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Accurate simulation for strength-degrading effects of geomaterials via a decoupling approach to treating tension-compression asymmetry
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作者 Quanpu LIU Haonan HE +3 位作者 Siyu WANG Lin ZHAN O.BRUHNS Heng XIAO 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期283-302,共20页
This study focuses on a new and high-efficiency approach in a unified sense of accurately simulating strength-degrading effects for geomaterials,including non-symmetric hardening-to-softening effects in tension and co... This study focuses on a new and high-efficiency approach in a unified sense of accurately simulating strength-degrading effects for geomaterials,including non-symmetric hardening-to-softening effects in tension and compression as well as non-symmetric tensile and compressive stiffness-degrading effects during unloading.It is intended to bypass both modeling and numerical complexities involved in existing approaches.To this goal,new elastoplastic equations are established with new numerical techniques.With a decoupling technique of treating tension-compression asymmetry,the foregoing complex effects are automatically incorporated as inherent response features of the new elastoplastic equations,thus bypassing usual modeling complexities.A new numerical technique of renormalizing piecewise spline functions is introduced to resolve the central yet tough issue of obtaining accurate and unified expressions for the tensile and compressive strength functions,thus bypassing usual numerical complexities and uncertainties in treating numerous unknown parameters and multiple ad hoc criteria.As such,the new approach is not only of wide applicability for various geomaterials but also of high computational efficiency with no more than three adjustable parameters.Toward validating the efficacy of the new approach,numerical examples for granite,salt rock,and sandstone-concrete combined body as well as plain concrete,high-performance concrete,and ultrahigh-performance concrete are presented by comparing model predictions with multiple data sets for strength-degrading effects in tension and compression. 展开更多
关键词 geomaterial ELASTOPLASTIC tension-compression asymmetry HARDENING SOFTENING stiffness degradation decoupling technique high-efficiency scheme
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Periodical sparse-assisted decoupling method for local fault detection of spiral bevel gears
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作者 Keyuan LI Yanan WANG +2 位作者 Baijie QIAO Zhibin ZHAO Xuefeng CHEN 《Chinese Journal of Aeronautics》 2026年第1期349-369,共21页
Early fault detection for spiral bevel gears is crucial to ensure normal operation and prevent accidents.The harmonic components,excited by the time-varying mesh stiffness,always appear in measured vibration signal.Ho... Early fault detection for spiral bevel gears is crucial to ensure normal operation and prevent accidents.The harmonic components,excited by the time-varying mesh stiffness,always appear in measured vibration signal.How to extract the periodical impulses that indicate gear localized fault buried in the intensive noise and interfered by harmonics is a challenging task.In this paper,a novel Periodical Sparse-Assisted Decoupling(PSAD)method is proposed as an optimization problem to extract fault feature from noisy vibration signal.The PSAD method decouples the impulsive fault feature and harmonic components based on the sparse representation method.The sparsity within and across groups property and the periodicity of the fault feature are incorporated into the regularizer as the prior information.The nonconvex penalty is employed to highlight the sparsity of fault features.Meanwhile,the weight factor based on2norm of each group is constructed to strengthen the amplitude of fault feature.An iterative algorithm with Majorization-Minimization(MM)is derived to solve the optimization problem.Simulation study and experimental analysis confirm the performance of the proposed PSAD method in extracting and enhancing defect impulses from noisy signal.The suggested method surpasses other comparative methods in extracting and enhancing fault features. 展开更多
