本文通过对维持体系运行条件的确定、体系运行效果的确认与验证、体系运行证据的收集留存及预防性控制等的研究阐明了基于ISO/FD IS 22000标准的饲料安全管理体系的实施、保持、持续改进和更新的具体要求和措施方法,为饲料生产企业ISO/F...本文通过对维持体系运行条件的确定、体系运行效果的确认与验证、体系运行证据的收集留存及预防性控制等的研究阐明了基于ISO/FD IS 22000标准的饲料安全管理体系的实施、保持、持续改进和更新的具体要求和措施方法,为饲料生产企业ISO/FD IS 22000饲料安全管理体系的实施、保持、改进和更新提供指南.展开更多
针对园区级源网荷储一体化配电网(以下简称有源配电网)电压弹性协调控制问题,提出了一种电压弹性协调控制方法,实现了对有源配电网的电压有效调节并维持P/Q控制模式下各分布式发电恒定功率。对虚假数据注入(false data injection,FDI)...针对园区级源网荷储一体化配电网(以下简称有源配电网)电压弹性协调控制问题,提出了一种电压弹性协调控制方法,实现了对有源配电网的电压有效调节并维持P/Q控制模式下各分布式发电恒定功率。对虚假数据注入(false data injection,FDI)攻击下对园区内部的分布式能源、电网、储能和柔性负荷模型进行分析,建立了源网荷储互动特性下的源网荷储一体化配电网模型,在电压协调侧设计状态观测器与攻击估计器,并基于李雅普诺夫稳定性理论证明其收敛性,接下来,基于上述状态观测器与攻击估计器,提出了一种智能互动的弹性控制策略,实现对攻击影响的补偿,保证有源配电网的安全运行,并进行了有效性验证,在MATLAB/Simulink中搭建仿真,验证了所提出协调控制策略的有效性。展开更多
An attack-resilient distributed Nash equilibrium(NE) seeking problem is addressed for noncooperative games of networked systems under malicious cyber-attacks,i.e.,false data injection(FDI) attacks.Different from many ...An attack-resilient distributed Nash equilibrium(NE) seeking problem is addressed for noncooperative games of networked systems under malicious cyber-attacks,i.e.,false data injection(FDI) attacks.Different from many existing distributed NE seeking works,it is practical and challenging to get resilient adaptively distributed NE seeking under unknown and unbounded FDI attacks.An attack-resilient NE seeking algorithm that is distributed(i.e.,independent of global information on the graph's algebraic connectivity,Lipschitz and monotone constants of pseudo-gradients,or number of players),is presented by means of incorporating the consensus-based gradient play with a distributed attack identifier so as to achieve simultaneous NE seeking and attack identification asymptotically.Another key characteristic is that FDI attacks are allowed to be unknown and unbounded.By exploiting nonsmooth analysis and stability theory,the global asymptotic convergence of the developed algorithm to the NE is ensured.Moreover,we extend this design to further consider the attack-resilient NE seeking of double-integrator players.Lastly,numerical simulation and practical experiment results are presented to validate the developed algorithms' effectiveness.展开更多
在全球产业链重构和双循环新发展格局背景下,双向FDI(Foreign Direct Investment)如何助力我国产业结构升级成为关注焦点。本文基于2010—2023年省际面板数据,构建回归模型和门槛模型,实证检验了双向FDI协调发展对产业结构合理化与高度...在全球产业链重构和双循环新发展格局背景下,双向FDI(Foreign Direct Investment)如何助力我国产业结构升级成为关注焦点。本文基于2010—2023年省际面板数据,构建回归模型和门槛模型,实证检验了双向FDI协调发展对产业结构合理化与高度化的异质动态影响。结果显示,双向FDI协调发展显著推动了我国产业结构升级,对产业结构合理化具有稳定的正向影响,对产业结构高度化存在双重门槛效应,呈现“低效—提效—高效”的演化特征。展开更多
For direct sequence spread spectrum （DSSS） receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression （FDIS）. The key is...For direct sequence spread spectrum （DSSS） receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression （FDIS）. The key issue of this process is how to determine a threshold to eliminate interference in the frequency domain, which has been extensively studied. However, these previous methods are tedious or very complex. A simple and ef- ficient algorithm based on medians is proposed. The elimination threshold is only related to the median by a scale factor, which can be obtained by the numerical analysis. Simulation results show that the algorithm provides excellent narrow-band interfer- ence suppression while only slightly degrading the signal-to-noise ratio （SNR）. A one-pass algorithm using logarithmic segmentation is further derived to estimate medians with low computational complexity. Finally, the FDIS is implemented in a field programmable gate array （FPGA） of Xilinx. Experiments are carried out by connecting the FDIS FPGA to a DSSS receiver, and the results show that the receiver has an effective countermeasure for a 60 dB interference-to-signal ratio （ISR）.展开更多
文摘本文通过对维持体系运行条件的确定、体系运行效果的确认与验证、体系运行证据的收集留存及预防性控制等的研究阐明了基于ISO/FD IS 22000标准的饲料安全管理体系的实施、保持、持续改进和更新的具体要求和措施方法,为饲料生产企业ISO/FD IS 22000饲料安全管理体系的实施、保持、改进和更新提供指南.
