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New Mathematical Model Based on Affine ransformation for Remote Sensing Image with High Resolution
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作者 ZHANG Jianqing ZHANG Zuxun 《Geo-Spatial Information Science》 2003年第1期49-53,共5页
This paper calculates the parameters of image position and orientation,proposes a mathematical model and adopts a new method with three steps of transformations based on parallel ray projection.Every step of the model... This paper calculates the parameters of image position and orientation,proposes a mathematical model and adopts a new method with three steps of transformations based on parallel ray projection.Every step of the model is strict,and the map function of each transformation is the first order polynomials and other simple function.The final calculation of the parameters is for the linear equations with good status.As a result,the problem of the relativity of image parameter calculation is solved completely.Some experiments are carried out. 展开更多
关键词 remote sensing image high resolution parameter calculation affine transformation mathematical model
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Multiple Model Soft Sensor Based on Affinity Propagation, Gaussian Process and Bayesian Committee Machine 被引量:32
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作者 李修亮 苏宏业 褚健 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第1期95-99,共5页
Presented is a multiple model soft sensing method based on Affinity Propagation (AP), Gaussian process (GP) and Bayesian committee machine (BCM). AP clustering arithmetic is used to cluster training samples acco... Presented is a multiple model soft sensing method based on Affinity Propagation (AP), Gaussian process (GP) and Bayesian committee machine (BCM). AP clustering arithmetic is used to cluster training samples according to their operating points. Then, the sub-models are estimated by Gaussian Process Regression (GPR). Finally, in order to get a global probabilistic prediction, Bayesian committee mactnne is used to combine the outputs of the sub-estimators. The proposed method has been applied to predict the light naphtha end point in hydrocracker fractionators. Practical applications indicate that it is useful for the online prediction of quality monitoring in chemical processes. 展开更多
关键词 multiple model soft sensor affinity propagation Gaussian process Bayesian committee machine
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基于Affine强度的一般Poisson损失动态模型 被引量:2
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作者 韩丹 张效成 《天津理工大学学报》 2007年第6期75-78,共4页
首先介绍了GPL动态模型,然后引入Affine过程的概念,讨论随机强度是Affine过程时的GPL模型,并进一步讨论了如何求出随机过程的损失密度,从而得出CDO债券的价格.
关键词 GPL动态模型 POISSON过程 affine过程 affine强度 损失密度
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3D Model Retrieval Method Based on Affinity Propagation Clustering 被引量:2
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作者 Lin Lin Xiao-Long Xie Fang-Yu Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第3期12-21,共10页
In order to improve the accuracy and efficiency of 3D model retrieval,the method based on affinity propagation clustering algorithm is proposed. Firstly,projection ray-based method is proposed to improve the feature e... In order to improve the accuracy and efficiency of 3D model retrieval,the method based on affinity propagation clustering algorithm is proposed. Firstly,projection ray-based method is proposed to improve the feature extraction efficiency of 3D models. Based on the relationship between model and its projection,the intersection in 3D space is transformed into intersection in 2D space,which reduces