT system.In the deployment process,different initial in-plane/out-of-plane angles,caused by direction error at initial release or the initial selection of ejection,affect the motion of EDT system seriously.In order to solve these problems,firstly,this paper establishes the dynamic model of the EDT system.Then,based on the model,safety metrics of avoiding tangling and assessing system stability during EDT deployment stage are designed to quantitatively evaluate the EDT system security.Finally,several numerical simulations are established to determine the safety ranges of the initial in-plane/out-of-plane angles on the EDT deployment. 展开更多
关键词 Assembly the electrodynamics tether system Electrodynamics tether deployment In-plane/out-of-plane angles Tangling risks
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Precise calibration of liquid crystal variable retarder for various incident angles
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作者 KONG Quan-hui-zi ZHANG Rui +2 位作者 XUE Peng WANG Zhi-bin JING Ning 《中国光学(中英文)》 北大核心 2026年第2期434-444,共11页
This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with ... This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with particular emphasis on the influence of different two-dimensional incident angles on phase delay behavior.Building upon the calibration of phase delay under normal incidence,a phase delay calibra-tion model was developed to account for variations in incident angle and driving voltage.A mathematical re-lationship was established between phase delay and the azimuth angle(α)and pitch angle(β).Experimental validation was conducted under three conditions:α=20°,β=0°;α=0°,β=20°;and an arbitrary angle whereα=5°,β=15°.The results demonstrated that the maximum average deviation between theoretical pre-dictions and experimental measurements did not exceed 0.059 rad.The proposed calibration method proved to be both accurate and practical.This approach offers robust support for LCVR parameter calibration and performance optimization in optical systems,particularly in polarization imaging applications. 展开更多
关键词 liquid crystal variable retarder(LCVR) two-dimensional incident angles drive voltage phase delay calibration
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Angling of hybrid sunfish from a hatchery pond with potential implications for community fisheries
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作者 Brian G.Blackwell Matthew J.Ward Todd M.Kaufman 《Aquaculture and Fisheries》 CSCD 2023年第1期91-95,共5页
Hatcheries are frequently called upon to produce catchable-sized fish for stocking community fishing ponds.Desirable attributes of fish selected for stocking into community ponds are that they are easy to produce in a... Hatcheries are frequently called upon to produce catchable-sized fish for stocking community fishing ponds.Desirable attributes of fish selected for stocking into community ponds are that they are easy to produce in a hatchery system to sizes anglers are interested in catching and they provide anglers with high catch rates once stocked.Hybrid sunfish[male Bluegill(Lepomis macrochirus)×female Green Sunfish(L.cyanellus)]have attributes that potentially make them attractive for use in community fishing ponds.We assessed initial angler catch rates of 100 stocked hybrid sunfish in a 0.12-ha hatchery pond and after being subjected to angling(four,1-hr catch-and-release fishing events with five anglers).We also investigated whether catch rates would change following a supplemental stocking of an additional 100 hybrid sunfish(four,1-hr catch-and-release fishing events with five anglers).The anal fin of each fish in the second stocking was hole punched to differentiate them from those of the first stocking and fish caught by anglers were hole punched in the caudal fin each time they were caught before being released back into the pond.Angler catch rates were highest during initial fishing events that followed stocking(9.2 fish/angler hr and 18.0 fish/angler hr)and substantially declined in subsequent events(≤3.4 fish/angler hr).Catches of the newly stocked fish and previously stocked fish contributed to the high catch following the supplemental stocking.Most(80%)of the fish were caught in the first 30 min of each event and 45%were caught during the first 10 min.Anglers were able to catch 88%of the fish from the first stocking and 67%from the second stocking at least once.No mortality occurred during the study as all fish were recovered when the pond was drained.Our results suggest that hybrid sunfish will potentially provide high initial catch rates following stocking into community ponds,but managers should expect reduced catch rates following initial fishing even without harvest.Additional stocking will be needed to provide periodic increases in angler catch rates even without harvest. 展开更多
关键词 Hybrid sunfish angling Community fishing ponds
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The auxin response factor OsARF12 modulates rice leaf angle via affecting shoot gravitropism Author links open overlay panel
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作者 Fengjun Xian Shuya Liu +7 位作者 Bin Xie Jishuai Huang Qiannan Zhang Yimeng Xu Xinrong Zhang Chen Lv Lin Zhu Jun Hu 《Journal of Genetics and Genomics》 2026年第2期234-245,共12页
