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Nonlinear Decoupling PID Control Using Neural Networks and Multiple Models 被引量:8
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作者 Lianfei ZHAI Tianyou CHAI 《控制理论与应用(英文版)》 EI 2006年第1期62-69,共8页
For a class of complex industrial processes with strong nonlinearity, serious coupling and uncertainty, a nonlinear decoupling proportional-integral-differential (PID) controller is proposed, which consists of a tra... For a class of complex industrial processes with strong nonlinearity, serious coupling and uncertainty, a nonlinear decoupling proportional-integral-differential (PID) controller is proposed, which consists of a traditional PID controller, a decoupling compensator and a feedforward compensator for the unmodeled dynamics. The parameters of such controller is selected based on the generalized minimum variance control law. The unmodeled dynamics is estimated and compensated by neural networks, a switching mechanism is introduced to improve tracking performance, then a nonlinear decoupling PID control algorithm is proposed. All signals in such switching system are globally bounded and the tracking error is convergent. Simulations show effectiveness of the algorithm. 展开更多
关键词 NONLINEAR decoupling control PID Neural networks Multiple models Generalized minimum variance
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A Decoupling Control Model on Perturbation Method for Twin-Roll Casting Magnesium Alloy Sheet 被引量:4
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作者 Wenyu Zhang Dongying Ju +3 位作者 Hongyang Zhao Xiaodong Hu Yao Yao Yujun Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第5期517-522,共6页
To better understand the twin-roll casting process,based on the analysis of the solidification phenomenon,the geometry shape of the molten metal pool,the continuity of metal and the balance of energy and momentum,five... To better understand the twin-roll casting process,based on the analysis of the solidification phenomenon,the geometry shape of the molten metal pool,the continuity of metal and the balance of energy and momentum,five critical partial equations were established separately including the equations of pool level,solidification process,roll separating force,roll gap and casting speed.Meanwhile,to obtain a uniform sheet thickness and keep a constant roll separating force,a decoupling control model was built on the perturbation method to eliminate the interference of process parameters.The simulation results show that the control model is valuable to quickly and accurately determine the control parameters.Moreover,Mg alloy sheets with high quality were cast by applying this model. 展开更多
关键词 Twin-roll casting decoupling control model Perturb
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Decoupling Conditions for Elasto-plastic Consolidation Question Based on Numerical Modeling Method 被引量:1
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作者 Cheng Tao Wang Jingtao Dong Bichang 《Journal of China University of Geosciences》 SCIE CSCD 2005年第4期363-368,共6页
Elasto-plastic consolidation is one of the classic coupling questions in geomechanics. To solve this problem, an elasto-plastic constitutive model is derived based on the numerical modeling method. The model is applie... Elasto-plastic consolidation is one of the classic coupling questions in geomechanics. To solve this problem, an elasto-plastic constitutive model is derived based on the numerical modeling method. The model is applied to Blot's consolidation theory. Incremental governing partial differential equations are established using this method. According to the stress path, the decoupling condition of these equations is discussed. Based on these conditions, an incremental diffusion equation and uncoupling governing equations are presented. The method is then applied to numerical analyses of three examples. The results show that (1) the effect of the stress path should be taken into account in the simulation of the soil consolidation question; (2) this decoupling method can predict the evolvement of pore water pressure; (3) the settlement using cam-clay model is less than that using numerical model because of dilatancy. 展开更多
关键词 numerical modeling method Blot's consolidation stress path constitutive model liquisolid coupling decouple incremental diffusion equation dilatancy.
