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State Estimation of Drive-by-Wire Chassis Vehicle Based on Dual Unscented Particle Filter Algorithm
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作者 Zixu Wang Chaoning Chen +2 位作者 Quan Jiang Hongyu Zheng Chuyo Kaku 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期99-113,共15页
Accurate vehicle dynamic information plays an important role in vehicle driving safety.However,due to the characteristics of high mobility and multiple controllable degrees of freedom of drive-by-wire chassis vehicles... Accurate vehicle dynamic information plays an important role in vehicle driving safety.However,due to the characteristics of high mobility and multiple controllable degrees of freedom of drive-by-wire chassis vehicles,the current mature application of traditional vehicle state estimation algorithms can not meet the requirements of drive-by-wire chassis vehicle state estimation.This paper proposes a state estimation method for drive-by-wire chassis vehicle based on the dual unscented particle filter algorithm,which make full use of the known advantages of the four-wheel drive torque and steer angle parameters of the drive-by-wire chassis vehicle.In the dual unscented particle filter algorithm,two unscented particle filter transfer information to each other,observe the vehicle state information and the tire force parameter information of the four wheels respectively,which reduce the influence of parameter uncertainty and model parameter changes on the estimation accuracy during driving.The performance with the dual unscented particle filter algorithm,which is analyzed in terms of the time-average square error,is superior of the unscented Kalman filter algorithm.The effectiveness of the algorithm is further verified by driving simulator test.In this paper,a vehicle state estimator based on dual unscented particle filter algorithm was proposed for the first time to improve the estimation accuracy of vehicle parameters and states. 展开更多
关键词 Drive-by-wire chassis vehicle Vehicle state estimation dual unscented particle filter Tire force estimation Unscented particle filter
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Combined Estimation of Vehicle Dynamic State and Inertial Parameter for Electric Vehicles Based on Dual Central Difference Kalman Filter Method
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作者 Xianjian Jin Junpeng Yang +3 位作者 Liwei Xu Chongfeng Wei Zhaoran Wang Guodong Yin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期339-354,共16页
Distributed drive electric vehicles(DDEVs)possess great advantages in the viewpoint of fuel consumption,environment protection and traffic mobility.Whereas the effects of inertial parameter variation in DDEV control s... Distributed drive electric vehicles(DDEVs)possess great advantages in the viewpoint of fuel consumption,environment protection and traffic mobility.Whereas the effects of inertial parameter variation in DDEV control system become much more pronounced due to the drastic reduction of vehicle weights and body size,and inertial parameter has seldom been tackled and systematically estimated.This paper presents a dual central difference Kalman filter(DCDKF)where two Kalman filters run in parallel to simultaneously estimate