Leaf angle is a pivotal agronomic trait that significantly influences crop architecture and yield.Plant hormones,such as auxin,play a critical role in regulating leaf angle;however,the underlying molecular mechanisms ... Leaf angle is a pivotal agronomic trait that significantly influences crop architecture and yield.Plant hormones,such as auxin,play a critical role in regulating leaf angle;however,the underlying molecular mechanisms remain to be fully elucidated.Here,we reveal that the auxin response factor gene,OsARF12,which is highly expressed in the leaf lamina joint,negatively regulates rice(Oryza sativa L.)leaf angle via affecting shoot gravitropism.Overexpression lines of OsARF12 exhibit more erect leaf angles,while the osarf12 mutants display enlarged leaf angles compared to the wild type.Further studies demonstrate that OsARF12 directly activates the expression of Loose Plant Architecture1(LPA1)and LAZY1 by binding to their promoters.The osarf12 mutant presents impaired shoot gravitropism,a phenotype consistent with that of the lpa1 and lazy1 mutants.Collectively,we elucidate the biological functions of OsARF12,which modulates leaf angle through its impact on shoot gravitropism by regulating the expression levels of LPA1 and LAZY1.This study provides insight into the role of auxin in determining rice leaf angle,potentially holding profound effects for the optimization of crop architecture. 展开更多
关键词 Rice Plant architecture Leaf angle Shoot gravitropism OsARF12
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Research on Reactive Power Control Strategy for Small Extinction Angle Operation of Hybrid Commutation Converters
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作者 Jiaxing Ning Xiaoguang Wei +3 位作者 Zhichang Yuan Longlong Chen Hui Du Zhanqing Yu 《Protection and Control of Modern Power Systems》 2026年第1期26-39,共14页
Hybrid commutation converters(HCCs)utilizing reverse-blocking integrated gate commutation thyristors(IGCTs)have gained significant attention due to their immunity to commutation failure.Leveraging the recovery enhance... Hybrid commutation converters(HCCs)utilizing reverse-blocking integrated gate commutation thyristors(IGCTs)have gained significant attention due to their immunity to commutation failure.Leveraging the recovery enhancement characteristics of IGCTs,HCCs demonstrate superior performance at reduced extinction angles,thereby minimizing reactive power consumption.This study presents a comprehensive investigation into reactive power control strategies for HCCs operating at small extinction angles.First,the topological configuration and commutation principle of HCC are elucidated.Subsequently,the mechanism of HCC reactive power control is analyzed,and a reactive power control strategy is proposed by combining the converter transformer taps with extinction angles.Moreover,the relationship between transformer taps and reactive power exchange under different rated extinction angles is calculated,and the theoretically rated extinction angle is proposed.Finally,to validate the proposed control strategy,a four-terminal ultra-high voltage direct current power grid incorporating HCC technology is modeled and sim-ulated using PSCAD/EMTDC.The simulation results demonstrate that the proposed strategy effectively supports AC systems by reducing reactive power absorption in HCCs,while simultaneously exhibiting enhanced reli-ability and economic efficiency. 展开更多
关键词 Commutation failure extinction angle HCC reactive power tap position
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Experimental and numerical investigation of incident angle effects on the dynamic response of RC beams under near-field blast loading
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作者 Zhijie Zhang Qiushi Yan +4 位作者 Weihao Liang Chenxu Lyu Naixin Zuo Minghui Hong Dongdong Zhao 《Defence Technology(防务技术)》 2026年第3期166-182,共17页
Reinforced concrete(RC)beams face potential near-field blast threats as key structural components in building structures.To investigate the failure modes and dynamic responses of RC beams subjected to near-field blast... Reinforced concrete(RC)beams face potential near-field blast threats as key structural components in building structures.To investigate the failure modes and dynamic responses of RC beams subjected to near-field blast loading,this paper presents both blast tests and numerical simulation studies on RC beams.First,near-field blast tests were conducted on five RC beam specimens under strong and weak-axis bending loading.Then,a refined finite element model of RC beams was established to verify the applicability of the adopted finite element analysis method.Finally,based on the calibrated finite element model,the failure mechanisms of RC beams were explored,and the influence of blast incidence angle on the failure modes and dynamic responses of RC beams was investigated.The results indicate:(i)Near-field blast loading demonstrates pronounced non-uniform distribution patterns.Under strong-axis incidence,clearing effects beyond the mid-span region are more significant than weak-axis incidence,leading to accelerated impulse attenuation.