关键词 Fault detection Nonconvex optimization Sparse decoupling Sparsity within and across groups Spiral bevel gear
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Insights into material use and economic decoupling in China’s infrastructure for sustainable development
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作者 GUO Hongwei HAN Ji 《Regional Sustainability》 2025年第5期76-94,共19页
Quantifying material use in infrastructure development and analyzing its relationship with economic growth is essential for enhancing resource efficiency and steering regional resource management toward sustainable de... Quantifying material use in infrastructure development and analyzing its relationship with economic growth is essential for enhancing resource efficiency and steering regional resource management toward sustainable development.This study systematically assessed infrastructure related material use in 30 provinces,autonomous regions,and municipalities in China during 1978-2022.The result indicated that material stock has experienced significant growth,increasing from 16.91×10^(9)t in 1978 to 103.60×10^(9)t in 2022,with an average annual growth rate of 4.20%.However,from 1978 to 2015,material input followed a strong upward trend but saturated after 2015.At the national level,material input peaked in 2015,after which it began to decline.The central region reached its peak earlier in 2013,while the eastern and western regions peaked in 2015.Using a decoupling analysis framework,this study revealed that nationally,the elasticity value between material stock and gross domestic product(GDP)remained near or above 1.0,reflecting continued reliance on stock accumulation.Regionally,the elasticity value between material stock and GDP has increased in the central and western regions during 1978-2022,whereas elasticity value between material stock and GDP in the eastern region showed a slower growth rate but still struggled to achieve absolute decoupling.Moreover,the elasticity value between material input and GDP has declined at the national level,presenting a relative decoupling,with some regions already achieving absolute decoupling.The eastern region was closer to absolute decoupling,while the central and western regions,though still intensive in material input,exhibited faster declines in elasticity.Accelerating the transition from linear to circular economy is an essential step for China to achieve absolute decoupling and long-term sustainability.Finally,this research recommends promoting the adoption of renewable energy,driving industrial upgrading,implementing compact urban design,and extending the lifespan of infrastructure to reduce material dependency and achieve sustainable infrastructure transformation at the national level. 展开更多
关键词 Material stock Material input decoupling analysis framework Infrastructure lifespan Sustainable development Circular economy
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A Soft Tactile Unit with Three-Dimensional Force and Temperature Mathematical Decoupling Ability for Robots
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作者 Xiong Yang Hao Ren +11 位作者 Dong Guo Zhengrong Ling Tieshan Zhang Gen Li Yifeng Tang Haoxiang Zhao Jiale Wang Hongyuan Chang TszKi Gao Jia Dong Ningxin Wu Yajing Shen 《Engineering》 2025年第12期96-106,共11页
Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile ... Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile sensors,accurately decoupling signals—specifically separating forces from directional orientation and temperature—remains a challenge thus resulting in failure to meet the advanced application requirements of robots.This study proposes,F3T,a multilayer soft sensor unit designed to achieve isolated measurements and mathematical decoupling of normal pressure,omnidirectional tangential forces,and temperature.We developed a circular coaxial magnetic film featuring a floating mount multilayer capacitor that facilitated the physical decoupling of normal and tangential forces in all directions.Additionally,we incorporated an ion gel-based temperature-sensing film into the tactile sensor.The proposed sensor was resilient to external pressures and deformations,and could measure temperature and significantly eliminate capacitor errors induced by environmental temperature changes.In conclusion,our novel design allowed for the decoupled measurement of multiple signals,laying the foundation for advancements in high-level robotic motion control,autonomous decision-making,and task planning. 展开更多
关键词 Tactile sensor Force decoupling Temperature and force decoupling Robot-human interaction
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Decoupling combustion of coal briquettes and coal-biomass blends in a pilot-scale test facility for novel grate boilers
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作者 Xinhua Liu Bin Liang +1 位作者 Jian Han Shanwei Hu 《Chinese Journal of Chemical Engineering》 2025年第11期357-368,共12页
With the increasingly stringent national environmental protection policies,the ultra-low emission transformation of industrial coal-fired grate boilers and the highly efficient utilization of biomass resources or wast... With the increasingly stringent national environmental protection policies,the ultra-low emission transformation of industrial coal-fired grate boilers and the highly efficient utilization of biomass resources or wastes are becoming increasingly urgent in China.This study first proposes a novel and simple configuration for industrial grate boilers to integrate the decoupling combustion and flue gas recirculation or co-firing technologies,so as to reduce pollutant emission but improve thermal efficiency.Burning coal briquettes in the novel grate boiler,the original NO_(x) emissions can be remarkably decreased to as low as 56 mg· m^(-3),corresponding to the reduction efficiency of 82.8% in comparison with the average value in traditional coal-fired grate boilers.Co-firing coal briquettes with straw pellets in the novel grate boiler,the strongest synergistic effect of NO_(x) reduction is observed at the blending mass fraction of 50%,in which the NOxemissions can be further mitigated by at most 16.0% on top of the already reduced amount by decoupling combustion to reach less than about 165 mg· m^(-3).The novel grate boiler allows co-firing Chinese medicine residue with high water content at the blending mass fraction of up to 30% on the premise of low NO_(x) and CO emissions.All experimental results in this study demonstrated the obvious superiorities of the novel grate boiler in reducing NO_(x) and CO emissions and mitigating both slagging tendency and slag carbon content,which can be attributed to either the cumulative effects of decoupling combustion with flue gas recirculation or the synergistic effects of cofiring coal-biomass blends.The newly-developed travelling-grate decoupling combustion technology can be expected to provide an economical and convenient measure for the ultra-low NO_(x) emission transformation of industrial coal-fired grate boilers as well as the clean and highly efficient consumption of biomass wastes with high water content or difficulty to burn in China. 展开更多
关键词 decoupling combustion NO_(x)emission Coal briquette Straw pellet Medicine residue Grate boiler
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Decoupling and Driving Forces in Economic Growth,Energy Consumption,and Carbon Emissions:Evidence from China’s BTH Region
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作者 Hao Yue Di Gao +3 位作者 Jin Gao Chengmei Wei Jiali Duan Shaocheng Mei 《Energy Engineering》 2025年第12期5091-5109,共19页