vehicle different dynamic states and inertial parameters,such as vehicle sideslip angle,vehicle mass,vehicle yaw moment of inertia,the distance from the front axle to centre of gravity.The proposed estimation method only integrates and utilizes real-time measurements of hub torque information and other in-vehicle sensors from standard DDEVs.The four-wheel nonlinear vehicle dynamics estimation model considering payload variations,Pacejka tire model,wheel and motor dynamics model is developed,the observability of the DCDKF observer is analysed and derived via Lie derivative and differential geometry theory.To address system nonlinearities in vehicle dynamics estimation,the DCDKF and dual extended Kalman filter(DEKF)are also investigated and compared.Simulation with various maneuvers are carried out to verify the effectiveness of the proposed method using Matlab/Simulink-CarsimR.The results show that the proposed DCDKF method can effectively estimate vehicle dynamic states and inertial parameters despite the existence of payload variations and variable driving conditions.This research provides a boot-strapping procedure which can performs optimal estimation to estimate simultaneously vehicle system state and inertial parameter with high accuracy and real-time ability. 展开更多
关键词 Distributed drive Electric vehicle state observation Inertial parameter dual central difference Kalman filter
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Quantum dual signature scheme based on coherent states with entanglement swapping
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作者 刘佳丽 施荣华 +2 位作者 石金晶 吕格莉 郭迎 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期44-52,共9页
A novel quantum dual signature scheme, which combines two signed messages expected to be sent to two diverse receivers Bob and Charlie, is designed by applying entanglement swapping with coherent states. The signatory... A novel quantum dual signature scheme, which combines two signed messages expected to be sent to two diverse receivers Bob and Charlie, is designed by applying entanglement swapping with coherent states. The signatory Alice signs two different messages with unitary operations(corresponding to the secret keys) and applies entanglement swapping to generate a quantum dual signature. The dual signature is firstly sent to the verifier Bob who extracts and verifies the signature of one message and transmits the rest of the dual signature to the verifier Charlie who verifies the signature of the other message. The transmission of the dual signature is realized with quantum teleportation of coherent states. The analysis shows that the security of secret keys and the security criteria of the signature protocol can be greatly guaranteed.An extensional multi-party quantum dual signature scheme which considers the case with more than three participants is also proposed in this paper and this scheme can remain secure. The proposed schemes are completely suited for the quantum communication network including multiple participants and can be applied to the e-commerce system which requires a secure payment among the customer, business and bank. 展开更多
关键词 quantum dual signature coherent states entanglement swapping quantum communication network
