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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:4
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作者 Ding Wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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Improved Disturbance Observer (DOB) Based Advanced Feedback Control for Optimal Operation of a Mineral Grinding Process 被引量:4
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作者 周平 向波 柴天佑 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1206-1212,共7页
Advanced feedback control for optimal operation of mineral grinding process is usually based on the model predictive control (MPC) dynamic optimization. Since the MPC does not handle disturbances directly by controlle... Advanced feedback control for optimal operation of mineral grinding process is usually based on the model predictive control (MPC) dynamic optimization. Since the MPC does not handle disturbances directly by controller design, it cannot achieve satisfactory effects in controlling complex grinding processes in the presence of strong disturbances and large uncertainties. In this paper, an improved disturbance observer (DOB) based MPC advanced feedback control is proposed to control the multivariable grinding operation. The improved DOB is based on the optimal achievable H 2 performance and can deal with disturbance observation for the nonminimum-phase delay systems. In this DOB-MPC advanced feedback control, the higher-level optimizer computes the optimal operation points by maximize the profit function and passes them to the MPC level. The MPC acts as a presetting controller and is employed to generate proper pre-setpoint for the lower-level basic feedback control system. The DOB acts as a compensator and improves the operation performance by dynamically compensating the setpoints for the basic control system according to the observed various disturbances and plant uncertainties. Several simulations are performed to demonstrate the proposed control method for grinding process operation. 展开更多
关键词 disturbance observer model predictive control advanced feedback control grinding process steady-state optimization disturbance rejection
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Design and Application of Third-order Denitration Online Control Technology 被引量:2
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作者 Wang Li Wang Yanjin Kang Jingqiu 《Meteorological and Environmental Research》 CAS 2019年第4期93-96,共4页
In order to alleviate the pressure of environmental protection and further strengthen the monitoring and control of NOx emission of thermal power units, combining with the transformation of boiler low-nitrogen burner,... In order to alleviate the pressure of environmental protection and further strengthen the monitoring and control of NOx emission of thermal power units, combining with the transformation of boiler low-nitrogen burner, combustion optimization, static and dynamic ratio of air and coal, and SCR denitration system process, third-order NOx online control technology was designed and applied, which takes the combustion security, boiler efficiency and environmental evaluation into account and provide reference for thermal power units to deepen energy conservation and emission reduction. 展开更多
关键词 NOx control TECHNOLOGY COMBUSTION optimization Environmental assessment Energy CONSERVATION and EMISSION reduction
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TECHNIQUES ABOUT DIRECT OPTIMIZING CONTROL OF GREEN SAND QUALITY
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作者 Li Dayong Xu Xiongfei Ma Xuliang Zhang Yutong School of Material Science and Engineering,Harbin University of Science and Technology, Harbin 150080,China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第1期83-86,93,共5页
Green sand casting is still a main method in the world at present and it isvery significant to develop the technology of controlling green sand quality. A new concept, fromcontents test to contents control, is advance... Green sand casting is still a main method in the world at present and it isvery significant to develop the technology of controlling green sand quality. A new concept, fromcontents test to contents control, is advanced. In order to realize the new idea, a new method toon-line test active clay and moisture of green sand - double powers energizing alternately (DPEA)method is put forwards. The principle of the new method is to energize standard sand sample with ACand DC powers and to test the electric parameters, and then, to calculate active clay and moistureof green sand by using artificial neural network (ANN). Based on this new method, a directoptimizing system for controlling green sand quality is developed. Techniques about testing andcontrolling methods, hardware and software are discussed. 展开更多
关键词 New technology Green sand quality Optimizing control
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STRATEGY AND IMPLEMENTATION FOR HIGH-SPEED TORQUE ENHANCEMENT OF BRUSHLESS DC MOTOR 被引量:1
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作者 韦榕 许镇琳 蔡昆 《Transactions of Tianjin University》 EI CAS 2001年第2期76-80,共5页
