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关键词： medical image encryption   Fisher-Yates scrambling   three-dimensional filter diffusion   bidirectional diffusion   S-box substitution  

摘要： A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box ***,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion *** three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of *** chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first ***,three-dimensional filter is applied to diffusion for further useful information *** key to the algorithm is generated by the combination of hash value of plaintext image and the input *** improves resisting ability of plaintext *** security analysis shows that the algorithm is effective and *** can resist common *** addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research.

关键词： 双碳目标   变压器   信息化   信息系统设计   混合架构  

摘要： 以变压器铁心车间生产流程为研究对象,开发了智能生产管家系统。采用B/S、C/S混合架构完成了计划管理系统模块(PMS)、仓库管理系统模块(WMS)、仓库控制系统模块(WCS)等相关功能,实现了变压器铁心车间从计划到执行、从设备到物料的一体化管控,有效解决了铁心车间各流程节点数据纸质化流转和数据孤岛等问题。

关键词： Breakdown voltage   Charge balance   Power MOSFET   Split gate   Super junction   Trench  

摘要： In this work, a new vertical power MOSFET (SJSGTPMOS) structure, using a double charge balanced technique, is proposed and designed for the first time. The double charge balance technique is achieved by splitting the Trench Poly-Si gate and converting the n-drift region into a stack of charge-balanced p/n pillars, which significantly improves the device performance and reduces the total requirement of gate charge as well as Gate-To-Drain Terminal Capacitive (Cgd) coupling. Using 2D-Silvaco ATLAS, the high-performance electrical characteristics output is achieved in our proposed device, compared with the conventional trench MOSFET. The proposed device gives excellent results of 0.94 pC Gate Charge (Qgd), 33.6% improvement in breakdown voltage, 74.1% and 99.29% improvements in two Baliga's Figure of Merits (FOM1 and FOM2), 91.62% in Cgd, at epilayer thickness of 1.2µm, showing the enhancement features of the proposed structure over the existing state-of-the-art, using two perfectly different charge balanced technique, without any impact on the gate control. © 2025 Seventh Sense Research Group.

关键词： electrocardiogram(ECG)signal denoising   empirical wavelet transform(EWT)   honey badge optimization(HBO)   adaptive hybrid filter   window function  

摘要： Cardiovascular diseases are the world’s leading cause of death;therefore cardiac health of the human heart has been a fascinating topic for *** electrocardiogram(ECG)signal is a comprehensive non-invasive method for determining cardiac *** health practitioners use the ECG signal to ascertain critical information about the human *** this article,swarm intelligence approaches are used in the biomedical signal processing sector to enhance adaptive hybrid filters and empirical wavelet transforms(EWTs).At first,the white Gaussian noise is added to the input ECG signal and then applied to the *** ECG signals are denoised by the proposed adaptive hybrid *** honey badge optimization(HBO)algorithm is utilized to optimize the EWT window function and adaptive hybrid filter weight *** proposed approach is simulated by MATLAB 2018a using the MIT-BIH dataset with white Gaussian,electromyogram and electrode motion artifact noises.A comparison of the HBO approach with recursive least square-based adaptive filter,multichannel least means square,and discrete wavelet transform methods has been done in order to show the efficiency of the proposed adaptive hybrid *** experimental results show that the HBO approach supported by EWT and adaptive hybrid filter can be employed efficiently for cardiovascular signal denoising.

关键词： 汽轮机热效率   输出功率稳定性   蒸汽初参数   热力循环系统   综合优化策略  

摘要： 本文旨在探讨火力发电厂汽轮机热效率提升的方法以及输出功率稳定性的优化策略。通过对汽轮机热效率的定义、计算方法及影响因素进行分析,提出了提高蒸汽初参数、采用蒸汽再热循环、优化热力循环系统、采用新型材料和技术等热效率提升方法。同时,针对输出功率稳定性,从温度变化、电压波动和控制系统稳定性等方面进行了影响因素分析,并提出了相应的改善措施。通过综合优化策略的实施,在某火力发电厂汽轮机系统中进行了案例分析,结果显示热效率和输出功率稳定性均得到了显著提升。本文的研究为能源行业的可持续发展提供了理论支撑和实践指导。

