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Dynamic Stability Analysis of Wedge in Rock Slope Based on Kinetic Vector Method 认领 引用 被引量：6
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作者 Weida Ni Huiming Tang +2 位作者 Xiao Liu Rui Yong Zongxing Zou 《Journal of Earth Science》 SCIE CAS CSCD 2014年第4期749-756,共8页
A new method （kinetic vector method, KVM） is presented for analyzing the dynamic stability of wedge in rock slope. The dynamic analysis is carried out based on three dimensional distinct element code （3DEC）, and t... A new method （kinetic vector method, KVM） is presented for analyzing the dynamic stability of wedge in rock slope. The dynamic analysis is carried out based on three dimensional distinct element code （3DEC）, and the kinetic inertial force of the wedge under seismic loading can be obtained via calculating the net vectorial nodal force of the finite difference grid. Then, the factor of safety （FOS） of the wedge can be calculated based on limit equilibrium method （LEM） at each dynamic analysis step, therefore time series of the FOS for whole earthquake process can be obtained. For the purpose of evaluating the entire dynamic stability of the wedge, dynamic factor of safety （DFOS） is proposed and defined as a numerical value corresponding with a given rate of probability guarantee based on reliability theory. Consequently, the KVM inherits the merits of the LEM and also has fully nonlinear dynamic analysis capabilities, and the feasibility and correctness of the KVM are tested by an example given by Hoek and Bray （1981）. Finally, a rock slope case in Wenchuan Earthquake regions of China is presented to verify the engineering practicability of the KVM, and the results matched the actual situation well. 展开更多
关键词 dynamic stability limit equilibrium discrete element kinetic vector method rock slope Wenchuan Earthquake.
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THE SOLUTION FOR TRANSIENT TWO-PHASE FLOW BY SPLIT FLUX VECTOR METHOD 认领 引用
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作者 翁荣周 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第11期1039-1046,共8页
In this paper the transient two-phase flow equations and their eigenvalues are first introduced. The flux vector is then split into subvectors which just contain a specially signed eigenvalue. Using one-sided spatial ... In this paper the transient two-phase flow equations and their eigenvalues are first introduced. The flux vector is then split into subvectors which just contain a specially signed eigenvalue. Using one-sided spatial difference operators finite difference equations and their solutions are obtained. Finally comparison with experiment shows the predicted results produce good agreement with experimental data. 展开更多
关键词 two-phase flow vector flux split flux vector method
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PREDICTION OF MAGNETOCRYSTALLINE ANISOTROPY OF POLYCRYSTALLINE MATERIALS WITH GENERALIZED VECTOR METHOD 认领 引用 被引量：1
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《Acta Metallurgica Sinica(English Letters)》 CAS 1991年第7期66-69,共4页
The crystallite orientation distribution functions(ODFs)were determined for the surface, 1/4 depth and 1/2 depth layers of a cold-rolled W20 non-oriented silicon steel sheet.By extending the theory of magnetic anisotr... The crystallite orientation distribution functions(ODFs)were determined for the surface, 1/4 depth and 1/2 depth layers of a cold-rolled W20 non-oriented silicon steel sheet.By extending the theory of magnetic anisotropy to textured materials with no sample symmetry, the variation of magnetic torque versus directions in the plane of the sheet was further calcu- lated quantitatively,which fits well with the measured torque curve. 展开更多
关键词 generalized vector method magnetic torque texture
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A combination of damage locating vector method (DLV) and differential evolution algorithm (DE) for structural damage assessment 认领 引用 被引量：3
