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起动负浮力射流中涡环形成与演化的实验研究
On the Vortex Ring Formation and Evolution in Negatively Buoyant Jet [PDF]
陈盛文, 高磊
Applied Physics (APP) , 2019, DOI: 10.12677/APP.2019.94023

Abstract:

本文对负浮力涡环的形成与演化的动力学特性进行了实验研究。对小冲程比(L/D = 2、3)情况下产生的浮力涡环的近场的演化进行了分析，发现随着理查德森数Ri增大，涡环的生长半径变大，涡环的运动速度减小，相应的动力学参数(水力冲量、环量等)也变小。并求得浮力涡环的冲量与速度，与细核涡环理论模型公式求得的冲量与速度对比，发现浮力涡环是符合细核涡环特性。
In this paper, the formation and evolution of negative buoyancy vortex rings are studied experimentally. For small stroke ratio (L/D = 2, 3) cases, the evolution of the buoyant vortex ring in the near field is investigated. It is found that as Richardson number Ri increases, the growth rates of the vortex ring radius, as well as its translational velocity are reduced. The kinetic parameters of the buoyant vortex ring, i.e., the hydrodynamic impulse and circulation, are also diminished by Ri. The impulse and velocity of the buoyancy vortex ring are obtained and compared with those of the thin core vortex ring model. It is found that the buoyant vortex ring conforms to the characteristics of thin core vortex ring model.

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MPPSK通信系统中的检测与信道编码的研究
Research on Detection and Channel Coding in MPPSK Communication System [PDF]
盛晶晶, 陈贤卿
Hans Journal of Wireless Communications (HJWC) , 2020, DOI: 10.12677/HJWC.2020.105007

Abstract:

为了尽可能地利用有限的频谱资源，本文根据多元位置相移键控(MPPSK)调制信号的特点，研究基于多分类支持向量机(SVM)的非线性方法在低阶MPPSK通信系统中的检测性能，并对SVM输入特征向量做降维处理，降低系统复杂度。为了进一步提升MPPSK系统在低信噪比下的误码率性能，本文引入低密度奇偶校验码(LDPC)作为信道编码用以抵抗信道噪声。仿真结果表明，多分类SVM非线性检测在较少的特征向量维数中，可获得最多10 dB的信噪比增益，经LDPC译码后系统性能可进一步提升8 dB。因而，在MPPSK通信系统中选择多分类SVM方法不仅可以提升检测性能，而且抗干扰能力更强，传输码率更高。
In order to make the best use of the limited spectrum resources, this paper studies the detection performance of the nonlinear method based on the multiple classification support vector machine (SVM) in the low-order multiple position phase-shift keying (MPPSK) communication system according to the characteristics of MPPSK modulated signals, and the dimension-reduction processing for the input feature vectors of SVM is performed, so that the complexity of system is reduced. In order to further improve the bit error rate performance of MPPSK system at the low signal noise rate (SNR), the low density parity check code (LDPC) is introduced by this paper as the channel coding to resist the channel noise. The simulation results have shown that the maximum SNR gain of 10 dB at the less feature vector dimensions can be obtained by the multiple classification SVM nonlinear detection, and the system performance can be further increased by the 8 dB after decoding by the LDPC. Therefore, the multiple classification SVM method is chosen in the MPPSK communication system, not only can the detection performance is improved, but also the anti-interference ability is stronger and the transmission code rate is higher.

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倾斜图像矫正算法的研究
Research on Tilted Image Correction Algorithm [PDF]
盛晶晶, 陈贤卿
Journal of Image and Signal Processing (JISP) , 2020, DOI: 10.12677/JISP.2020.94029

Abstract:

