期刊文献+
共找到2,593篇文章
< 1 2 130 >
每页显示 20 50 100
Representation of the ENSO Combination Mode and its Asymmetric SST Response in Different Resolutions of HadGEM3
1
作者 Jianghua WAN Hongli REN Peili WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第8期167-180,共14页
Previous studies have revealed a combination mode (C-mode) occurring in the Indo-Pacific region, arising from nonlinear interactions between ENSO and the western Pacific warm pool annual cycle. This paper evaluates ... Previous studies have revealed a combination mode (C-mode) occurring in the Indo-Pacific region, arising from nonlinear interactions between ENSO and the western Pacific warm pool annual cycle. This paper evaluates the simulation of this C-mode and its asymmetric SST response in HadGEM3 and its resolution sensitivity using three sets of simulations at horizontal resolutions of N96, N216 and N512. The results show that HadGEM3 can capture well the spatial pattern of the C-mode associated surface wind anomalies, as well as the asymmetric response of SST in the tropical Pacific, but it strongly overestimates the explained variability of the C-mode compared to the ENSO mode. The model with the three resolutions is able to reproduce the distinct spectral peaks of the C-mode at the near annual combination frequencies, but the performance in simulating the longer periods is not satisfactory, presumably due to the unrealistic simulation of the ENSO mode. Increasing the horizontal resolution can improve the consistency between atmospheric and oceanic representations of the C-mode, but not necessarily enhance the accuracy of C-mode simulation compared with observation. 展开更多
关键词 ENSO combination mode asymmetric response Nifio-A index HadGEM3 horizontal resolution
在线阅读 下载PDF
Research on the Combination Mode of Modem Product and Industrial Design under the Green Design Background
2
作者 Liying Wu 《International Journal of Technology Management》 2016年第3期57-59,共3页
In this paper, we conduct research on the combination mode of the modern product and the industrial design under the green design background. Our enterprises must set up the industrial design as the basis of the new m... In this paper, we conduct research on the combination mode of the modern product and the industrial design under the green design background. Our enterprises must set up the industrial design as the basis of the new mechanism, treatment of product, enterprise and market to trinity, cannot be indifferent to a certain aspect, to every aspect, to attach importance to technology, hard management talents, on the basis of industrial designers should play the role of soft energetically. Industrial design should have good adhesive property, product, enterprise and market more harmonious, more closely linked, creation of the technical performance, reasonable internal structure, a novel appearance, low production cost, a profound cultural products, for the enterprise to bring the most lucrative business profits, and make the market more prosperous more standardized. Under this background, we propose the novel combination pattern that holds special meaning. 展开更多
关键词 combination mode Product and Industrial Design Green Design Trend.
在线阅读 下载PDF
An improved conditional denoising diffusion GAN for Mach number field reconstruction in a multi-tunnel combined inlet based on sparse parameter information
3
作者 Ke MIN Fan LEI +2 位作者 Jiale ZHANG Chengxiang ZHU Yancheng YOU 《Chinese Journal of Aeronautics》 2026年第1期169-190,共22页