Against the backdrop of regional coordinated development and China’s“dual carbon”strategic objectives,the Beijing-Tianjin-Hebei(BTH)region faces an urgent need to transition fromits traditional economic growth mode... Against the backdrop of regional coordinated development and China’s“dual carbon”strategic objectives,the Beijing-Tianjin-Hebei(BTH)region faces an urgent need to transition fromits traditional economic growth model,which is heavily reliant on resource consumption.This study investigates the decoupling dynamics among economic growth,energy consumption,and carbon emissions in the BTH region,along with the underlying driving forces,aiming to provide valuable insights for achieving the“dual carbon”targets and fostering high-quality regional development.First,the Tapio decoupling model is employed to analyze the decoupling relationships between economic growth,energy consumption,and carbon emissions in the BTH region from 2000 to 2021.Second,the Logarithmic Mean Divisia Index decomposition method is applied to identify the key driving factors of carbon emission reduction and quantify their respective contributions.Finally,targeted policy recommendations are proposed based on the empirical findings to support regional coordinated development.The results indicate that(1)all three sub-regions within the BTH region have demonstrated consistent improvements in energy utilization efficiency and a gradual decline in carbon emission intensity,although the degree of progress varies across regions;(2)differentiated decoupling states exist between carbon emissions and both economic growth and energy consumption,with Beijing showing significant decoupling,while Tianjin and Hebei Province experience a“rebound”phenomenon following a phase of decoupling;(3)energy consumption intensity and industrial structure optimization have notably positive effects on carbon emission reduction,whereas other factors contribute to varying degrees to the exacerbation of carbon emissions;(4)the impacts of driving factors on carbon emissions exhibit significant spatio-temporal disparities.Based on these findings,the study recommends enhancing fiscal incentives,optimizing industrial structures,improving energy efficiency,and establishing a coordinated regional governance framework to facilitate the BTH region’s low-carbon transition and sustainable development. 展开更多
关键词 Beijing-Tianjin-Hebei(BTH)region carbon emissions decoupling relationship LMDI factor decomposition
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Synergetic monitoring of pressure and temperature stimulations in multisensory electronic skin based on time decoupling effect
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作者 Zhiyi Gao Ye Zhang +10 位作者 Zhenyu Hu Dongdong Zhang Shengbin Li Huiyun Xiao Ziyin Xiang Dan Xu Haifeng Zhang Yuanzhao Wu Yiwei Liu Jie Shang Runwei Li 《Carbon Energy》 2025年第1期52-63,共12页
The progress from intelligent interactions requires electronic skin(E-skin)to shift from single-functional perception to multisensory capabilities.However,the intuitive and interference-free reading of multiple sensor... The progress from intelligent interactions requires electronic skin(E-skin)to shift from single-functional perception to multisensory capabilities.However,the intuitive and interference-free reading of multiple sensory signals without involving complex algorithms is a critical challenge.Herein,we propose a flexible multisensory E-skin by developing a highly homogeneous dispersion of BaTiO_(3)nanoparticles in polydimethylsiloxane dielectric layer.The E-skin is sensitive to externally applied pressure as well as temperature and can distinguish dual synergetic stimuli by the time decoupling effect.The pressure and temperature perception was achieved in an individual device,which greatly reduced the structural complexity compared with multifunctional integrated devices.The sensitivity of E-skin for pressure detection is as high as 0.0724 kPa^(−1)and the detection range reaches as wide as 15.625-10 MPa.The sensitivity to temperature detection is as high as−1.34℃^(−1)and the detection range reaches 20-200℃.More importantly,by equipping with a multilayer neural network,the evolution from tactile perception to advanced intelligent tactile cognition is demonstrated. 展开更多
