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
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
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
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
One kind of movable-pair analysis method is adopted to analyze the configuration of a 3-7R (revolute-pair) parallel decoupling mechanism, and the mechanism's characteristics are summarized. The mechanism has three ...One kind of movable-pair analysis method is adopted to analyze the configuration of a 3-7R (revolute-pair) parallel decoupling mechanism, and the mechanism's characteristics are summarized. The mechanism has three orthogonal distributional branch-chains, and all movable pairs are rotational joints. The movable platform of the mechanism has x, y, z translational decoupling directions. Furthermore, in order to verify the mechanism's decoupling characteristics, the mechanism's kinematics analysis is solved, and the mechanism's direct/inverse kinematics model, input/output velocities and accelerations are deduced, which confirm its decoupling movement characteristics. Finally, one kind of mechanism link decomposed-integrated approach is adopted, and the mechanism's dynamics model is completed with the Lagrange method, which also proves its decoupling force characteristics. All of these works provide significant theory for the further study of the mechanism's control strategy, design, path planning etc.展开更多
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
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
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
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
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
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
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
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
The notions of decoupling zeros of positive discrete-time linear systems are introduced. The relationships between the decoupling zeros of standard and positive discrete-time linear systems are analyzed. It is shown t...The notions of decoupling zeros of positive discrete-time linear systems are introduced. The relationships between the decoupling zeros of standard and positive discrete-time linear systems are analyzed. It is shown that: 1) if the positive system has decoupling zeros then the corresponding standard system has also decoupling zeros, 2) the positive system may not have decoupling zeros when the corresponding standard system has decoupling zeros, 3) the positive and standard systems have the same decoupling zeros if the rank of reachability (observability) matrix is equal to the number of linearly independent monomial columns (rows) and some additional assumptions are satisfied.展开更多
Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling ...Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod.展开更多
Use stable inversion to accomplish precise decoupling tracking of airspeed and altitude for conventional takeoff and landing of unmanned aerial vehicles (UAVs) is in essence a non-minimum phase output tracking problem...Use stable inversion to accomplish precise decoupling tracking of airspeed and altitude for conventional takeoff and landing of unmanned aerial vehicles (UAVs) is in essence a non-minimum phase output tracking problem. The main contribution of this article is that a new method to calculate the causal solution of stable inversion is proposed by introducing a well defined perturbed signal to the system’s unstable internal dynamics. It is helpful to overcome the pitfalls resulting from non-causality in existin...展开更多
Load distribution is the foundation of shape control and gauge control, in which it is necessary to take into account the shape control ability of TCM (tandem cold mill) for strip shape and gauge quality. First, the...Load distribution is the foundation of shape control and gauge control, in which it is necessary to take into account the shape control ability of TCM (tandem cold mill) for strip shape and gauge quality. First, the objective function of generalized shape and gauge decoupling load distribution optimization was established, which considered the rolling force characteristics of the first and last stands in TCM, the relative power, and the TCM shape control ability. Then, IGA (immune genetic algorithm) was used to accomplish this multi-objective load distribution optimization for TCM. After simulation and comparison with the practical load distribution strategy in one tandem cold mill, general- ized shape and gauge decoupling load distribution optimization on the basis of IGA approved good ability of optimizing shape control and gauge control simultaneously.展开更多
In order to make the static state feedback nonlinear decoupling control law for a kind of missile to be easy for implementation in practice, an improvement is discussed. The improvement method is to introduce a BP neu...In order to make the static state feedback nonlinear decoupling control law for a kind of missile to be easy for implementation in practice, an improvement is discussed. The improvement method is to introduce a BP neural network to approximate the decoupling control laws which are designed for different aerodynamic characteristic points, so a new decoupling control law based on BP neural network is produced after the network training. The simulation results on an example illustrate the approach obtained feasible and effective.展开更多
This paper presents a comparative study of different decoupling control schemes for a two-input, two-output(TITO) binary distillation column via proportional-integral(PI)controller. The key idea behind this paper is d...This paper presents a comparative study of different decoupling control schemes for a two-input, two-output(TITO) binary distillation column via proportional-integral(PI)controller. The key idea behind this paper is designing two novel fuzzy decoupling schemes that depend on human knowledge,instead of the system mathematical model used in conventional decoupling schemes. Based on conventional and inverted decoupling schemes, fuzzy and inverted fuzzy decoupling schemes are developed. The control effect is compared using simulation results for the proposed two schemes with conventional decoupling and inverted decoupling. The proposed fuzzy decoupling schemes are easy to realize and simple to design, besides they have a good decoupling capability. Two methods are used to prove asymptotic stability of each loop and the entire closed-loop system by applying the proposed fuzzy decoupling-based PI controller.The Wood and Berry model of a binary distillation column is used to illustrate the applicability of the proposed schemes.展开更多
