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Searching for an Optimized Single-objective Function Matching Multiple Objectives with Automatic Calibration of Hydrological Models
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作者 TIAN Fuqiang HU Hongchang +2 位作者 SUN Yu LI Hongyi LU Hui 《Chinese Geographical Science》 SCIE CSCD 2019年第6期934-948,共15页
In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies,... In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies, there is a general opinion that no single-objective function can represent all important characteristics of even one specific hydrological variable(e.g., streamflow).Thus hydrologists must turn to multi-objective calibration.In this study, we demonstrated that an optimized single-objective function can compromise multi-response modes(i.e., multi-objective functions) of the hydrograph, which is defined as summation of a power function of the absolute error between observed and simulated streamflow with the exponent of power function optimized for specific watersheds.The new objective function was applied to 196 model parameter estimation experiment(MOPEX) watersheds across the eastern United States using the semi-distributed Xinanjiang hydrological model.The optimized exponent value for each watershed was obtained by targeting four popular objective functions focusing on peak flows, low flows, water balance, and flashiness, respectively.Results showed that the optimized single-objective function can achieve a better hydrograph simulation compared to the traditional single-objective function Nash-Sutcliffe efficiency coefficient for most watersheds, and balance high flow part and low flow part of the hydrograph without substantial differences compared to multi-objective calibration.The proposed optimal single-objective function can be practically adopted in the hydrological modeling if the optimal exponent value could be determined a priori according to hydrological/climatic/landscape characteristics in a specific watershed. 展开更多
关键词 automatic calibration single-objective function MULTI-objective functions Xinanjiang model HYDROLOGICAL model
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A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model 被引量:1
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作者 Yinhan Gao Jun Xie +2 位作者 Jie Liang Xin Chang Baojun Wu 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第2期199-208,共10页
Based on auditory peripheral simulation model,a new Sound Quality Objective Evaluation(SQOE)method is presented,which can be used to model and analyze the impacts of head,shoulder and other parts of human body on soun... Based on auditory peripheral simulation model,a new Sound Quality Objective Evaluation(SQOE)method is presented,which can be used to model and analyze the impacts of head,shoulder and other parts of human body on sound wave trans-mission.This method employs the artificial head technique,in which the head related transfer function was taken into account tothe outer ear simulation phase.First,a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical explanations.Then the auditory peripheral simulation model was built,which mimicsthe physiological functions of the human hearing,simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory system.Finally,performance comparison was made between the proposed SQOEmethod and ArtemiS software,and the verifications of subjective and objective related analysis were made.Results show thatthe proposed method was economical,simple,and with good evaluation quality. 展开更多
关键词 sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function
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Performance Monitoring of the Data-driven Subspace Predictive Control Systems Based on Historical Objective Function Benchmark 被引量:3
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作者 王陆 李柠 李少远 《自动化学报》 EI CSCD 北大核心 2013年第5期542-547,共6页
关键词 预测控制系统 性能监控 数据驱动 子空间 历史 基准 监视控制器 目标函数
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A Distributed Strategy for Defensing Objective Function Attack in Large-scale Cognitive Networks
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作者 Guangsheng Feng Junyu Lin +3 位作者 Huiqiang Wang Xiaoyu Zhao Hongwu Lv Qiao Zhao 《国际计算机前沿大会会议论文集》 2015年第1期4-5,共2页