the number of intersection and improves the efficiency of the extraction algorithm. In feature extraction,multi-layer spheres method is analyzed. The two-layer spheres method makes the feature vector more accurate and improves retrieval precision. Secondly,Semi-supervised Affinity Propagation ( S-AP) clustering is utilized because it can be applied to different cluster structures. The S-AP algorithm is adopted to find the center models and then the center model collection is built. During retrieval process,the collection is utilized to classify the query model into corresponding model base and then the most similar model is retrieved in the model base. Finally,75 sample models from Princeton library are selected to do the experiment and then 36 models are used for retrieval test. The results validate that the proposed method outperforms the original method and the retrieval precision and recall ratios are improved effectively. 展开更多
关键词 feature extraction project ray-based method affinity propagation clustering 3D model retrieval
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High-frequency acoustic backscattering characteristics for acoustic detection of the red tide species Akashiwo sanguinea and Alexandrium affine 被引量:1
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作者 KIM Hansoo KANG Donhyug +1 位作者 JUNG Seung Won KIM Mira 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第4期1268-1276,共9页
Harmful algal blooms (HABs), caused by the overgrowth of certain phytoplankton species, have negative effects on marine environments and coastal fisheries. In addition to cell-counting methods using phytoplankton nets... Harmful algal blooms (HABs), caused by the overgrowth of certain phytoplankton species, have negative effects on marine environments and coastal fisheries. In addition to cell-counting methods using phytoplankton nets, a hydroacoustic technique based on acoustic backscattering has been proposed for the detection of phytoplankton blooms. However, little is known of the acoustic properties of HAB species. In this study, as essential data to support this technique, we measured the acoustic properties of two HAB species, Akashiwo sanguinea and Alexandrium affine, which occur in the South Sea off the coast of Korea. Due to the small size of the target, we used ultrasound for the measurements. Experiments were conducted under laboratory and field conditions. In the laboratory experiment, the acoustic signal received from each species was directly proportional to the cell abundance. We derived a relationship between the cell abundance and acoustic signal received for each species. The measured signals were compared to predictions of a fluid sphere scattering model. When A. sanguinea blooms appeared at an abundance greater than 3 500 cells/mL, the acoustic signals varied with cell abundance, showing a good correlation. These results confirm that acoustic measurements can be used to detect HAB species. 展开更多
关键词 acoustic backscattering Akashiwo sanguinea ALEXANDRIUM affine fluid-sphere scattering model harmful ALGAL BLOOMS (HABs) red TIDE
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基于affine类时频分析的旋回性薄互层时频特征影响因素分析 被引量:1
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作者 聂伟东 李雪英 +2 位作者 万乔升 王福霖 何谞超 《物探与化探》 CAS 北大核心 2020年第4期763-769,共7页
affine类时频分析方法具有模糊瞬时频谱变化细节,突出主要频率变化趋势的特点,具有较好的旋回判别能力,因而被学者用于旋回性薄互层类型判别当中,研究发现,旋回性薄互层时域波形均有向薄层方向波形密集,厚层方向波形稀疏的特点,但其稳... affine类时频分析方法具有模糊瞬时频谱变化细节,突出主要频率变化趋势的特点,具有较好的旋回判别能力,因而被学者用于旋回性薄互层类型判别当中,研究发现,旋回性薄互层时域波形均有向薄层方向波形密集,厚层方向波形稀疏的特点,但其稳定性差,易受外界干扰影响。由仿射类时频分布得到的时频谱与沉积旋回模式具有一一对应关系,不同模式旋回薄互层均有向层厚减薄方向的升频特点,目前关于旋回性薄互层时频特征影响因素的研究很少,厘清这些因素对旋回判断准则的影响有重要的意义。基于以上考虑,本文以正旋回模型为基础,从小层厚度突变、波阻抗大小、噪声影响、地震资料主频大小、地层黏性吸收作用等5个方面对旋回判别的影响进行了探讨。首先根据波动理论,利用深度域相移法对不同影响因素条件的旋回性薄互层进行正演模拟,分别抽取零偏移距道集进行仿射类时频分析,对比理想情况的旋回性薄互层时频特征差异。结果表明:仿射类时频分布判别沉积旋回抗噪能力强,受薄互层中小层厚度轻微突变的影响小;波阻抗的变化主要影响时频谱时间方向能量分布,对频率方向能量分布影响甚微;地震资料主频变化对时频特征的影响较小,随着地震资料主频的增加,旋回的趋势更加明显;地层黏性吸收作用对该方法判别的准确度影响也较小,时频特征稳定。 展开更多