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Modeling and Decoupling of Coupling Tasks in Collaborative Development Process of Complicated Electronic Products
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作者 WANG Xiaofei LIAO Wenhe +3 位作者 GUO Yu WANG Falin PAN Zhihao LIU Daoyuan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第5期868-878,共11页
It is important to improve the development efficiency of decoupling a coupling task package according to the information relevancy relation between development tasks in the collaborative development process of complic... It is important to improve the development efficiency of decoupling a coupling task package according to the information relevancy relation between development tasks in the collaborative development process of complicated electronic products.In order to define the task coupling model in the development process,the weighted directed graph based on the information relevancy is established,and the correspondence between weighted directed graph model and numerical design structure matrix model of coupling tasks is introduced.The task coupling model is quantized,thereby the interactivity matrix of task package is built.A multi-goal task decoupling method based on improved genetic algorithm is proposed to decouple the task coupling model,which transforms the decoupling of task package into a multi-goal optimization issue.Then the improved genetic algorithm is used to solve the interactivity matrix of coupling tasks.Finally,the effectiveness of this decomposition method is proved by using the example of task package decoupling of collaborative development of a radar’s phased array antenna. 展开更多
关键词 TASK COUPLING model TASK decoupling weighted directed graph design structure matrix GENETIC algorithm
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Multiple models adaptive feedforward decoupling controller
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作者 Wang Xin Li Shaoyuan Wang Zhongjie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期837-842,共6页
When the parameters of the system change abruptly, a new multivariable adaptive feedforward decoupling controller using multiple models is presented to improve the transient response. The system models are composed of... When the parameters of the system change abruptly, a new multivariable adaptive feedforward decoupling controller using multiple models is presented to improve the transient response. The system models are composed of multiple fixed models, one free-running adaptive model and one re-initialized adaptive model. The fixed models are used to provide initial control to the process. The re-initialized adaptive model can be reinitialized as the selected model to improve the adaptation speed. The free-running adaptive controller is added to guarantee the overall system stability. At each instant, the best system model is selected according to the switching index and the corresponding controller is designed. During the controller design, the interaction is viewed as the measurable disturbance and eliminated by the choice of the weighting polynomial matrix. It not only eliminates the steady-state error but also decouples the system dynamically. The gtobel convergence is obtained and several simulation examples are presented to illustrate the effectiveness of the proposed controller. 展开更多
关键词 multiple models FEEDFORWARD decoupling indirect adaptive control.
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Magnetic Properties of One-Dimensional Ferromagnetic Mixed-Spin Model within Tyablikov Decoupling Approximation
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作者 陈渊 项颖 宋闯闯 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期747-752,共6页