Most of existed strategies for defending OFA (Objective Function Attack)are centralized, only suitable for small-scale networks and stressed on the computation complexity and traffic load are usually neglected. In thi... Most of existed strategies for defending OFA (Objective Function Attack)are centralized, only suitable for small-scale networks and stressed on the computation complexity and traffic load are usually neglected. In this paper, we pay more attentions on the OFA problem in large-scale cognitive networks, where the big data generated from the network must be considered and the traditional methods could be of helplessness. In this paper, we first analyze the interactive processes between attacker and defender in detail, and then a defense strategy for OFA based on differential game is proposed, abbreviated as DSDG. Secondly, the game saddle point and optimal defense strategy have proved to be existed simultaneously. Simulation results show that the proposed DSDG has a less influence on network performance and a lower rate of packet loss.More importantly, it can cope with the large range 展开更多
关键词 COGNITIVE NETWORKS objective function ATTACK GAME model
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Object-Oriented Modeling of the Variation of Acceleration and Deceleration Characteristics in Relation to Speed Bands for Railway Vehicles
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作者 Hyun-Soo Jeong Jong-Young Park Hanmin Lee 《Energy and Power Engineering》 2023年第8期277-290,共14页
Automated operation and artificial intelligence technology have become essential for ensuring the safety, efficiency, and punctuality of railways, with applications such as ATO (Automatic Train Operation). In this stu... Automated operation and artificial intelligence technology have become essential for ensuring the safety, efficiency, and punctuality of railways, with applications such as ATO (Automatic Train Operation). In this study, the authors propose a method to efficiently simulate the kinematic characteristics of railroad vehicles depending on their speed zone. They utilized the function overloading function supported by a programming language and applied the fourth-order Lunge-Kutta method for dynamic simulation. By constructing an object model, the authors calculated vehicle characteristics and TPS and compared them with actual values, verifying that the developed model represents the real-life vehicle characteristics accurately. The study highlights potential improvements in automated driving and energy consumption optimization in the railway industry. 展开更多
关键词 Railway Vehicle ATO Lunge-Kutta Method object-Oriented model function Overloading
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基于独立成分分析法的光纤通信网络频谱分配研究
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作者 杨华 胡珺 邱祥阳 《激光杂志》 北大核心 2026年第1期200-207,共8页
为了提高光纤通信网络频谱分配质量,提出了基于独立成分分析法的光纤通信网络频谱分配方法。通过自适应步长独立成分分析法对光纤通信网络信道均衡处理,即以两个光纤通信网络源信号间的统计独立性作为判断标准来构建信道频响分离矩阵,... 为了提高光纤通信网络频谱分配质量,提出了基于独立成分分析法的光纤通信网络频谱分配方法。通过自适应步长独立成分分析法对光纤通信网络信道均衡处理,即以两个光纤通信网络源信号间的统计独立性作为判断标准来构建信道频响分离矩阵,信道频响分离矩阵对于原始信号中的干扰成分进行补偿,以信道均衡处理后的光纤通信网络为基础,确定最大化频谱利用率、最小化干扰、最大化公平性等目标函数,以此搭建光纤通信网络频谱分配模型,利用蛙跳算法对于该模型进行求解,所得最优解即为最优的光纤通信网络频谱分配方案。实验结果表明,所提方法的丢包率最大值为4.12%,频谱利用率为24.12%,带宽阻塞率为18.87%,光纤通信网络频谱分配效果好。 展开更多
关键词 独立成分分析法 光纤通信网络 频谱分配 目标函数 分配模型 蛙跳算法
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组合代理模型中冠状动脉支架的多目标优化设计
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作者 张珂 王培瑶 +2 位作者 王博涵 朱雨婷 王川 《中国组织工程研究》 北大核心 2026年第26期6752-6759,共8页
背景:经皮冠状动脉介入支架植入主要应用于冠状动脉狭窄的治疗,但当前支架多目标优化方法受限于样本容量约束,在平衡支撑性与柔顺性等关键性能指标时存在预测精度不足的瓶颈,制约了支架优化设计的有效性。目的:提出一种基于组合代理模... 背景:经皮冠状动脉介入支架植入主要应用于冠状动脉狭窄的治疗,但当前支架多目标优化方法受限于样本容量约束,在平衡支撑性与柔顺性等关键性能指标时存在预测精度不足的瓶颈,制约了支架优化设计的有效性。目的:提出一种基于组合代理模型的冠状动脉支架多目标优化设计方法。方法:构建血管支架三维参数化模型,通过有限元仿真建立力学响应数据库。采用动态权重融合策略,整合Kriging模型全局优化特性与径向基函数模型代理模型局部非线性表征优势,基于20组初始样本构建组合代理模型,应用非支配排序遗传算法Ⅱ进行参数空间寻优。结果与结论:实验结果表明,组合代理模型在有限样本下展现出显著优势,支架的径向刚度倒数预测决定系数达0.9742,较单一模型组提升4.4%的精度,验证了组合代理模型在有限样本下的高效建模能力;支架的弯曲刚度预测精度较单一径向基函数模型代理模型组提升4.4%。优化后支架性能实现双目标协同优化,组合代理模型组支架的径向刚度倒数较Kriging模型组和单一径向基函数模型代理模型组分别降低13.92%和9.57%,支架的弯曲刚度较Kriging模型组和单一径向基函数模型代理模型组分别优化了0.38%和2.56%。研究提出的组合代理模型突破了传统单一模型的性能局限,为冠状动脉支架的“刚性-柔性”协同优化提供了低成本、高精度的解决方案。 展开更多