(ii)Three consecutive developmental stages primarily control the damage mechanism of RC beams:stress wave-induced local damage,local deformation causing plastic hinge propagation,and free vibration of the beam;(iii)As the scaled distance decreases,the failure mode of RC beams under weak-axis blast loading evolves from flexural failure to local failure.The resistance mechanism of RC beams under weak-axis blast loading is more prone to transition from compressive membrane action to tensile membrane action,reducing their blast resistance capacity;(iv)As the explosion incident angleθincreases from 0°to 90°,the blast wave-structure interaction transitions from regular reflection to Mach reflection and back to normal reflection,causing the dynamic response of RC beams to first decrease then increase,with corner concrete spalling damage being the primary failure mode. 展开更多
关键词 Rc beam Blast tests Near-field blast Incident angle Damage mechanism
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Ultrasound biomicroscopy analysis of age-related trends in lens stability in cortical cataracts
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作者 Jia-Jun Chen Ling Wang +3 位作者 Sha-Sha Xue Zhi-Ying Yu Yun-Xiao Wang Feng-Lei Wang 《International Journal of Ophthalmology(English edition)》 2026年第2期252-259,共8页
AIM:To investigate age-related differences in the irislens angle(ILA)among patients with age-related cortical cataracts and elucidate the impact of age on lens stability.METHODS:A prospective observational study was c... AIM:To investigate age-related differences in the irislens angle(ILA)among patients with age-related cortical cataracts and elucidate the impact of age on lens stability.METHODS:A prospective observational study was conducted on patients with age-related cortical cataracts scheduled for phacoemulsification surgery.Preoperative ultrasound biomicroscopy(UBM)images were collected and analyzed.Initially,patients were stratified into two age groups:<60y and≥60y,with no significant intergroup differences in sex or eye laterality.For further analysis,participants were subdivided into three age strata:<60y,60-75y,and>75y.The ILA was measured in four quadrants(superior,inferior,nasal,and temporal).Intergroup differences in ILA were compared,and correlations between age and ILA parameters were analyzed using statistical methods.RESULTS:The sample data were categorized into three groups according to age,<60y(113 patients;55.8%female),60–75y(245 patients;61.0%female),and>75y(70 patients;50.2%female).The superior quadrant ILA increased progressively with age stratification(P=0.02),and the maximum ILA difference(ΔILA)was significantly higher in patients over 75y(P<0.01).Simple linear regression analysis demonstrated a positive correlation between age and ILA in the superior(Y=7.487+0.096X,R=0.191,P<0.001)and temporal(Y=10.254+0.052X,R=0.104,P=0.032)quadrants.Additionally,the mean ILA across all quadrants(ILAmean)andΔILA were positively correlated with age(ILAmean:Y=9.721+0.055X,R=0.138,P=0.004;ΔILA:Y=3.267+0.044X,R=0.006,P<0.05).CONCLUSION:In patients with age-related cortical cataracts,ILA increases with age,particularly in the superior and temporal quadrants,suggesting that advanced age is associated with greater lens deviation and decreased lens stability.UBM imaging can effectively evaluate the status of the zonule and lens stability,providing crucial evidence for personalized surgical planning based on patients’age. 展开更多
关键词 iris-lens angle age-related cortical cataract lens stability ultrasound biomicroscopy PHACOEMULSIFICATION surgical planning
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Effect of Spudcan Penetration Angles on Adjacent Bucket Foundation in Sand
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作者 Conghuan Le Zhenqi He +2 位作者 Hao Hu Puyang Zhang Hongyan Ding 《哈尔滨工程大学学报(英文版)》 2026年第1期95-109,共15页
Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket... Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket and surrounding soil.During the seabed penetration of a spudcan from a jack-up wind turbine installation vessel,an angle may form between the spudcan’s axis and the axis of symmetry of the adjacent composite bucket foundation in the horizontal plane.Such a misalignment may affect load distribution and the non-uniform interaction between the foundation,soil,and spudcan,ultimately influencing the foundation’s stability.This study employs physical model tests to ascertain the trends in end resistance during spudcan penetration in sand,the extent of soil disturbance,and the backflow condition.The finite element coupled Eulerian-Lagrangian method is validated and utilized to determine the range of penetration angles that induce alterations in the maximum vertical displacement and tilt rate of the composite bucket foundation in sand.The differential contact stress distribution at the base of the bucket is analyzed,with qualitative criteria for sand backflow provided.Findings demonstrate that the maximum vertical displacement and tilt rate of the composite bucket foundation display a“wave-like”variation with the increasing spudcan penetration angle,peaking when the angle between the spudcan and bulkhead is the smallest.Stress distribution is predominantly concentrated at the base and apex of the bucket,becoming increasingly uneven as the penetration angle deviates from the foundation’s symmetry axis.The maximum stress gradually shifts to the junction of the bulkhead and bucket bottom on the side with the shortest net distance from the spudcan.Considering the in-place stability and stress state of the composite bucket foundation is therefore imperative,and particular attention should be paid to the foundation’s state when the angle between the spudcan and bulkhead is small. 展开更多
