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Networked Cooperative Distributed Model Predictive Control Based on State Observer
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作者 Baili Su Yanan Zhao Jinming Huang 《Applied Mathematics》 2016年第10期1148-1164,共17页
Although distributed model predictive control has caused significant attention and received many good results, the results are mostly under the assumption that the system states can be observed. However, the states ar... Although distributed model predictive control has caused significant attention and received many good results, the results are mostly under the assumption that the system states can be observed. However, the states are difficult to be observed in practice. In this paper, a novel distributed model predictive control is proposed based on state observer for a kind of linear discrete-time systems where states are not measured. Firstly, an output feedback control law is designed based on Lyapunov function and state observer. And the stability domain is described. Furthermore, the stability domain as a terminal constraint is added into the constraint conditions of the algorithm to make systems stable outside the stability domain. The simulation results show the effectiveness of the proposed method. 展开更多
关键词 Distributed System Model Predictive Control Lyapunov Function state Observer Stable Domain cooperative Control
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A Method to Obtain the Moving Speed of Uncooperative Target Based on Only Two Measurements
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作者 Tao Yu 《Advances in Aerospace Science and Technology》 2024年第1期1-9,共9页
The existing research results show that a fixed single station must conduct three consecutive frequency shift measurements and obtain the target’s moving speed by constructing two frequency difference equations. This... The existing research results show that a fixed single station must conduct three consecutive frequency shift measurements and obtain the target’s moving speed by constructing two frequency difference equations. This article proposes a new method that requires only two consecutive measurements. While using the azimuth measurement to obtain the angular difference between two radial distances, it also conducts two consecutive Doppler frequency shift measurements at the same target azimuth. On the basis of this measurement, a frequency difference equation is first constructed and solved jointly with the Doppler frequency shift equation. By eliminating the velocity variable and using the measured angular difference to obtain the target’s lead angle, the target’s velocity can be solved by using the Doppler frequency shift equation again. The new method avoids the condition that the target must move equidistantly, which not only provides an achievable method for engineering applications but also lays a good foundation for further exploring the use of steady-state signals to achieve passive positioning. 展开更多
关键词 Moving Speed Non-cooperative Target Doppler Frequency Shift Frequency Difference Equation AZIMUTH Steady-state Signal Passive Location
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Optimization of Dead Load State in Earth-Anchored Cable-Stayed Bridges 被引量:4
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作者 Bin Sun Rucheng Xiao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期87-94,共8页
In order to determine the reasonable completed dead load state in earth-anchored cable-stayed bridges,a practical method is proposed. The method is based on the rigidly supported continuous beam method and the feasibl... In order to determine the reasonable completed dead load state in earth-anchored cable-stayed bridges,a practical method is proposed. The method is based on the rigidly supported continuous beam method and the feasible zone method,emphasizing on the mutual effect between the self-anchored structural parts and the earth-anchored ones. Three cable-stayed bridge models are designed with the main spans of 1 400 m,including a partially earth-anchored cable-stayed bridge,a cable-stayed-suspension bridge and a fully selfanchored cable-stayed bridge,in which the C50 concrete and Q345 steel are adopted. The partially earthanchored cable-stayed bridge and the cable-stayed-suspension bridge secure lower compressive force in the girder than the fully self-anchored cable-stayed bridge by 25 percent at least. The same is for the material consumption of the whole bridge. Furthermore,the anchor volume is more than 20% lower in the partially earthanchored cable-stayed bridge than that in the cable-stayed-suspension bridge. Consequently,the practical span of cable-stayed bridges can be accordingly extended. 展开更多
关键词 cable-stayed BRIDGE partially earth-anchored cable-stayed BRIDGE cable-stayed-suspension BRIDGE REASONABLE completed dead load state
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Cooperative Target Tracking of Multiple Autonomous Surface Vehicles Under Switching Interaction Topologies 被引量:4
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作者 Lang Ma Yu-Long Wang Qing-Long Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期673-684,共12页