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Reconstructing Dual Loyalties:Interaction between Host States' Perception and Diasporas' Reaction
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作者 He Jingjie 《Contemporary International Relations》 2018年第6期30-45,共16页
This article explores the dynamics of the Diaspora's dual loyalties towards their home countries and host countries by using American Jewry as a case study. It argues that in liberal-democratic states,the shift in... This article explores the dynamics of the Diaspora's dual loyalties towards their home countries and host countries by using American Jewry as a case study. It argues that in liberal-democratic states,the shift in the Diaspora's loyalty towards the homeland vis-à-vis the host land is a result of the change to the host land's perception of where the acceptable boundary of the Diaspora's practice of dual loyalties is, or in other words, to what extent the Diaspora's support of the homeland is perceived to be acceptable by their host land. The reconstruction of this boundary is determined by four factors: the degree of political coordination between home states and host states, the attempt of the home state to mobilize its diasporas, the means advocated and supported by the Diaspora, and the severity of potential consequences due to the Diaspora's action. 展开更多
关键词 dual loyalties Israel the UNITED states the DIASPORA
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Dual Extended Kalman Filter for Combined Estimation of Vehicle State and Road Friction 被引量:20
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作者 ZONG Changfu HU Dan ZHENG Hongyu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期313-324,共12页
Vehicle state and tire-road adhesion are of great use and importance to vehicle active safety control systems. However, it is always not easy to obtain the information with high accuracy and low expense. Recently, man... Vehicle state and tire-road adhesion are of great use and importance to vehicle active safety control systems. However, it is always not easy to obtain the information with high accuracy and low expense. Recently, many estimation methods have been put forward to solve such problems, in which Kalman filter becomes one of the most popular techniques. Nevertheless, the use of complicated model always leads to poor real-time estimation while the role of road friction coefficient is often ignored. For the purpose of enhancing the real time performance of the algorithm and pursuing precise estimation of vehicle states, a model-based estimator is proposed to conduct combined estimation of vehicle states and road friction coefficients. The estimator is designed based on a three-DOF vehicle model coupled with the Highway Safety Research Institute(HSRI) tire model; the dual extended Kalman filter (DEKF) technique is employed, which can be regarded as two extended Kalman filters operating and communicating simultaneously. Effectiveness of the estimation is firstly examined by comparing the outputs of the estimator with the responses of the vehicle model in CarSim under three typical road adhesion conditions(high-friction, low-friction, and joint-friction). On this basis, driving simulator experiments are carried out to further investigate the practical application of the estimator. Numerical results from CarSim and driving simulator both demonstrate that the estimator designed is capable of estimating the vehicle states and road friction coefficient with reasonable accuracy. The DEKF-based estimator proposed provides the essential information for the vehicle active control system with low expense and decent precision, and offers the possibility of real car application in future. 展开更多