The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To... The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To develop an efficient flow field reconstruction model for this,we present an Improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN),which integrates Conditional Denoising Diffusion Probabilistic Models(CDDPMs)with Style GAN,and introduce a reconstruction discrimination mechanism and dynamic loss weight learning strategy.We establish the Mach number flow field dataset by numerical simulation at various backpressures for the mode transition process from turbine mode to ejector ramjet mode at Mach number 2.5.The proposed ICDDGAN model,given only sparse parameter information,can rapidly generate high-quality Mach number flow fields without a large number of samples for training.The results show that ICDDGAN is superior to CDDGAN in terms of training convergence and stability.Moreover,the interpolation and extrapolation test results during backpressure conditions show that ICDDGAN can accurately and quickly reconstruct Mach number fields at various tunnel slice shapes,with a Structural Similarity Index Measure(SSIM)of over 0.96 and a Mean-Square Error(MSE)of 0.035%to actual flow fields,reducing time costs by 7-8 orders of magnitude compared to Computational Fluid Dynamics(CFD)calculations.This can provide an efficient means for rapid computation of complex flow fields. 展开更多
关键词 Flow field reconstruction Improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN) mode transition Sparse parameter information Three-dimensional inward-tunning combined inlet
原文传递
Combined model of trip mode and destination 被引量:1
4
作者 姜雨 陆键 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期633-637,共5页
This paper analyzes the characteristics of the destination distribution of trips and proposes a stratified sampling strategy for travel mode choice.The stratified sampling strategy can reduce the size of the alternati... This paper analyzes the characteristics of the destination distribution of trips and proposes a stratified sampling strategy for travel mode choice.The stratified sampling strategy can reduce the size of the alternative set;thus,the computation burden of simulation is decreased.Using the stratified sampling strategy,a combined choice model of the trip mode and destination is developed based on the Bayesian theory.Simulations are carried out to verify the proposed model.The results show that the combined choice model of the trip mode and destination can efficiently simulate travelers' choice behaviors.Furthermore,the forecasting accuracy of the combined choice model is higher than the one of the gravity model.Therefore,the proposed model is a powerful tool with which to analyze travelers' behaviors in selecting the trip mode. 展开更多
关键词 combined choice model discrete choice trip mode and destination sampling
在线阅读 下载PDF
An improved displacement-based adaptive pushover procedure based on factor modal combination rule 被引量:2
5
作者 Abbasnia R Tajik Davoudi A Maddah M.M 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第2期223-241,共19页