关键词 E-skin intelligent tactile cognition machine learning multifunctional sensing time decoupling effect
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Decoupling control for tailless aircraft based fractional-order error extended state observer
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作者 Yunlong Hu Mingfei Zhao +2 位作者 Jia Song Wenling Li Yang Liu 《Control Theory and Technology》 2025年第3期397-409,共13页
The elimination of the vertical tail in tailless aircraft results in a significant decrease in heading static stability,causing substantial coupling among the three control channels.In addition,in specific operational... The elimination of the vertical tail in tailless aircraft results in a significant decrease in heading static stability,causing substantial coupling among the three control channels.In addition,in specific operational scenarios,the tailless aircraft is prone to electromagnetic interference,leading to the generation of high-frequency noise and consequently compromising their control performance.To address these issues,a decoupling control method based on a fractional-order error extended state observer(FOEESO)is proposed.A nonlinear model of a tailless aircraft with thrust vectoring capabilities is first developed.The decoupling control design for the three control channels is then implemented using FOEESO,with the asymptotic convergence conditions outlined.The proposed method is evaluated through simulations and compared to coupled control and linear extended state observer(LESO)techniques.Numerical simulations demonstrate that the FOEESO-based control methodology achieves effective decoupling,exhibiting 6.9%and 11.7%reductions in integral absolute error(IAE)relative to LESO under nominal operational conditions and critical fault scenarios,respectively.These improvements thereby highlight FOEESO’s capability to enhance closed-loop stability and tracking precision in tailless aircraft control systems. 展开更多
关键词 Tailless aircraft decoupling control ADRC High-frequency noise
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Hysteresis compensation and decoupling control of an XYΘ-type flexure-based mechanism via inverse hysteresis-coupling hybrid modeling
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作者 Yanding Qin Jie Yuan +2 位作者 Yunpeng Zhang Hui Tang Jianda Han 《Nanotechnology and Precision Engineering》 2025年第2期1-12,共12页
Planar positioning systems are widely utilized in micro and nano applications.The challenges in modeling and control of XYΘflexure-based mechanisms include hysteresis of the piezoelectric actuators,couplings among th... Planar positioning systems are widely utilized in micro and nano applications.The challenges in modeling and control of XYΘflexure-based mechanisms include hysteresis of the piezoelectric actuators,couplings among the input axes,and coupled linear and angular motions of the end effector.This paper presents an inverse hysteresis-coupling hybrid model to account for such hysteresis and couplings.First,a specially designed kinematic chain is adopted to transfer the pose of the end effector into the linear motions at three prismatic joints.Second,an inverse hysteresis-coupling hybrid model is developed to linearize and decouple the system via a multilayer feedforward neural network.A fractional-order PID controller is also integrated to improve the motion accuracy of the overall system.Experimental results demonstrate that the proposed method can accurately control the motion of the end effector with improved accuracy and robustness. 展开更多
关键词 Flexure-based mechanism Micro-vision-aided measurement Hysteresis compensation decoupling control