关键词 Spudcan penetration Soil disturbance Penetration angle Composite bucket foundation Coupled Eulerian-Lagrangian
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Characterization of rockfalls in Cappadocia region(Türkiye)by empirical and 3-Dimensional methods
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作者 Ogün Ozan VAROL Mutluhan AKIN +1 位作者 İsmail DINÇER Ahmet ORHAN 《Journal of Mountain Science》 2026年第1期203-220,共18页
Rockfall hazards pose significant risks to both cultural heritage and populated areas,necessitating comprehensive assessment methodologies.Despite extensive research on rockfalls,only a small number of studies have di... Rockfall hazards pose significant risks to both cultural heritage and populated areas,necessitating comprehensive assessment methodologies.Despite extensive research on rockfalls,only a small number of studies have directly compared empirical methods with modelling approaches.This study investigated rockfalls in five settlements within the Cappadocia region of Türkiye,employing both empirical methods and advanced three-dimensional(3D)probabilistic modeling.The energy line angle approach was applied to identify rockfall propagation zones,while high-resolution digital surface models derived from unmanned aerial vehicle(UAV)imagery facilitated detailed 3D rockfall simulations.Cappadocia’s unique geological setting—comprising alternating layers of ignimbrites and weaker fluviolacustrine deposits—renders it highly susceptible to rockfalls intensified by wetting-drying and freeze-thaw cycles.Results indicate that rockfall propagation characteristics vary markedly between settlements:Göre and Tatlarin exhibit shorter runout distances due to basalt-dominated slopes,whereas Akköy,SoğanlıandŞahinefendi display longer trajectories associated with welded ignimbrites.Empirical cone propagation analyses correspond broadly with field observations,but variations in energy line angles(23°-33°)highlight the necessity for site-specific calibration.Comparative evaluations demonstrate that 3D probabilistic modeling better captures local-scale block dynamics and identifies high-risk areas affected by topographic and structural features such as rockfall ditches.These findings emphasize the importance of integrating empirical and 3D approaches to improve hazard zoning,optimize mitigation structures and guide the protection of Cappadocia’s unique cultural heritage landscape. 展开更多
关键词 ROCKFALL 3D probabilistic modeling Empirical analysis Energy line angle Cultural heritage
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Approach angle constrained and varying speed cooperative guidance against maneuvering targets
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作者 Xiangjun Ding Jianan Wang +1 位作者 Junhui Liu Jiayuan Shan 《Defence Technology(防务技术)》 2026年第3期56-70,共15页
This paper addresses the three-dimensional(3-D)approach angle constrained cooperative guidance problem for speed-varying missiles against maneuvering targets.First,the guidance problem is formulated in a relative refe... This paper addresses the three-dimensional(3-D)approach angle constrained cooperative guidance problem for speed-varying missiles against maneuvering targets.First,the guidance problem is formulated in a relative reference frame and a virtual control input is selected.Then,the cooperative guidance law is designed on the basis of a prediction-correction framework.The time-to-go under the baseline command is estimated by an efficient prediction method with a realistic aerodynamic model and a biased command is developed by utilizing the time-to-go predictions for synchronizing different missiles'impact times.The design of the biased command is decoupled into the individual design of its direction and magnitude.It is proved that the designed cooperative guidance law can make the time-to-go consensus error converge to zero before interception.Finally,the designed guidance law is validated through a series of numerical simulations. 展开更多
关键词 Cooperative guidance Maneuvering target Time-varying speed Approach angle constraint
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Hysteresis behavior of RC columns with steel angle ends under various levels of axial load
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作者 Zhan Bixiong Geng Xiangri Zhou Wei 《Earthquake Engineering and Engineering Vibration》 2026年第1期157-170,共14页