This paper is concerned with the cooperative target tracking of multiple autonomous surface vehicles(ASVs)under switching interaction topologies.For the target to be tracked,only its position can be measured/received ... This paper is concerned with the cooperative target tracking of multiple autonomous surface vehicles(ASVs)under switching interaction topologies.For the target to be tracked,only its position can be measured/received by some of the ASVs,and its velocity is unavailable to all the ASVs.A distributed extended state observer taking into consideration switching topologies is designed to integrally estimate unknown target dynamics and neighboring ASVs'dynamics.Accordingly,a novel kinematic controller is designed,which takes full advantage of known information and avoids the approximation of some virtual control vectors.Moreover,a disturbance observer is presented to estimate unknown time-varying environmental disturbance.Furthermore,a distributed dynamic controller is designed to regulate the involved ASVs to cooperatively track the target.It enables each ASV to adjust its forces and moments according to the received information from its neighbors.The effectiveness of the derived results is demonstrated through cooperative target tracking performance analysis for a tracking system composed of five interacting ASVs. 展开更多
关键词 Autonomous surface vehicles(ASVs) cooperative target tracking distributed extended state observer switching topologies
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Influence of the Agreement on Enhancing International Arctic Scientific Cooperation on the approach of non-Arctic states to Arctic scientific activities 被引量:1
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作者 LIU Han 《Advances in Polar Science》 2018年第1期51-60,共10页
As the third legally-binding instrument of the Arctic Council, the Agreement on Enhancing International Arctic Scientific Cooperation was signed in May 2017 and entered into force on 23 May 2018. The Agreement not onl... As the third legally-binding instrument of the Arctic Council, the Agreement on Enhancing International Arctic Scientific Cooperation was signed in May 2017 and entered into force on 23 May 2018. The Agreement not only reduces obstacles to the international scientific cooperation and promotes the movement of people and equipment across borders for the effective and efficient development of Arctic scientific knowledge, but also provides an improved international Arctic legal environment for conducting Arctic scientific cooperation based on UNCLOS and institutional arrangements. However, the observer states, the NGOs and IGOs, as well as Permanent Participants are rarely mentioned in this Agreement. This article chooses one group, non-Arctic states, as a case in point in order to critically discuss the influence of this new Arctic scientific cooperation agreement. It argues that the non-Arctic states are left behind at the original legal situation and trapped in an inferior status in Arctic science. Under these circumstances, this article suggests that non-Arctic states, especially those with competitive research abilities, should appeal for amendment of the Agreement to allow wider access to research areas and data sharing, especially when cooperating with the eight-member states of the Arctic Council. Also, non-Arctic states should take the Agreement as the reference when signing bilateral agreements with Arctic states so as to safeguard their interests when conducting Arctic scientific activities. Moreover, the active participation in other fora as well as various bilateral scientific projects can assist non-Arctic states to strengthen the relations with the Arctic states and build trust in the Arctic Council. 展开更多
关键词 Arctic Council scientific cooperation agreement science diplomacy non-Arctic states Arctic scientific activities Sino-Russian cooperation
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Reflections on the Mechanism of Cooperation between China and Arab States 被引量:2
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作者 Niu Xinchun 《Contemporary International Relations》 2018年第4期40-60,共21页
During the Cold War,China’s diplomacy failed to treat the Arab states as a whole.It was not until the end of the Cold War that China established diplomatic relations with all 22 Arab states.Since then,a multilateral ... During the Cold War,China’s diplomacy failed to treat the Arab states as a whole.It was not until the end of the Cold War that China established diplomatic relations with all 22 Arab states.Since then,a multilateral cooperation mechanism between China and Arab states has come into existence and become steadily developed.In 2004,the China-Arab States Cooperation Forum was established.In 2010,China and the Arab states announced the establishment of a strategic cooperative relationship.After the Gulf War,the Arab world entered a period of fragmentation and division.The situation deteriorated after the drastic changes in the Middle East in 2011,to the point of entering an era of granulation.The ability of The League of Arab States to operate as a single international actor has been greatly impaired.In the era of the fragmentation of the Arab world,the mechanism of multilateral cooperation between China and the Arab States has developed in spite of these great difficulties.In future,the role and function of the multilateral mechanism of cooperation between China and the Arab states needs to be clarified,and efficiency needs to be improved based on the existing mechanisms. 展开更多
关键词 China' s diplomacy the Arab world the China-Arab states cooperation Forum