Serious commutation lag occurs when a Brushless DC Motor(BLDCM) operates at high speeds,and this leads to torque decline with ripple.In this paper,an advanced conduction control scheme is proposed which can accelerate... Serious commutation lag occurs when a Brushless DC Motor(BLDCM) operates at high speeds,and this leads to torque decline with ripple.In this paper,an advanced conduction control scheme is proposed which can accelerate the commutation and enhance the torque production remarkably.Besides,an on line adjusting algorithm based on the Golden Section Method is adopted to search the optimal advanced conduction angle.Simulation and experimental results verify the feasibility and effectivity of the scheme proposed. 展开更多
关键词 BLDCM high speed torque optimal advanced conduction angle control
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Optimized model-based control of main mine ventilation air flows with minimized energy consumption 被引量:5
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作者 S.Sjostrom E.Klintenas +1 位作者 P.Johansson J.Nyqvist 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第4期533-539,共7页
In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for ma... In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for main and booster fans,whilst also fulfilling airflow setpoints without violating constraints such as min/max differential pressure over fans and interaction of air between areas in mines.Using air flow measurements and a dynamical model of the ventilation system,a mine-wide coordination control of fans can be carried out.The numerical model is data driven and derived from historical operational data or step changes experiments.This makes both initial deployment and lifetime model maintenance,as the mine evolves,a comparably easy operation.The control has been proven to operate in a stable manner over long periods without having to re-calibrate the model.Results prove a 40%decrease in energy use for the fans involved and a greater controllability of air flow.Moreover,a 15%decrease of the total air flow into the mine will give additional proportional heating savings during winter periods.All in all,the multivariable controller shows a correlation between production in the mine and the ventilation system performance superior to all of its predecessors. 展开更多
关键词 Mine ventilation Ventilation on demand Optimized model-based control Minimized energy consumption advanced process control
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Computing Open-Loop Optimal Control of the q-Profile in Ramp-Up Tokamak Plasmas Using the Minimal-Surface Theory
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作者 许超 欧勇盛 +1 位作者 Eugenio SCHUSTER 于欣 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第5期403-410,共8页
The q-profile control problem in the ramp-up phase of plasma discharges is consid- ered in this work. The magnetic diffusion partial differential equation (PDE) models the dynamics of the poloidal magnetic flux prof... The q-profile control problem in the ramp-up phase of plasma discharges is consid- ered in this work. The magnetic diffusion partial differential equation (PDE) models the dynamics of the poloidal magnetic flux profile, which is used in this work to formulate a PDE-constrained op-timization problem under a quasi-static assumption. The minimum surface theory and constrained numeric optimization are then applied to achieve suboptimal solutions. Since the transient dy- namics is pre-given by the minimum surface theory, then this method can dramatically accelerate the solution process. In order to be robust under external uncertainties in real implementations, PID (proportional-integral-derivative) controllers are used to force the actuators to follow the computational input trajectories. It has the potential to implement in real-time for long time discharges by combining this method with the magnetic equilibrium update. 展开更多
关键词 advanced plasma operations current profile dynamics optimal control theory minimal surface equation differential geometry
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An overview of the operation architectures and energy management system for multiple microgrid clusters 被引量:1
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作者 Yajuan Guan Baoze Wei +2 位作者 Josep M.Guerrero Juan C.Vasquez Yonghao Gui 《iEnergy》 2022年第3期306-314,共9页
The emerging novel energy infrastructures,such as energy communities,smart building-based microgrids,electric vehicles enabled mobile energy storage units raise the requirements for a more interconnective and interope... The emerging novel energy infrastructures,such as energy communities,smart building-based microgrids,electric vehicles enabled mobile energy storage units raise the requirements for a more interconnective and interoperable energy system.It leads to a transition from simple and isolated microgrids to relatively large-scale and complex interconnected microgrid systems named multi-microgrid clusters.In order to efficiently,optimally,and flexibly control multi-microgrid clusters,cross-disciplinary technologies such as power electronics,control theory,optimization algorithms,information and communication technologies,cyber-physical,and big-data analysis are needed.This paper introduces an overview of the relevant aspects for multi-microgrids,including the out-standing features,architectures,typical applications,existing control mechanisms,as well as the challenges. 展开更多
关键词 Renewable energy resource multi-microgrid cluster power electronics control theory optimization algorithms information and communication technologies big-data analysis.