In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correla... In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correlationfunctions are obtained by using the Tyablikov decoupling approximation.Our results show that the magnetic susceptibilityand correlation length are a monotonically decreasing function of temperature regardless of the mixed spins.It isfound that in the case of S = s, our results of one-dimensional mixed-spin model is reduced to be those of the isotropicferromagnetic Heisenberg chain in the whole temperature region.Our results for the susceptibility are in agreement withthose obtained by other theoretical approaches. 展开更多
关键词 magnetic property Green's function method mixed-spin model Tyablikov decoupling approximation
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基于Decoupled-FR Net的伪造图像检测模型
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作者 杨桃 张乾 +1 位作者 文露露 彭杉 《湖北民族大学学报(自然科学版)》 2026年第1期69-74,共6页
针对伪造图像检测中细粒度特征感知与跨区域依赖建模的挑战,提出解耦频率细化网络(decoupled frequency refinement network, Decoupled-FR Net)检测模型。该模型设计了空间-通道解耦注意力机制,有效避免了传统混合注意力中的特征耦合问... 针对伪造图像检测中细粒度特征感知与跨区域依赖建模的挑战,提出解耦频率细化网络(decoupled frequency refinement network, Decoupled-FR Net)检测模型。该模型设计了空间-通道解耦注意力机制,有效避免了传统混合注意力中的特征耦合问题,提升了特征表示的独立性与判别力;引入了特征细化模块,通过层级特征校准与融合功能增强对细微篡改的感知能力;结合上下文感知机制,捕捉跨区域的长距离依赖关系,从而提升整体检测性能。结果表明,Decoupled-FR Net模型在伪造合成(forensic synthetics, ForenSynths)数据集上的准确率、平均精确率分别比块间依赖网络(inter-patch dependency network, IPD-Net)模型提高了2.4、0.5个百分点,在生成式对抗网络(generative adversarial network, GAN)的生成图像检测(GAN generation detection, GANGen-Detection)数据集上的平均精确率比频域网络(frequency domain network, FreqNet)模型提高了0.1个百分点。该模型为细粒度伪造图像检测提供了新的解决方案,在多媒体取证领域具有重要的应用价值。 展开更多
关键词 空间-通道注意力解耦 特征细化 频域增强 上下文感知 跨模型伪造图像检测 生成式对抗网络
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Decoupling economic growth from CO_2 emissions: A decomposition analysis of China's household energy consumption 被引量:4
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作者 MA Xiao-Wei YE Yi +1 位作者 SHI Xiu-Qing ZOU Le-Le 《Advances in Climate Change Research》 SCIE CSCD 2016年第3期192-200,共9页
This paper analyzes Chinese household CO_2 emissions in 1994-2012 based on the Logarithmic Mean Divisia Index(LMDI) structure decomposition model, and discusses the relationship between household CO_2 emissions and ec... This paper analyzes Chinese household CO_2 emissions in 1994-2012 based on the Logarithmic Mean Divisia Index(LMDI) structure decomposition model, and discusses the relationship between household CO_2 emissions and economic growth based on a decoupling indicator.The results show that in 1994-2012, household CO_2 emissions grew in general and displayed an accelerated growth trend during the early 21 st century. Economic growth leading to an increase in energy consumption is the main driving factor of CO_2 emission growth(an increase of 1.078 Gt CO_2) with cumulative contribution rate of 55.92%, while the decline in energy intensity is the main cause of CO_2 emission growth inhibition(0.723 Gt CO_2 emission reduction) with cumulative contribution rate of 38.27%. Meanwhile, household CO_2 emissions are in a weak state of decoupling in general. The change in CO_2 emissions caused by population and economic growth shows a weak decoupling and expansive decoupling state, respectively. The CO_2 emission change caused by energy intensity is in a state of strong decoupling, and the change caused by energy consumption structure ?uctuates between a weak and a strong decoupling state. 展开更多
关键词 HOUSEHOLD energy CONSUMPTION CO2 emissions LMDI model decoupling INDICATOR
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The decoupling relationship between China’s economic growth and carbon emissions from the perspective of industrial structure 被引量:4
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作者 Yuwei Du Yunxi Liu +1 位作者 Md.Afzal Hossain Songsheng Chen 《Chinese Journal of Population,Resources and Environment》 2022年第1期49-58,共10页