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Repetitive control without inductance decoupling for VSR control strategy of DC charging pile
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作者 LIU Peijin SUN Changhe +2 位作者 HE Lin ZHANG Xiangrui FENG Zhengming 《Journal of Measurement Science and Instrumentation》 2025年第1期96-106,共11页
A control strategy of repetitive control without inductorance decoupling was proposed to address the problem of high total harmonic distortion(THD)rate of the network-side current caused by the reduced stability of th... A control strategy of repetitive control without inductorance decoupling was proposed to address the problem of high total harmonic distortion(THD)rate of the network-side current caused by the reduced stability of the rectifier module of the DC charging pile under weak grid as well as the dead zone and nonlinearity of switching devices during charging.Firstly,the parallel repetitive control was constructed in the inner current loop,and the proportional-integral(PI)+repetitive controller based on parallel structure was designed.For system compensation,a second-order low-pass filter was selected to correct the system,and the network-side current harmonics were actively suppressed without increasing the filtering device,which effectively improves the quality of grid-connected current.Secondly,based on the synthetic vector method,the controller parameters were designed to realize the elimination of main pole by establishing two synchronous rotation coordinate system vector differential equations,so as to realize the inductanceless decoupling to cope with the influence of network-side inductance fluctuation on the stability of the control system under weak grid.By theoretical analysis and simulation,the proposed control strategy was embedded into the self-developed digital signal processor for the rectifier module of DC charging pile,simulated dynamic and steady-state operation experiments were conducted,and comparative analysis was performed to prove the feasibility of the proposed control strategy. 展开更多
关键词 weak grid DC charging pile voltage source rectifier(VSR) repetitive control inductanceless decoupling
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Decoupling economic growth from industrial SO_(2)emissions in China:A two-stage decomposition approach
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作者 Yuanna Tian Yizhong Wang +3 位作者 Ye Hang Dequn Zhou Xiurong Hu Qunwei Wang 《Chinese Journal of Population,Resources and Environment》 2025年第1期49-61,共13页
Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving fac... Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving factors at both the generation and treatment stages of SO_(2),more effective targeted mitigation strategies can be developed.We employ the Tapio decoupling model and propose a two-stage method to examine the decoupling issues related to SO_(2).Our findings indicate that:①DEI shows a steady and significant improvement,with SO_(2)emission intensity identified as the primary driver.②for the decoupling of economic growth and SO_(2)generation,energy scale serves as the largest stimulator,while the effect of energy intensity changes from negative to positive,and pollution intensity is first positive and then negative.③For the decoupling of SO_(2)generation and SO_(2)removal,treatment efficiency leads as the largest promoter,followed by treatment intensity.Based on these results,this study recommends that China focuses more on enhancing clean energy utilization and the effectiveness of treatment processes. 展开更多
关键词 Driving factors Tapio decoupling indicator LMDI decomposition Two-stage method
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Phase-modulated dynamical decoupling sequences robust to systematic amplitude error
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作者 Sijie Chen Guanxing Chen +3 位作者 Jiahao Huang Peiliang Liu Min Zhuang Chaohong Lee 《Chinese Physics B》 2025年第7期315-324,共10页