关键词 vehicle state road friction coefficient ESTIMATION dual extended Kalman filter (DEKF)
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Vehicle State and Parameter Estimation Based on Dual Unscented Particle Filter Algorithm 被引量:4
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作者 林棻 王浩 +2 位作者 王伟 刘存星 谢春利 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第5期568-575,共8页
Acquisition of real-time and accurate vehicle state and parameter information is critical to the research of vehicle dynamic control system.By studying the defects of the former Kalman filter based estimation method,a... Acquisition of real-time and accurate vehicle state and parameter information is critical to the research of vehicle dynamic control system.By studying the defects of the former Kalman filter based estimation method,a new estimating method is proposed.First the nonlinear vehicle dynamics system,containing inaccurate model parameters and constant noise,is established.Then a dual unscented particle filter(DUPF)algorithm is proposed.In the algorithm two unscented particle filters run in parallel,states estimation and parameters estimation update each other.The results of simulation and vehicle ground testing indicate that the DUPF algorithm has higher state estimation accuracy than unscented Kalman filter(UKF)and dual extended Kalman filter(DEKF),and it also has good capability to revise model parameters. 展开更多
关键词 vehicle dynamics dual unscented particle filter(DUPF) state estimation virtual experiment
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An all-solid-state high power quasi-continuous-wave tunable dual-wavelength Ti:sapphire laser system using birefringence filter 被引量:1
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作者 丁欣 马洪梅 +4 位作者 邹雷 邹跃 温午麒 王鹏 姚建铨 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1991-1995,共5页
This paper describes a tunable dual-wavelength Ti:sapphire laser system with quasi-continuous-wave and high-power outputs. In the design of the laser, it adopts a frequency-doubled Nd:YAG laser as the pumping source... This paper describes a tunable dual-wavelength Ti:sapphire laser system with quasi-continuous-wave and high-power outputs. In the design of the laser, it adopts a frequency-doubled Nd:YAG laser as the pumping source, and the birefringence filter as the tuning element. Tunable dual-wavelength outputs with one wavelength range from 700 nm to 756.5 nm, another from 830 nm to 900mn have been demonstrated. With a pump power of 23 W at 532 nm, a repetition rate of 7 kHz and a pulse width of 47.6 ns, an output power of 5.1 W at 744.8 nm and 860.9 nm with a pulse width of 13.2 ns and a line width of 3 nm has been obtained, it indicates an optical-to-optical conversion efficiency of 22.2%. 展开更多
关键词 ALL-SOLID-state dual-WAVELENGTH Ti:sapphire laser birefringence filter