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Optimal Gliding Guidance of Vertical Plane for Standoff Released Guided Bomb Unit
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作者 侯明善 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第1期48-51,共4页
Optimal gliding guidance for a guided bomb unit in the vertical plane is studied based on nonlinear dynamics and kinematics.The guidance law is designed under minimum energy loss index.To avoid the complexity in solvi... Optimal gliding guidance for a guided bomb unit in the vertical plane is studied based on nonlinear dynamics and kinematics.The guidance law is designed under minimum energy loss index.To avoid the complexity in solving two-point-boundary-value problems,the steady-state solutions of the adjoint states in regular equations are suggested to be used.With these considerations,a quasi-closed,optimal gliding guidance law is obtained.The guidance law is described by the angle of attack in a simple nonlinear equation.An iterative computation method can be easily used to get the optimal angle of attack.The further simplified direct computation algorithm for the optimal angle of attack is also given.The guidance properties are compared with those of maximum lift-to-drag angle of attack control.The simulation results demonstrate that the quasi-closed,optimal gliding guidance law can improve the gliding phase terminal performance with significant increase in the altitude and much little decrease in the speed. 展开更多
关键词 飞行器 控制导航技术 导弹引导系统 最佳导航系统 最佳控制系统
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Re-entry Attitude Double-loop SMC of the Spacecraft and Its Logic Selection
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作者 陈玉文 毕开波 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第3期195-198,共4页
A spacecraft re-entry attitude control method using sliding mode control (SMC) theory is developed. The controller utilizes double-loop SMC scheme and provides the robust, de-coupled tracking of both the angular veloc... A spacecraft re-entry attitude control method using sliding mode control (SMC) theory is developed. The controller utilizes double-loop SMC scheme and provides the robust, de-coupled tracking of both the angular velocity and the shuttle orientation angles. In accordance with the hybrid-controlling characteristics of the aerodynamic surfaces and reaction control system of the spacecraft, the control torque commands are allocated into the actuators such as the aerodynamic surfaces and reaction control system by using the optimal control selection allocation algorithm. The simulation of the spacecraft re-entry attitude controlling demonstrates the robust, de-coupled tracking performance of the proposed method and its validity. 展开更多
关键词 控制导航系统 飞行器 遥感器 飞行模式控制
