5G基站、分布式光伏(distributed photovoltaic,DPV)等分布式资源大规模参与配电网经济与电能质量等多目标优化调度,致使配电网调控模型决策变量复杂、求解时间慢等问题凸显。为此,提出一种考虑5G基站调控潜力和多资源协同的配电网分层...5G基站、分布式光伏(distributed photovoltaic,DPV)等分布式资源大规模参与配电网经济与电能质量等多目标优化调度,致使配电网调控模型决策变量复杂、求解时间慢等问题凸显。为此,提出一种考虑5G基站调控潜力和多资源协同的配电网分层分区优化方法。首先,考虑5G基站通信流量波动特性,建立计及闲置荷电状态(state of charge,SOC)约束的5G基站调控潜力模型。基于此,再建立配电网分层分区优化模型。上层以配电网综合效益最优为目标进行集中式调度,从而确定配电网分组投切电容器组、静止无功发生器等自身资源的动作方案。下层为分区调度,结合电压-功率灵敏度和考虑5G基站通信负荷的源荷不匹配度指标进行配电网物理分区,建立面向5G基站闲置SOC和DPV剩余容量的配电网分区协调优化模型,并采用二阶锥规划和同步型交替方向乘子法相结合的混合算法进行求解。最后,以改进的IEEE33节点配电网为算例,分析验证了所提方法的有效性。结果表明,所提方法能够提高配电网调控模型的求解能力,并提升配电网经济性和电压质量。展开更多
Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military...Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military images.The proposed encryption method is based on multilevel security stages of pixel-level scrambling,bitlevel manipulation,and block-level shuffling operations.For having a vast key space,the input password is hashed by the Secure Hash Algorithm 256-bit(SHA-256)for generating independently deterministic keys used in the multilevel stages.A piecewise pixel-level scrambling function is introduced to perform a dual flipping process controlled with an adaptive key for obscuring the spatial relationships between the adjacent pixels.Adynamicmasking scheme is presented for conducting a bit-level manipulation based on distinct keys that change over image regions,providing completely different encryption results on identical regions.To handle the global correlation between large-scale patterns,a chaotic index-map system is employed for shuffling image regions randomly across the image domain based on a logistic map seeded with a private key.Experimental results on a dataset of military images show the effectiveness of the proposed encryption method in producing excellent quantitative and qualitative results.The proposed method obtains uniform histogram distributions,high entropy values around the ideal(≈8 bits),Number of Pixel Change Rate(NPCR)values above 99.5%,and low Peak Signal-to-Noise Ratio(PSNR)over all encrypted images.This validates the robustness of the proposed method against cryptanalytic attacks,verifying its ability to serve as a practical basis for secure image transmission in defense systems.展开更多
文摘5G基站、分布式光伏(distributed photovoltaic,DPV)等分布式资源大规模参与配电网经济与电能质量等多目标优化调度,致使配电网调控模型决策变量复杂、求解时间慢等问题凸显。为此,提出一种考虑5G基站调控潜力和多资源协同的配电网分层分区优化方法。首先,考虑5G基站通信流量波动特性,建立计及闲置荷电状态(state of charge,SOC)约束的5G基站调控潜力模型。基于此,再建立配电网分层分区优化模型。上层以配电网综合效益最优为目标进行集中式调度,从而确定配电网分组投切电容器组、静止无功发生器等自身资源的动作方案。下层为分区调度,结合电压-功率灵敏度和考虑5G基站通信负荷的源荷不匹配度指标进行配电网物理分区,建立面向5G基站闲置SOC和DPV剩余容量的配电网分区协调优化模型,并采用二阶锥规划和同步型交替方向乘子法相结合的混合算法进行求解。最后,以改进的IEEE33节点配电网为算例,分析验证了所提方法的有效性。结果表明,所提方法能够提高配电网调控模型的求解能力,并提升配电网经济性和电压质量。
文摘Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military images.The proposed encryption method is based on multilevel security stages of pixel-level scrambling,bitlevel manipulation,and block-level shuffling operations.For having a vast key space,the input password is hashed by the Secure Hash Algorithm 256-bit(SHA-256)for generating independently deterministic keys used in the multilevel stages.A piecewise pixel-level scrambling function is introduced to perform a dual flipping process controlled with an adaptive key for obscuring the spatial relationships between the adjacent pixels.Adynamicmasking scheme is presented for conducting a bit-level manipulation based on distinct keys that change over image regions,providing completely different encryption results on identical regions.To handle the global correlation between large-scale patterns,a chaotic index-map system is employed for shuffling image regions randomly across the image domain based on a logistic map seeded with a private key.Experimental results on a dataset of military images show the effectiveness of the proposed encryption method in producing excellent quantitative and qualitative results.The proposed method obtains uniform histogram distributions,high entropy values around the ideal(≈8 bits),Number of Pixel Change Rate(NPCR)values above 99.5%,and low Peak Signal-to-Noise Ratio(PSNR)over all encrypted images.This validates the robustness of the proposed method against cryptanalytic attacks,verifying its ability to serve as a practical basis for secure image transmission in defense systems.