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Study on Factors Influencing Urban-rural Dual Economic Structure of Chongqing Based on the State Space Variable Parameter Method
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作者 Xiuchuan XU Yuqing WANG Xiang HE 《Asian Agricultural Research》 2013年第11期9-13,共5页
Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects... Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects factors and variables influencing urban and rural dual economic structure,and establishes an econometric model.By state space Kalman filtering method,it analyzes dynamic influence of factors upon urban-rural dual economic intensity.According to empirical conclusion,it puts forward corresponding policy recommendations for promoting integrated urban and rural economic development of Chongqing. 展开更多
关键词 URBAN and RURAL dual ECONOMIC structure state SPAC
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Steady State Analysis of an Isolated Self-Excited Dual Three-Phase Induction Generator for Renewable Energy
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作者 Mohamed Arbi Khlifi Badr M. Alshammari 《International Journal of Modern Nonlinear Theory and Application》 2014年第5期191-198,共8页
In this paper modelling and analysis in autonomous mode of dual three-phase induction generator (DTPIG) with a new algorithm have been done. We develop the steady state model of a dual three-phase self-excited inducti... In this paper modelling and analysis in autonomous mode of dual three-phase induction generator (DTPIG) with a new algorithm have been done. We develop the steady state model of a dual three-phase self-excited induction generator for stand-alone renewable generation dispensing with the segregating real and imaginary components of the complex impedance of the induction generator. The obtained admittance yields the adequate magnetizing reactance and the frequency. These two key parameters are then used to compute the self-excitation process requirements in terms of the prime mover speed, the capacitance and the load impedance on the one hand and to predict the generator steady state performance parameters on the other. Steady state performances and characteristics of different configurations are clearly examined and compared. The analytical results are found to be in good agreement with experimental results. 展开更多
关键词 dual STATOR WINDINGS Asynchronous Generator Autonomous Mode STEADY state Analysis RENEWABLE Electric Energy Generation
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融合时间序列趋势的Dual-ESN机组负荷预测模型 被引量:2
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作者 樊建升 吴海滨 刘泽军 《电力系统及其自动化学报》 CSCD 北大核心 2023年第1期152-158,共7页
针对传统模型在机组负荷预测中无法充分捕获内部多变量演化模式的问题,提出了一种基于时间序列的趋势和数值信息融合的双重回声状态网络Dual-ESN(dual-echo state network)机组负荷动态预测模型。首先,引入最小二乘法,对相关的多元历史... 针对传统模型在机组负荷预测中无法充分捕获内部多变量演化模式的问题,提出了一种基于时间序列的趋势和数值信息融合的双重回声状态网络Dual-ESN(dual-echo state network)机组负荷动态预测模型。首先,引入最小二乘法,对相关的多元历史信息按照局部时间跨度进行趋势拟合。进一步,得到有关过程变化的模式序列,并和原本的数值分别被送入两个独立的储备池,以并行的时间维度进行特征学习。其次,将隐层的高维空间状态送入输出层,融合信息,得到所需要的预测结果。最后,基于山西某工厂660 MW机组装置的真实数据集,进行验证。对比已有预测方法,结果表明所提预测模型在多种性能指标上均有提升。 展开更多
关键词 机组负荷预测 双重回声状态网络 时间序列趋势 最小二乘法
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国有企业的低碳双元战略发展路径——基于上海申通地铁集团的案例研究 被引量:2
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作者 俞光耀 郑琴琴 +1 位作者 赵优珍 岳章 《研究与发展管理》 CSSCI 北大核心 2024年第1期27-39,共13页