关键词 冠状动脉支架 组合代理模型 多目标优化 有限元分析 生物力学 优化方法 径向刚度 弯曲刚度 KRIGING模型 径向基函数
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基于自适应定频模型预测的直流微电网振荡抑制策略
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作者 王宗旭 易伟 +3 位作者 付欤翔 邓攀 张庸 陈亮 《四川电力技术》 2026年第1期53-60,共8页
针对直流微电网的失稳问题,提出了一种抑制直流微电网振荡的自适应定频模型预测控制方法。首先,提出了一种零电压矢量注入的定频处理方法,运用空间矢量脉宽调制得到相应的开关管状态;其次,在传统模型预测控制的基础上加入直流侧控制目标... 针对直流微电网的失稳问题,提出了一种抑制直流微电网振荡的自适应定频模型预测控制方法。首先,提出了一种零电压矢量注入的定频处理方法,运用空间矢量脉宽调制得到相应的开关管状态;其次,在传统模型预测控制的基础上加入直流侧控制目标;然后,设计了自适应目标函数,并对目标函数进行评估得到最优电压矢量。所提方法解决了传统模型预测控制权重因子选取困难和开关频率不固定的问题,同时自适应目标函数可以根据直流侧误差和交流侧误差来调整各控制目标之间的权重,从而使系统具有动态自适应能力。最后,采用Matlab/Simulink对自适应定频模型预测控制系统进行仿真,验证了所提方法的有效性。 展开更多
关键词 直流微电网稳定性 模型预测控制 定频 空间矢量脉宽调制 自适应目标函数
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考虑AI大模型的多维网络安全度量及主动防御策略
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作者 徐胜超 蒋大锐 吕峻闽 《计算机技术与发展》 2026年第3期215-220,F0003,共7页
利用单一维度表征网络安全状态的参量进行度量时,参量的畸变会引起度量误差,导致生成的防御策略难以保障攻击场景下网络的安全。为此,论文引入AI大模型对多维网络安全进行度量,并生成主动防御策略。从主机状态和网络状态两个角度出发,在... 利用单一维度表征网络安全状态的参量进行度量时,参量的畸变会引起度量误差,导致生成的防御策略难以保障攻击场景下网络的安全。为此,论文引入AI大模型对多维网络安全进行度量,并生成主动防御策略。从主机状态和网络状态两个角度出发,在7个维度上对表征网络安全状态的参量进行量化,并拟合权重输出网络安全度量结果,避免了单一维度参量畸变引起的度量误差。利用整数线性规划的方式对网络切片进行部署时,将安全度量值最大值化作为目标函数,在AI大模型下更新网络切片迁移结果,直至目标函数达到收敛,输出主动防御策略。仿真结果中,设计技术在实现对网络安全状态准确度量的基础上,生成的主动防御策略能够有效降低攻击的成功率,攻击类型为数据泄露时,该方法的主动防御策略生成耗时仅为21 ms,节点数量为30个时,该方法的攻击成功率为2.3%,表明该方法防御策略效果好。 展开更多
关键词 AI大模型 多维网络安全度量 主动防御策略 整数线性规划 目标函数 网络切片迁移
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Dynamic finite element model updating of prestressed concrete continuous box-girder bridge 被引量:6
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作者 Lin Xiankun Zhang Lingmi +1 位作者 Guo Qintao Zhang Yufeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第3期399-407,共9页
The dynamic finite element model (FEM) of a prestressed concrete continuous box-girder bridge, called the Tongyang Canal Bridge, is built and updated based on the results of ambient vibration testing (AVT) using a... The dynamic finite element model (FEM) of a prestressed concrete continuous box-girder bridge, called the Tongyang Canal Bridge, is built and updated based on the results of ambient vibration testing (AVT) using a real-coded accelerating genetic algorithm (RAGA). The objective functions are defined based on natural frequency and modal assurance criterion (MAC) metrics to evaluate the updated FEM. Two objective functions are defined to fully account for the relative errors and standard deviations of the natural frequencies and MAC between the AVT results and the updated FEM predictions. The dynamically updated FEM of the bridge can better represent its structural dynamics and serve as a baseline in long-term health monitoring, condition assessment and damage identification over the service life of the bridge . 展开更多
关键词 prestressed concrete continuous box-girder bridge field ambient vibration testing dynamic characteristics model updating accelerating genetic algorithm objective function
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Hierarchical model updating strategy of complex assembled structures with uncorrelated dynamic modes 被引量:4
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作者 Chengwei FEI Haotian LIU +2 位作者 Rhea PATRICIA LIEM Yatsze CHOY Lei HAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第3期281-296,共16页
In structural simulation and design,an accurate computational model directly determines the effectiveness of performance evaluation.To establish a high-fidelity dynamic model of a complex assembled structure,a Hierarc... In structural simulation and design,an accurate computational model directly determines the effectiveness of performance evaluation.To establish a high-fidelity dynamic model of a complex assembled structure,a Hierarchical Model Updating Strategy(HMUS)is developed for Finite Element(FE)model updating with regard to uncorrelated modes.The principle of HMUS is first elaborated by integrating hierarchical modeling concept,model updating technology with proper uncorrelated mode treatment,and parametric modeling.In the developed strategy,the correct correlated mode pairs amongst the uncorrelated modes are identified by an error minimization procedure.The