Dynamical decoupling(DD),usually implemented by sophisticated sequences of instantaneous control pulses,is a well-established quantum control technique for quantum information and quantum sensing.In practice,the pulse... Dynamical decoupling(DD),usually implemented by sophisticated sequences of instantaneous control pulses,is a well-established quantum control technique for quantum information and quantum sensing.In practice,the pulses are inevitably imperfect with many systematic errors that may influence the performances of DD.In particular,Rabi error and detuning are primary systemic errors arising from finite pulse duration,incorrect time control,and frequency instability.Here,we propose a phase-modulated DD with staggered global phases for the basic units of the pulse sequences to suppress these systemic errors.By varying the global phases appended to the pulses in the dynamical decoupling unit alternatively with 0 orπ,our protocol can significantly reduce the influences of Rabi error and detuning.Our protocol is general and can be combined with the most existing DD sequences such as universal DD,knill DD,XY,etc.As an example,we further apply our method to quantum lock-in detection for measuring time-dependent alternating signals.Our study paves the way for a simple and feasible way to realize robust dynamical decoupling sequences,which can be applicable for various quantum sensing scenarios. 展开更多
关键词 dynamical decoupling quantum sensing quantum lock-in amplifier
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黄河流域农业碳排放脱钩效应及影响因素研究 被引量:1
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作者 初丽霞 王文燕 《生态经济》 北大核心 2026年第1期67-75,共9页
采用碳排放系数法测算2000—2022年黄河流域农业碳排放,并运用Tapio脱钩模型和LMDI模型分别分析其与农业经济发展水平的关系和影响因素。结果表明:2000—2022年黄河流域农业碳排放整体呈现先上升后下降的趋势,碳排放强度呈波动下降趋势... 采用碳排放系数法测算2000—2022年黄河流域农业碳排放,并运用Tapio脱钩模型和LMDI模型分别分析其与农业经济发展水平的关系和影响因素。结果表明:2000—2022年黄河流域农业碳排放整体呈现先上升后下降的趋势,碳排放强度呈波动下降趋势,并且畜禽养殖是农业碳排放的主要来源,山东、河南是农业碳排放的主要贡献省份。在脱钩关系上,黄河流域整体农业碳排放与农业经济增长间呈现强弱脱钩交替的有利状态,各省份脱钩状态存在差异。影响因素方面,在时序分解和区域比较上均表现为农业经济发展水平为农业碳排放的增排因素,而农业生产效率是第一抑制因素。可以通过推广低碳农业发展方式、实施分区精准治理及加强碳排放驱动因素管理等措施来减少黄河流域农业碳排放。 展开更多
关键词 农业碳排放 Tapio脱钩 LMDI模型 黄河流域
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基于无人机的竹产品与疫木下山吊运系统设计与试验
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作者 陈洪立 王冠凯 +5 位作者 张文福 张建 黄宏亮 杨振华 赵胤 杜小强 《林业科学》 北大核心 2026年第1期177-187,共11页
【目的】针对当前竹产品伐后下山主要依靠人工搬运、拖车运输存在劳动强度大、运送效率低、人力成本高及安全事故频发等问题,设计一种基于无人机的竹产品与疫木下山吊运系统,实现无人机在竹林或树林间的自主吊运并在危险情况下紧急脱困... 【目的】针对当前竹产品伐后下山主要依靠人工搬运、拖车运输存在劳动强度大、运送效率低、人力成本高及安全事故频发等问题,设计一种基于无人机的竹产品与疫木下山吊运系统,实现无人机在竹林或树林间的自主吊运并在危险情况下紧急脱困保护无人机安全的功能,减少人工参与、保障作业安全并克服山地垂直落差大的问题,推动毛竹产业向智能化、高效化发展。【方法】利用测定的竹梢和竹段形态特征参数,设计吊挂自动脱钩装置和无人机紧急脱困装置,应用SOLIDWORKS软件建立装置的三维模型,并开发驱动设备的软硬件系统。基于ANSYS Workbench软件的静态结构分析、静磁分析对吊运装置的关键结构进行仿真和理论计算,确定结构参数和电磁铁型号。进行室内试验,分析打包方式(魔术贴、凹扣和绳结)的效率、脱钩方式(重力钩和电磁主动钩)的稳定性和脱困机构的可行性。开展林间试验,测试整套吊运系统在实际工作场景下的效率和稳定性。【结果】室内试验表明,魔术贴打包方式平均用时21 s、凹扣组平均用时22.2 s、绳结组平均用时25.8 s,选用魔术贴进行打包;重力钩脱钩成功率为80%、电磁主动钩脱钩成功率为90%,确认采用电磁主动钩脱钩方式。林间试验结果显示,脱钩成功率为90%,其中挂钩平均耗时14.69 s,脱钩平均耗时1.19 s。在上升、下降和前进状态下,脱困成功率分别为80%、90%和90%。【结论】基于无人机的竹产品与疫木下山吊运系统能够减少人工参与、提高运送效率、降低成本和发生安全事故的概率,可满足现场应用需求。 展开更多
关键词 无人机 竹林吊运 紧急脱困 自动脱钩 仿真优化 林业应用
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煤炭超临界水气化-氧化解耦式制氢系统能效分析
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作者 王浩 孙维东 +1 位作者 王闯 吕友军 《西安交通大学学报》 北大核心 2026年第2期59-70,共12页
针对煤炭超临界水气化制氢系统整体能量集成优化不足的问题,提出了一种以1000 m^(3)·h^(-1)氢气产量(在0℃、1个大气压的标准条件下)为目标的煤炭超临界水气化-氧化解耦式超临界水制氢示范系统,并基于热力学方法对该系统进行了能... 针对煤炭超临界水气化制氢系统整体能量集成优化不足的问题,提出了一种以1000 m^(3)·h^(-1)氢气产量(在0℃、1个大气压的标准条件下)为目标的煤炭超临界水气化-氧化解耦式超临界水制氢示范系统,并基于热力学方法对该系统进行了能效分析。基于不同煤种的气化特性确定了解耦式系统的设计参数,考察了不同煤质、温度和压力对系统能量效率的影响规律;根据图像㶲分析方法揭示了气化器、氧化器、换热器组和系统整体不可逆损失的产生机理。结果表明:在水煤质量比为1∶4,质量流量为1280 kg·h^(-1)的条件下,红柳林煤的制氢效率高达66.92%;系统制氢效率随着预热水温度的增加呈现出先增加后下降的趋势,随着反应压力的增加,总产气量和氢气产量均下降;系统中气化反应器和氧化反应器的不可逆损失最大,高品位产气与低品位吸热混合工质之间存在较大品位差距是不可逆损失产生的主要原因;减少换热器不可逆损失的途径是减少冷热流体的品位差,即减少换热全过程的温度差。该研究结果可为煤炭超临界水气化制氢系统设计提供技术参考。 展开更多
关键词 超临界水气化 解耦式系统 图像㶲分析 热力学