An accurate estimation of the applied load pattern is an essential component in each pushover procedure. Recently, a number of adaptive pushover methods have been proposed in which the effects of the higher modes as w... An accurate estimation of the applied load pattern is an essential component in each pushover procedure. Recently, a number of adaptive pushover methods have been proposed in which the effects of the higher modes as well as the progressive changes in the dynamic characteristics of structures are taken into account to compute the applied load pattern. The basic shortcoming of these advanced pushover methods is related to employing the quadratic modal combination rule, whereby the sign reversals of the modal load vectors are suppressed. In this study, an improved displacement-based adaptive pushover method is developed in which the applied load pattern is computed using the factor modal combination rule(FMC). In the proposed procedure, multiple load patterns, depending on the number of the modes considered, are determined in order to take into account the sign reversals of different modal load vectors. The accuracy of the proposed method is verifi ed for seven moment resisting frame buildings of 3, 9 and 20 stories with regularity or vertically geometric and mass irregularities subjected to 60 earthquake ground motion records. The results showed that the proposed methodology is capable of reproducing the peak dynamic responses with very good accuracy. 展开更多
关键词 adaptive pushover higher modes sign reversal factor modal combination rule
在线阅读 下载PDF
A HALF PLANE CRACK UNDER THREE-DIMENSIONAL COMBINED MODE IMPACT LOADING 被引量:1
6
作者 柳春图 李湘平 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1994年第1期40-48,共9页
The dynamic stress intensity factor history for a half plane crack in an otherwise unbounded elastic body, with the crack faces subjected to a traction distribution consisting of two pairs of suddenly-applied shear li... The dynamic stress intensity factor history for a half plane crack in an otherwise unbounded elastic body, with the crack faces subjected to a traction distribution consisting of two pairs of suddenly-applied shear line loads is consid- ered. The analytic expression for the combined mode stress intensity factors as a function of time is obtained. The method of solution is based on the application of integral transforms and the Wiener-Hopf technique. Some features of the solutions are discussed and graphical numerical results are presented. 展开更多
关键词 impact line loads a half plane crack combined mode dynamic stress intensity factor
在线阅读 下载PDF
A solution strategy combining the mode superposition method and time integration methods for linear dynamic systems
7
作者 Yufeng Xing Lu Yao Yi Ji 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第6期167-181,I0004,共16页
In this article,the mode superposition method is combined with a time integration method like the trapezoidal rule to improve solution accuracy for linear dynamic systems.In this combination strategy,the essential thi... In this article,the mode superposition method is combined with a time integration method like the trapezoidal rule to improve solution accuracy for linear dynamic systems.In this combination strategy,the essential thing is to decompose a dynamic system into two sub-systems,a small-scale low-frequency system and a high-frequency system.The former can be analytically and efficiently solved with the mode superposition method,and the latter is dealt with through a time integration method such as the Newmark method.The summation of the responses of these two sub-systems is the responses of the original dynamic system.It is concluded that,with little sacrifice of efficiency,the combination method based on the strategy is more accurate than the combined time integration method,but it has the same accuracy order as that of the combined method.Numerical experiments validate the effectiveness of the proposed strategy. 展开更多