在中国特色社会主义经济制度下,国有企业始终肩负着发展经济和服务社会的双重使命。根据企业所处的行业特点与所承担的业务特征,国有企业很可能面临高耗能的挑战。选取上海申通地铁集团有限公司作为典型案例,基于双元理论探究国有企业... 在中国特色社会主义经济制度下,国有企业始终肩负着发展经济和服务社会的双重使命。根据企业所处的行业特点与所承担的业务特征,国有企业很可能面临高耗能的挑战。选取上海申通地铁集团有限公司作为典型案例,基于双元理论探究国有企业低碳双元战略的动态发展路径。研究发现,国有企业的低碳发展首先是将低碳理念融入其“经济—社会”双元目标,形成具有经济属性的成本性和效益性低碳导向,以及具有社会属性的政策性和公益性低碳导向。基于此,国有企业开发低碳双元战略实践,包括具有经济属性的低碳成本管理和低碳业务投资,以及具有社会属性的低碳政策落实和产业低碳引领。此外,知识和资源开发促进了低碳双元战略实践的相互转化,实现了低碳双元战略的协调统一。研究结论既为国有企业低碳发展中的协同辩证关系提供了新的理解,又拓展了双元理论在企业低碳管理领域的应用。 展开更多
关键词 国有企业 双元目标 低碳战略 案例研究
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基于双重约束的并网逆变器电流自动化控制方法研究
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作者 陈志刚 高冰 +1 位作者 李滨 杨晓磊 《自动化与仪表》 2024年第2期30-34,共5页
为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函... 为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函数;采用输出电流直接前馈的改进阻尼控制方法实现电流自动化控制,并引入全局-局部稳定双重约束原则,确定最佳的谐振抑制参数,提升电流的控制效果。测试结果显示,该方法的并网逆变器的电流畸变率均低于5%,电流跳变过程中,可在0.2 s内有效控制跳变电流结果。 展开更多
关键词 双重约束 并网逆变器 自动化控制 谐振抑制参数 增益函数 运行状态
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双重衔接:国家治理与社会科学研究
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作者 方长春 《学术前沿》 CSSCI 北大核心 2024年第14期92-99,共8页
国家治理离不开对经验事实的分析与研判。自党的十八届三中全会以来,推进国家治理体系和治理能力现代化不仅在政策实践层面受到高度重视,也得到了社会科学研究的广泛关注。当前,我国在治理实践和社会科学研究中存在着双重衔接不足:一是... 国家治理离不开对经验事实的分析与研判。自党的十八届三中全会以来,推进国家治理体系和治理能力现代化不仅在政策实践层面受到高度重视,也得到了社会科学研究的广泛关注。当前,我国在治理实践和社会科学研究中存在着双重衔接不足:一是治理实践与经验性社会科学研究的衔接不足,二是社会科学中的“应然”研究与“实然”研究的衔接不足。强化“双重衔接”,一是要强化国家治理的经验事实之基,二是要强化对当代中国经济社会运行中社会事实“是什么”、“为什么”和“将会怎样”的科学研究,并将对策研究和治理实践建基于这些科学研究的基础之上。 展开更多
关键词 国家治理 社会科学研究 双重衔接
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论生态环境损害赔偿制度的法理基础与规范构造
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作者 张忠民 《现代法学》 CSSCI 北大核心 2024年第4期131-145,共15页
理解生态环境损害赔偿制度,须从环境治理体系和治理能力现代化的整体视域展开,同时,还要厘清生态环境与自然资源、生态环境损害与损害赔偿、赔偿请求权与赔偿诉权等核心概念。既有理论将自然资源国家所有权作为生态环境损害赔偿中的实... 理解生态环境损害赔偿制度,须从环境治理体系和治理能力现代化的整体视域展开,同时,还要厘清生态环境与自然资源、生态环境损害与损害赔偿、赔偿请求权与赔偿诉权等核心概念。既有理论将自然资源国家所有权作为生态环境损害赔偿中的实体权利基础,然而,不论是公权说、私权说,还是二阶结构说、三层结构说,都不周延。因为生态环境损害赔偿制度存在二元构造,即赔偿请求权区别于赔偿诉权,赔偿请求权中基于自然资源所有权的物上请求权区别于侵害生态环境的侵权之债请求权,赔偿诉权中程序意义上的提起生态环境损害赔偿诉讼区别于实体意义上的救济自然资源所有权。这种二元构造客观上源于生态环境中单体自然资源的结构面向与整体生态功能的功能面向存在区分,其学理基础在于承继和发展了传统所有权的解释范式,其核心内容是对生态环境类的损害进行类型化。为此,该制度可从两个方面予以展开。长期而言,须仰仗制定中的生态环境法典规定生态环境损害赔偿的系列内容;当务之急,则是借助司法解释促进这些内容的适度法制化。 展开更多
关键词 赔偿请求权 赔偿诉权 自然资源国家所有 二元构造 生态环境法典
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架起政府与市场的桥梁:地方国企的“经纪”行为
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作者 刘伟 陈春润 《甘肃行政学院学报》 CSSCI 2024年第3期57-69,126,共14页
地方国企在国民经济体系中占据着举足轻重的地位,其在中国经济发展中的行为备受瞩目。在国家级开发区的发展案例中发现,地方国企展现出桥接地方政府和市场主体的“经纪”行为。地方国企代理着地方政府和市场主体的双重利益,桥接了地方... 地方国企在国民经济体系中占据着举足轻重的地位,其在中国经济发展中的行为备受瞩目。在国家级开发区的发展案例中发现,地方国企展现出桥接地方政府和市场主体的“经纪”行为。地方国企代理着地方政府和市场主体的双重利益,桥接了地方政府和市场主体。在这之中,地方国企表现出举荐可靠项目、激发致富渴望、监督履行承诺、增进政商沟通等“经纪”行为,为地方政府和市场主体架起了一座桥梁,促进了双方利益整合。地方国企的“经纪”行为之所以奏效,归功于地方国企在地方政府和市场主体之间建立起信任,赋予双方对彼此的主观确定性,从而改变了限制和机会。地方国企也从中谋求到更多的发展机遇。归根结底,地方国企所呈现的“经纪”行为填补了既有制度下连接地方政府与市场主体的真空。地方国企的“经纪”行为为理解其在中国经济发展中的作用提供了新的解释。这一非正式的桥接机制在一定程度上帮助地方政府和市场主体克服了不确定性难题。 展开更多
关键词 地方国企 地方政府 市场主体 双重利益代理 “经纪”行为
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“双碳”目标下国有炼化企业管理效益审计优化研究
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作者 孙仁金 官栋 胡启迪 《国际石油经济》 2024年第4期92-98,共7页