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Temperature-Based Fan Speed Optimization Strategy
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作者 Chucheng Wang Chongyi Luo +3 位作者 Junnian Wei Haiyang Peng Xiaorong Zhong Cai Ye 《Journal of Electronic Research and Application》 2024年第3期135-141,共7页
As energy efficiency and indoor comfort increasingly become key standards in modern residential and office environments,research on intelligent fan speed control systems has become particularly important.This study ai... As energy efficiency and indoor comfort increasingly become key standards in modern residential and office environments,research on intelligent fan speed control systems has become particularly important.This study aims to develop a temperature-feedback-based fan speed optimization strategy to achieve higher energy efficiency and user comfort.Firstly,by analyzing existing fan speed control technologies,their main limitations are identified,such as the inability to achieve smooth speed transitions.To address this issue,a BP-PID speed control algorithm is designed,which dynamically adjusts fan speed based on indoor temperature changes.Experimental validation demonstrates that the designed system can achieve smooth speed transitions compared to traditional fan systems while maintaining stable indoor temperatures.Furthermore,the real-time responsiveness of the system is crucial for enhancing user comfort.Our research not only demonstrates the feasibility of temperature-based fan speed optimization strategies in both theory and practice but also provides valuable insights for energy management in future smart home environments.Ultimately,this research outcome will facilitate the development of smart home systems and have a positive impact on environmental sustainability. 展开更多
关键词 Smart temperature control Fan speed optimization Temperature feedback control Dynamic speed adjustment Smart home systems Energy-saving technology
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Discussion on the Construction of Anti-smoke Construction Technology in Super High-rise Buildings
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作者 Xiaolong Ruan 《Journal of World Architecture》 2019年第4期1-4,共4页
In recent years with the increasing number of super high-rise buildings and the ever-expanding scale the anti-smoke construction technology has attracted more and more attention.Based on this situation,this paper anal... In recent years with the increasing number of super high-rise buildings and the ever-expanding scale the anti-smoke construction technology has attracted more and more attention.Based on this situation,this paper analyzes the smoke control technology of super high-rise buildings.The paper analyzes the importance of the application of anti-smoke construction technology in super high-rise buildings,analyzes the problems in the construction of smoke control and super high-rise buildings.The anti-smoke construction technology was studied and I hope that it can benefit the application of anti-smoke construction technology in high-rise buildings. 展开更多