Bolting steel angles at the bottom ends of columns provides a rapid and efficient method for repairing damaged structures,while also offering a viable approach to restore their potential bearing capacity.To validate t... Bolting steel angles at the bottom ends of columns provides a rapid and efficient method for repairing damaged structures,while also offering a viable approach to restore their potential bearing capacity.To validate the suitability of specific strengthening strategies,particularly the utilization of bolted steel angles,three reinforced concrete frame specimens were subjected to hysteresis testing.These specimens all featured RC columns strengthened with steel angle ends.Additionally,one control specimen without steel angle ends was included in the testing.The hysteresis effects of bolting steel angles were discussed in terms of typical failure mode,hysteresis and skeleton curves,stiffness degradation and energy dissipation.The experimental results revealed that the three specimens that had bolted steel angles exhibited ductile failure behavior.Through analysis of hysteresis and skeleton curves,it was observed that the frame demonstrated distinct plasticity,maintaining sufficient load-bearing capacity even after yielding and exhibiting superior displacement ductility performance.Considering equivalent viscous damping,the energy dissipation capacity of the RC frame increased linearly with drift and remained largely unaffected by structural damage.Therefore,bolting steel angles at specified cross-sections proved to be a viable technique for structural repair and restoration. 展开更多
关键词 reinforced concrete column steel angle ends hysteresis response stiffness degradation energy dissipation
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Influence of joint angles and in-situ stress on blasting effects in layered rock mass
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作者 YU Jianxin FENG Yingtao +3 位作者 WEN Jinhao ZHANG Hao WEN Zhijie LI Zhenzhen 《Journal of Mountain Science》 2026年第2期857-868,共12页
Drilling and blasting in layered rock masses faces significant challenges,as pre-existing joints cause unbalanced energy distribution,leading to poor forming effects and severe over-excavation.However,a comprehensive ... Drilling and blasting in layered rock masses faces significant challenges,as pre-existing joints cause unbalanced energy distribution,leading to poor forming effects and severe over-excavation.However,a comprehensive understanding of the complex coupling mechanisms between key joint parameters and the in-situ stress field on the final blasting outcome is still lacking.The model tests are used to quantitatively analyze the macroscopic crushing characteristics and crack propagation velocity.The numerical simulation then reveals the underlying mechanisms of stress wave propagation and energy partitioning,which are validated against the experimental results.The results indicate that the joints and the in-situ stress field play distinct,competitive roles in the blasting outcome.First,the joints control the anisotropy of the damage:crack propagation is primarily guided along the joint direction(the channel effect),and the apparent crack velocity exhibits a V-shaped trend with the joint inclination angle(0°-90°).Second,the in-situ stress state controls the overall extent of the damage:Increased confining pressure(both equal and unequal)inhibits crack propagation by increasing the failure threshold of the rock mass.Mechanistically,while this locking effect enhances stress wave transmission(i.e.,reduces the locking effect),this is secondary to the dominant inhibitory effect of the increased overall rock mass strength.The primary contribution of this study is the identification of this dual control mechanism,revealing that the final blasting effect is a non-linear competition between the joint's structural guidance and the dominant strengthening effect from the in-situ stress field,which clarifies the complex energy partitioning mechanisms at the blast source. 展开更多
关键词 Layered rock mass Joint angle Confining pressure Crack propagation Blasting effect Stress wave propagation
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Effect of initial fracture angle on the failure pattern and gas flow channel of sandstone under multistage loading
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作者 Quanle Zou Feixiang Lv +4 位作者 Zihan Chen Qingsong Li Jianjun Zhao Qican Ran Qingmiao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期2142-2157,共16页
After coal seam mining,the overlying rock strata above the goaf are subjected to long-term stress and eventually undergo failure.Under mining-induced disturbances,the strata develop fractures at various angles,which s... After coal seam mining,the overlying rock strata above the goaf are subjected to long-term stress and eventually undergo failure.Under mining-induced disturbances,the strata develop fractures at various angles,which significantly influence failure modes and the morphology of gas flow channels.This study employed multistage loading experiments,numerical simulations,three-dimensional reconstruction,and image recognition to investigate the fragmentation process of rocks with different initial fracture angles under multistage loading.The results show that variations in the initial fracture angle affect the transmission of contact forces among rock particles.As the angle increases,the transmission