碳达峰、碳中和目标提出后,国有炼化企业的审计工作被赋予了“绿色环保+管理效益”的全新定位。国有炼化企业管理效益审计存在未包含“双碳”相关指标、业务单元与审计责任边界亟需厘清、业务绩效与审计监督结合有待深化、管理效益审计... 碳达峰、碳中和目标提出后,国有炼化企业的审计工作被赋予了“绿色环保+管理效益”的全新定位。国有炼化企业管理效益审计存在未包含“双碳”相关指标、业务单元与审计责任边界亟需厘清、业务绩效与审计监督结合有待深化、管理效益审计人员认识有待提高等问题。提出了形成低碳发展的审计理念和制度体系,构建节能减排、控碳的绿色发展指标体系,优化碳排放核算、定额和计量标准,完善审计报告发布和披露内容等对策建议。 展开更多
关键词 “双碳”目标 管理效益审计 审计优化 国有炼化企业
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一种动态锁定式多星协同任务规划的A2C算法
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作者 张晋 赵雪婷 李博文 《宇航学报》 EI CAS CSCD 北大核心 2024年第5期700-710,共11页
提出了一种基于强化学习算法的多星协同任务规划方法。该方法将多星协同任务规划视为多个双星协同规划,采用相邻双星锁定的方式来共享双星任务规划结果信息,基于A2C(优势动作评价)强化学习算法对双星任务规划的结果进行再调整。针对多... 提出了一种基于强化学习算法的多星协同任务规划方法。该方法将多星协同任务规划视为多个双星协同规划,采用相邻双星锁定的方式来共享双星任务规划结果信息,基于A2C(优势动作评价)强化学习算法对双星任务规划的结果进行再调整。针对多星协同任务规划状态空间复杂且变化的问题,设计了两级状态空间和价值评价函数决策的方法,对强化学习所依赖的状态空间进行维度限制,确保智能体对任务进行调整的过程不影响状态空间维度。算法设计过程考虑了多种约束条件,设置了天气、成像质量和成像优先级等可调参数作为强化学习A2C算法的评价参数,这些可调参数有助于用户自定义决策评价体系。最后,通过仿真验证了算法的可行性。仿真结果表明,该算法多星协同任务规划的组合任务抛弃率小于10%。 展开更多
关键词 多星协同任务规划 双星锁定 任务调整 两级状态空间 强化学习
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双暗示性心理护理对进行鼻内镜检查患者应对方式及心理应激的影响 被引量:1
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作者 李晓玲 黄维平 许欢 《黑龙江医学》 2024年第3期346-348,共3页
目的:观察双暗示性心理护理对进行鼻内镜检查患者应对方式及心理应激的影响。方法:选取2019年5月—2021年11月于南阳市中心医院接受鼻内镜检查的135例患者作为研究对象,采用随机数表法将其分为干预组(68例)和对照组(67例)。对照组给予... 目的:观察双暗示性心理护理对进行鼻内镜检查患者应对方式及心理应激的影响。方法:选取2019年5月—2021年11月于南阳市中心医院接受鼻内镜检查的135例患者作为研究对象,采用随机数表法将其分为干预组(68例)和对照组(67例)。对照组给予常规护理,干预组给予双暗示性心理护理。比较两组患者应对方式、心理状态以及配合度评分,并观察患者心理应激情况。结果:干预组患者面对评分显著高于对照组,回避、屈服评分显著低于对照组,差异有统计学意义(t=3.651、2.790、3.120,P<0.05);干预后,两组患者评分均降低,且干预组焦虑自评量表(SAS)、抑郁自评量表(SDS)评分显著低于对照组,差异有统计学意义(t=3.040、3.274,P<0.05);干预组患者主动配合度显著高于对照组(χ^(2)=4.595,P<0.05);干预后,两组患者心率(HR)、收缩压、舒张压水平均降低,且干预组患者各项指标均显著低于对照组,差异有统计学意义(t=2.567、2.449、2.735,P<0.05)。结论:双暗示性心理护理应用于鼻内镜检查,可较好地减轻患者负面情绪,降低心理应激,促使其积极面对检查,提高配合度。 展开更多
关键词 双暗示性心理护理 鼻内镜检查 心理状态 配合度
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双循环背景下城市群的空间重构与规划应对——基于新国家空间理论
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作者 鲁亚楠 施德浩 +3 位作者 张衔春 许顺才 刘斌 岳文泽 《城市规划》 CSSCI CSCD 北大核心 2024年第8期16-24,66,共10页
基于新国家空间理论,构建了“资本循环-空间建构-规划应对”的分析框架,审视由“外循环”向“双循环”转变过程中城市群的空间重构需求,提出相应的规划编制策略。研究发现:双循环新发展格局下,中国城市群在全球、国家和区域尺度均面临... 基于新国家空间理论,构建了“资本循环-空间建构-规划应对”的分析框架,审视由“外循环”向“双循环”转变过程中城市群的空间重构需求,提出相应的规划编制策略。研究发现:双循环新发展格局下,中国城市群在全球、国家和区域尺度均面临多重挑战。现阶段中国19个国家级城市群在经济循环中需担任不同的角色:成熟型城市群参与外循环,发展型城市群驱动内循环,培育型城市群组织微循环。为实现城市群空间重构,3种类型的城市群需有不同的国家空间工程构建逻辑和规划传导原则,以及国家空间策略部署途径和规划编制重点。本文的研究结果填补了空间规划服务于国家新发展格局的理论空白,从城市群角度为双循环战略提供重要理论和规划支撑。 展开更多
关键词 双循环 城市群 空间重构 新国家空间 空间规划
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双星跟飞测高卫星在轨初步验证
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作者 孙中苗 翟振和 +2 位作者 管斌 阮仁桂 黄令勇 《测绘学报》 EI CSCD 北大核心 2024年第2期207-216,共10页
卫星测高反演重力场的常规做法是利用海面高差求解垂线偏差,进一步计算海洋重力异常和海洋大地水准面高等信息。显然,提高海面高差的测量精度可以直接提升海洋重力场的反演精度。本文给出了双星跟飞卫星测高原理,通过轨道设计使双星星... 卫星测高反演重力场的常规做法是利用海面高差求解垂线偏差,进一步计算海洋重力异常和海洋大地水准面高等信息。显然,提高海面高差的测量精度可以直接提升海洋重力场的反演精度。本文给出了双星跟飞卫星测高原理,通过轨道设计使双星星下点跨轨间距(即分辨率)在1′左右,双星同时测量沿其轨道的海面高差及跨轨的星间海面高差,此时轨道径向误差表现为星间或单星历元间的相对轨道径向误差,而与大气传播和地球物理效应等有关的改正项,对于地面轨间距只有1′的双星近似相等,其在海面高差中几无体现,因此海面高差的精度相比于传统的单星测量将有显著提高。利用测高A/B双星的实际观测数据,初步验证了相对轨道径向误差和海面高差中的8项改正的差值误差。结果表明,对于定标阶段约25 km的星下点间距,干对流层、湿对流层、电离层、固体潮、极潮和逆大气压等改正项的差值误差均在5 mm量级;海潮改正差值、海况偏差差值中分别有约1 cm和2 cm的残留误差;对于业务轨道约2 km的星下点间距,相对轨道径向误差约为3 mm,除了海况偏差差值有约0.52 cm的残留误差,其他改正项的差值误差均小于0.05 cm,可完全忽略不计。 展开更多
关键词 卫星测高 双星跟飞测量模式 海洋重力场 垂线偏差 相对定轨 海况偏差
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