This study analyses the decoupling relationship between energy-related CO_(2) emissions and economic growth in China from 2000-2017 from the perspective of industrial structure using the LMDI method and Tapio decoupli... This study analyses the decoupling relationship between energy-related CO_(2) emissions and economic growth in China from 2000-2017 from the perspective of industrial structure using the LMDI method and Tapio decoupling model.The decoupling driving force was decomposed into emission,energy intensity,industrial structure,economic activity,and population factors.Studies have shown that the restructuring of China’s industries has not led to a significant increase in CO_(2) emissions.Specifically,from 2000 to 2017,China’s economic development and carbon emissions are generally in a weak decoupling state.Strong decoupling occurred from 2000 to 2001 and from 2013 to 2016.The industrial structure change has a substantial impact on the primary sector(agriculture),followed by the tertiary sector(services),while the impact on the secondary sector(industry)is negligible.The GDP contribution of the primary industry is small,but it is an indispensable guarantee for a country.With the development of agricultural mechanization and technology,human and animal power in this industry has been decreasing year by year,and large-scale planting has improved energy efficiency.The level of technology should be continuously strengthened to promote the decoupling of carbon emissions.The contribution of the secondary industry to GDP is around 40%,but the secondary industry accounts for more than 80%of CO_(2) emissions,mainly caused by the use of fossil energy.In 2017,fossil energy still accounted for about 86.2%of China’s energy consumption,so fossil energy remains the most critical energy source for China’s economic development.Coal,in turn,accounts for the largest share of fossil energy consumption.Therefore,emphasis should be placed on increasing technological innovation and conversion from fossil to non-fossil energy sources.The Chinese government considers the service industry a new engine for sustainable social and economic development.The contribution of the tertiary sector to GDP has increased from 2000 to 2017,followed by resource and environmental problems.Although the current share of CO_(2) emissions directly caused by the tertiary sector is not high,as the tertiary sector continues to grow,plans to reduce the decoupling of carbon emissions from the tertiary sector should be made in advance. 展开更多
关键词 China Economic growth Carbon emission LMDI Tapio model decoupling
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Multi-parameter decoupling and slope tracking control strategy of a large-scale high altitude environment simulation test cabin 被引量:7
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作者 Li Ke Liu Wangkai +2 位作者 Wang Jun Huang Yong Liu Meng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1390-1400,共11页
A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic co... A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic control of the temperature–pressure two-parameter and overcome the control difficulties inherent to a large inertia lag link with a complex control system which is composed of turbine refrigeration device, vacuum device and liquid nitrogen cooling device. The system includes multi-parameter decoupling of the cabin itself to avoid equipment damage of air refrigeration turbine caused by improper operation. Based on analysis of the dynamic characteristics and modeling for variations in temperature, pressure and rotation speed, an intelligent controller was implemented that includes decoupling and fuzzy arithmetic combined with an expert PID controller to control test parameters by decoupling and slope tracking control strategy. The control system employed centralized management in an open industrial ethernet architecture with an industrial computer at the core. The simulation and field debugging and running results show that this method can solve the problems of a poor anti-interference performance typical for a conventional PID and overshooting that can readily damage equipment. The steady-state characteristics meet the system requirements. 展开更多