文摘针对园区级源网荷储一体化配电网(以下简称有源配电网)电压弹性协调控制问题,提出了一种电压弹性协调控制方法,实现了对有源配电网的电压有效调节并维持P/Q控制模式下各分布式发电恒定功率。对虚假数据注入(false data injection,FDI)攻击下对园区内部的分布式能源、电网、储能和柔性负荷模型进行分析,建立了源网荷储互动特性下的源网荷储一体化配电网模型,在电压协调侧设计状态观测器与攻击估计器,并基于李雅普诺夫稳定性理论证明其收敛性,接下来,基于上述状态观测器与攻击估计器,提出了一种智能互动的弹性控制策略,实现对攻击影响的补偿,保证有源配电网的安全运行,并进行了有效性验证,在MATLAB/Simulink中搭建仿真,验证了所提出协调控制策略的有效性。
基金supported in part by the National Natural Science Foundation of China(62373022,U2241217,62141604)Beijing Natural Science Foundation(4252043,JQ23019)+4 种基金the Fundamental Research Funds for the Central Universities(JKF-2025037448805,JKF-2025086098295)the Aeronautical Science Fund(2023Z034051001)the Academic Excellence Foundation of BUAA for Ph.D. Studentsthe Science and Technology Innovation2030—Key Project of New Generation Artificial Intelligence(2020AAA0108200)the National Key Research and Development Program of China(2022YFB3305600)。
文摘An attack-resilient distributed Nash equilibrium(NE) seeking problem is addressed for noncooperative games of networked systems under malicious cyber-attacks,i.e.,false data injection(FDI) attacks.Different from many existing distributed NE seeking works,it is practical and challenging to get resilient adaptively distributed NE seeking under unknown and unbounded FDI attacks.An attack-resilient NE seeking algorithm that is distributed(i.e.,independent of global information on the graph's algebraic connectivity,Lipschitz and monotone constants of pseudo-gradients,or number of players),is presented by means of incorporating the consensus-based gradient play with a distributed attack identifier so as to achieve simultaneous NE seeking and attack identification asymptotically.Another key characteristic is that FDI attacks are allowed to be unknown and unbounded.By exploiting nonsmooth analysis and stability theory,the global asymptotic convergence of the developed algorithm to the NE is ensured.Moreover,we extend this design to further consider the attack-resilient NE seeking of double-integrator players.Lastly,numerical simulation and practical experiment results are presented to validate the developed algorithms' effectiveness.
文摘在全球产业链重构和双循环新发展格局背景下,双向FDI(Foreign Direct Investment)如何助力我国产业结构升级成为关注焦点。本文基于2010—2023年省际面板数据,构建回归模型和门槛模型,实证检验了双向FDI协调发展对产业结构合理化与高度化的异质动态影响。结果显示,双向FDI协调发展显著推动了我国产业结构升级,对产业结构合理化具有稳定的正向影响,对产业结构高度化存在双重门槛效应,呈现“低效—提效—高效”的演化特征。
基金supported by the National Natural Science Foundation of China(60904090)
文摘For direct sequence spread spectrum （DSSS） receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression （FDIS）. The key issue of this process is how to determine a threshold to eliminate interference in the frequency domain, which has been extensively studied. However, these previous methods are tedious or very complex. A simple and ef- ficient algorithm based on medians is proposed. The elimination threshold is only related to the median by a scale factor, which can be obtained by the numerical analysis. Simulation results show that the algorithm provides excellent narrow-band interfer- ence suppression while only slightly degrading the signal-to-noise ratio （SNR）. A one-pass algorithm using logarithmic segmentation is further derived to estimate medians with low computational complexity. Finally, the FDIS is implemented in a field programmable gate array （FPGA） of Xilinx. Experiments are carried out by connecting the FDIS FPGA to a DSSS receiver, and the results show that the receiver has an effective countermeasure for a 60 dB interference-to-signal ratio （ISR）.