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作者 T. NGUYEN-THOI A. TRAN-VIET +2 位作者 N. NGUYEN-MINH T. VO-DUY V. HO-HUU 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2018年第1期92-108,共17页
In this study, a two-stage method is presented for identifying multiple damage scenarios. In the first stage, the damage locating vector （DLV） method using normalized cumulative energy （nce） is employed for damage... In this study, a two-stage method is presented for identifying multiple damage scenarios. In the first stage, the damage locating vector （DLV） method using normalized cumulative energy （nce） is employed for damage localization in structures. In the second stage, the differential evolution algorithm （DE） is used for damage severity of the structures. In addition, in the second stage, a modification of an available objective function is made for handing the issue of symmetric structures. To verify the effectiveness of the present technique, numerical examples of a 72-bar space truss and a one-span steel portal frame are considered. In addition, the effect of noise on the performance of the identification results is also investigated. The numerical results show that the proposed combination gives good assessment of damage location and extent for multiple structural damage cases. 展开更多
关键词 damage assessment damage locating vector method （DLV） differential evolution （DE） multiple damagelocation assurance criterion （MDLAC） mode shape error function
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Average vector field methods for the coupled Schrdinger KdV equations 认领 引用 被引量：8
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作者 张弘 宋松和 +1 位作者 陈绪栋 周炜恩 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期242-250,共9页
The energy preserving average vector field （AVF） method is applied to the coupled Schr6dinger-KdV equations. Two energy preserving schemes are constructed by using Fourier pseudospectral method in space direction di... The energy preserving average vector field （AVF） method is applied to the coupled Schr6dinger-KdV equations. Two energy preserving schemes are constructed by using Fourier pseudospectral method in space direction discretization. In order to accelerate our simulation, the split-step technique is used. The numerical experiments show that the non-splitting scheme and splitting scheme are both effective, and have excellent long time numerical behavior. The comparisons show that the splitting scheme is faster than the non-splitting scheme, but it is not as good as the non-splitting scheme in preserving the invariants. 展开更多
关键词 coupled Schrodinger-KdV equations average vector field method splitting method Fourier pseu-dospectral method
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WAVE SUPERPOSITION METHOD BASED ON VIRTUAL SOURCE BOUNDARY WITH COMPLEX RADIUS VECTOR FOR SOLVING ACOUSTIC RADIATION PROBLEMS 认领 引用 被引量：3
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作者 XiangYu HuangYuying MaXiaoqiang 《Acta Mechanica Solida Sinica》 SCIE 2004年第1期12-19,共8页
By virtue of the comparability between the wave superposition method and the dynamic analysis of structures, a general format for overcoming the non-uniqueness of solution induced by the wave superposition method at t... By virtue of the comparability between the wave superposition method and the dynamic analysis of structures, a general format for overcoming the non-uniqueness of solution induced by the wave superposition method at the eigenfrequencies of the corresponding interior problems is proposed. By adding appropriate damp to the virtual source system of the wave superposition method, the unique solutions for all wave numbers can be ensured. Based on this thought, a novel method-wave superposition method with complex radius vector is constructed. Not only is the computational time of this method approximately equal to that of the standard wave superposition method, but also the accuracy is much higher compared with other correlative methods. Finally, by taking the pulsating sphere and oscillating sphere as examples, the results of calculation show that the present method can effectively overcome the non-uniqueness problem. 展开更多