proposed updating technique is validated by the dynamic FE model updating of a simple fixed–fixed beam.The proposed HMUS is then applied to the FE model updating of an aeroengine stator system(casings)to demonstrate its effectiveness.Our studies reveal that(A)parametric modeling technique is able to build an efficient equivalent model by simplifying complex structure in geometry while ensuring the consistency of mechanical characteristics;(B)the developed model updating technique efficiently processes the uncorrelated modes and precisely identifies correct Correlated Mode Pairs(CMPs)between FE model and experiment;(C)the proposed HMUS is accurate and efficient in the FE model updating of complex assembled structures such as aeroengine casings with large-scale model,complex geometry,high-nonlinearity and numerous parameters;(D)it is appropriate to update a complex structural FE model parameterized.The efforts of this study provide an efficient updating strategy for the dynamic model updating of complex assembled structures with experimental test data,which is promising to promote the precision and feasibility of simulation-based design optimization and performance evaluation of complex structures. 展开更多
关键词 Aeroengine casings Assembled structures Correlated mode pair Hierarchical model updating objective function Uncorrelated modes
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On the Consortium for Business Object Promotion (CBOP)
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作者 Hajime Horiuchi Management Information,Tokyo International University, 1 13 1 Matobakita, kawagoe, Saitama 350\|1197, Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期25-30,共6页
This paper deals with the goals and visions of a consortium in Japan, named Consortium for Business Object Promotion (CBOP), discussing its background, activities, and basic technical approaches to share and exchangin... This paper deals with the goals and visions of a consortium in Japan, named Consortium for Business Object Promotion (CBOP), discussing its background, activities, and basic technical approaches to share and exchanging various types of Business Objects. Especially, Object Pattern Technologies used in CBOP should be discussed. 展开更多
关键词 business object object pattern software framework software component business function object pattern (BFOP) object registry meta model framework
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Method for Visual Localization of Oil and Gas Wellhead Based on Distance Function of Projected Features
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作者 Ying Xie Xiang-Dong Yang +2 位作者 Zhi Liu Shu-Nan Ren Ken Chen 《International Journal of Automation and computing》 EI CSCD 2017年第2期147-158,共12页
A localization method based on distance function of projected features is presented to solve the accuracy reduction or failure problem due to occlusion and blurring caused by smog, when dealing with vision based local... A localization method based on distance function of projected features is presented to solve the accuracy reduction or failure problem due to occlusion and blurring caused by smog, when dealing with vision based localization for target oil and gas wellhead (OGWH). Firstly, the target OGWH is modeled as a cylinder with marker, and a vector with redundant parameter is used to describe its pose. Secondly, the explicit mapping relationship between the pose vector with redundant parameter and projected features is derived. Then, a 2D-point-to-feature distance function is proposed, as well as its derivative. Finally, based on this distance function and its derivative, an algorithm is proposed to estimate the pose of target OGWH directly according to the 2D image information, and the validity of the method is verified by both synthetic data and real image experiments. The results show that this method is able to accomplish the localization in the case of occlusion and blurring, and its anti-noise ability is good especially with noise ratio of less than 70%. 展开更多
关键词 Robot vision visual localization 3D object localization model based pose estimation distance function of projectedfeatures nonlinear least squares random sample consensus (RANSAC).