关键词 decoupling control Environment cabin Fuzzy control Liquid nitrogen Mathematical model Vacuum
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Precise control of a magnetically suspended double-gimbal control moment gyroscope using differential geometry decoupling method 被引量:3
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作者 Chen Xiaocen Chen Maoyin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第4期1017-1028,共12页
Precise control of a magnetically suspended double-gimbal control moment gyroscope (MSDGCMG) is of vital importance and challenge to the attitude positioning of spacecraft owing to its multivariable, nonlinear and s... Precise control of a magnetically suspended double-gimbal control moment gyroscope (MSDGCMG) is of vital importance and challenge to the attitude positioning of spacecraft owing to its multivariable, nonlinear and strong coupled properties. This paper proposes a novel linearization and decoupling method based on differential geometry theory and combines it with the internal model controller (IMC) to guarantee the system robustness to the external disturbance and parameter uncertainty. Furthermore, by introducing the dynamic compensation for the inner-gimbal rate-servo system and the magnetically suspended rotor (MSR) system only, we can eliminate the influence of the unmodeled dynamics to the decoupling control accuracy as well as save costs and inhibit noises effectively. The simulation results verify the nice decoupling and robustness performance of the system using the proposed method. 展开更多
关键词 Differential geometry decoupling Dynamic compensation Internal model controller MSDGCMG Spacecraft control
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DECOUPLED MODEL FOR FLATNESS CONTROL IN 4-H CVC COLD ROLLING MILLS
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作者 Zhong Jue and Chen Jie College of Mechanical and Electrical Engineering, Central South University of Technology, Changsha 410083, P. R. China 《中国有色金属学会会刊:英文版》 CSCD 1998年第4期185-187,共3页
INTRODUCTIONTheprecisecontrolofrolgapin4hCVCmilsisparticularlydificultduetothecomplexinteractionsbetwenworkr... INTRODUCTIONTheprecisecontrolofrolgapin4hCVCmilsisparticularlydificultduetothecomplexinteractionsbetwenworkrolshiftingandben... 展开更多
关键词 decoupled model gage and shape CONTROL COLD ROLLING
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Decoupling Algorithms for the Gravitational Wave Spacecraft
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作者 XueWang Weizhou Zhu +4 位作者 Zhao Cui Xingguang Qian Jinke Yang Jianjun Jia Yikun Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期325-337,共13页
The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precis... The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precision control.Establishing one spacecraftwith two laser links,compared to one spacecraft with a single laser link,requires an upgraded decoupling algorithmfor the link establishment.The decoupling algorithmwe designed reassigns the degrees of freedomand forces in the control loop to ensure sufficient degrees of freedomfor optical axis control.In addressing the distinct dynamic characteristics of different degrees of freedom,a transfer function compensation method is used in the decoupling process to further minimize motion coupling.The open-loop frequency response of the systemis obtained through simulation.The upgraded decoupling algorithms effectively reduce the open-loop frequency response by 30 dB.The transfer function compensation method efficiently suppresses the coupling of low-frequency noise. 展开更多
关键词 Gravitational waves spacecraft laser acquisition decoupling algorithms dynamical model optical axis control
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Asian Trade Integration and the Decoupling Debate of Business Cycles