关键词 Super HIGH-RISE BUILDING SMOKE control CONSTRUCTION technology Problem and optimization
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京津冀科技创新投入对产业结构高级化的影响 被引量:2
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作者 吴丹 潘朱玲 《科技和产业》 2024年第1期1-9,共9页
京津冀科技创新对于推动京津冀地区产业结构高级化提供了有力支撑。通过明确京津冀科技创新投入对产业结构高级化影响的被解释变量、解释变量和控制变量,确定京津冀科技创新投入对产业结构高级化影响的指标。构建京津冀科技创新投入对... 京津冀科技创新对于推动京津冀地区产业结构高级化提供了有力支撑。通过明确京津冀科技创新投入对产业结构高级化影响的被解释变量、解释变量和控制变量,确定京津冀科技创新投入对产业结构高级化影响的指标。构建京津冀科技创新投入对产业结构高级化影响的静态回归模型和动态回归模型,利用2009—2020年面板数据,深入开展京津冀地区科技创新投入对产业结构高级化影响的对比研究。结果表明:京津冀整体的科技创新投入对其产业结构高级化的影响显著,科技创新投入增加能显著促进产业结构高级化;京津冀科技创新投入对产业结构高级化的影响程度存在显著的空间差异,经济发展水平显著影响地区科技创新投入对产业结构高级化的促进力度;考虑控制变量,区域对外开放水平显著抑制地区产业结构高级化,人力资本水平与政府支持力度对地区产业结构高级化影响存在显著空间差异。根据研究结果,提出京津冀科技创新推动产业结构高级化的对策建议。 展开更多
关键词 京津冀 科技创新 产业结构高级化 影响效应 控制变量 静态回归模型 动态回归模型
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球形电动机及其研究发展综述
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作者 赵静 何威 +3 位作者 刘向东 李伟力 李争 杨磊 《中国电机工程学报》 EI CSCD 北大核心 2024年第2期737-754,I0026,共19页
球形电动机是一种具有球体结构的新型电动机,可单机实现在三维空间内的多自由度运动,且适合应用于人工智能及姿态控制系统动量球等相关领域,得到了各国学者的广泛关注与研究。球形电动机拓展了转子运动范围,是电动机行业未来的一个重要... 球形电动机是一种具有球体结构的新型电动机,可单机实现在三维空间内的多自由度运动,且适合应用于人工智能及姿态控制系统动量球等相关领域,得到了各国学者的广泛关注与研究。球形电动机拓展了转子运动范围,是电动机行业未来的一个重要发展方向。与传统单自由度电动机相比,球形电动机结构较为复杂,且运动模式较为特殊,因此,对球形电动机的分析研究有别于传统单自由度电动机。该文整理各国学者对球形电动机的研究工作,总结归纳球形电动机的概念及发展历程,对比研究球形电动机不同的工作原理、拓扑结构及设计优化方法,探讨球形电动机的性能、转子位置检测方法、控制方法、转子支撑方式、应用场合及关键技术,最后总结球形电动机的未来发展趋势。 展开更多
关键词 球形电动机 多自由度运动 拓扑结构 设计优化方法 控制技术
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托顶煤巷道易片冒顶板变形机理与超前导管预注浆控制技术研究
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作者 陈晓祥 韩文宇 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第4期1-11,共11页
目的 为探究厚煤层易片冒区域托顶煤巷道顶板变形破坏机理,并对易片冒区托顶煤巷道顶板进行有效控制,方法 以常村煤矿2701工作面皮带运输巷为例,通过等截面梁理论分析托顶煤巷道顶板破断成因,研究托顶煤巷道顶板的稳定性与巷道宽度和顶... 目的 为探究厚煤层易片冒区域托顶煤巷道顶板变形破坏机理,并对易片冒区托顶煤巷道顶板进行有效控制,方法 以常村煤矿2701工作面皮带运输巷为例,通过等截面梁理论分析托顶煤巷道顶板破断成因,研究托顶煤巷道顶板的稳定性与巷道宽度和顶煤强度的关系。通过极限平衡准则得到巷帮位移的计算公式,证明托顶煤巷道具有帮顶协同变形机制。建立托顶煤巷道数值模型,研究巷道埋深、侧压系数、顶煤厚度和顶煤强度与托顶煤巷道围岩稳定性的关系。结果 结果表明:巷道埋深越大,其对托顶煤巷道两帮稳定性的影响越大;侧压系数的增加对巷道两帮和底鼓量的影响更大,对顶板影响较小;顶板下沉量与顶煤厚度呈正相关,底鼓量则与顶煤厚度呈负相关;顶煤强度的增加使巷道顶板下沉量与两帮移近量均近似呈线性减小趋势,底鼓量基本保持不变。结论 通过幂律型流体柱形渗透注浆扩散理论得到超前导管注浆半径,由此提出托顶煤巷道超前导管预注浆帮顶联合控制技术,成功控制易片冒托顶煤巷道顶板冒落问题,可为类似地质条件的托顶煤巷道顶板控制提供借鉴。 展开更多
关键词 厚煤层 托顶煤巷道 顶板破断机理 超前导管 注浆 帮顶联合控制技术
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4DI110型空压机的技术改造与操作优化
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作者 李强 《化工管理》 2024年第14期122-125,共4页