关键词 virtual boundary integral equation wave superposition method wave superposition method with complex radius vector acoustic radiation virtual damp
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Vibration reliability analysis for aeroengine compressor blade based on support vector machine response surface method 认领 引用
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作者 高海峰 白广忱 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1685-1694,共10页
To ameliorate reliability analysis efficiency for aeroengine components, such as compressor blade, support vector machine response surface method(SRSM) is proposed. SRSM integrates the advantages of support vector mac... To ameliorate reliability analysis efficiency for aeroengine components, such as compressor blade, support vector machine response surface method(SRSM) is proposed. SRSM integrates the advantages of support vector machine(SVM) and traditional response surface method(RSM), and utilizes experimental samples to construct a suitable response surface function(RSF) to replace the complicated and abstract finite element model. Moreover, the randomness of material parameters, structural dimension and operating condition are considered during extracting data so that the response surface function is more agreeable to the practical model. The results indicate that based on the same experimental data, SRSM has come closer than RSM reliability to approximating Monte Carlo method(MCM); while SRSM(17.296 s) needs far less running time than MCM(10958 s) and RSM(9840 s). Therefore,under the same simulation conditions, SRSM has the largest analysis efficiency, and can be considered a feasible and valid method to analyze structural reliability. 展开更多
关键词 vibration reliability analysis compressor blade support vector machine response surface method natural frequency
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A vector sum analysis method for stability evolution of expansive soil slope considering shear zone damage softening 认领 引用 被引量：2
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作者 Junbiao Yan Lingwei Kong +1 位作者 Cheng Chen Mingwei Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3746-3759,共14页
Slope stability analysis is a classical mechanical problem in geotechnical engineering and engineering geology.It is of great significance to study the stability evolution of expansive soil slopes for engineering cons... Slope stability analysis is a classical mechanical problem in geotechnical engineering and engineering geology.It is of great significance to study the stability evolution of expansive soil slopes for engineering construction in expansive soil areas.Most of the existing studies evaluate the slope stability by analyzing the limit equilibrium state of the slope,and the analysis method for the stability evolution considering the damage softening of the shear zone is lacking.In this study,the large deformation shear mechanical behavior of expansive soil was investigated by ring shear test.The damage softening characteristic of expansive soil in the shear zone was analyzed,and a shear damage model reflecting the damage softening behavior of expansive soil was derived based on the damage theory.Finally,by skillfully combining the vector sum method and the shear damage model,an analysis method for the stability evolution of the expansive soil slope considering the shear zone damage softening was proposed.The results show that the shear zone subjected to large displacement shear deformation exhibits an obvious damage softening phenomenon.The damage variable equation based on the logistic function can be well used to describe the shear damage characteristics of expansive soil,and the proposed shear damage model is in good agreement with the ring shear test results.The vector sum method considering the damage softening behavior of the shear zone can be well applied to analyze the stability evolution characteristics of the expansive soil slope.The stability factor of the expansive soil slope decreases with the increase of shear displacement,showing an obvious progressive failure behavior. 展开更多