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民营企业社会责任脱耦会影响可持续发展能力吗?——基于同群效应视角
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作者 鲁锦涛 苗青 +2 位作者 贾小榕 宋马林 林文芳 《管理评论》 北大核心 2026年第2期43-55,共13页
近年来,企业社会责任承诺与执行效果的偏离现象时有发生,给企业可持续发展能力的提升带来严峻挑战。现有研究大多将企业社会责任脱耦视为应对制度压力的策略工具,鲜有对企业因同行业同地区模仿引发的责任脱耦同群效应及其对可持续发展... 近年来,企业社会责任承诺与执行效果的偏离现象时有发生,给企业可持续发展能力的提升带来严峻挑战。现有研究大多将企业社会责任脱耦视为应对制度压力的策略工具,鲜有对企业因同行业同地区模仿引发的责任脱耦同群效应及其对可持续发展能力的作用机制进行系统性探究。本文运用2014—2020年中国A股上市民营企业数据,通过构建多元回归模型,实证检验了民营企业社会责任脱耦同群效应的存在性。基于社会传染理论,本文从抑制性传染、回声性传染和歇斯底里性传染三个视角探析了同群效应的产生机制,社会网络嵌入度对民营企业社会责任脱耦同群效应的调节作用,以及税收优惠对民营企业社会责任脱耦同群效应与企业可持续发展能力之间关系的调节效应。研究发现,民营企业社会责任脱耦存在同群效应,并表现为地区同群效应和行业同群效应;社会网络嵌入度抑制了民营企业社会责任脱耦的同群效应;民营企业社会责任脱耦同群效应对企业可持续发展能力的影响呈现先促进后抑制的倒“U”型。此外,税收优惠缓解了民营企业社会责任脱耦同群效应与企业可持续发展能力之间的倒“U”型关系。研究结论为民营企业高质量履行社会责任与提升可持续发展能力提供了理论借鉴与实践指导。 展开更多
关键词 企业社会责任脱耦 同群效应 社会传染 可持续发展 税收优惠
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轴向水不耦合装药结构爆破空气流场应力演化分析
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作者 王雁冰 孔维文 +2 位作者 汪东宸 杨柳 郝宪杰 《工程科学与技术》 北大核心 2026年第2期239-252,共14页
为研究不同轴向水不耦合形式对爆破效果的影响,通过高速纹影系统和超压测试系统并结合有限元ANSYS AUTODYN数值模拟,对轴向水不耦合结构在空气流场中起爆后冲击波的传播规律开展研究。以结构中装药段的位置为变量,设计4种水不耦合形式... 为研究不同轴向水不耦合形式对爆破效果的影响,通过高速纹影系统和超压测试系统并结合有限元ANSYS AUTODYN数值模拟,对轴向水不耦合结构在空气流场中起爆后冲击波的传播规律开展研究。以结构中装药段的位置为变量,设计4种水不耦合形式下的药包,通过纹影照片分析爆炸冲击波和爆生产物的波动变化,对比分析4种结构下冲击波的传播过程、速度变化、压力变化,并将数值模拟结果与纹影试验结果结合,得到炸药冲击波在空气流场中传播速度、压力的演化过程以及在药包内部的压力分布规律。结果显示:轴向水不耦合结构爆炸产生的能量在垂直于炮孔轴线方向比沿炮孔轴线方向更为集中。炸药起爆后产生的冲击波以扁球形在空气流场中传播,爆生产物随冲击波向外传播并逐渐与其分离,且在垂直方向上的位移更远;轴向水不耦合装药结构的爆炸冲击波压力受传播路径上介质的影响,含水耦合一侧的冲击波超压峰值低,但在相同传播距离上衰减速度更慢,冲击波作用时间更长,使该侧爆破作用影响范围更大。轴向水不耦合结构中装药段位置会对爆破效果产生影响,装药段的孔壁压力远大于水介质段,远离装药段的孔壁超压峰值低,因此,破坏范围主要在装药段产生,可以通过改变装药结构中炸药的段数、长度和位置来控制损伤的范围。 展开更多
关键词 高速纹影 轴向装药 水不耦合 孔壁压力 ANSYS AUTODYN
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路径解耦的搬运机器人运行轨迹优化控制
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作者 武彩霞 郁汉琪 蒋勇英 《机械设计与制造》 北大核心 2026年第3期325-331,共7页
为提高搬运机器人在充满静态障碍的环境中物品搬运的效率,提出了一种路径解耦的搬运机器人运行轨迹优化控制算法。该算法首先通过路径曲率定义运动剖面的最大加速度和速度限制。然后估计路径在所有路径点的切线、曲率和曲率导数,并利用... 为提高搬运机器人在充满静态障碍的环境中物品搬运的效率,提出了一种路径解耦的搬运机器人运行轨迹优化控制算法。该算法首先通过路径曲率定义运动剖面的最大加速度和速度限制。然后估计路径在所有路径点的切线、曲率和曲率导数,并利用插值算法得到已知路径曲率和具有三阶几何连续性的光滑完整路径曲线。最后通过设计满足系统安全约束和充分考虑搬运路径曲线局部特征的物品搬运速度剖面,确保搬运机器人安全、快速地将物品移动到目标位置。通过解决搬运机器人在充满静态障碍的杂乱环境中的物品搬运问题,验证了所提算法的有效性。验证结果表明,相比于休息到休息的传统控制算法,路径解耦的搬运机器人运行轨迹优化控制算法,在总路径长度相同的情况下,物品搬运总用时减少了23.71%。因此,路径解耦的搬运机器人运行轨迹优化控制算法将具有良好的实际应用价值。 展开更多
关键词 搬运机器人 运动轨迹优化控制 路径解耦 路径曲率
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跨层级交互与方位感知的航拍图像语义分割
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作者 刘杰 吴紫钰 +1 位作者 田明 韩轲 《光学精密工程》 北大核心 2026年第2期267-278,共12页
针对航拍图像语义分割中提取特征尺度单一、细节丢失、边界模糊的问题,本文提出一种跨层级交互与方位感知的航拍图像语义分割网络。通过方向解耦注意力策略构建方位感知模块,增强模型对空间方向信息的处理能力;设计跨层级交互模块进行... 针对航拍图像语义分割中提取特征尺度单一、细节丢失、边界模糊的问题,本文提出一种跨层级交互与方位感知的航拍图像语义分割网络。通过方向解耦注意力策略构建方位感知模块,增强模型对空间方向信息的处理能力;设计跨层级交互模块进行跨通道特征交互融合,提升空间感知能力,同时利用通道-空间注意力机制增强特征提取能力,在复杂场景中缓解细节模糊问题;最后对分割头进行轻量化设计,去除冗余操作,在降低计算量的同时保证分割性能。实验结果表明,本文网络在UAVid数据集与Aeroscapes数据集的平均交并比相较于基线模型SegFormer分别提升了1.7%和1.3%,证明了该网络在航拍图像等复杂情况下语义分割的有效性。Human类别相较基线模型分割精度提升了1.8%,证明了本文网络在小目标分割方面表现出色。与多个主流网络相比,本文方法在两个数据集上均实现了最高的分割精度,表现出更优的泛化能力。 展开更多
关键词 跨层级交互 语义分割 航拍图像 轻量化 方向解耦
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危机转化视角下中国省际碳排放与经济发展的脱钩“链式”反应分析
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作者 杨青 段召琳 +3 位作者 刘星星 陈英杰 吴婵媛 汪金美 《环境科学》 北大核心 2026年第2期727-740,共14页
碳排放与经济发展脱钩是实现“双碳”目标的重要抓手,但脱钩状态的不稳定迫使地区低碳发展极易陷入“增碳减效”(强负脱钩)和“强增碳弱增效”(增长负脱钩)的双重“危机”.因此,基于Tapio模型分析2010~2021年中国30个省(区、市)碳排放... 碳排放与经济发展脱钩是实现“双碳”目标的重要抓手,但脱钩状态的不稳定迫使地区低碳发展极易陷入“增碳减效”(强负脱钩)和“强增碳弱增效”(增长负脱钩)的双重“危机”.因此,基于Tapio模型分析2010~2021年中国30个省(区、市)碳排放脱钩状态的时空演变特征,构建碳排放脱钩危机转化评价模型,探讨碳脱钩状态是否向好转变的链式反应特征.结果发现:①中国碳脱钩进程虽整体向好,但暴露出高碳依赖模式的系统性风险,部分地区通过危机倒逼机制成功突破路径锁定,形成“低碳突围”示范效应,验证了危机驱动的转型可行性;②碳排放脱钩的危机转化效能存在“半程困境”(转化率为40%~50%),既反映传统发展惯性的持续阻力,也揭示区域分化背后的政策响应差异;③脱钩状态的“链式跃迁”特征表明,危机转化具有“风险解构-要素重置-发展转型”的动态累积效应;④能源强度的核心驱动作用与单位能耗碳排放的积极作用,凸显驱动危机转化的双重路径,短期依赖强度调控可能加剧波动风险,而效率提升才是化解“减排-增长”矛盾的系统性解方. 展开更多
关键词 碳排放 脱钩 危机转化 马尔可夫链 减碳增效
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