文章通过介绍新引进的4DI110型离心式空压机(以下简称“空压机”)试运行阶段开始以来的运行情况和气温变化对空压机出口流量造成的影响,分析空压机出口流量随气温变化而变化的规律,指出空压机防喘阀V3004阀不能自动调节出口压力,影响空... 文章通过介绍新引进的4DI110型离心式空压机(以下简称“空压机”)试运行阶段开始以来的运行情况和气温变化对空压机出口流量造成的影响,分析空压机出口流量随气温变化而变化的规律,指出空压机防喘阀V3004阀不能自动调节出口压力,影响空分装置工况的稳定。为实现空压机出口压力的稳定,对其防喘阀V3004阀采取增设自动旁路阀V3008阀的技术改造,同时优化和完善相关逻辑控制并阐述了空压机经技术改造后的操作优化和取得的实际效果。 展开更多
关键词 4DI110型离心式空压机 逻辑控制 技术改造 操作优化
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拜登政府对华出口管制主题态势解析及应对策略 被引量:2
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作者 张潇 苏楠 +1 位作者 陈志 王治喃 《中国科技论坛》 CSSCI 北大核心 2024年第1期168-177,共10页
2022年10月,拜登政府发布任内第一份《国家安全战略》报告,明确以应对中国挑战为目标,使用“综合威慑法”得以从战略上“竞赢”美国的地缘经济和政治竞争对手——中国,出口管制是美国政府实现这一目标至关重要的撒手锏。本文采用2021—2... 2022年10月,拜登政府发布任内第一份《国家安全战略》报告,明确以应对中国挑战为目标,使用“综合威慑法”得以从战略上“竞赢”美国的地缘经济和政治竞争对手——中国,出口管制是美国政府实现这一目标至关重要的撒手锏。本文采用2021—2022年拜登政府的官方文件等开源资料,运用社会网络和文本聚类的分析方法,系统解析拜登总统任内对华出口管制的焦点主题。研究表明:“科技”“军事”“供应链”“新疆”是拜登政府对华出口管制的关注重点,且热度交替演进。拜登政府基本延续了特朗普时期的出口管制政策,并在此基础上重视出口管制与其他制裁工具间的联动,进一步强化联合其他国家构筑“去中化”的高技术联盟。 展开更多
关键词 拜登政府 出口管制 技术联盟 高技术
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作物根结线虫病化学防治研究进展 被引量:3
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作者 刘阳 李长洋 +3 位作者 姚志浩 张腾 慕卫 刘峰 《农药学学报》 CAS CSCD 北大核心 2024年第1期8-22,共15页
根结线虫Meloidogyne spp.是严重威胁农业生产的重要病原生物,对世界上大多数作物都存在负面影响。在我国,随着保护地栽培模式的扩大及作物复种指数的不断提高,根结线虫病的发生日趋严重,而目前的管理措施尚不能完全控制根结线虫的危害... 根结线虫Meloidogyne spp.是严重威胁农业生产的重要病原生物,对世界上大多数作物都存在负面影响。在我国,随着保护地栽培模式的扩大及作物复种指数的不断提高,根结线虫病的发生日趋严重,而目前的管理措施尚不能完全控制根结线虫的危害。使用化学杀线虫剂仍然是目前防治根结线虫最常见的短期管理策略。本文总结了目前我国作物根结线虫病的发生现状,介绍了生产中防治该病害的主要化学药剂,分析了其化学防治存在的主要问题,并讨论了目前化学杀线虫剂及其应用技术的优化;展望了未来根结线虫化学防治的研究方向;提出根结线虫的化学防治应该与其他管理措施相结合,实现根结线虫高效、安全、可持续发展的综合治理。 展开更多
关键词 根结线虫 化学防治 杀线虫剂 农药剂型 施药技术 研究进展
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进口大豆绿色控温储藏技术优化研究
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作者 杨晓鑫 《粮食加工》 2024年第5期92-93,96,共3页
进口大豆是我国油脂行业宏观调控、保证食用油脂市场供给的重要手段之一,保证进口大豆储备安全至关重要。针对进口大豆的含油率高、杂质大、水分高不易保管的物理特性,通过对进口储备大豆控温储存工艺技术的研究,阐述了影响进口大豆安... 进口大豆是我国油脂行业宏观调控、保证食用油脂市场供给的重要手段之一,保证进口大豆储备安全至关重要。针对进口大豆的含油率高、杂质大、水分高不易保管的物理特性,通过对进口储备大豆控温储存工艺技术的研究,阐述了影响进口大豆安全储藏的关键要素,优化了进口大豆安全储藏技术措施,提出了适合辽宁地区气候特点的进口大豆绿色控温储藏工艺技术,对有效提升进口大豆的安全储存技术水平,减少进口大豆储藏损失,避免化学药剂熏蒸,保障进口大豆储藏安全等方面具有重要意义。 展开更多
关键词 进口大豆 控温储藏 技术优化
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软岩隧道NPR锚索主动控制关键技术 被引量:2
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作者 钟华 韩玉 +1 位作者 陶志刚 刘能源 《地下空间与工程学报》 CSCD 北大核心 2024年第2期587-596,605,共11页
为解决横断山区软岩隧道的大变形问题,本文以云南省昌宁至保山高速公路昌宁隧道为工程背景,采用理论分析、现场试验等方法,从作用机理、支护方案、施工工艺等方面对软岩隧道开展了高预紧力恒阻大变形(NPR)锚索主动支护及关键技术研究。... 为解决横断山区软岩隧道的大变形问题,本文以云南省昌宁至保山高速公路昌宁隧道为工程背景,采用理论分析、现场试验等方法,从作用机理、支护方案、施工工艺等方面对软岩隧道开展了高预紧力恒阻大变形(NPR)锚索主动支护及关键技术研究。结果表明:被动支护下,隧道围岩节理裂隙发育、黏土矿物含量高、围岩强度低、微观结构存在细小溶蚀孔、结构疏松等是昌宁隧道围岩发生变形破坏的主因;提出了“NPR锚索+PR锚索+“W”钢带+高强柔性网”主动支护技术,并通过现场松动圈测试等试验,确定了NPR锚索、PR锚索等的支护参数;针对极破碎围岩及含水软岩的特殊环境,提出了“先喷后支+复喷”和“锚固端下缘封堵+钢绞线端头加丝”NPR锚索主动支护优化技术;现场试验结果表明,NPR锚索主动控制技术能够有效控制软岩隧道围岩大变形,最大变形量由原来的2125 mm控制到300 mm以内,保障了隧道支护结构的安全。 展开更多
关键词 软岩隧道 主动控制 NPR锚索 支护技术 优化技术
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