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关键词： 无人机群组   多任务   功率和频谱资源分配   联合优化   共信道干扰  

摘要： 针对有限频谱资源条件下无人机集群执行多任务时频谱资源共享不充分的问题，基于多任务将无人机集群分为多个群组，从信道分配和功率分配两个维度开展多任务频谱资源分配方法研究。为保证所有群组传输吞吐量的公平性，在考虑频谱复用和共信道干扰的情况下，以最大化最小群组传输吞吐量为目标，构建了面向无人机群组的频谱资源分配模型。为降低模型求解复杂度，提出了一种联合功率和频谱资源优化算法，利用改进遗传算法同时优化簇头无人机和成员无人机的信道分配，并通过凸优化方法分步优化了簇头无人机和成员无人机的传输功率，交替迭代实现问题求解。仿真结果表明，在仿真参数相同的情况下，群组吞吐量比基准算法平均至少提升16%，同时保证了群组传输的公平性。

关键词： 等离子喷涂功率   YSZ热防护涂层   扁平粒子   抗热震性能  

摘要： 为提高内燃机热效率，减少散热损失，在内燃机受热零部件表面制备热障陶瓷涂层来发展低散热内燃机，提升内燃机关键受热部件的隔热量和抗高温热冲击损伤能力。采用大气等离子喷涂技术制备了8YSZ/NiCrAlY双层热防护涂层。利用XRD、Raman和SEM等表征了YSZ粉体及其涂层的物相组成和显微结构，探究了不同喷涂功率对所制备YSZ涂层组织结构-物相组成及其力学性能的影响，特别是采用马弗炉加热-水淬方式在800℃评价了涂层的抗热震性能，并对其失效机制进行了初步探究。研究结果表明，随喷涂功率从35.75 kW增至42 kW，制备的YSZ涂层物相均由四方相氧化锆组成，涂层未熔融区减小甚至消失，形成明显的柱状晶区和等轴晶区；孔隙和微裂纹数量呈下降趋势，涂层变得更加致密，显微硬度呈先增大后降低趋势，而结合强度缓慢增加。所制备C4 （42 kW）YSZ涂层具有较好的显微硬度(817.15 ± 58.65 HV300g)和结合强度（66.37 ± 4.90 MPa）。在热冲击试验800次后，C4涂层表现出最好的抗热震性能，但对涂层微观组织结构和性能的损伤严重，已接近涂层热冲击寿命。

关键词： 变压器   故障诊断   轻量梯度提升机   特征变量   改进浣熊优化算法   卷积神经网络  

摘要： 为提高基于深度学习的变压器故障诊断精度，提出了基于油中溶解气体分析(Dissolvedgasanalysis,DGA)的LightGBM-ICOA-CNN变压器故障诊断方法。首先，基于变压器油中溶解气体含量对变压器特征变量进行丰富，利用轻量梯度提升机算法(Light gradient boosting machine,LightGBM)量化其重要性，实现特征变量优选；其次，引入改进浣熊优化算法(Improved coati optimization algorithm,ICOA)对卷积神经网络(Convolutional neural network,CNN)的学习率、卷积核大小与数量、全连接层神经元数量等超参数实现优化，提高模型诊断结果的准确率；最后，通过算例分析对建立的LightGBM-ICOA-CNN方法性能进行评估，验证了所提方法对变压器故障诊断的有效性，且收敛性较好，精度较高。

关键词： 短期风电功率   改进蛇优化算法   核极限学习机  

摘要： 为了对风电功率进行精确预测，基于互补集合经验模态分解（complementary ensemble empirical mode decomposition,CEEMD）、改进蛇优化算法（improved snake optimization,ISO）和核极限学习机（kernel extreme learning machine,KELM）提出了一种混合短期风电功率预测模型.首先，利用CEEMD将非平稳的风电功率数据分解为若干相对平稳的分量，以降低原始数据的不稳定性；然后，引入改进蛇优化算法对KELM参数进行优化，并对各平稳分量和残差构建CEEMD-ISO-KELM预测模型；最后，将各分量和残差的预测结果进行重构，得到最终的风电功率预测结果.仿真结果表明，与现有预测模型相比，本文提出的预测模型能够很好地预测风电功率的变化趋势，在短期风电功率预测中取得了较好的精度.