关键词 Expansive soil slope Stability analysis Ring shear test Vector sum method Damage model Strain softening
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DIAGONALIZATION METHOD FOR A SINGULARLY PERTURBED VECTOR ROBIN PROBLEM 认领 引用
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作者 倪守平 《Applied Mathematics and Mechanics(English Edition)》 SCIE 1989年第4期329-336,共8页
In this paper the method and technique of the diagonalization are employed to transform a vector second-order nonlinear system into two first-order approximate diagonalized systems. The existence and the asymptotic be... In this paper the method and technique of the diagonalization are employed to transform a vector second-order nonlinear system into two first-order approximate diagonalized systems. The existence and the asymptotic behavior of the solutions are obtained for a vector second-order nonlinear Robin problem of singular perturbation type. 展开更多
关键词 DIAGONALIZATION METHOD FOR A SINGULARLY PERTURBED VECTOR ROBIN PROBLEM
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Casing life prediction using Borda and support vector machine methods 认领 引用 被引量：4
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作者 Xu Zhiqian Yan Xiangzhen Yang Xiujuan 《Petroleum Science》 SCIE CAS 2010年第3期416-421,共6页
Eight casing failure modes and 32 risk factors in oil and gas wells are given in this paper. According to the quantitative analysis of the influence degree and occurrence probability of risk factors, the Borda counts ... Eight casing failure modes and 32 risk factors in oil and gas wells are given in this paper. According to the quantitative analysis of the influence degree and occurrence probability of risk factors, the Borda counts for failure modes are obtained with the Borda method. The risk indexes of failure modes are derived from the Borda matrix. Based on the support vector machine （SVM）, a casing life prediction model is established. In the prediction model, eight risk indexes are defined as input vectors and casing life is defined as the output vector. The ideal model parameters are determined with the training set from 19 wells with casing failure. The casing life prediction software is developed with the SVM model as a predictor. The residual life of 60 wells with casing failure is predicted with the software, and then compared with the actual casing life. The comparison results show that the casing life prediction software with the SVM model has high accuracy. 展开更多
关键词 Support vector machine method Borda method life prediction model failure modes riskfactors
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Slope stability analysis under seismic load by vector sum analysis method 认领 引用 被引量：22
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作者 Mingwei Guo Xiurun Ge Shuilin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2011年第3期282-288,共7页
The vibration characteristics and dynamic responses of rock and soil under seismic load can be estimated with dynamic finite element method(DFEM).Combining with the DFEM,the vector sum analysis method(VSAM)is employed... The vibration characteristics and dynamic responses of rock and soil under seismic load can be estimated with dynamic finite element method(DFEM).Combining with the DFEM,the vector sum analysis method(VSAM)is employed in seismic stability analysis of a slope in this paper.Different from other conventional methods,the VSAM is proposed based on the vector characteristic of force and current stress state of the slope.The dynamic stress state of the slope at any moment under seismic load can he obtained by the DFEM,thus the factor of safety of the slope at any moment during earthquake can be easily obtained with the VSAM in consideration of the DFEM.Then,the global stability of the slope can be estimated on the basis of time-history curve of factor of safety and reliability theory.The VSAM is applied to a homogeneous slope under seismic load.The factor of safety of the slope is 1.30 under gravity only and the dynamic factor of safety under seismic load is 1.21.The calculating results show that the dynamic characteristics and stability state of the slope with input ground motion can be actually analyzed.It is believed that the VSAM is a feasible and practical approach to estimate the dynamic stability of slopes under seismic load. 展开更多
