Identification of denatured and normal biological tissues based on compressed sensing and refined composite multi-scale fuzzy entropy during high intensity focused ultrasound treatment

In high intensity focused ultrasound(HIFU)treatment,it is crucial to accurately identify denatured and normal biological tissues.In this paper,a novel method based on compressed sensing(CS)and refined composite multi-scale fuzzy entropy(RCMFE)is proposed.First,CS is used to denoise the HIFU echo signals.Then the multi-scale fuzzy entropy(MFE)and RCMFE of the denoised HIFU echo signals are calculated.This study analyzed 90 cases of HIFU echo signals,including 45 cases in normal status and 45 cases in denatured status,and the results show that although both MFE and RCMFE can be used to identify denatured tissues,the intra-class distance of RCMFE on each scale factor is smaller than MFE,and the inter-class distance is larger than MFE.Compared with MFE,RCMFE can calculate the complexity of the signal more accurately and improve the stability,compactness,and separability.When RCMFE is selected as the characteristic parameter,the RCMFE difference between denatured and normal biological tissues is more evident than that of MFE,which helps doctors evaluate the treatment effect more accurately.When the scale factor is selected as 16,the best distinguishing effect can be obtained.     

相关免疫逻辑函数的特征矩阵及其计数

本文定义了取值于任意抽象集合的逻辑函数的特征矩阵及其相关免疫性,用概率的方法研究了这类最一般的逻辑函数具有相关免疫性时,其特征矩阵的性质,由此给出了逻辑函数相关免疫的等价判别条件,据此给出了这类相关免疫逻辑函数的一种构造方法并对相关免疫逻辑函数的计数进行了研究,得到了一个一般性的下界.     

超高速分布放大光孤子传输系统分析

利用微扰理论方法推导了飞秒光孤子脉冲在具有一定带宽限制的分布放大光纤传输系统中传输时，脉冲宽度和频移的变化方程，此方程有稳态解，并得到稳定传输时，脉冲宽度及频移的解析表达式。     

大学物理实验教学模式改革探索与研究

大学物理实验教学模式改革的目标是紧密围绕课程培养方案,坚持以学生为中心,通过互联网+技术,改革课堂教学模式和教学方法,提高课程的整体质量和教学水平.通过将传统的课堂教学模式与慕课堂、翻转课堂、线上线下混合式教学、虚拟仿真等新型教学模式相结合,使之适应现代化高等教育的需求,成为能够对学生核心素质提升和专业能力培养...     

高频线阵的研制

本文描述了一种用于侧扫声纳的高频线列阵，该阵由中心频率分别为１００ＫＨｚ和５００ＫＨｚ的两部分构成。由于采用阵元加权排列和充分利用有效工作面积，该阵具有尖锐的主瓣，较高的主、副瓣比和较高的发射、接受灵敏度（１００ＫＨｚ时分别为１７４ｄＢ，５００ＫＨｚ时分另为１７４ｄＢ、－１８３ｄＢ），技术指标达到国外同类高频线阵的水平。满足侧扫声呐的尖波束、低副瓣、大功率、高灵敏度，深水（１００ｍ）使用的要求，本     

Adaptive robust control of chaotic oscillations in power system with excitation limits

With system parameters falling into a certain area, power system with excitation limits experiences complicated chaotic oscillations which threaten the secure and stable operation of power system. In this paper, to control these unwanted chaotic oscillations, a straightforward adaptive chaos controller based on Lyapunov asymptotical stability theory is designed. Since the presented controller does not need to change the controlled system structure and not to use any information of system except the system state variables, the designed controller is simple and desirable. Simulation results show that the proposed control law is very effective. This work is helpful to maintain the power system＇s security operation.[第一段]     

具有最高代数次数的2n元n维Bent函数的构造

本文给出了代数次数达到最高的一类布尔置换的代数标准形 ;并用m序列的状态转移矩阵和所得置换 ,构造了一类代数次数达到最高的 2n元n维Bent函数 ,用这类函数所构造的S盒具有较高的安全强度 .     

导电聚合物的进展

大多数聚合物一直都是作为良好的电绝缘体广泛地应用于各个方面,但近年来已发现聚合物也可以作成半导体、导体、甚至超导体。由于其本身的若干特点,如原料易得,力学性质良好,合成加工方便,组成结构变化的多样性等,加强了人们对其电性质的研究兴趣。导电聚合物的种类颇多,每年发表的论文和评述文章也很多。研究工作虽然取得了重大的进展,但对其基本性质的了解还是很有限的。本文将着重对共轭体系导电聚合物的进展和应用,作一简要的综述。     

聚酯直接缩聚反应的机理探讨

聚酯的直接缩聚合成法是从合成聚羟基苯甲酸发展而来,已成功地用于合成聚芳酯,但有关反应机理的研究报导很少。我们亦对反应机理进行了探讨,实验方法是先配制定量的对甲苯磺酰氯(TsCl)-吡啶溶液,溶解后立即用移液管将溶液移至比色皿中,加入不同量的二甲基甲酰胺(DMF),用可见-紫外光分光光度法跟踪反应,并用红外光谱法测定反应的中间产物,结果报导如下。