关键词 仿射类时频分析 薄互层 旋回性 正演模拟 黏性吸收
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Dual-stage Optimal Iterative Learning Control for Nonlinear Non-affine Discrete-time Systems 被引量:20
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作者 CHI Rong-Hu HOU Zhong-Sheng 《自动化学报》 EI CSCD 北大核心 2007年第10期1061-1065,共5页
根据沿着重复轴的一种新动态 linearization 技术,双阶段的最佳的反复的学习控制为非线性、非仿射的分离时间的系统被介绍。双阶段显示二个最佳的学习阶段分别地被设计反复地改进控制输入顺序和学习获得。主要特征是控制器设计和集中... 根据沿着重复轴的一种新动态 linearization 技术,双阶段的最佳的反复的学习控制为非线性、非仿射的分离时间的系统被介绍。双阶段显示二个最佳的学习阶段分别地被设计反复地改进控制输入顺序和学习获得。主要特征是控制器设计和集中分析仅仅取决于动态系统的 I/O 数据。换句话说,没有知道系统的任何另外的知识,我们能容易选择控制参数。模拟学习沿着重复轴说明介绍方法的几何集中,在哪个马路的一个例子控制为它的内在的工程重要性是引人注目的交通反复的学习。 展开更多
关键词 非线性系统 离散时间系统 自适应控制 迭代学习控制 匝道交通调节
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Forward Affine Point Set Matching Under Variational Bayesian Framework 被引量:1
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作者 QU Han-Bing CHEN Xi +1 位作者 WANG Song-Tao YU Ming 《自动化学报》 EI CSCD 北大核心 2015年第8期1482-1494,共13页
关键词 贝叶斯 点集 匹配 仿射 框架 变分 逼近算法 线性变换
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Output Feedback Control of Discrete-Time T-S Fuzzy Affine Systems Using Quantized Measurements
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作者 Wenqiang Ji Jianbin Qiu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第3期43-54,共12页
This paper investigates the problem of robust H!fixed-order dynamic output feedback( DOF)controller design for a class of Takagi-Sugeno( T-S) fuzzy affine systems using quantized measurements.Through a state-input aug... This paper investigates the problem of robust H!fixed-order dynamic output feedback( DOF)controller design for a class of Takagi-Sugeno( T-S) fuzzy affine systems using quantized measurements.Through a state-input augmentation method,some sufficient conditions for controller synthesis are developed based upon piecewise quadratic Lyapunov functions( PQLFs) in terms of LMIs. Two illustrative studies are conducted to verify the effectiveness of the proposed controller synthesis approach. 展开更多
关键词 fuzzy affine models ROBUSTNESS dynamic output feedback measurement quantization
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Solving Major Problems Using Vector Affine Quantization
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期178-183,共6页
Affine quantization is a parallel procedure to canonical quantization, which is ideally suited to deal with special problems. Vector affine quantization introduces multiple degrees of freedom which find that working t... Affine quantization is a parallel procedure to canonical quantization, which is ideally suited to deal with special problems. Vector affine quantization introduces multiple degrees of freedom which find that working together creates novel tools suitable to eliminate typical difficulties encountered in more conventional approaches. 展开更多
关键词 affine QUANTIZATION Vector Field models Canonical Quantization
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Vector Affine Quantization Can Create Valid Quantum Field Theories
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期237-242,共6页