为提高倾斜图像矫正效果、降低计算复杂度，本文深入分析了TILT (Transform invariant low-rank textures)算法并对其进行优化改进，包括凸优化算法、拉格朗日乘子法、多分辨策略优化方法等。为了验证算法有效性，本文对车牌、建筑、文字以及人脸等不同类型的倾斜图像进行矫正实验。仿真结果表明，TILT及其改进算法对多种角度甚至是较大角度倾斜图像的矫正都可获得较为理想结果，且改进算法可有效降低计算复杂度，因而该算法在图像的后续处理、识别等领域具有广泛的应用前景。
In order to improve the tilt image correction effect and reduce the computational complexity, this paper analyzes and optimizes the TILL (Transform invariant low-rank textures) algorithm, including the convex optimization algorithm, the Lagrange multiplier algorithm, the multi-resolution strategy optimization algorithm, etc. In order to verify the validity of the algorithm, this paper corrects different types of tilt images, such as license plate, building, text and face. The simulation results show that TILT and its improved algorithm can obtain more ideal results for the correction of tilt images from various angles even larger angles, and the improved algorithm can effectively reduce the computational complexity, so the algorithm has a wide range of applications in the fields of image follow-up processing and recognition.

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基于多元表征的中学数学之椭圆曲线与方程教学设计
Teaching Design of Elliptic Curves and Equations in High School Mathematics Teaching Based on Multivariate Representation [PDF]
陈裕城, 张盛奎
Advances in Education (AE) , 2024, DOI: 10.12677/AE.2024.142309

Abstract: 多元表征是数学教育研究的热点，同时，椭圆曲线与方程作为高中数学教学的重难点，相关的研究也很多，但关于多元表征在椭圆曲线与方程教学中的应用却少有论及。本文以数学多元表征理论为基础，对椭圆曲线与方程进行教学设计。教学设计从学生学习时认知的心理机制出发，引导学生逐步精致对椭圆曲线与方程的理解，最终达到对椭圆曲线与方程的深度理解。
Multimodal representation is a hot topic in mathematics education research. At the same time, elliptic curves and equations are key difficult points in high school mathematics teaching, and there is a lot of research related to them. However, there is little discussion about the application of multi-modal representation in the teaching of elliptic curves and equations. This article, based on the theory of mathematical multimodal representation, focuses on the instructional design of elliptic curves and equations. The instructional design starts from the cognitive psychology mechanisms of students’ learning, guiding students to gradually develop a refined understanding of elliptic curves and equations, ultimately achieving a deep comprehension of them.

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电针对大鼠不同脑区β-内啡肽含量的影响
陈启盛
科学通报 , 1983,

Abstract: 我们曾报告,大鼠电针镇痛效果与全脑和垂体内β-内啡肽含量变化密切相关。但各脑区β-内啡肽分布不均,所发挥的生理效应也不尽相同。为了进一步研究β-内啡肽在电针镇痛中的作用部位,我们测定了电针镇痛时大鼠不同脑区β-内啡肽含量的变化。

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中国埃拉飞虱属一新种记述(同翅目：飞虱科)
陈祥盛
昆虫学报 , 2002,

Abstract: 记述采自我国新疆维吾尔族自治区的埃拉飞虱属一新种，新疆埃拉飞虱Elachodelphaxxinjiangensissp.nov.。模式标本保存于贵州大学昆虫研究所。新种与该属模式种E.metcalfi(Kusnezov,1929)近缘，但新种以头顶端半部、额基半部深褐色，颊黑褐色；阳基侧突端外角及基内角呈角状突出；阳茎背缘波曲，具4齿，腹缘中部凹陷，该处亦具4齿；膈下半部两侧不具小齿等特征可明显区别。

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电针对大鼠不同脑区β-内啡肽含量的影响
陈启盛
科学通报 , 1983,

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大鼠电针镇痛效果与脑和垂体中β-内啡肽含量的关系——放射免疫分析
陈启盛
科学通报 , 1981,

Abstract: 国内外许多文献报告内源性鸦片样物质在针刺镇痛过程中起着十分重要的作用。但针刺镇痛时脑和垂体内β-内啡肽含量的变化迄今未见报道。

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信息管理学专业教育向何处去?——从信息管理人才信息结构谈起
陈耀盛
中国图书馆学报 , 2000,

Abstract: 在电子信息网络环境和市场经济环境下,信息管理学的学科定位应是横向的普适工具、方法学科;应培养以现代信息技术为支撑、以经济与管理知识为背景、广博科学文化与语言工具基础、宽厚横向信息管理知识为核心、专门领域信息管理为发展方向的人才,办出专业特色。参考文献5。

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试论信息管理
陈耀盛
中国图书馆学报 , 1997,

Abstract:

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