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作者 Linyue Li 《Chinese Business Review》 2016年第4期172-185,共14页
"Decoupling" refers to the divergence of business cycles among different countries, while "re-coupling" corresponds to the convergence or the synchronization of business cycles among different countries. The decou... "Decoupling" refers to the divergence of business cycles among different countries, while "re-coupling" corresponds to the convergence or the synchronization of business cycles among different countries. The decoupling debate is popular in the field of economics, especially after global financial crisis. As trade integration increased among Asian countries, business cycle synchronization among these countries was expected to increase through trade transmission. The aim of this study is to discover whether there has been decoupling or convergence of business cycles through various trade channels. However, theoretically, increased trade can lead to business cycle synchronization either rising or falling. Inter-industry trade resulting in higher specification will induce less synchronized business cycles, while intra-industry trade could lead to increased business cycle synchronization. Thus, it is important to distinguish between intra- and inter-industry trade flows. Both correlation and dynamic factor models are utilized to study the evolution of global business cycle linkages. Results indicate that the world factor has become less important in explaining macroeconomic fluctuations from sub-period 1961-1984 to sub-period 1985-2007, while regional factors do not play an important role in explaining aggregate volatility, with the expectation of consumption. Overall, the explanatory power of country factors increases. Domestic consumption and domestic investment variances are more driven by country and idiosyncratic factors than by the world factor, contrary to the output growth fluctuations. Regional factors and country factors also play a more prominent role in explaining gross import fluctuations than in explaining gross exports. Results cast doubt on the strong forms of both the decoupling and the re-coupling hypothesis. 展开更多
关键词 trade integration decoupling business cycle dynamic factor model world factor
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Minimally deformed anisotropic version of Tolman-Finch-Skea stellar model in Einstein-Gauss-Bonnet gravity
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作者 Hina Azmat Rafia Khalid +2 位作者 M Zubair Emre Demir Ertan Gudekli 《Communications in Theoretical Physics》 2025年第6期133-148,共16页
In this article,a well-known anisotropic solution,the Tolman-Finch-Skea(TFS)solution,is studied using the gravitational decoupling approach within the framework of 4D Einstein-Gauss-Bonnet(EGB)gravity.The radial metri... In this article,a well-known anisotropic solution,the Tolman-Finch-Skea(TFS)solution,is studied using the gravitational decoupling approach within the framework of 4D Einstein-Gauss-Bonnet(EGB)gravity.The radial metric potential is modified linearly through the minimal geometric deformation approach,while the temporal component of the metric remains unchanged.The system of EGB field equations is decomposed into two distinct sets of field equations:one corresponding to the standard energy-momentum tensor and the other associated with an external gravitational source.The first system is solved using the aforementioned known solution,while the second is closed by imposing the mimic constraint on pressure.Moreover,the junction conditions at the inner and outer surfaces of the stellar object are examined,considering the Boulware-Deser 4D space-time as the external geometry.The physical properties of the stellar model are analyzed using parameters such as energy conditions,causality conditions,compactness,and redshift. 展开更多