关键词 mode superposition method Time integration method ACCURACY combination
原文传递
Adaptive configuration control of combined UAVs based on leader-wingman mode
8
作者 Rui HUANG Hanlin SHENG +4 位作者 Qian CHEN Ziting RAN Zhen XUE Jiacheng LI Tong LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第12期416-433,共18页
Modular Unmanned Aerial Vehicles(UAVs)can adapt to rapidly changing payload requirements based on the shape and weight of the load by adding or subtracting units,reconfiguring,or changing the type of units.The existin... Modular Unmanned Aerial Vehicles(UAVs)can adapt to rapidly changing payload requirements based on the shape and weight of the load by adding or subtracting units,reconfiguring,or changing the type of units.The existing research has addressed aerial docking and hover control post-docking but fails to achieve coordinated flight following combination,leading to delayed response and oscillations as the number of UAV units increases.Moreover,the configuration of modular UAVs is complex and variable,making it challenging to adjust the controller parameters of each unit online.Therefore,this paper presents:(A)Adaptive attitude allocation method for different combined UAV configurations:establishing a mapping relationship between constant controller parameters of the unit and the combination angular acceleration.The desired torque of the combination is allocated based on the size of the lever arm,enabling adaptive attitude control of the combination for varying configurations by controlling the attitude of the local unit;(B)A power allocation strategy based on a leader-wingman mode:employing a leader to control the entire combination,distributing the combination’s force and torque to wingman units according to the mapping relationship of the attitude allocation method.This transforms the complex control of the combination into unit control in the leader-wingman mode.Compared to current average allocation methods,the step response of attitude angle improves by about 60% on average,and spatial trajectory tracking increases by an average of 11.5%.As the number of units grows,the response of the combination becomes similar to that of a single,independently flying UAV,resolving the oscillation issue in combined flight.Additionally,this approach eliminates the need to change the controller parameters of all units,facilitating convenient reconfiguration and coordinated flight for modular UAVs post-combination. 展开更多
关键词 Unmanned aerial vehicle combined UAVs control Modular UAVs control Leader-wingman mode Adaptive attitude allocation Power allocation
原文传递
Generation/collection mode of SECM with combined probe
9
作者 Wei Wang Jie Zhang +2 位作者 LianHuan Han DeZhi Yang Dong Ping Zhan 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第1期86-88,共3页
Here we report a novel generation/collection operation mode of scanning electrochemical microscopy,in which a theta micropipette was employed to support two adjacent water/1,2-dichloroethane interfaces separated by th... Here we report a novel generation/collection operation mode of scanning electrochemical microscopy,in which a theta micropipette was employed to support two adjacent water/1,2-dichloroethane interfaces separated by the thin central glass wall:one acts as the generator while the other as the collector.The generation current,collection current and collection efficiency were enhanced significantly when the tip approached to an insulate substrate. 展开更多