关键词 slope stability vector sum analysis method(VSAM) seismic load dynamic finite element method(DFEM)
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Novel Real-Time Seam Tracking Algorithm Based on Vector Angle and Least Square Method 认领 引用 被引量：1
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作者 Guanhao Liang Qingsheng Luo +1 位作者 Zhuo Ge Xiaoqing Guan 《Journal of Beijing Institute of Technology》 EI CAS 2017年第2期150-157,共8页
Real-time seam tracking can improve welding quality and enhance welding efficiency during the welding process in automobile manufacturing.However,the teaching-playing welding process,an off-line seam tracking method,i... Real-time seam tracking can improve welding quality and enhance welding efficiency during the welding process in automobile manufacturing.However,the teaching-playing welding process,an off-line seam tracking method,is still dominant in automobile industry,which is less flexible when welding objects or situation change.A novel real-time algorithm consisting of seam detection and generation is proposed to track seam.Using captured 3D points,space vectors were created between two adjacent points along each laser line and then a vector angle based algorithm was developed to detect target points on the seam.Least square method was used to fit target points to a welding trajectory for seam tracking.Furthermore,the real-time seam tracking process was simulated in MATLAB/Simulink.The trend of joint angles vs.time was logged and a comparison between the off-line and the proposed seam tracking algorithm was conducted.Results show that the proposed real-time seam tracking algorithm can work in a real-time scenario and have high accuracy in welding point positioning. 展开更多
关键词 real-time seam tracking real-time seam detection laser scanner vector angle leastsquare method algorithm research
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Dynamics of Quantum State and Effective Hamiltonian with Vector Differential Form of Motion Method 认领 引用
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作者 Long Xiong Wei-Feng Zhuang Ming Gong 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第7期36-40,共5页
Effective Hamiltonians in periodically driven systems have received widespread attention for realization of novel quantum phases, non-equilibrium phase transition, and Majorana mode. Recently, the study of effective H... Effective Hamiltonians in periodically driven systems have received widespread attention for realization of novel quantum phases, non-equilibrium phase transition, and Majorana mode. Recently, the study of effective Hamiltonian using various methods has gained great interest. We consider a vector differential equation of motion to derive the effective Hamiltonian for any periodically driven two-level system, and the dynamics of the spin vector are an evolution under the Bloch sphere. Here, we investigate the properties of this equation and show that a sudden change of the effective Hamiltonian is expected. Furthermore, we present several exact relations, whose expressions are independent of the different starting points. Moreover, we deduce the effective Hamiltonian from the high-frequency limit, which approximately equals the results in previous studies. Our results show that the vector differential equation of motion is not affected by a convergence problem, and thus, can be used to numerically investigate the effective models in any periodic modulating system. Finally, we anticipate that the proposed method can be applied to experimental platforms that require time-periodic modulation, such as ultracold atoms and optical lattices. 展开更多
