级联型储能功率变换系统控制策略综述

级联型储能功率变换系统广泛应用于高压大容量场合,对电力系统起到削峰填谷的作用,其控制策略的好坏直接影响到储能系统的性能和可靠性.因此,近年来对级联型储能功率变换系统控制策略的研究引起了广泛关注,国内外学者对其进行了大量研究,主要可分为功率控制、均衡控制及容错控制三个方面,根据这三个方面对级联型储能功率变换系统控制策略进...     

FFCAEs: An efficient feature fusion framework using cascaded autoencoders for the identification of gliomas

Intracranial tumors arise from constituents of the brain and its meninges. Glioblastoma (GBM) is the most common adult primary intracranial neoplasm and is categorized as high-grade astrocytoma according to the World Health Organization (WHO). The survival rate for 5 and 10 years after diagnosis is under 10%, contributing to its grave prognosis. Early detection of GBM enables early intervention, prognostication, and treatment monitoring. Computer-aided diagnostics (CAD) is a computerized process that helps to differentiate between GBM and low-grade gliomas (LGG), using the perceptible analysis of magnetic resonance (MR) of the brain. This study proposes a framework consisting of a feature fusion algorithm with cascaded autoencoders (CAEs), referred to as FFCAEs. Here we utilized two CAEs and extracted the relevant features from multiple CAEs. Inspired by the existing work on fusion algorithms, the obtained features are then fused by using a novel fusion algorithm. Finally, the resultant fused features are classified with the Softmax classifier to arrive at an average classification accuracy of 96.7%, which is 2.45% more than the previously best-performing model. The method is shown to be efficacious thus, it can be useful as a utility program for doctors.     

带有大输出时滞的ODE–热方程级联系统的观测器设计

为了估计系统的状态并补偿输出时滞,本文提出一种新颖的观测器设计方法应用在常微分方程(ODE)-热方程级联系统中.不同于传统观测器的设计方法,该方法的核心思想是将大时滞划分为若干段小时滞,再设计一串级联的子观测器逐步地估计系统的状态.这种方法的优势在于对于大时滞仍有效.本文通过backstepping-like方法实现了原系统与目标系统的等价变换,结合Lyapunov-Krasovskii方法和线性矩阵不等式理论,得到了误差系统指数稳定的结果.最后,通过仿真实例验证了级联观测器的有效性.     

Cascade DNA Circuits Mediated CRISPR-Cas12a Fluorescent Aptasensor based on Multifunctional Fe3O4@hollow-TiO2@MoS2 Nanochains for Tetracycline Determination

Herein, for the first time, the CRISPR-Cas12a system is combined with aptamer, cascaded dynamic DNA network circuits, and Fe₃O₄@hollow-TiO₂@MoS₂ nanochains (Fe₃O₄@h-TiO₂@MoS₂ NCs) to construct an efficient sensing platform for tetracycline (TC) analysis. In this strategy, specific recognition of the target is transduced and amplified into H1-H2 duplexes containing the specific sequence of Cas12a-crRNA through an aptamer recognition module and the dual amplification dynamic DNA network. Subsequently, the obtained activated Cas12a protein non-specifically cleaves the adjacent reporter gene ssDNA-FAM to dissociate the FAM molecule from the quencher Fe₃O₄@h-TiO₂@MoS₂ NCs, resulting in the recovery of the fluorescence signal and further signal amplification. Particularly, the synthesized multifunctional Fe₃O₄@h-TiO₂@MoS₂ NCs composites also exhibit superb magnetic separability and photocatalytic degradation ability. Under optimal conditions, the aptasensor displays a distinct linear relationship with the logarithm of TC concentration, and the limit of detection is as low as 0.384 pg mL⁻¹. Furthermore, the results of spiked recovery confirm the viability of the proposed aptasensor for TC quantification in real samples. This study extends the application of the CRISPR-Cas12a system in the field of analytical sensing and contributes new insights into the exploration of reliable tools for monitoring and treating hazards in food and environment.     

级联信道的案例式教学方法

级联信道是“信息论基础”中的重要概念之一，其性质“数据处理定理”极为重要，但相关概念较抽象，传统教学方法的实际效果有待提高。以易懂的“外国人中文传话”游戏切入，将抽象概念具体化，由此引入级联信道定义及性质，在理论推导数据处理定理的基础上，结合该定理的实际应用让学生理解“信息不增”与数据处理的内在关系。此外在教学中植入文化自信、理论与实践结合等思政元素。     

无刷级联双馈感应发电机稳压控制策略

针对级联双馈感应电机作为无刷变速恒频发电机带负载独立运行控制问题，设计了一种新型稳压控制策略。基于级联双馈感应电机作为无刷变速恒频发电机运行的数学模型，设计了一种易于实施的间接磁场定向矢量控制，可在转速和负载单独变化或一起变化时，稳定发电机的输出电压幅值和频率。同时，电压控制器设计避免了前馈补偿及其所需额外电流传感器的应用，即通过合理设计抑制了耦合效应带来的扰动。利用所搭建的级联双馈感应电机测试平台开展了实验研究，测试结果验证了电压控制器的稳压性能。