关键词 SECM Generation/collection mode combined probe
原文传递
A New Fracture Criterion for a Crack under Combined Mode Loading
10
作者 周小平 王建华 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第1期89-91,共3页
A new fracture criterion was proposed. The physical explanation of the criterion is that crack will propagate when the minimum strain energy density in iso hoop stress curve reach a critical strength of the material c... A new fracture criterion was proposed. The physical explanation of the criterion is that crack will propagate when the minimum strain energy density in iso hoop stress curve reach a critical strength of the material considered. The resulting curve of critical fracture of mixed mode cracks shows that the present fracture is efficient and more accurate than the previous criteria. 展开更多
关键词 fracture criterion combined mode loading minimum strain energy density in iso hoop stress curve
在线阅读 下载PDF
Research on the path of medical service combination from the perspective of departmental cooperation
11
作者 YANG Huazhen 《International English Education Research》 2018年第3期59-61,共3页
As an innovative mode of social endowment, combining medical care with modern medical care technology and old-age service is an important direction of a series of social problems caused by the deepening of aging and t... As an innovative mode of social endowment, combining medical care with modern medical care technology and old-age service is an important direction of a series of social problems caused by the deepening of aging and the intensification of aging process in China. It is the inevitable choice for the development of Chinese characteristics for the aged. At present, with the continuous development of the combination of medical care and rehabilitation, the process of combination of medical care and breeding is slow, and the problems of inter departmental cooperation, high cost of resource integration and low service efficiency have emerged. The paper puts forward that multi head management of different responsibility management body is a bottleneck problem that hinders the integration of medical care. From the objective and subjective two points of view, the administrative system level barrier and the inter departmental interest game are the important reasons that obstruct the medical support and break through the estrangement of the Department and realize the cooperation. Then, according to the theory of large part system reform, the author boldly proposes the idea of establishing a new comprehensive functional department that specializes in the management of pension related affairs. 展开更多
关键词 medical service combination new pension service mode department cooperation bottleneck problem
在线阅读 下载PDF
Research on the Application of Appropriate Technology of Traditional Chinese Medicine in the Mode of Combining Medical Care with Nursing Care for the Aged
12
作者 HUYalan LUSijie 《外文科技期刊数据库(文摘版)医药卫生》 2022年第5期180-184,共5页