关键词 Dynamics of Quantum State and Effective Hamiltonian with Vector Differential Form of Motion Method Hamiltonian Vector Quantum
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New regularization method and iteratively reweighted algorithm for sparse vector recovery 认领 引用 被引量：2
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作者 Wei ZHU Hui ZHANG Lizhi CHENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第1期157-172,共16页
Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector recovery.We derive sufficient conditions on the well-posedness of the new regularization,and design... Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector recovery.We derive sufficient conditions on the well-posedness of the new regularization,and design an iterative algorithm,namely the iteratively reweighted algorithm(IR-algorithm),for efficiently computing the sparse solutions to the proposed regularization model.The convergence of the IR-algorithm and the setting of the regularization parameters are analyzed at length.Finally,we present numerical examples to illustrate the features of the new regularization and algorithm. 展开更多
关键词 regularization method iteratively reweighted algorithm(IR-algorithm) sparse vector recovery
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Vector Dominating Multi-objective Evolution Algorithm for Aerodynamic-Structure Integrative Design of Wind Turbine Blade 认领 引用 被引量：1
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作者 Wang Long Wang Tongguang +1 位作者 Wu Jianghai Ke Shitang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第1期1-8,共8页
A novel multi-objective optimization algorithm incorporating vector method and evolution strategies,referred as vector dominant multi-objective evolutionary algorithm(VD-MOEA),is developed and applied to the aerodynam... A novel multi-objective optimization algorithm incorporating vector method and evolution strategies,referred as vector dominant multi-objective evolutionary algorithm(VD-MOEA),is developed and applied to the aerodynamic-structural integrative design of wind turbine blades.A set of virtual vectors are elaborately constructed,guiding population to fast move forward to the Pareto optimal front and dominating the distribution uniformity with high efficiency.In comparison to conventional evolution algorithms,VD-MOEA displays dramatic improvement of algorithm performance in both convergence and diversity preservation when handling complex problems of multi-variables,multi-objectives and multi-constraints.As an example,a 1.5 MW wind turbine blade is subsequently designed taking the maximum annual energy production,the minimum blade mass,and the minimum blade root thrust as the optimization objectives.The results show that the Pareto optimal set can be obtained in one single simulation run and that the obtained solutions in the optimal set are distributed quite uniformly,maximally maintaining the population diversity.The efficiency of VD-MOEA has been elevated by two orders of magnitude compared with the classical NSGA-II.This provides a reliable high-performance optimization approach for the aerodynamic-structural integrative design of wind turbine blade. 展开更多
关键词 wind turbine multi-objective optimization vector method evolution algorithm
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基于UV-UKF联合的5G高精度定位方法 认领 引用
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作者 潘树国 王健城 +3 位作者 陶贤露 高旺 赵庆 王强 《东南大学学报（自然科学版）》 EI CAS CSCD 北大核心 2026年第8期1229-1238,共10页
物联网时代5G技术的迅速发展为高精度室内外定位提供了重要的解决方案。然而,复杂多变环境下5G信号易受非线性、非视距误差影响,导致定位精度和可用性不足。为此,本文提出了一种单位向量(UV)和无迹卡尔曼滤波(UKF)联合的5G到达角(AOA)/... 物联网时代5G技术的迅速发展为高精度室内外定位提供了重要的解决方案。然而,复杂多变环境下5G信号易受非线性、非视距误差影响,导致定位精度和可用性不足。为此,本文提出了一种单位向量(UV)和无迹卡尔曼滤波(UKF)联合的5G到达角(AOA)/到达时间差(TDOA)混合定位方法。首先,基于后验残差分析与动态滑动窗口实现AOA观测误差自适应探测,并利用双基站差分消除TDOA基站间钟差。其次,针对常规角度观测方程的严重非线性误差影响,建立了AOA/TDOA信号混合的单位向量观测模型,通过雅可比矩阵条件数与克拉美罗下界(CRLB)分析,验证了该模型可显著降低观测方程的非线性程度。最后,通过UKF进一步提升了动态轨迹的平滑性。仿真和实测结果表明,UV-UKF方法的定位误差优于0.5 m,具备连续平滑的高精度定位能力。 展开更多
关键词 5G定位 AOA/TDOA观测 单位向量法 无迹卡尔曼滤波(UKF) 非线性误差
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用于NPA阶段的北斗机载接收机完好性适航符合性技术研究 认领 引用