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Enhanced history matching process by incorporation of saturation logs as model selection criteria
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作者 APONTE Jesus Manuel WEBBER Robert +3 位作者 CENTENO Maria Astrid DHAKAL Hom Nath SAYED Mohamed Hassan MALAKOOTI Reza 《Petroleum Exploration and Development》 SCIE 2023年第2期450-463,共14页
This paper proposes a methodology for an alternative history matching process enhanced by the incorporation of a simplified binary interpretation of reservoir saturation logs(RST) as objective function. Incorporating ... This paper proposes a methodology for an alternative history matching process enhanced by the incorporation of a simplified binary interpretation of reservoir saturation logs(RST) as objective function. Incorporating fluids saturation logs during the history matching phase unlocks the possibility to adjust or select models that better represent the near wellbore waterfront movement, which is particularly important for uncertainty mitigation during future well interference assessments in water driven reservoirs. For the purposes of this study, a semi-synthetic open-source reservoir model was used as base case to evaluate the proposed methodology. The reservoir model represents a water driven, highly heterogenous sandstone reservoir from Namorado field in Brazil. To effectively compare the proposed methodology against the conventional methods, a commercial reservoir simulator was used in combination with a state-of-the-art benchmarking workflow based on the Big LoopTMapproach. A well-known group of binary metrics were evaluated to be used as the objective function, and the Matthew correlation coefficient(MCC) has been proved to offer the best results when using binary data from water saturation logs. History matching results obtained with the proposed methodology allowed the selection of a more reliable group of reservoir models,especially for cases with high heterogeneity. The methodology also offers additional information and understanding of sweep behaviour behind the well casing at specific production zones, thus revealing full model potential to define new wells and reservoir development opportunities. 展开更多
关键词 geological modeling reservoir model objective function binary classification history matching saturation logs
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Theoretical Study on Stochastic Modeling of Combined Gravity-Magnetic-Electric-Seismic Inversion and Its Application
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作者 YanHanjie YanHong +1 位作者 LiYunping ZhangXiaofeng 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期227-233,共7页
As gravity field, magnetic field, electric field and seismic wave field are all physical fields, their object function, reverse function and compound function are certainly infinite continuously differentiable functio... As gravity field, magnetic field, electric field and seismic wave field are all physical fields, their object function, reverse function and compound function are certainly infinite continuously differentiable functions which can be expanded into Taylor (Fourier) series within domain of definition and be further reduced into solving stochastic distribution function of series and statistic inference of optimal approximation. This is the basis of combined gravity-magnetic-electric-seismic inversion of stochastic modeling. It is an uncertainty modeling technology of combining gravity-magnetic-electric-seismic inversion built on the basis of separation of field and source gravity-magnetic difference-value (D-value) trend surface, taking distribution-independent fault system as its unit, depths of seismic and electric interfaces of interests as its corresponding bivariate compound reverse function of gravity-magnetic anomalies and using high order polynomial (high order trigonometric function) approximating to its series distribution. The difference from current dominant inversion techniques is that, first, it does not respectively create gravity-seismic, magnetic-seismic deterministic inversion model from theoretical model, but combines gravity-magnetic-electric-seismic stochastic inversion model from stochastic model; second, after the concept of equivalent geological body being introduced, using feature of independent variable of gravity-magnetic field functions, taking density and susceptibility related to gravity-magnetic function as default parameters of model, the deterministic model is established owing to better solution to the contradiction of difficulty in identifying strata and less test analytical data for density and susceptibility in newly explored area; third, under assumption of independent parent distribution, a real modeling by strata, the problem of difficult plane closure arising in profile modeling is avoided. This technology has richer and more detailed fault and strata information than sparse pattern seismic data in newly explored area, successfully inverses and plots structural map of Indosinian discontinuity in Hefei basin with combined gravity-magnetic-electric-seismic inversion. With development of high precision gravity-magnetic and overall geophysical technology, it is certain for introducing new methods of stochastic modeling and computational intelligence and promoting the development of combined gravity-magnetic-electric-seismic inversion to open a new substantial path. 展开更多
关键词 gravity-magnetic compound reverse function stochastic geological model probability statistics gravity-magnetic d-value trend surface analysis.