With the aggravation of the aging population in China, the number of the elderly is increasing year by year due to the negative growth of the population. Healthy old-age care has become a realistic social problem, whi... With the aggravation of the aging population in China, the number of the elderly is increasing year by year due to the negative growth of the population. Healthy old-age care has become a realistic social problem, which needs to be solved urgently. At present, the mode of combining medical care with nursing care is being gradually implemented and applied all over the world. With its traditional Chinese medicine therapy, convenient and simple operation, safe and no side effects, the appropriate technology of traditional Chinese medicine gives full play to the unique advantages of Chinese medicine, and its application in the mode of combining medical care with nursing care can provide reference for the elderly. Based on this, this paper analyzes and studies the application of appropriate technology of traditional Chinese medicine in the mode of combining medical care with nursing care for the aged. 展开更多
关键词 appropriate technology of traditional Chinese medicine combination of medical care and nutrition pension mode application research
暂未订购
The reform of higher mathematics education pattern with the combination of experiment teaching
13
作者 Zhang Lihua 《Journal of Zhouyi Research》 2014年第1期64-66,共3页
关键词 高等数学教育 实验教学 教育模式 改革 高等数学教学 信息技术 数学实验 作者分析
在线阅读 下载PDF
Non-singular fast terminal sliding mode control for roll-pitch seeker based on extended state observers
14
作者 XIAO Bowen XIA Qunli 《Journal of Systems Engineering and Electronics》 2025年第2期537-551,共15页
For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode contr... For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode control method, aimed at resolving the frame control problem of roll-pitch seeker tracking high maneu-vering target. The sliding mode surface is structured around the principle of segmentation, which enables the control system’s rapid attainment of the zero point and ensure global fast conver-gence. The system’s state is more swiftly converged to the slid-ing mode surface through an improved adaptive fast dual power reaching law. Utilizing an extended state observer, the overall disturbance is both identified and compensated. The validation of the system’s stability and its convergence within a finite-time is grounded in Lyapunov’s stability criteria. The performance of the introduced control method is confirmed through roll-pitch seeker tracking control simulation. Data analysis reveals that newly proposed control technique significantly outperforms existing sliding mode control methods by rapidly converging the frame to the target angle, reduce the tracking error of the detec-tor for the target, and bolster tracking precision of the roll-pitch seeker huring disturbed conditions. 展开更多
关键词 air-to-air missile roll-pitch seeker finite-time con-vergence combined sliding mode control extended state observer
在线阅读 下载PDF
面向压力调控的液粘离合器滑膜控制器设计
15
作者 赵国亮 牛保顺 《拖拉机与农用运输车》 2026年第2期101-103,共3页
由于液粘离合器存在非线性和多变特征,传统滑模控制难以满足精度的要求,为此设计了一种面向压力调控的液粘离合器滑膜控制器。通过泵阀串联方式进行联合控制策略,利用变频驱动技术来精准调控油腔压力,通过调节液压泵供油量在油压腔内形... 由于液粘离合器存在非线性和多变特征,传统滑模控制难以满足精度的要求,为此设计了一种面向压力调控的液粘离合器滑膜控制器。通过泵阀串联方式进行联合控制策略,利用变频驱动技术来精准调控油腔压力,通过调节液压泵供油量在油压腔内形成目标压力,实现压力参数的精确匹配。研究结果表明:滑模控制下的控制过程存在跳变,引起系统运行过程的不稳定波动;泵阀联控下,对输入数据的剧烈抖动起到了较好抑制,且大幅改善了传统滑模控制中输入数据剧烈抖动的问题。该研究对提高汽车的控制精度以及效率具有一定的理论指导。 展开更多
关键词 液粘离合器 泵阀联合 滑模控制 控制策略
在线阅读 下载PDF
CEEMDAN和LSTM组合的高层建筑形变预测
16
作者 罗时龙 张巧娟 +3 位作者 李荣恒 李磊 丁旭东 刘兴涛 《合肥工业大学学报(自然科学版)》 北大核心 2026年第3期426-432,共7页