关键词 Einstein-Gauss-Bonnet gravity stellar model Tolman-Finch-Skea solution gravitational decoupling
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黄河流域农业碳排放脱钩效应及影响因素研究 被引量:1
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作者 初丽霞 王文燕 《生态经济》 北大核心 2026年第1期67-75,共9页
采用碳排放系数法测算2000—2022年黄河流域农业碳排放,并运用Tapio脱钩模型和LMDI模型分别分析其与农业经济发展水平的关系和影响因素。结果表明:2000—2022年黄河流域农业碳排放整体呈现先上升后下降的趋势,碳排放强度呈波动下降趋势... 采用碳排放系数法测算2000—2022年黄河流域农业碳排放,并运用Tapio脱钩模型和LMDI模型分别分析其与农业经济发展水平的关系和影响因素。结果表明:2000—2022年黄河流域农业碳排放整体呈现先上升后下降的趋势,碳排放强度呈波动下降趋势,并且畜禽养殖是农业碳排放的主要来源,山东、河南是农业碳排放的主要贡献省份。在脱钩关系上,黄河流域整体农业碳排放与农业经济增长间呈现强弱脱钩交替的有利状态,各省份脱钩状态存在差异。影响因素方面,在时序分解和区域比较上均表现为农业经济发展水平为农业碳排放的增排因素,而农业生产效率是第一抑制因素。可以通过推广低碳农业发展方式、实施分区精准治理及加强碳排放驱动因素管理等措施来减少黄河流域农业碳排放。 展开更多
关键词 农业碳排放 Tapio脱钩 LMDI模型 黄河流域
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智能汽车信息物理系统研究进展
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作者 孙棣华 蒋胜龙 +5 位作者 高博麟 赵敏 林景栋 肖雅月 梁浩 李克强 《汽车工程》 北大核心 2026年第2期235-248,共14页
智能汽车信息物理系统(intelligent vehicle cyber-physical systems,IVCPS)是融合多信息物理异构主体的一类复杂系统,体现了汽车智能化、网联化变革的发展方向和关键技术特征。本文探讨了IVCPS的定义与内涵、系统特征及其研发路径,梳... 智能汽车信息物理系统(intelligent vehicle cyber-physical systems,IVCPS)是融合多信息物理异构主体的一类复杂系统,体现了汽车智能化、网联化变革的发展方向和关键技术特征。本文探讨了IVCPS的定义与内涵、系统特征及其研发路径,梳理了其体系架构、建模方法、设计方法及验证与确认等关键技术的研究进展,并结合智慧公交应用进行了案例分析。最后,总结了IVCPS在协同机制、模型对齐、信息物理同步、测试验证及信息安全等方面的主要挑战与发展趋势,为相关研究和工程实践提供参考。 展开更多
关键词 信息物理系统 智能汽车 基于模型的系统工程 系统之系统 分层解耦 跨域协同
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大秦岭地区县域土地利用碳排放与生态环境质量脱钩关系
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作者 马超群 杨天丽 +3 位作者 员学锋 王晓峰 任朝霞 任晨辰 《水土保持研究》 北大核心 2026年第2期302-313,共12页
[目的]土地利用碳排放与生态环境质量之间保持强脱钩是实现“双碳”目标的重要途径,明晰二者关系对深入理解区域可持续发展具有重要意义。[方法]以大秦岭地区县域尺度视角,基于土地利用数据、ODIAC数据和MODIS数据,分析了2000—2020年... [目的]土地利用碳排放与生态环境质量之间保持强脱钩是实现“双碳”目标的重要途径,明晰二者关系对深入理解区域可持续发展具有重要意义。[方法]以大秦岭地区县域尺度视角,基于土地利用数据、ODIAC数据和MODIS数据,分析了2000—2020年土地利用引起的碳排放和地区生态环境质量的时空演变特征,并借助脱钩模型探究二者在20年间的演变过程。[结果](1)大秦岭地区土地利用类型时空变化显著,建设用地面积持续增加。(2)地区土地利用碳排放总量从2000年的1.57×10^(7)t增加至2020年5.31×10^(7)t,历经“快速增长—缓慢增长”两个阶段;碳排放量重心向西迁移后保持稳定。(3)地区生态环境质量时间上呈“波动下降—波动上升—波动下降”的演变过程,多年均值为0.63,生态环境质量整体较高;空间分布上呈现“中间好、四周差”的特征。(4)20年间,大秦岭地区县域土地利用碳排放与生态环境质量脱钩关系呈现显著的时空异质性,时间上呈现出“恶化—改善—恶化”的变化过程;空间上以负脱钩为主,各县脱钩进程不一,存在显著的县际差异。[结论]土地利用碳排放对生态环境质量潜在威胁较大,研究结果可为各区县因地制宜管理土地利用碳排放,实现绿色高质量发展提供政策参考。 展开更多
关键词 土地利用碳排放 生态环境质量 脱钩模型 大秦岭地区 县域尺度
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东北黑土区种植业碳排放脱钩效应及驱动因素研究——基于Tapio脱钩模型和LMDI分析
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作者 高玉娟 熊子姁 《生态经济》 北大核心 2026年第3期174-183,共10页
在“双碳”目标背景下,探究种植业碳排放脱钩效应及驱动因素,为推进农业高质量发展提供重要支撑。在科学构建种植业碳排放核算指标体系的基础上,采用碳排放因子法对2010—2022年东北黑土区种植业碳排放总量进行测算;运用Tapio脱钩模型和... 在“双碳”目标背景下,探究种植业碳排放脱钩效应及驱动因素,为推进农业高质量发展提供重要支撑。在科学构建种植业碳排放核算指标体系的基础上,采用碳排放因子法对2010—2022年东北黑土区种植业碳排放总量进行测算;运用Tapio脱钩模型和LMDI模型,探究种植业碳排放脱钩效应及驱动因素,并对2023—2035年种植业碳排放趋势进行预测。研究结果表明:(1)近年来东北黑土区种植业碳排放总量及强度呈现波动递减趋势,农用物资是其最主要的碳源。(2)种植业碳排放与农业产值的脱钩关系呈现“弱脱钩—弱负脱钩—强脱钩”的变化历程。同时,经济发展水平、城镇化水平与农业产业结构对种植业碳排放起正向影响,种植业生产效率和劳动力规模对种植业碳排放起负向影响。(3)2022—2035年东北黑土区种植业碳排放量将持续下降,并于2030年前达到峰值。因此,通过提升黑土地固碳水平、加强技术创新和结构优化、转移农业剩余劳动力,实现种植业低碳化可持续发展。 展开更多
关键词 种植业碳排放 Tapio脱钩模型 LMDI模型 灰色预测模型 东北黑土区
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掺氢天然气管道仿真方法研究
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作者 田晓龙 杨罗 +2 位作者 吴小平 代明亮 江明 《北京化工大学学报(自然科学版)》 北大核心 2026年第1期40-50,共11页
迄今,掺氢天然气的仿真工作始终无法有效平衡计算精度和仿真速度这2项参数,不利于指导现场运行方案的快速决策。针对这一问题,将组分追踪方程、水力方程和热力方程进行去耦仿真,分析了耦合模型与气体瞬态管网模拟软件TGNET结果、耦合模... 迄今,掺氢天然气的仿真工作始终无法有效平衡计算精度和仿真速度这2项参数,不利于指导现场运行方案的快速决策。针对这一问题,将组分追踪方程、水力方程和热力方程进行去耦仿真,分析了耦合模型与气体瞬态管网模拟软件TGNET结果、耦合模型和去耦模型结果的差异性,确定了最优的时间步长和空间步长,引入单指令多数据(SIMD)并行计算技术,基于AVX2指令集实现中间参数求解过程的快速化处理,以实际案例进行了计算和分析。结果显示:耦合模型结果与TGNET软件结果的吻合程度较高,两者的计算时间分别为8237 ms和8359 ms,2种模型具有一致性和相容性;去耦模型计算时采用时间步长90 s、空间步长1 km的组合较为合适,与耦合模型相比,此组合下的加速比为2.89;与最大压力-最大流量边界条件相比,最大流量-最大流量边界条件下的压力、温度、氢气摩尔分数的误差均有所增大,建议在管网规划设计、运行调峰、突发性用气和供气安全冗余保障等工况下优先使用该边界条件;与去耦模型相比,引入SIMD指令的计算加速比为2.68,低于理论加速比上限。研究结果可为大型掺氢天然气管网的仿真工作提供理论依据和实际参考。 展开更多
关键词 掺氢天然气 仿真 耦合模型 去耦模型 边界条件 SIMD
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