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Opportunistic best-relay node selection for cooperative transmission improvement over underlay cognitive radio networks
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作者 陈丹 纪红 李曦 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第6期16-21,共6页
In cognitive radio (CR) relay networks,most previous work concentrates on maximizing physical layer quality of service (QoS),e.g.,spectral efficiency and achievable data rate,as relay selection criteria.However,the re... In cognitive radio (CR) relay networks,most previous work concentrates on maximizing physical layer quality of service (QoS),e.g.,spectral efficiency and achievable data rate,as relay selection criteria.However,the residual energy state of relay nodes is largely ignored,which has significant effects on the average network lifetime for those battery-limited wireless networks.In this paper,an opportunistic distributed best-relay node selection scheme is proposed for cooperative transmissions over underlay-paradigm based CR networks,and meanwhile guarantee that the primary link is provided with a minimum-rate for a certain percentage of time.The objective is to increase achievable data rate as well as prolong average network lifetime.Specifically,both the instantaneous channel state information (ICSI) and residual energy of candidate relay nodes are taken as weighted metric,and the relay node with the optimal weighted metric is selected as the best one.Simulation results are presented to demonstrate the effectiveness of the proposed scheme. 展开更多
关键词 cognitive radio (CR) cooperative transmissions relay selection instantaneous channel state information (ICSI) residual energy
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Cross-layer design of combining AMC with HARQ in cooperative relay system with perfect and imperfect CSI
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作者 唐伦 张荣荣 陈前斌 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第4期118-128,共11页
A cross-layer design which combines adaptive modulation and coding (AMC) at the physical layer with a hybrid automatic repeat request (HARQ) protocol at the data link layer (LL) is presented, in cooperative relay syst... A cross-layer design which combines adaptive modulation and coding (AMC) at the physical layer with a hybrid automatic repeat request (HARQ) protocol at the data link layer (LL) is presented, in cooperative relay system over Nakagami-m fading channels with perfect and imperfect channel state information (CSI). In order to maximize spectral efficiency (SE) under delay and packet error rate (PER) performance constraints, a state transition model and an optimization framework with perfect CSI are presented. Then the framework is extended to cooperative relay system with imperfect CSI. The numerical results show that the scheme can achieve maximum SE while satisfying transmitting delay requirements. Compared with the imperfect CSI, the average PER with perfect CSI is much lower and the spectral efficiency is much higher. 展开更多
关键词 cooperative relay system cross-layer design and optimization adaptive modulation and coding (AMC) hybrid automatic REPEAT request (HARQ) PERFECT channel state information(CSI) imperfect CSI
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Online Silk Road Promotes Economic Cooperation Between China and the Arab States
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作者 Audrey Guo 《China's Foreign Trade》 2017年第6期34-35,共2页
According to the 13th Five-year National Informatization Plan issued by the State Council, it is important to establish an online silk road. The "online silk road" is a network- based information economic belt estab... According to the 13th Five-year National Informatization Plan issued by the State Council, it is important to establish an online silk road. The "online silk road" is a network- based information economic belt established by China and countries along the Belt and Road, 展开更多
关键词 Online Silk Road Economic cooperation Between China the Arab states
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China Eyes Closer Environmental Cooperation with Arab States
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作者 Richard Zhu 《China's Foreign Trade》 2015年第5期47-,共1页
China is seeking closer environmental cooperation with Arab States driven by the strategy of 'One Belt and One Road'.'Co-building and greenization of ’One Belt and One Road’ will provide new opportunitie... China is seeking closer environmental cooperation with Arab States driven by the strategy of 'One Belt and One Road'.'Co-building and greenization of ’One Belt and One Road’ will provide new opportunities and contents for China-Arab states cooperation。 展开更多
关键词 BANK CO China Eyes Closer Environmental cooperation with Arab states
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New Industry Guiding Catalog for Foreign Investment Issued by State Development and Planning Commission,State Economic and Trade Commission and Ministry of Foreign Trade and Economic Cooperation
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《China's Foreign Trade》 2002年第4期15-16,共2页
关键词 New Industry Guiding Catalog for Foreign Investment Issued by state Development and Planning Commission state Economic and Trade Commission and Ministry of Foreign Trade and Economic cooperation