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Similarities of Model Predictive Control and Constrained Direct Inverse
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作者 László Richárd Tóth Lajos Nagy Ferenc Szeifert 《Intelligent Control and Automation》 2012年第3期278-283,共6页
To reach an acceptable controller strategy and tuning it is important to state what is considered “good”. To do so one can set up a closed-loop specification or formulate an optimal control problem. It is an interes... To reach an acceptable controller strategy and tuning it is important to state what is considered “good”. To do so one can set up a closed-loop specification or formulate an optimal control problem. It is an interesting question, if the two can be equivalent or not. In this article two controller strategies, model predictive control (MPC) and constrained direct inversion (CDI) are compared in controlling the model of a pilot-scale water heater. Simulation experiments show that the two methods are similar, if the manipulator movements are not punished much in MPC, and they act practically the same when a filtered reference signal is applied. Even if the same model is used, it is still important to choose tuning parameters appropriately to achieve similar results in both strategies. CDI uses an analytic approach, while MPC uses numeric optimization, thus CDI is more computationally efficient, and can be used either as a standalone controller or to supplement numeric optimization. 展开更多
关键词 model PREDICTIVE CONTROL INVERSE CONTROL objective function CLOSED-LOOP Specification Heat Transfer
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Estimation and analysis of vegetation parameters for the water cloud model
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作者 Xiangdong Qin Zhiguo Pang Jingxuan Lu 《River》 2024年第4期399-407,共9页
The Water Cloud Model(WCM)plays a crucial role in active microwave soil moisture inversion applications.Empirical parameters are important factors affecting the accuracy of WCM simulation,but the current evaluation of... The Water Cloud Model(WCM)plays a crucial role in active microwave soil moisture inversion applications.Empirical parameters are important factors affecting the accuracy of WCM simulation,but the current evaluation of empirical parameters only considers the forward simulation process,and insufficient consideration is given to the model inversion problem.This study proposes a new estimation method for vegetation parameters in the WCM by combining the soil backscattering model and the objective function.The effectiveness of the method is then verified using measured data.Simultaneously,this study also analyzes the factors influencing the evaluation of vegetation parameters in the WCM,resulting in the following conclusions.First,blindly utilizing vegetation parameters recommended by previous model studies is not advisable.To ensure the accuracy of the simulation,it is necessary to adjust the vegetation parameters