Affine quantization, a parallel procedure to canonical quantization, needs to use its principal quantum operators, specifically <i>D</i> = (<i>PQ</i>+<i>QP</i>)/2 and <i>Q<... Affine quantization, a parallel procedure to canonical quantization, needs to use its principal quantum operators, specifically <i>D</i> = (<i>PQ</i>+<i>QP</i>)/2 and <i>Q</i> ≠ 0, to represent appropriate kinetic factors, such as <i>P</i><sup>2</sup>, which involves only one canonical quantum operator. The need for this requirement stems from path integral quantizations of selected problems that affine quantization can solve but canonical quantization fails to solve. This task is resolved for simple examples, as well as examples that involve scalar, and vector, quantum field theories. 展开更多
关键词 affine Quantization Vector Field models Flexibility of the Dilation Variable
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Adsorption and Step Elution of Urokinase Using Affinity Chromatography-Comparison of Data with Rate Model Simulation
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作者 Mohammad Reza Aboudzadeh Rovais 《Chinese Journal of Biomedical Engineering(English Edition)》 2004年第4期166-178,共13页
A non-equilibrium chromatographic rate model was employed to simulate the affinity chromatography of urokinase. The chromatography process was developed to a yield of high purity product of urokinase from crude materi... A non-equilibrium chromatographic rate model was employed to simulate the affinity chromatography of urokinase. The chromatography process was developed to a yield of high purity product of urokinase from crude materials. The affinity gel used in the process was prepared by an epichlorohydrin-activation method using epichlorohydrin activated Sepharose 4B as a matrix and p-aminobenzamidine as a ligand. The chromatographic process were numerically simulated and analyzed with the aid of VERSE-LC computer simulator. Considering the basic principles, rate model with the back mixing in column inlet was utilized in simulating and studying the effect of the column inlet pattern on other parameters. Comparison of the simulation results with the experimental data showed that the rate model can be used to describe the affinity chromatography of urokinase in a fixed bed column with satisfactory accuracy. 展开更多
关键词 Rate model simulation affinity chromatography UROKINASE Back mixing
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基于区间理论的油田综合能源系统优化规划
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作者 王艳松 罗双禹 +2 位作者 苗人杰 倪承波 衣京波 《电力自动化设备》 EI CSCD 北大核心 2024年第3期31-39,共9页
针对油田的能源结构和用能负荷的特征,构建了油田综合能源系统架构;考虑可再生能源出力的不确定性和油田多元负荷用能的随机性,建立了光伏、光热出力的区间模型,热负荷区间模型和基于价格型响应的电负荷区间模型;通过分析设备投资成本... 针对油田的能源结构和用能负荷的特征,构建了油田综合能源系统架构;考虑可再生能源出力的不确定性和油田多元负荷用能的随机性,建立了光伏、光热出力的区间模型,热负荷区间模型和基于价格型响应的电负荷区间模型;通过分析设备投资成本的时间价值和区域碳中和途径,建立一种计及源荷不确定性的综合能源系统规划模型,并结合仿射算法和区间序关系,将不确定性优化问题转化为确定性的多目标优化问题进行求解。算例分析表明,油田综合能源系统架构符合油田能源禀赋和负荷实际耦合情况,设备配置方案投资回收年限短,不确定性权重系数越高,投资越大,年净收益区间越大,结果验证了规划方法的有效性。与传统鲁棒凸规划优化方法相比,所提方法为决策者提供了满足区间约束的解集,避免了规划方案的保守性。 展开更多
关键词 综合能源系统 仿射算法 不确定性 优化规划 多目标区间优化模型
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基于中心对称特征耦合仿射度量模型的图像匹配方法
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作者 李俊 《机械与电子》 2024年第9期18-24,共7页
针对当下较多图像匹配算法利用距离度量法来实现特征匹配,没考虑图像仿射变换的影响,使得匹配结果准确率不高的问题,提出了中心对称特征耦合仿射度量模型的图像匹配算法。首先,引入Forstner算子,利用像素点的GS梯度特征提取特征点;然后... 针对当下较多图像匹配算法利用距离度量法来实现特征匹配,没考虑图像仿射变换的影响,使得匹配结果准确率不高的问题,提出了中心对称特征耦合仿射度量模型的图像匹配算法。首先,引入Forstner算子,利用像素点的GS梯度特征提取特征点;然后,利用图像的Haar小波信息与中心对称像素点的灰度值,求取特征向量;接着,利用特征点之间的旋转、平移以及缩放的仿射特征,构造仿射度量模型,利用其计算出匹配的特征点对;最后,采用结构相似度(SSIM)函数,计算匹配点对的结构相似性,对匹配点对去伪求真,以求取最优匹配效果。实验结果表明,与当下匹配方法相比,所提算法不仅能更准确地实现图像匹配,而且还能够更好地适应具有仿射变换关系图像之间的匹配。 展开更多
关键词 图像匹配 中心对称特征 仿射度量模型 结构相似度函数 FORSTNER算子
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基于简化HMM和时间分段的非侵入式负荷分解算法
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作者 刘凯 符玲 +3 位作者 杨金刚 熊思宇 蒿保龙 刘丽娜 《电力自动化设备》 EI CSCD 北大核心 2024年第2期198-203,210,共7页