pattern shifts from a uniform distribution to one extending along the direction of the fracture.Rocks with small initial fracture angles tend to experience tensile-dominated failure,with most of the material subjected to longitudinal loading,resulting in reduced strength.Fractures propagate from the central region of the initial fracture,producing a complex internal fracture network.The proportion of fracture channels varies considerably across regions,creating multiple zones of velocity variation in the gas flow.In contrast,rocks with large initial fracture angles are more susceptible to shear failure,with the primary load-bearing zones aligned along the inclined fracture direction.As a result,the influence on surrounding regions is limited,improving the rock's load-bearing capacity under multistage loading.In these cases,the distribution and proportion of fracture channels become more uniform,promoting more stable gas flow within the channels.Overall,these findings provide theoretical insights into how initial fracture angles govern rock failure patterns and gas flow characteristics. 展开更多
关键词 Multistage loading Initial fracture angle Failure pattern Gas flow characteristics Three-dimensional fracture reconstruction
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Diurnal Bias Correction of FY-4B AGRI Water Vapor Channels with Time-Shifted Solar Elevation Angle
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作者 SONG Jia-yun HAN Wei +1 位作者 SUN Hao-fei YANG Yun-fan 《Journal of Tropical Meteorology》 2026年第1期19-32,共14页
The infrared channels of the FY-4B advanced geosynchronous radiation imagers(AGRI) play a crucial role in temperature and humidity analyses for mesoscale numerical weather prediction, particularly in enhancing the ini... The infrared channels of the FY-4B advanced geosynchronous radiation imagers(AGRI) play a crucial role in temperature and humidity analyses for mesoscale numerical weather prediction, particularly in enhancing the initial field quality and the forecasting accuracy of the model. This study assimilated FY-4B AGRI data into the CMA-MESO model and analyzed the bias characteristics and correction methods. Analysis of the AGRI data revealed a clear diurnal variation in the bias, which was positively correlated with the solar elevation angle. However, the diurnal variation in the bias lagged behind the solar elevation angle, likely owing to temperature changes and delayed instrument responses resulting from solar radiation. To address this issue, we propose a correction method that utilizes the solar elevation angle after an optimal time shift. Using the time-shifted solar elevation angle as a predictor effectively reduces the diurnal variation in bias and significantly improves the correction effect. This approach provides theoretical support for the assimilation of FY-4B AGRI data into mesoscale numerical weather predictions, thereby enhancing the reliability of the assimilation results. 展开更多
关键词 FY-4B AGRI bias correction diurnal variation solar elevation angle
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Deep Learning in Electromyography Signal-based Lower Limb Angle Prediction and Activity Classification
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作者 Gundala Jhansi Rani Mohammad Farukh Hashmi 《Journal of Bionic Engineering》 2026年第1期274-290,共17页
This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamline... This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamlines the research on the lower limb activities.The HILLAR model includes Discrete Hermite Wavelets Transform-based Synchrosqueezing(DHWTS),Deep Two-Layer Multiscale Convolutional Neural Network(DTLMCNN),and Generalized Regression Neural Network(GRNN)as feature extraction,activity recognition,and knee angle prediction respectively.Electromyography signal-based automatic lower limb activity detection is crucial to rehabilitation and human movement analysis.Yet several of these methods face issues in feature extraction in complex data,overlapping signals,extraction of crucial parameters,and adaptation constraints.This research aims classify lower limb activities and predict knee joint angles from electromy-ography signals using HILLAR model.The model is validated on two datasets,comprising 26 subjects performing three classes of activities:walking,standing,and sitting.The proposed model obtained a classification accuracy of 99.95%,along with significant achievements in precision(99.93%),recall(99.91%),and F1-score(99.93%).The generalized regression neural network predicted angles of the knee joint with a root mean squared error of 1.25%.Robustness is demonstrated through consistent results in five-fold cross-validation and statistical significance testing(p-value=0.004,McNemar's test).Additionally,the proposed model showed superior performance over baseline methods by reducing error rates by 18%and decreasing processing time to 0.98 s. 展开更多
关键词 ELECTROMYOGRAPHY Lower limb motion recognition Knee joint angle prediction Convolutional neural network Wavelet transform
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Long-term outcomes following lens extraction surgery in acute primary angle closure