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Speech by Mr. Tang Jiaxuan, State Councilor of China, at the Opening Ceremony of the 13th Annual Workshop of the Framework on Regional Cooperation for the Promotion and Protection of Human Rights in the Asia-Pacific Region
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作者 Mr. Tang Jiaxuan, State Councilor of China. 《The Journal of Human Rights》 2005年第6期7-8,共2页
关键词 Speech by Mr state Councilor of China Tang Jiaxuan at the Opening Ceremony of the 13th Annual Workshop of the Framework on Regional cooperation for the Promotion and Protection of Human Rights in the Asia-Pacific Region Asia
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The Origin,Obstacles and Prospects of Sino-US Space Cooperation
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作者 Guo Xiaobing 《Contemporary International Relations》 2018年第6期123-134,共12页
Space is an important part of the Sino-US relationship. It reflects the general direction of bilateral relations, yet has its own development trajectory. As Sino-US relations had their ups and downs in the 1990 s, spa... Space is an important part of the Sino-US relationship. It reflects the general direction of bilateral relations, yet has its own development trajectory. As Sino-US relations had their ups and downs in the 1990 s, space cooperation between the two countries was relatively consistent and stable. But as economy and trade became more and more deeply intertwined in the 21 st century, space cooperation lost its momentum. This paper intends to explore the reasons behind this strange development trajectory by analyzing the security, political, legislative and economic factors affecting bilateral space cooperation. It also tries to analyze the prospect of Sino-US space cooperation in President Trump's term. 展开更多
关键词 China the UNITED stateS SPACE cooperATION SPACE security
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Network coding with diversity and outdated channel state information
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作者 Tong CHEN Kanapathippillai CUMANAN +1 位作者 Zhiguo DING Guiyun TIAN 《Journal of Modern Transportation》 2012年第4期261-267,共7页
Physical-layer network coding (PNC) has the potential to significantly improve the throughput of wireless networks where the channels can be modeled as additive white Gaussian noise (AWGN) channel. As extending to... Physical-layer network coding (PNC) has the potential to significantly improve the throughput of wireless networks where the channels can be modeled as additive white Gaussian noise (AWGN) channel. As extending to mul- tiple channels, this technique requires both amplitude and phase compensation at each transmitter and will lead to inef- ficient systems yielding no diversity even with perfect channel state information (CSI). In order to avoid these limita- tions, we apply network coding with diversity (NCD) to achieve a form of selection diversity and extend NCD to coop- erative multiple access channels in this paper. However, in practical wireless communication systems, the CSI could become outdated due to the difference between the CSI used in the relay selection and data transmission phases. Hence, the selected relay may not be the best one during data transmission phase due to the dynamic change in the wireless channels. Therefore, we first explore the relation between the present and past CSIs. Exploiting this relationship, the NCD scheme with outdated CSI is investigated based on the past CSI. To evaluate the performance of this scheme, an information-theoretic metric, namely the outage capacity, is studied under this condition. 展开更多
关键词 network coding with diversity (NCD) cooperative multiple access channels channel state information (CSI)
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State estimation of connected vehicles using a nonlinear ensemble filter
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作者 刘江 陈华展 +1 位作者 蔡伯根 王剑 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2406-2415,共10页
The concept of connected vehicles is with great potentials for enhancing the road transportation systems in the future. To support the functions and applications under the connected vehicles frame, the estimation of d... The concept of connected vehicles is with great potentials for enhancing the road transportation systems in the future. To support the functions and applications under the connected vehicles frame, the estimation of dynamic states of the vehicles under the cooperative environments is a fundamental issue. By integrating multiple sensors, localization modules in OBUs(on-board units) require effective estimation solutions to cope with various operation conditions. Based on the filtering estimation framework for sensor fusion, an ensemble Kalman filter(En KF) is introduced to estimate the vehicle's state with observations from navigation satellites and neighborhood vehicles, and the original En KF solution is improved by using the cubature transformation to fulfill the requirements of the nonlinearity approximation capability, where the conventional ensemble analysis operation in En KF is modified to enhance the estimation performance without increasing the computational burden significantly. Simulation results from a nonlinear case and the cooperative vehicle localization scenario illustrate the capability of the proposed filter, which is crucial to realize the active safety of connected vehicles in future intelligent transportation. 展开更多