针对高层建筑形变监测时间序列非线性、非平稳性导致的预测精度较低的问题,文章提出一种基于自适应噪声完备集合经验模态分解(complete ensemble empirical mode decomposition with adaptive noise,CEEMDAN)与长短期记忆网络(long shor... 针对高层建筑形变监测时间序列非线性、非平稳性导致的预测精度较低的问题,文章提出一种基于自适应噪声完备集合经验模态分解(complete ensemble empirical mode decomposition with adaptive noise,CEEMDAN)与长短期记忆网络(long short-term memory,LSTM)的形变预测组合模型。首先对高层建筑形变监测数据进行CEEMDAN分解,得到有限个本征模态函数(intrinsic mode function,IMF)和趋势项,然后使用LSTM分别对其进行预测,最后重构得到可用的形变预测结果,利用模拟数据与实测数据进行验证,通过多种指标评定预测精度。结果表明,与单一LSTM模型和EMD-LSTM模型相比,CEEMDAN-LSTM模型能够更好地应对非线性、非平稳性特征,评价指标表现更优,特别对于70s预测时长,均方根误差(root mean square error,RMSE)、平均绝对误差(mean absolute error,MAE)、平均绝对百分比误差(mean absolute percentage error,MAPE)指标至少分别降低43%、50%、64%,显著提高预测精度。 展开更多
关键词 高层建筑 形变预测 组合模型 自适应噪声完备集合经验模态分解(CEEMDAN) 长短期记忆网络(LSTM)
在线阅读 下载PDF
基于RIME-VMD联合小波阈值的爆破振动信号去噪方法
17
作者 王薇 程忠耀 +1 位作者 向延念 宋良俊 《铁道科学与工程学报》 北大核心 2026年第1期465-479,共15页
随着现代化建设的加速推进,邻近既有建筑的爆破作业日益增多,监测和分析爆破引起的振动对结构安全的评估至关重要。然而,爆破振动信号的非线性特性和复杂的环境因素干扰使得从实测信号中提取有效信号成分难度较大,给后续的信号分析造成... 随着现代化建设的加速推进,邻近既有建筑的爆破作业日益增多,监测和分析爆破引起的振动对结构安全的评估至关重要。然而,爆破振动信号的非线性特性和复杂的环境因素干扰使得从实测信号中提取有效信号成分难度较大,给后续的信号分析造成了较大影响。为提高爆破振动信号的降噪精度,将雾凇优化算法(RIME)、变分模态分解(VMD)和小波阈值进行融合,形成一种爆破振动信号联合去噪方法。该方法首先通过雾凇优化算法对VMD关键参数进行优化,然后通过优化后的VMD对振动信号进行自适应分解,剔除方差贡献率较低的分量,再采用小波阈值对筛选后的分量进行降噪处理,最终重构得到去噪后的信号。对该方法的降噪效果进行仿真分析和实际工程验证,结果表明:在仿真信号分析中,经RIME-VMD联合小波阈值的降噪方法去噪后的信号与无噪声的纯净信号相比,形状与特征高度吻合,且信噪比(SNR)和均方根误差(RMSE)等去噪指标优于EMD、小波阈值、EMD联合小波阈值等常用去噪方法;经工程实际案例验证,该方法能够在极大保留原信号基本特征的前提下,有效去除爆破振动信号中的高频噪声,降噪后信号更加符合爆破振动信号的主频范围,且具有比EMD、小波阈值、EMD联合小波阈值等常用去噪方法更好的去噪效果。该研究成果对爆破振动信号的降噪处理具有参考意义。 展开更多
关键词 爆破振动 信号处理 联合降噪 雾凇优化算法 变分模态分解 小波阈值去噪
在线阅读 下载PDF
泵阀联控锚杆钻机回转马达转速研究
18
作者 高有山 唐光伟 +2 位作者 闫政 张梦圆 孙浩然 《机床与液压》 北大核心 2026年第1期119-126,共8页
针对锚杆钻机在复杂煤巷钻锚支护作业中,因围岩性状多变导致马达转速调节不及时而引起的钻头磨损与卡钻问题,提出一种泵阀联合控制策略,并构建泵阀联合控制系统。在阀控部分,针对回转系统的非线性和未建模扰动,设计改进型滑模自抗扰控制... 针对锚杆钻机在复杂煤巷钻锚支护作业中,因围岩性状多变导致马达转速调节不及时而引起的钻头磨损与卡钻问题,提出一种泵阀联合控制策略,并构建泵阀联合控制系统。在阀控部分,针对回转系统的非线性和未建模扰动,设计改进型滑模自抗扰控制器(SM-ADRC),利用扩张状态观测器估计并补偿系统总扰动,结合改进的趋近律滑模控制提高响应性和鲁棒性。在泵控部分,伺服电动机转速环采用一阶线性自抗扰控制(LADRC)以提升启动快速性和抗扰能力。为实现动力源与负载的流量匹配,引入基于灰色预测的负载流量预测模型,动态调节伺服电动机转速。此外,在系统中增设蓄能器以补偿负载突变时的流量需求。通过AMESim与Simulink搭建联合仿真模型,并在两种典型工况(围岩硬度系数突变、瞬时负载扰动)下与PID控制策略进行对比验证。结果表明:基于负载流量预测的泵控系统能使绝大部分输出流量用于负载马达回转,稳压阀溢流仅占5.82%,实现了流量的高效利用;在阀控部分,改进型SM-ADRC在围岩硬度系数由f=4突变至f=8时,马达转速超调量小于PID控制,调整时间略长但综合控制性能更优;在f=6工况下施加18 N·m瞬时扰动时,SM-ADRC控制的马达转速波动更小,稳定时间较PID控制缩短6.4%;在泵控部分,LADRC相较于PID控制使电动机转速响应时间减少10.6%,超调量降低1.8%;蓄能器有效平抑了系统压力和流量冲击,并在负载突变时快速补充流量,提升了系统动态响应能力。 展开更多
关键词 泵阀联控 改进型滑模自抗扰控制 马达回转速度 锚杆钻机
在线阅读 下载PDF
基于组合预测模型的风电短期出力场景生成方法
19
作者 冉华军 杨杰飞 +1 位作者 董家豪 黄显 《现代电子技术》 北大核心 2026年第8期114-120,127,共8页
在高可再生能源渗透率背景下,受天气混沌系统影响,风电出力的间歇性与波动性对电力系统运行、规划及控制构成挑战。可再生能源出力预测及场景生成法是应对新能源出力不确定性的有效手段,基于此,提出一种基于ALA-VMDiTransformer模型的... 在高可再生能源渗透率背景下,受天气混沌系统影响,风电出力的间歇性与波动性对电力系统运行、规划及控制构成挑战。可再生能源出力预测及场景生成法是应对新能源出力不确定性的有效手段,基于此,提出一种基于ALA-VMDiTransformer模型的风电短期出力场景生成方法。首先,利用人工旅鼠算法(ALA)优化变分模态分解(VMD)的关键参数,分解风电出力序列以提取多频段特征;再通过iTransformer模型深度转换与融合特征预测出力并计算误差;其次,基于正态分布构建概率模型,结合蒙特卡洛法生成涵盖多气象条件的场景集,采用概率距离场景削减法简化场景以提升可靠性;再次,从场景集对实际出力的描述精确性出发设置评估指标;最后,利用西北某风电场实际数据开展算例分析,对比LSTM、iTransformer、VMD-iTransformer等模型及传统场景生成法,验证所提方法的有效性与可靠性。结果表明:所提出的ALA-VMDiTransformer方法展现出更强的鲁棒性,在风电出力预测中具有综合性能优势;且相较于传统场景生成方法,改进场景生成方法可实现更高的覆盖率和更低的误差水平。 展开更多
关键词 风电出力预测 场景生成 人工旅鼠算法 变分模态分解 iTransformer模型 组合预测 蒙特卡洛法
在线阅读 下载PDF
大型发电机组合型接地方式及接地故障定位研究
20
作者 桂林 张琦雪 《水电与抽水蓄能》 2026年第1期42-51,63,I0003,I0004,共13页
大型发电机中性点接地方式的争论由来已久,争论的焦点在于定子接地故障安全电流值的确定依据和100%定子接地保护的实现方式。本文介绍了对于上述问题的解决方案——对于高阻接地方式而言,应在定子铁芯烧损试验研究和仿真分析的基础上,... 大型发电机中性点接地方式的争论由来已久,争论的焦点在于定子接地故障安全电流值的确定依据和100%定子接地保护的实现方式。本文介绍了对于上述问题的解决方案——对于高阻接地方式而言,应在定子铁芯烧损试验研究和仿真分析的基础上,通过组合型接地方式的优化设计来补偿发电机固有电容电流的增大,限制接地故障电流为15~25A,并结合定子接地故障定位精度的提高来降低故障检修的难度;对于消弧线圈接地方式,则是利用或重新设计其串接电阻来注入20Hz信号,实现100%定子接地保护,因为该接地方式下不存在铁芯烧损问题。上述研究成果已被《继电保护和安全自动装置技术规程》(GB/T 14285—2023)所采纳,并将为后续大电站的建设和技术改造工作提供借鉴。 展开更多
关键词 大型发电机 定子接地故障安全电流值 组合型接地方式 接地故障定位 注入式定子接地保护
在线阅读 下载PDF
上一页 1 2 130 下一页 到第
使用帮助 返回顶部