Water decoupling charge blasting excels in rock breaking,relying on its uniform pressure transmission and low energy dissipation.The water decoupling coefficients can adjust the contributions of the stress wave and qu...Water decoupling charge blasting excels in rock breaking,relying on its uniform pressure transmission and low energy dissipation.The water decoupling coefficients can adjust the contributions of the stress wave and quasi-static pressure.However,the quantitative relationship between the two contributions is unclear,and it is difficult to provide reasonable theoretical support for the design of water decoupling blasting.In this study,a theoretical model of blasting fracturing partitioning is established.The mechanical mechanism and determination method of the optimal decoupling coefficient are obtained.The reliability is verified through model experiments and a field test.The results show that with the increasing of decoupling coefficient,the rock breaking ability of blasting dynamic action decreases,while quasi-static action increases and then decreases.The ability of quasi-static action to wedge into cracks changes due to the spatial adjustment of the blast hole and crushed zone.The quasi-static action plays a leading role in the fracturing range,determining an optimal decoupling coefficient.The optimal water decoupling coefficient is not a fixed value,which can be obtained by the proposed theoretical model.Compared with the theoretical results,the maximum error in the model experiment results is 8.03%,and the error in the field test result is 3.04%.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.12172149,12172151,and 12202378)the MOE Key Laboratory of Fututer Intelligent Manufacturing Technologies for High-End Equipment of China(No.FIMFYUST-2025B07)+1 种基金the Guangzhou Municipal Bureau of Science and Technology of China(No.SL2023A04J01461)the Ministry of Science and Technology of China(No.G20221990122)。
文摘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.
基金supported by the National Science Foundationof China(Nos.52305127 and 52475130)。
文摘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.
基金support by Hong Kong RGC General Research Fund(16217824,16213825,16203923,and 16217824)National Natural Science Foundation of China(N_HKUST638/23)+1 种基金Research Grants Council Joint Research Scheme(62361166630)Guangdong Basic and Applied Basic Research Foundation(2023B1515130007).
文摘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.
基金supported by the Shanghai Committee of Science and Technology Fund(22ZR1419300)the Academic Year 2025 Ritsumeikan Asia Pacific University Academic Research Subsidy(Grants-in-Aid Reapplication Type).
文摘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.
基金The National High Technology Research and Development Program of China(863Program)(No.2006AA040202)
文摘One kind of movable-pair analysis method is adopted to analyze the configuration of a 3-7R (revolute-pair) parallel decoupling mechanism, and the mechanism's characteristics are summarized. The mechanism has three orthogonal distributional branch-chains, and all movable pairs are rotational joints. The movable platform of the mechanism has x, y, z translational decoupling directions. Furthermore, in order to verify the mechanism's decoupling characteristics, the mechanism's kinematics analysis is solved, and the mechanism's direct/inverse kinematics model, input/output velocities and accelerations are deduced, which confirm its decoupling movement characteristics. Finally, one kind of mechanism link decomposed-integrated approach is adopted, and the mechanism's dynamics model is completed with the Lagrange method, which also proves its decoupling force characteristics. All of these works provide significant theory for the further study of the mechanism's control strategy, design, path planning etc.
基金supported by the Strategic Priority Research Programs of Chinese Academy of Sciences (XDA29020401)the Fund of State Key Laboratory of Mesoscience and Engineering (Meso-23-A02)。
文摘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.
基金Ningbo Scientific and Technological Innovation 2025 Major Project,Grant/Award Number:2020Z022German Research Foundation(DFG)grants,Grant/Award Numbers:MA 5144/13-1,MA 5144/28-1+6 种基金the National Natural Science Foundation of China,Grant/Award Numbers:62204246,51931011,51971233,52127803,62174165the External Cooperation Program of Chinese Academy of Sciences,Grant/Award Numbers:174433KYSB20190038,174433KYSB20200013the Instrument Developing Project of the Chinese Academy of Sciences,Grant/Award Number:YJKYYQ20200030K.C.Wong Education Foundation,Grant/Award Number:GJTD-2020-11Chinese Academy of Sciences Youth Innovation Promotion Association,Grant/Award Number:2018334Zhejiang Provincial Key R&D Program,Grant/Award Numbers:2021C01183,2022C01032the National Natural Science Foundation of Zhejiang Province of China,Grant/Award Number:LQ23F040004.
文摘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.
基金funded by the Science and Technology Project of State Grid Corporation of China(No.52018F240002)the National Natural Science Foundation of China(72403087)the National Natural Science Foundation of China(72173043).
文摘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.
文摘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.
基金supported in part by the Open Fund of State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment,Guangdong University of Technology(Grant No.JMDZ2021007)in part by the Guangdong International Cooperation Program of Science and Technology(Grant No.2022A0505050078).
文摘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.
基金the National Natural Science Foundation of China[Grant No.52270183].
文摘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.
基金supported by National Natural Science Foundation of China(No.61903291)Shaanxi Province Key R&D Program(No.2022GY-134)。
文摘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.