关键词： 功率电压解耦   配电网   PSO-CSA算法   分布式光伏   电压控制  

摘要： 针对分布式光伏并网带来的配电网电压波动和网损过大等问题,提出了基于功率电压解耦的配电网电压控制策略。首先分析了储能的输出特性和功率电压解耦控制特性;然后提出基于功率电压解耦的配电网电压控制策略;最后采用PSO-CSA算法求解优化模型,在改进后的IEEE 33节点配电系统进行算例分析。结果表明:所提模型在降低系统有功网损和提升电压质量方面表现更好,并且显著提高了配电网对可再生光伏的消纳能力。

关键词： 树脂绝缘   干式电力变压器   噪声   降低对策  

摘要： 树脂绝缘干式电力变压器作为电力系统中的重要设备,本身以重量轻、体积小、免维护、阻燃等优点,在城市电网中得到广泛应用。然而,随着城市配电系统的不断发展和居民环保意识的提高,变压器噪声问题日益严峻,成为了影响居民生活和办公环境的重要因素。本文深入分析了树脂绝缘干式电力变压器噪声的产生原因,提出了一系列降低噪声的对策,通过实施这些对策,可以有效降低树脂绝缘干式电力变压器的噪声,提高设备的运行效率和用户的满意度,为解决变压器噪声问题提供科学依据和技术支持,进而推动城市电网的可持续发展。

关键词： 互感器   放电特高频传感器   灵敏度   抗干扰  

摘要： 本文聚焦于互感器局部放电特高频传感器的性能研究。通过搭建试验平台,深入探究特高频传感器在不同放电量条件下的灵敏度特性以及在多种干扰类型环境中的性能变化情况。结果 表明,随着放电量从10pC增加到100pC,传感器不仅能够持续稳定地输出信号,而且灵敏度在一定范围内呈现上升趋势,说明传感器具有较宽的动态范围,能够适应不同强度的局部放电信号。传感器针对工频干扰有良好的抗干扰机制,能够在复杂的电力系统运行环境中,有效避免因工频干扰导致的检测误差,确保对互感器局部放电情况的准确监测。

关键词： 风电功率预测   Transformer   注意力机制   特征提取   长短期记忆网络   维数不变嵌入层  

摘要： 针对短期风电功率预测特征提取尺度单一问题,设计一种基于多尺度特征提取的Transformer短期风电功率预测模型(MTPNet)。首先,在Transformer构架的基础上,利用维数不变嵌入,设计多尺度特征提取网络挖掘风电功率序列本身时序特征,保证了特征提取时维数不被破坏;其次,利用融合自注意力机制的长短期记忆网络挖掘气象条件与功率之间的全局依赖关系;最后,融合风电功率序列本身时序特征和气象条件依赖关系,实现短期风电功率预测。实例仿真结果表明,MTPNet模型预测精度得到提升;消融实验证明了模型各模块的可靠性和有效性,具有一定的实用价值。

关键词： 无通信   频率响应   惯量模拟   海上风电场   多端柔性直流输电系统  

摘要： 为实现海上风电-多端柔直送出系统(offshore wind farms+voltage source converter-based multi-terminal DC,OWF+VSC-MTDC)对主网的频率支撑,该文提出了一种基于直流电压补偿的惯量协调控制(DC voltage compensationbased inertia coordinated control,VICC)方案,通过改变MTDC直流电压建立海上电网与主网的频率联系,使海上风电机组感应到主网频率动态后,通过其附加的超级电容充放电来模拟同步机的惯量响应。依据网侧换流站中建立的有功功率-直流电压-频率(P-udc-f)双下垂控制,分析了OWFs惯量功率影响下的MTDC直流电压-主网频率的非线性耦合特征。基于此提出了依据本地信息量测的直流电压补偿控制方案,以抵消OWFs惯量功率对频率传递的影响,使风电场精确模拟主网频率动态,为主网提供精准惯量支撑。此外,该文构建了OWF+VSC-MTDC系统的小信号模型,并对关键参数进行了稳定性分析与优化。最后,在MATLAB/Simulink环境中搭建了包含OWF+VSC-MTDC的电力系统模型,在负荷投切和电网故障工况下对VICC方案进行了验证和评估。结果表明,VICC方案可以在无通信条件下精确耦合海上电网频率与主网频率,使OWFs通过VSC-MTDC为主网提供精准惯量支撑,显著提升主网的频率稳定。