关键词 connected vehicles state estimation cooperative positioning nonlinear ensemble filter global navigation satellite system (GNSS) dedicated short range communication (DSRC)
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Analysis of Economic Cooperation between China, USA, Japan, and ASEAN
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作者 Cheng Xiaoyong Huang Yangzi 《Contemporary International Relations》 2021年第6期110-133,共24页
Since China’s Belt and Road Initiative was introduced,the rapid development of China–ASEAN economic cooperation has aroused suspicion from the United States and Japan,nations that have been cooperating with Southeas... Since China’s Belt and Road Initiative was introduced,the rapid development of China–ASEAN economic cooperation has aroused suspicion from the United States and Japan,nations that have been cooperating with Southeast Asia for a long time.Through comparative analysis,this paper draws a conclusion that the cooperation between China and ASEAN has rapidly grown in trade volume,tourism,infrastructure construction,and other fields,but its advantages in some fields are not yet apparent,and there is no evidence of crowding out the United States and Japan overall.The United States and Japan have been adjusting policies toward ASEAN in a targeted manner,while ASEAN countries do not completely depend on China,establishing a balance in foreign economic cooperation between great powers.Therefore,the economic cooperation between China,the United States,Japan,and ASEAN is experiencing a dynamic adjustment process in long-term competition that is unlikely to lead to exclusive monopoly circumstances. 展开更多
关键词 Belt and Road Initiative China the United states JAPAN ASEAN economic cooperation
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Quantum Entropy of a Cooper-Pair Box in a Single-Mode Cavity Field
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作者 张春雨 邹健 邵彬 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期442-444,共3页
A Cooper-pair box biased by a classical voltage and also irradiated by a squeezed state field is considered in order to find new ways to quantum communication and calculation. The quantum dynamics of the Cooper-pair b... A Cooper-pair box biased by a classical voltage and also irradiated by a squeezed state field is considered in order to find new ways to quantum communication and calculation. The quantum dynamics of the Cooper-pair box and the entanglement which is the core theoretics of quantum communication and calculation is investigated in this system, which is related to the squeezing parameter of the squeezed state, A model of Hamiltonian which represents the interaction between box and quantum field is introduced. Finally, the relationship between the entanglement and the squeezing parameter of the squeezed state is demonstrated. 展开更多
关键词 quantum entropy ENTANGLEMENT squeezed state cooper-pair box
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Cooper-pair number-phase quantization analysis in double-Josephson-junction mesoscopic circuit coupled by a capacitor
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作者 梁宝龙 王继锁 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期697-701,共5页
This paper examines the quantization of mesoscopic circuit including Josephson junctions. Following Feynman's assumption, via the Hamilton dynamic approach and by virtue of the entangled state representation, it cons... This paper examines the quantization of mesoscopic circuit including Josephson junctions. Following Feynman's assumption, via the Hamilton dynamic approach and by virtue of the entangled state representation, it constructs Hamiltonian operator for the double-Josephson-junction mesoscopic circuit coupled by a capacitor. Then it uses the Heisenberg equation of motion to derive the induction voltage across each Josephson junction. The result manifestly shows how the voltage is affected by the capacitance coupling. 展开更多
关键词 JOSEPHSON-JUNCTION cooper-pair entangled state representation phase squeezing
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基于深度强化学习的SCR脱硝系统协同控制策略研究 被引量:3
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作者 赵征 刘子涵 《动力工程学报》 CAS CSCD 北大核心 2024年第5期802-809,共8页
针对选择性催化还原(SCR)脱硝系统大惯性、多扰动等特点,提出了一种基于多维状态信息和分段奖励函数优化的深度确定性策略梯度(DDPG)协同比例积分微分(PID)控制器的控制策略。针对SCR脱硝系统中存在部分可观测马尔可夫决策过程(POMDP),... 针对选择性催化还原(SCR)脱硝系统大惯性、多扰动等特点,提出了一种基于多维状态信息和分段奖励函数优化的深度确定性策略梯度(DDPG)协同比例积分微分(PID)控制器的控制策略。针对SCR脱硝系统中存在部分可观测马尔可夫决策过程(POMDP),导致DDPG算法策略学习效率较低的问题,首先设计SCR脱硝系统的多维状态信息;其次,设计SCR脱硝系统的分段奖励函数;最后,设计DDPG-PID协同控制策略,以实现SCR脱硝系统的控制。结果表明:所设计的DDPG-PID协同控制策略提高了DDPG算法的策略学习效率,改善了PID的控制效果,同时具有较强的设定值跟踪能力、抗干扰能力和鲁棒性。 展开更多
关键词 DDPG 强化学习 SCR脱硝系统 协同控制 多维状态 分段奖励函数
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美国全球水资源安全战略分析 被引量:2
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作者 任娜 《亚太安全与海洋研究》 CSSCI 北大核心 2024年第2期72-88,I0003,I0004,共19页
由于相对实力下降,美国的霸权正面临“碎片化”与“议题化”转型。在众多涉及安全的议题中,水资源议题因为自身的敏感性,成为美国国家安全的重要组成部分。2022年美国相继发布《全球水安全行动计划》和第二个《美国全球水战略》文件,明... 由于相对实力下降,美国的霸权正面临“碎片化”与“议题化”转型。在众多涉及安全的议题中,水资源议题因为自身的敏感性,成为美国国家安全的重要组成部分。2022年美国相继发布《全球水安全行动计划》和第二个《美国全球水战略》文件,明确了未来一段时期美国在全球水资源领域的战略目标、原则、优先方向、实施路径以及项目规划。其在优先方向、重点地区以及实施路径等方面的新变化,不但会对中美在水资源领域的竞争产生重要影响,更可能干扰中国与周边国家在水资源领域的合作。中国需加强跟踪研判和科学谋划,不断调整和优化与周边国家开展水资源合作及治理的政策和路径,化解美国对华开展水资源竞争所带来的风险。 展开更多
关键词 美国 水资源 水资源合作 中美博弈 安全战略 国家安全
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