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作者 Yi-Ning Guo Jing Ding +3 位作者 Hao-Ran Ai Xin-Zuo Zhou Xue-Min Li Chun Zhang 《International Journal of Ophthalmology(English edition)》 2026年第2期281-290,共10页
AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longit... AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longitudinal observational study,detailed medical histories of APAC patients and comprehensive ophthalmic examinations at final followup were collected.Logistic regression analysis was performed to identify predictors of blindness.Univariate and multivariate linear regression analyses were conducted to determine risk factors associated with visual outcomes.RESULTS:This study included 39 affected eyes of 31 subjects(26 females)with an average age of 74.1±8.0y.At 6.7±4.2y after APAC attack,2(5.7%)eyes had bestcorrected visual acuity(VA)worse than 3/60.Advanced glaucomatous visual field loss was observed in 15(39.5%)affected eyes and 5(25.0%)fellow eyes.Nine affected eyes(23.7%)had GON,and 11(28.9%)were blind.Six(15.4%)affected eyes and 2(9.1%)fellow eyes had suspicious progression.A significantly higher blindness rate in factory workers compared to office workers.Logistic regression identified that worse VA at attack(OR 10.568,95%CI 1.288-86.695;P=0.028)and worse early postoperative VA(OR 13.214,95%CI 1.157-150.881;P=0.038)were risk factors for blindness.Multivariate regression showed that longer duration of elevated intraocular pressure(P=0.004)and worse early postoperative VA(P=0.009)were associated with worse visual outcomes.CONCLUSION:Despite LE surgery,some APAC patients experience continued visual function deterioration.Lifelong monitoring is necessary.Target pressure and progression rates should be re-evaluated during follow-up. 展开更多
关键词 acute primary angle closure lens extraction surgery long-term follow-up visual impairment glaucomatous optic neuropathy
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Large contact angle hysteresis enhances post-impact droplet oscillations
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作者 Pengfei Zhao Sai Raja Gopal Vadlamudi +5 位作者 Mi Zhou Binyu Zhao Jiu Huang Günter K.Auernhammer Uwe Hampel Wei Ding 《Droplet》 2026年第1期106-113,共8页
Droplet impact on solid surfaces plays a critical role in a wide range of applications,including inkjet printing,spray cooling,surface coatings,and microdroplet chemistry.Precise control of droplet–surface interactio... Droplet impact on solid surfaces plays a critical role in a wide range of applications,including inkjet printing,spray cooling,surface coatings,and microdroplet chemistry.Precise control of droplet–surface interactions is essential,but the fundamental mechanisms governing this process are still not fully understood.In this study,we demonstrate that large contact angle hysteresis(CAH)on hydrophobic nanoporous surfaces significantly amplifies post-impact droplet oscillations.This reveals the critical influence of CAH on the redistribution of impact energy and the modulation of droplet–surface interactions.Using shape mode decomposition via Legendre polynomials and fast Fourier transform spectral analysis,we show that surfaces with larger CAH excite and sustain higher-order droplet shape mode oscillations,leading to persistent capillary waves even after contact line pinning.The observed amplitude modulation and multiple frequency components within individual shape modes reveal nonlinear energy transfer between different modes.These amplified and coupled oscillations are shown to promote daughter droplet coalescence.This study presents a framework for understanding the role of CAH in storing and redistributing impact energy through nonlinear mode excitation and establishes CAH as a critical design parameter for controlling fluid dynamics on solid surfaces. 展开更多
关键词 microdroplet chemistryprecise droplet impact energy redistribution hydrophobic nanoporous surfaces contact angle hysteresis solid surfaces inkjet printingspray coolingsurface OSCILLATIONS
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GranuSAS:Software of rapid particle size distribution analysis from small angle scattering data
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作者 Qiaoyu Guo Fei Xie +3 位作者 Xuefei Feng Zhe Sun Changda Wang Xuechen Jiao 《Chinese Physics B》 2026年第2期216-225,共10页
Small angle x-ray scattering(SAXS)is an advanced technique for characterizing the particle size distribution(PSD)of nanoparticles.However,the ill-posed nature of inverse problems in SAXS data analysis often reduces th... Small angle x-ray scattering(SAXS)is an advanced technique for characterizing the particle size distribution(PSD)of nanoparticles.However,the ill-posed nature of inverse problems in SAXS data analysis often reduces the accuracy of conventional methods.This article proposes a user-friendly software for PSD analysis,GranuSAS,which employs an algorithm that integrates truncated singular value decomposition(TSVD)with the Chahine method.This approach employs TSVD for data preprocessing,generating a set of initial solutions with noise suppression.A high-quality initial solution is subsequently selected via the L-curve method.This selected candidate solution is then iteratively refined by