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作者 刘瑞华 余澜涛 《航空工程进展》 CSCD 2026年第4期211-222,共12页
全球导航卫星系统(GNSS)相关适航标准与完好性适航测试流程并不完全适用于北斗机载设备。根据所需导航性能(RNP)中不同空域的完好性要求,结合航空无线电委员会(RTCA)等相关适航标准和工业标准,对Beta类北斗机载接收机完好性适航符合技... 全球导航卫星系统(GNSS)相关适航标准与完好性适航测试流程并不完全适用于北斗机载设备。根据所需导航性能(RNP)中不同空域的完好性要求,结合航空无线电委员会(RTCA)等相关适航标准和工业标准,对Beta类北斗机载接收机完好性适航符合技术进行研究。以加权奇偶矢量法作为接收机自主完好性监视(RAIM)理论基础,建立标准化测试环境,提出测试条件、测试方法、测试流程和适航符合性指标。测试使用检测和排除概率为10-3的无故障接收机接收2024年2月4日北斗B1C信号广播星历,针对北斗三号系统并基于非精密进近(NPA)阶段,在全球范围内进行静态和动态场景下的接收机自主完好性监测(RAIM)性能评估,并给出无故障接收机测试结果和适航符合性判据。研究成果可以为适用于非精密进近及以下运行阶段的北斗机载接收机完好性适航验证提供相应的理论和方法支持。 展开更多
关键词 完好性 适航符合性 北斗机载接收机 加权奇偶矢量法
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基于几何解析的平面并联机构运动学分析 认领 引用
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作者 杨光 张兴健 +2 位作者 杜惠斌 祁大伟 张宇翔 《中国工程机械学报》 北大核心 2026年第3期443-447,共5页
针对两自由度平面并联六连杆机构的运动学求解难题,本文提出一种基于几何解析的分析方法。首先基于机构构型特征建立运动简图,通过三角形分解法实现逆运动学的高效解析求解;采用矢量闭环法构建非线性方程组,结合牛顿-拉弗森迭代算法完... 针对两自由度平面并联六连杆机构的运动学求解难题,本文提出一种基于几何解析的分析方法。首先基于机构构型特征建立运动简图,通过三角形分解法实现逆运动学的高效解析求解;采用矢量闭环法构建非线性方程组,结合牛顿-拉弗森迭代算法完成正运动学的高精度数值求解。仿真验证表明:正运动学迭代收敛误差小于e-8,动平台位姿计算与SolidWorks仿真结果的最大相对误差不超过0.03%。该方法显著提升了计算效率与数值稳定性,为并联机构的实时控制提供了新的技术途径。 展开更多
关键词 平面并联机构 运动学分析 几何解析 牛顿-拉弗森迭代法 矢量闭环法
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SVD-MPE: An SVD-Based Vector Extrapolation Method of Polynomial Type 认领 引用 被引量：1
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作者 Avram Sidi 《Applied Mathematics》 2016年第11期1260-1278,共19页
An important problem that arises in different areas of science and engineering is that of computing the limits of sequences of vectors , where , N being very large. Such sequences arise, for example, in the solution o... An important problem that arises in different areas of science and engineering is that of computing the limits of sequences of vectors , where , N being very large. Such sequences arise, for example, in the solution of systems of linear or nonlinear equations by fixed-point iterative methods, and are simply the required solutions. In most cases of interest, however, these sequences converge to their limits extremely slowly. One practical way to make the sequences converge more quickly is to apply to them vector extrapolation methods. Two types of methods exist in the literature: polynomial type methods and epsilon algorithms. In most applications, the polynomial type methods have proved to be superior convergence accelerators. Three polynomial type methods are known, and these are the minimal polynomial extrapolation (MPE), the reduced rank extrapolation (RRE), and the modified minimal polynomial extrapolation (MMPE). In this work, we develop yet another polynomial type method, which is based on the singular value decomposition, as well as the ideas that lead to MPE. We denote this new method by SVD-MPE. We also design a numerically stable algorithm for its implementation, whose computational cost and storage requirements are minimal. Finally, we illustrate the use of SVD-MPE with numerical examples. 展开更多
关键词 Vector Extrapolation Minimal Polynomial Extrapolation Singular Value Decomposition Krylov Subspace Methods
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奶牛个体瘤胃碳排放量在线检测装备设计与试验 认领 引用
20
作者 赵文文 王海峰 +3 位作者 朱君 王志彬 郭刚 李斌 《农业机械学报》 EI CAS CSCD 北大核心 2026年第8期386-396,426,共11页
发展奶牛个体瘤胃碳排放在线检测技术对于推动畜牧业减排降碳、实现持续高质量发展具有重要意义。针对我国奶牛养殖个体瘤胃碳排放检测/监测流程繁琐、效率低、适用装备缺乏等问题,设计了一种奶牛个体瘤胃碳排放在线检测装备,并提出了... 发展奶牛个体瘤胃碳排放在线检测技术对于推动畜牧业减排降碳、实现持续高质量发展具有重要意义。针对我国奶牛养殖个体瘤胃碳排放检测/监测流程繁琐、效率低、适用装备缺乏等问题,设计了一种奶牛个体瘤胃碳排放在线检测装备,并提出了基于支持向量机(SVM)的奶牛个体日碳排放量预测模型。以STM32微处理器为主控制核心,集成RFID/甲烷/二氧化碳等传感器采集数据,采用LoRa/4G双模通信技术传输数据,基于Qt Creator软件/云平台分析与显示数据,实现奶牛个体碳排放数据本地/远程一体化监测、传输、分析与可视化显示。采用背景浓度扣除法与时间点对齐重构方式,构建了基于SVM的奶牛个体碳排放预测模型,实现浓度数据到奶牛个体碳排放量准确测算。在北京某牧场对25头荷斯坦奶牛进行了实地测试,与二氧化碳平衡法相比,基于SVM回归预测模型的奶牛平均日二氧化碳排放量、甲烷排放量、碳排放量MAE平均值分别为511.13、58.16、2 202.10 g/d;MRE平均值分别为3.78%、14.34%、8.55%;在牛舍打开风机情况下,SVM预测奶牛个体平均二氧化碳排放量、甲烷排放量、碳排放量波动幅度分别为10.85、8.15、255.35 g/d,均显著低于二氧化碳平衡法对应差值。研究结果能够实现奶牛个体瘤胃甲烷和二氧化碳排放量实时、快速、准确测定,可为农牧业碳排放量精准核算提供技术参考。 展开更多
关键词 奶牛个体 瘤胃 碳排放 在线检测 支持向量机 二氧化碳平衡法
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