基金Project supported by the National Key Research and Development Program of China(Grant No.2022YFA1404104)the National Natural Science Foundation of China(Grant Nos.92476201,12025509,12305022,and 12475029)+1 种基金the Key-Area Research and Development Program of Guangdong Province,China(Grant No.2019B030330001)Guangdong Provincial Quantum Science Strategic Initiative Fund(Grant Nos.GDZX2305006 and GDZX2405002)。
文摘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.
文摘The notions of decoupling zeros of positive discrete-time linear systems are introduced. The relationships between the decoupling zeros of standard and positive discrete-time linear systems are analyzed. It is shown that: 1) if the positive system has decoupling zeros then the corresponding standard system has also decoupling zeros, 2) the positive system may not have decoupling zeros when the corresponding standard system has decoupling zeros, 3) the positive and standard systems have the same decoupling zeros if the rank of reachability (observability) matrix is equal to the number of linearly independent monomial columns (rows) and some additional assumptions are satisfied.
基金Supported by Scientific Research Foundation of Yunnan Provincial Department of Education(2015J088)~~
文摘Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod.
基金Weapons Equipment Pre-research Foundation of China (9140 A25040106HK0118)
文摘Use stable inversion to accomplish precise decoupling tracking of airspeed and altitude for conventional takeoff and landing of unmanned aerial vehicles (UAVs) is in essence a non-minimum phase output tracking problem. The main contribution of this article is that a new method to calculate the causal solution of stable inversion is proposed by introducing a well defined perturbed signal to the system’s unstable internal dynamics. It is helpful to overcome the pitfalls resulting from non-causality in existin...
基金Item Sponsored by National Significant Technology and Equipment Research Project of China (ZZ02-13B-03)
文摘Load distribution is the foundation of shape control and gauge control, in which it is necessary to take into account the shape control ability of TCM (tandem cold mill) for strip shape and gauge quality. First, the objective function of generalized shape and gauge decoupling load distribution optimization was established, which considered the rolling force characteristics of the first and last stands in TCM, the relative power, and the TCM shape control ability. Then, IGA (immune genetic algorithm) was used to accomplish this multi-objective load distribution optimization for TCM. After simulation and comparison with the practical load distribution strategy in one tandem cold mill, general- ized shape and gauge decoupling load distribution optimization on the basis of IGA approved good ability of optimizing shape control and gauge control simultaneously.
文摘In order to make the static state feedback nonlinear decoupling control law for a kind of missile to be easy for implementation in practice, an improvement is discussed. The improvement method is to introduce a BP neural network to approximate the decoupling control laws which are designed for different aerodynamic characteristic points, so a new decoupling control law based on BP neural network is produced after the network training. The simulation results on an example illustrate the approach obtained feasible and effective.
文摘This paper presents a comparative study of different decoupling control schemes for a two-input, two-output(TITO) binary distillation column via proportional-integral(PI)controller. The key idea behind this paper is designing two novel fuzzy decoupling schemes that depend on human knowledge,instead of the system mathematical model used in conventional decoupling schemes. Based on conventional and inverted decoupling schemes, fuzzy and inverted fuzzy decoupling schemes are developed. The control effect is compared using simulation results for the proposed two schemes with conventional decoupling and inverted decoupling. The proposed fuzzy decoupling schemes are easy to realize and simple to design, besides they have a good decoupling capability. Two methods are used to prove asymptotic stability of each loop and the entire closed-loop system by applying the proposed fuzzy decoupling-based PI controller.The Wood and Berry model of a binary distillation column is used to illustrate the applicability of the proposed schemes.
基金funded by the National Natural Science Foundation of China(No.42372331)the Henan Excellent Youth Science Fund Project(No.242300421145)the Colleges and Universities Youth and Innovation Science and Technology Support Plan of Shandong Province(No.2021KJ024).
文摘Water decoupling charge blasting excels in rock breaking,relying on its uniform pressure transmission and low energy dissipation.The water decoupling coefficients can adjust the contributions of the stress wave and quasi-static pressure.However,the quantitative relationship between the two contributions is unclear,and it is difficult to provide reasonable theoretical support for the design of water decoupling blasting.In this study,a theoretical model of blasting fracturing partitioning is established.The mechanical mechanism and determination method of the optimal decoupling coefficient are obtained.The reliability is verified through model experiments and a field test.The results show that with the increasing of decoupling coefficient,the rock breaking ability of blasting dynamic action decreases,while quasi-static action increases and then decreases.The ability of quasi-static action to wedge into cracks changes due to the spatial adjustment of the blast hole and crushed zone.The quasi-static action plays a leading role in the fracturing range,determining an optimal decoupling coefficient.The optimal water decoupling coefficient is not a fixed value,which can be obtained by the proposed theoretical model.Compared with the theoretical results,the maximum error in the model experiment results is 8.03%,and the error in the field test result is 3.04%.