针对现有非侵入式负荷分解算法需要以过去时刻的分解结果为依据,从而造成误差累积的问题,提出一种基于简化的隐马尔可夫模型和时间分段的非侵入式负荷分解算法,以实现居民家庭的负荷分解。对负荷的低频功率信号进行分层抽样和聚类分析,... 针对现有非侵入式负荷分解算法需要以过去时刻的分解结果为依据,从而造成误差累积的问题,提出一种基于简化的隐马尔可夫模型和时间分段的非侵入式负荷分解算法,以实现居民家庭的负荷分解。对负荷的低频功率信号进行分层抽样和聚类分析,构建负荷功率模板并利用独热码对超状态进行编码表示。基于简化的隐马尔可夫模型和普遍生活规律对家庭用电时间段进行划分,在每个时间段内单独训练参数。结合总线数据和各时间段参数实现对各时刻负荷功率的独立求解。基于2种国外公开数据集的测试结果验证了所提算法的准确性和实时性。 展开更多
关键词 负荷分解 隐马尔可夫模型 亲和力传播聚类 时间分段 超状态
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基于分段仿射阻抗模型的电压源变流器小扰动稳定域在线构造
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作者 马悦鑫 王鹏 +3 位作者 赵浩然 贺敬 罗嘉 王金龙 《中国电机工程学报》 EI CSCD 北大核心 2024年第14期5667-5679,I0019,共14页
近年来小扰动振荡事故频发,亟需建立能反映新能源并网系统全工况的在线稳定域。小扰动在线稳定域可以为时变性和波动性下新型电力系统的安全评估和控制优化提供强有力的支撑。因此,提出基于分段仿射阻抗模型的电压源变流器(voltage sour... 近年来小扰动振荡事故频发,亟需建立能反映新能源并网系统全工况的在线稳定域。小扰动在线稳定域可以为时变性和波动性下新型电力系统的安全评估和控制优化提供强有力的支撑。因此,提出基于分段仿射阻抗模型的电压源变流器(voltage source converter,VSC)小扰动稳定域在线构造方法。首先,该方法使用电压、功率和频域因子作为分区变量,离线构建VSC的分段仿射阻抗模型。在线计算时根据运行工况可以快速定位运行分区并确定对应的线性仿射模型,从而极大地提高阻抗计算的效率。其次,提出VSC稳定域边界点的双层优化模型,利用改进的广义奈奎斯特判据和复合形法进行快速求解。然后,通过改变双层优化模型的求解方向搜索边界点,基于分段拟合获取准确的边界解析式。最后,仿真算例和实验结果表明,分段仿射阻抗模型与全阶阻抗模型误差小于1%;该方法可以准确和高效地构建在线稳定域。 展开更多
关键词 小扰动建模 阻抗法 分段仿射 稳定域 复合形法
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增强获得感 提升亲和力——思政课“专题+体验”德育模式的探索与实践 被引量:2
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作者 周霞 陆怡楠 谢钦灵 《高教学刊》 2024年第5期164-168,共5页
增强获得感,提升亲和力,是完成思政课教学目标的需要,是应对信息化给思政课带来严峻挑战的需要,是适应“00后”大学生成长特点的需要,也是消除传统教学模式弊端和提高思政课实效的需要。在各种教学模式中,“专题+体验”德育模式能扬长... 增强获得感,提升亲和力,是完成思政课教学目标的需要,是应对信息化给思政课带来严峻挑战的需要,是适应“00后”大学生成长特点的需要,也是消除传统教学模式弊端和提高思政课实效的需要。在各种教学模式中,“专题+体验”德育模式能扬长避短、优势互补。具体实施途径包括,在专题教学中渗透体验、在体验式教学中凸显专题等。 展开更多
关键词 获得感 亲和力 专题德育模式 主体性 德育
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分段仿射模型在智能车辆混合控制的应用研究
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作者 黄智 王月雷 何金戈 《机械设计与制造》 北大核心 2024年第7期31-39,共9页
针对智能车辆混合动力学控制问题,首先采用分段仿射模型(PWA)非线性逼近车辆主要部件的系统特性,将智能车辆纵向动力学转化为计算混合逻辑动力学(MLD)模型,在此基础上提出了混合模型预测控制(HMPC)策略。通过求解混合整数二次规划(MIQP... 针对智能车辆混合动力学控制问题,首先采用分段仿射模型(PWA)非线性逼近车辆主要部件的系统特性,将智能车辆纵向动力学转化为计算混合逻辑动力学(MLD)模型,在此基础上提出了混合模型预测控制(HMPC)策略。通过求解混合整数二次规划(MIQP)问题,设计了能够计算智能车辆纵向工作模式(二进制控制输入),以及节气门开口度和制动压力(连续控制输入)在自动调速过程中切换顺序的控制器。最后通过仿真对比模拟分析,验证了所设计的混合控制器在典型工况下具有良好的纵向速度调节控制性能。 展开更多
关键词 智能车辆 分段仿射系统 混合逻辑动力学模型 速度控制
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基于模型预测控制的多能源微网仿射优化调度
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作者 陈飞雄 郭奕鑫 +3 位作者 邵振国 蔡明杰 林炜晖 李壹民 《电力自动化设备》 EI CSCD 北大核心 2024年第9期24-31,48,共9页
受源荷日前预测误差较大的影响,多能源微网存在优化调度方案变化范围较大,且难有足够的不确定性应对裕度的问题。为解决上述问题,提出一种基于模型预测控制的多能源微网仿射优化调度方法。首先,通过不断更新预测信息以保证源荷预测精度... 受源荷日前预测误差较大的影响,多能源微网存在优化调度方案变化范围较大,且难有足够的不确定性应对裕度的问题。为解决上述问题,提出一种基于模型预测控制的多能源微网仿射优化调度方法。首先,通过不断更新预测信息以保证源荷预测精度。在此基础上,采用仿射算法表征源荷预测的不确定性。然后,将仿射优化调度模型嵌入滚动优化中,并在每次滚动优化中求解仿射优化调度模型。最后,仿真结果验证了所提方法能够有效降低优化调度方案的保守性与提高不确定性应对能力。 展开更多
关键词 多能源微网 源荷不确定性 仿射算法 模型预测控制 日内调度
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Gluing Affine Vortices
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作者 Guang Bo XU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第1期250-312,共63页
We provide an analytical construction of the gluing map for stable affine vortices over the upper half plane with the Lagrangian boundary condition.This result is a necessary ingredient in studies of the relation betw... We provide an analytical construction of the gluing map for stable affine vortices over the upper half plane with the Lagrangian boundary condition.This result is a necessary ingredient in studies of the relation between gauged sigma model and nonlinear sigma model,such as the closed or open quantum Kirwan map. 展开更多
关键词 affine vortices gauged linear sigma model adiabatic limit symplectic reduction
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