关键词： LLC   四元矩阵变压器   磁集成   寄生参数  

摘要： LLC变换器因其出色的软开关性能与低输出阻抗被广泛应用于电池储能变换器的功率级。在低压大电流工况下，LLC二次侧多采用矩阵变压器降低电流应力。在实际电路中，矩阵变压器体积占整个主功率部分25%左右，严重制约了装置功率密度的提高。且传统分立绕线式矩阵变压器寄生参数不可控，导致LLC输出电压跌落及开关尖峰，降低了装置可靠性。该文提出一种考虑损耗与寄生参数的LLC四元矩阵平面变压器集成优化设计方法。首先，基于四元集成磁心磁通分布特性提出分布式磁心损耗计算方法，建立变压器精确损耗模型。其次，通过建立变压器寄生电感和寄生电容求解模型，确定了变压器结构参数与寄生参数的映射关系，实现了变压器损耗、寄生电感、寄生电容流程化解耦设计，在保证变压器高效运行前提下寄生参数可控。最后，通过有限元仿真验证并搭建了两台250 W/3.3 V/48 V储能变换器实验样机。所提方法样机在84 A输出电流下，LLC效率为95%，集成矩阵变压器一、二次侧漏感降低为原先的30%，寄生电容被有效抑制，运行性能得到进一步提升。

关键词： MOSFET   Biosensor   Gate stack   Short channel effects (SCEs)   Transconductance   Sensitivity parameters   Electrical characteristics  

摘要： This study observes the MOSFET's performance concerning several biomolecules for use as a biosensor device. The double gate MOSFET with gate stack configuration has been chosen as the suggested device to surpass the limitations of short-channel effects (SCEs). The cavity was created to restrict the passage of charged and uncharged biological molecules so that they could be detected. These molecules fill the cavity, changing the device's electrical properties. The Double Gate MOSFET (DG-MOSFET) biosensor is subject to limitations such as Short Channel Effects (SCEs) and issues with the power supply. The suggested device decreased SCEs and it also demonstrates the potential benefits of having DG-MOSFETs with gate stacking for biosensor applications. Comparison of transconductance, the generating factor for transconductance, and sensitivity parameters such as Id and Vth sensitivity and Ion/Ioff sensitivity has been carried out in this study. The variation of temperature can influence the mobility of charge carriers within the semiconductor, affecting the conductance of the *** on the specific biomolecule being detected, changes in temperature can modulate the interaction between the biomolecule and the sensor surface, leading to alterations in the electrical properties of the device and these changes can be precisely measured, thereby enhancing the sensitivity of *** systematically varying the temperature, researchers can explore the thermodynamic and kinetic aspects of the binding events, allowing for fine-tuning of the sensor performance to meet specific application requirements.

关键词： Sensors   Electrodes   MOSFET   Graphene   Wire   Transducers   Sensitivity   Biosensor   chemical sensor   extended-gate   field-effect transistor (FET)   laser-induced graphene (LIG)  

摘要： Laser-induced graphene (LIG) stands out as a promising nanomaterial for applications in high-sensitivity, low-cost, and disposable chemical and biological sensing. However, LIG's metallic properties and weak field effect pose challenges to its integration into high-performance field-effect transistor (FET)-based sensors. This study presents an innovative approach wherein a LIG electrode, created through laser scribing on polyimide (PI) material, serves as a replicable sensing electrode that connects to the gate of a reusable metal-oxide-semiconductor FET (MOSFET) transducer. We implemented pH- and sodium-sensitive FET sensors employing two different LIG sensing electrodes: pristine LIG for pH sensing (30.9 mV/pH) and ion-selective membrane-coated LIG for sodium-ion sensing (-46.9 mV/dec). Various configurations of LIG-based FET sensors were explored to demonstrate the flexibility and versatility of our method, including direct laser scribing on diverse PI materials such as PI adhesive tape, PI-insulated Ag wire, and flexible printed circuit boards (FPCBs). Our findings highlight that LIG sensing electrodes, characterized by their ample surface area, cost-effectiveness, and disposability, are highly compatible with FET-based chemical sensors.

关键词： Electrostatic discharges   MOSFET   Integrated circuits   Electrostatic discharge protection   Technological innovation   System-on-chip   Reviews  

摘要： Electrostatic discharge (ESD) failure is a major integrated circuit (IC) reliability problem. On-chip ESD protection has drawn continuous R&D efforts for decades and becomes increasingly challenging for modern chips at advanced technology nodes where ESD protection device structures play foundational roles. This paper reviews key device innovation in modern on-chip ESD protection designs, leading to future ESD protection perspectives. Chip-level ESD design innovation, including ESD design methodologies, will be reviewed separately.

关键词： 心血管病学   双腔起搏器   变压器   心电图  

摘要： 患者男性,74岁,植入Vitatron C50 D(Model C50A4)型双腔起搏器11年,起搏器工作正常.在小区安装500kW变压器后于通电前后,不同距离下心电监护,以及Holter下均未发现变压器通电前后患者日常活动出现起搏频率、起搏感知、起搏功能等有异常.