the Chahine algorithm,enforcing constraints such as non-negativity and improving physical interpretability.Most importantly,GranuSAS employs a parallel architecture that simultaneously yields inversion results from multiple shape models and,by evaluating the accuracy of each model's reconstructed scattering curve,offers a suggestion for model selection in material systems.To systematically validate the accuracy and efficiency of the software,verification was performed using both simulated and experimental datasets.The results demonstrate that the proposed software delivers both satisfactory accuracy and reliable computational efficiency.It provides an easy-to-use and reliable tool for researchers in materials science,helping them fully exploit the potential of SAXS in nanoparticle characterization. 展开更多
关键词 small angle x-ray scattering data analysis software particle size distribution inverse problem
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Theoretical investigation on the initiation and propagation behavior of dominant cracks in valley slopes
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作者 Xianlun Leng Chuan Wang +4 位作者 Chengtang Wang Zhanrong Zhang Haibin Wang Lan Cui Kun Fang 《International Journal of Mining Science and Technology》 2026年第1期95-112,共18页
The stability of rock slopes is frequently controlled by the initiation and propagation of inherent dominant cracks.This study systematically investigated these processes in valley slopes by combining fracture-mechani... The stability of rock slopes is frequently controlled by the initiation and propagation of inherent dominant cracks.This study systematically investigated these processes in valley slopes by combining fracture-mechanics analysis with transparent soil model tests.An analytical expression for the stress field at the dominant crack tip was derived from the slope stress distribution by superposing the corresponding stress intensity factors(SIFs).The theoretical predictions were then validated against observations from transparent soil model tests.The influences of slope angle(β),crack inclination angle(α),crack position parameter(b),and crack length parameter(h)on crack initiation and propagation were quantified.The results indicated that:(1)cracks at the slope crest tended to propagate in shear mode,and the shear crack initiation angle(θ_(s))was approximately 8°.Cracks at the slope toe might propagate in either tensile or shear mode.(2)θ_(s) at the slope crest increased withβ,b,and l,and decreased withα.The maximum change inθ_(s) induced by the considered parameters was approximately 30°.(3)The tensile crack initiation angle(θ_(t))at the slop toe decreased withβ,α,and l,while the influence of b was comparatively minor.The maximum change inθ_(t) caused by individual parameters ranged approximately from 25°to 60°.Predicted crack propagation modes and directions showed good agreement with experimental results.These findings provide theoretical guidance for stability assessments of valley slopes controlled by dominant crack propagation. 展开更多
关键词 Valley rock slope Crack initiation angle Crack propagation mode Stress field formula Fracture mechanics
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Battery SOH enhanced solution:Voltage reconstruction and image recognition response to loss of data scenarios
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作者 Xinghua Liu Linxiang Zhou +4 位作者 Jiaqiang Tian Longxing Wu Zhongbao Wei Hany M.Hasanien Peng Wang 《Journal of Energy Chemistry》 2026年第1期155-169,I0005,共16页
Accurate estimation of battery health status plays a crucial role in battery management systems.However,the lack of operational data still affects the accuracy of battery state of health(SOH)estimation.For this reason... Accurate estimation of battery health status plays a crucial role in battery management systems.However,the lack of operational data still affects the accuracy of battery state of health(SOH)estimation.For this reason,a SOH estimation method is proposed based on charging data reconstruction combined with image processing.The charging voltage data is used to train the least squares generative adversarial network(LSGAN),which is validated under different levels of missing data.From a visual perspective,the Gram angle field method is applied to convert one-dimensional time series data into image data.This method fully preserves the time series characteristics and nonlinear evolution patterns,which avoids the difficulties and limited expressive power associated with manual feature extraction.At the same time,the Swin Transformer model is introduced to extract global structures and local details from images,enabling better capture of sequence change trends.Combined with the long short-term memory network(LSTM),this enables accurate estimation of battery SOH.Two different types of batteries are used to validate the test.The experimental results show that the proposed method has good estimation accuracy under different training proportions. 展开更多
关键词 State of health Voltage data reconstruction Least squares generative adversarial NETWORK Gramicci angle field Swin Transformer-LSTM network
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