appropriately.Second,to ensure the ability of the WCM solving both forward and inverse problems,it is advisable to consider both soil backscatter and surface backscatter simulations in the construction of the cost function.Third,soil backscatter simulations have an impact on the solution of vegetation parameters,and more accurate soil scattering models provide a better representation of the modeled vegetation.This study presents a dependable method for resolving the vegetation parameters of the WCM,thereby offering a valuable reference for the application of the model in surface parameter inversion research. 展开更多
关键词 backscattering coefficient gradient descent algorithm objective function soil moisture water cloud model
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基于改进蚁群算法的无线传感网络路由优化方法 被引量:3
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作者 李忠 严莉 +1 位作者 倪建军 汤嘉立 《计算机与网络》 2025年第1期67-75,共9页
为了提高传统无线传感网络路由的性能,提出基于改进蚁群算法的无线传感网络路由优化方法,包括路由控制层、SDN信息收集层和数据转发层。借助参考节点和锚节点确定未知节点位置,并根据节点位置设计优化目标函数。通过改进蚁群算法中的转... 为了提高传统无线传感网络路由的性能,提出基于改进蚁群算法的无线传感网络路由优化方法,包括路由控制层、SDN信息收集层和数据转发层。借助参考节点和锚节点确定未知节点位置,并根据节点位置设计优化目标函数。通过改进蚁群算法中的转移概率和信息素浓度,求解目标函数,获得最佳的路由方案。实验结果表明,该方法在能量消耗、传输时延、死亡节点数量和网络吞吐量等方面均有明显改善,有效提高了无线传感网络路由的性能。 展开更多
关键词 改进蚁群算法 无线传感网络 路由优化 路由模型 目标函数
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基于不同目标函数的WRF-Hydro模型参数敏感性研究 被引量:1
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作者 谷黄河 石怀轩 +2 位作者 孙敏涛 丁震 顾苏烨 《中国农村水利水电》 北大核心 2025年第1期61-69,共9页
水文与气象预报相结合可以有效提高洪水预报的精度和延长预见期,陆气耦合模型已成为水文气象学者研究的重点。WRF-Hydro模型作为新一代分布式陆气耦合模型在多尺度洪水预报中具有广阔的应用前景,但由于各物理过程参数化方案复杂,模型计... 水文与气象预报相结合可以有效提高洪水预报的精度和延长预见期,陆气耦合模型已成为水文气象学者研究的重点。WRF-Hydro模型作为新一代分布式陆气耦合模型在多尺度洪水预报中具有广阔的应用前景,但由于各物理过程参数化方案复杂,模型计算量大,对该模型的参数敏感性研究还不充分,也影响着模型的模拟精度。研究以湿润区的新安江上游屯溪流域为研究对象,构建多个单目标和多目标函数,并结合Morris全局参数敏感性分析方法,探究了WRF-Hydro模型在不同目标函数下的参数敏感性。结果表明:土壤参数(DKSAT、SMCMAX、BEXP)主要影响壤中流和地表径流,对径流量影响显著,尤其DKSAT最为敏感,直接影响水在土壤中的下渗速度,增大时基流量显著增高而洪峰流量则明显降低;产流参数(SLOPE、REFKDT)主要影响地表径流和基流分配,对洪水过程线形状有重要影响;河道汇流参数ManN影响汇流速度并主要控制峰现时间;植被参数MP对于总水量有一定影响;坡面汇流参数OVROUGHRTFAC和地下水参数Zmax则最不敏感。不同目标函数下的参数敏感性顺序和最优参数取值有一定差异,单目标函数中以相对误差为优化目标会更侧重于全年径流总量和低流量部分的模拟精度,而以效率系数和Kling-Gupta系数为目标则更侧重于场次洪水和高流量部分的模拟效果;基于几个单目标函数组合的多目标函数综合考虑了不同目标函数的影响,结果在一定程度上优于单目标函数。研究可为合理确定WRF-Hydro模型参数优化策略提供参考。 展开更多
关键词 WRF-Hydro模型 Morris法 敏感性分析 多目标函数 洪水预报
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开关电感准Z源逆变器无权重系数FCS-MPC策略
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作者 刘春喜 林枝伟 +1 位作者 刘志乐 徐可 《电机与控制学报》 北大核心 2025年第3期142-154,共13页
针对开关电感准Z源逆变器采用有限集模型预测控制(FCS-MPC)时目标函数权重系数设计复杂的问题,提出一种无权重系数的FCS-MPC算法,避免了繁琐的权重系数调整过程。通过伏秒平衡原理分析电感周期性充放电的机理,在直通状态时对电感电流设... 针对开关电感准Z源逆变器采用有限集模型预测控制(FCS-MPC)时目标函数权重系数设计复杂的问题,提出一种无权重系数的FCS-MPC算法,避免了繁琐的权重系数调整过程。通过伏秒平衡原理分析电感周期性充放电的机理,在直通状态时对电感电流设置一个中间值,根据中间值和预测值的比较来确定下一周期的开关状态,在非直通状态时则采用归一化思想将输出电流和电容电压的目标函数设计为基于动态变化的函数,将误差限制在[0,1]范围内,从而不需要任何权重系数,避免了权重系数的调整过程,最后通过仿真和实验对所提的方法进行验证。结果表明:所提无权重系数FCS-MPC策略与传统FCS-MPC策略相比,在无权重系数的情况下,系统的稳态性能相同,动态性能更优。 展开更多
关键词 开关电感准Z源逆变器 有限集模型预测控制 无权重系数 目标函数 伏秒平衡 归一化
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