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四川大学学报（自然科学版） 2024年第2期61卷 36-39页

作者：祝崇涵张付臣穆春来重庆工商大学数学与统计学院/统计智能计算与监测重庆市重点实验室重庆400067 重庆大学数学与统计学院重庆401331

本文研究了一个广义Lorenz系统的平衡点的稳定性(全局指数稳定、全局渐近稳定)及不稳定的判据,获得了系统的全局吸引性,并推广了已有的一些混沌演化研究方法.

关键词：广义Lorenz系统稳定性吸引域

Structured condition numbers and statistical condition estimation for the LDU factorization

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Applied Mathematics(A Journal of Chinese Universities) 2020年第3期35卷 332-348页

作者： Mahvish Samar Aamir Farooq mu chun-lai College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In this article, we consider the structured condition numbers for LDU, factorization by using the modified matrix-vector approach and the differential calculus, which can be represented by sets of parameters. By setting the specific norms and weight parameters, we present the expressions of the structured normwise, mixed, componentwise condition numbers and the corresponding results for unstructured ones. In addition, we investigate the statistical estimation of condition numbers of LDU factorization using the probabilistic spectral norm estimator and the small-sample statistical condition estimation method, and devise three algorithms. Finally, we compare the structured condition numbers with the corresponding unstructured ones in numerical experiments.

关键词： LDU factorization Structured condition number Normwise condition number Mixed condition number Componentwise condition number

Low-noise and low-power pixel sensor chip for gas pixel detectors

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Nuclear Science and Techniques 2024年第3期35卷 142-152页

作者： Zhuo Zhou Shi-Qiang Zhou Dong Wang Xiang-Ming Sun Chao-Song Gao Peng-Zhen Zhu Wei-Ping Ren Jun Liu mu-Xian Li Chen Lian chun-lai Dong PLAC Key Laboratory of Quark and Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China

Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in *** pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μ*** array is divided into 16 subarrays,with pixels of 400 rows×32 columns per *** pixel incorporates two charge sensors:a diode sensor and a Topmetal *** in-pixel circuit primarily consists of a charge-sensitive amplifier for energy measurements,a discriminator with a peak-holding circuit,and a time-to-amplitude converter for time-of-arrival *** pixel of Topmetal-M2 has a charge input range of~0-3 k e-,a voltage output range of~0-180 mV,and a charge-voltage conversion gain of~59.56μV∕e-.The average equivalent noise charge of Topmetal-M2,which includes the readout electronic system noise,is~43.45 e-.In the scanning mode,the time resolution of Topmetal-M2 is 1 LSB=1.25μs,and the precision is^()7.41μ*** an operating voltage of 1.5 V,Topmetal-M2 has a power consumption of~49 mW∕cm~*** this article,we provide a comprehensive overview of the chip architecture,pixel working principles,and functional behavior of ***,we present the results of preliminary tests conducted on Topmetal-M2,namely,alpha-particle and soft X-ray tests.

关键词： Charge collection Gas detectors Semiconductor detectors X-ray detectors

Generating animatable 3D cartoon faces from single portraits

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虚拟现实与智能硬件（中英文） 2024年第4期6卷 292-307页

作者： Chuanyu PAN Guowei YANG Taijiang mu Yu-Kun lai Department of Electrical Engineering and Computer Sciences University of California BerkeleyBerkeley CA 94704USA Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China School of Computer Science and Informatics Cardiff UniversityCardiff CF244AGUK

Background With the development of virtual reality(VR)technology,there is a growing need for customized 3D ***,traditional methods for 3D avatar modeling are either time-consuming or fail to retain the similarity to the person being *** study presents a novel framework for generating animatable 3D cartoon faces from a single portrait *** First,we transferred an input real-world portrait to a stylized cartoon image using *** then proposed a two-stage reconstruction method to recover a 3D cartoon face with detailed *** two-stage strategy initially performs coarse estimation based on template models and subsequently refines the model by nonrigid deformation under landmark ***,we proposed a semantic-preserving face-rigging method based on manually created templates and deformation *** Compared with prior arts,the qualitative and quantitative results show that our method achieves better accuracy,aesthetics,and similarity ***,we demonstrated the capability of the proposed 3D model for real-time facial animation.

关键词： 3D reconstruction Cartoon face reconstruction Face rigging Stylized reconstruction Virtual reality

粘性Hamilton-Jacobi方程的熄灭(英文)

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四川大学学报（自然科学版） 2009年第1期46卷 15-20页

作者：田娅穆春来重庆邮电大学数理学院重庆400065 重庆大学数理学院重庆400030

作者研究了初边值问题ut-△u-u＋｜△u｜^p=0，P∈（0，1）的非负古典解的有限时间熄灭，证明了熄灭现象的发生与区域Ω有关．对于Cauchy问题，上述方程的古典解在有限时间熄灭与否依赖于初值u0（x）在｜x｜→∞时的性态．

关键词：熄灭 Hamilton—Jacobi方程初边值问题

带梯度项的半线性抛物方程解的生命周期(英文)

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四川大学学报（自然科学版） 2008年第6期45卷 1323-1328页

作者：田娅穆春来重庆邮电大学数理学院重庆400065 重庆大学数理学院重庆400030

作者考虑了带梯度项的半线性抛物方程的柯西问题,在某些假定条件下得出解的生命周期.

关键词：生命周期爆破解半线性抛物方程梯度项

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一类带记忆边界条件波动系统解的长时间性态

高校应用数学学报（A辑） 2011年第2期26卷 127-136页

作者：钟越赖绍永穆春来西南财经大学应用数学系四川成都610074 四川师范大学文理学院四川成都610101 重庆大学应用数学系重庆400067

研究一类带记忆边界条件波动系统解的长时间性态.在初边值满足一定条件时,利用Faedo-Galerkin近似方法得到了系统解的存在唯一性.使用扰动能量方法,证明了系统解的一致衰减性.

关键词：波动系统 Faedo-Galerkin近似扰动能量方法记忆边界条件

一个用于图像分割的p-Laplace方程模型(英文)

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四川大学学报（自然科学版） 2011年第4期48卷 733-737页

作者：周彬穆春来西安科技大学理学院西安710054 重庆大学数学与统计学院重庆401331

作者研究了一个用于图像分割的新模型.通过结合几个尺度函数,一个偏微分方程模型被用于提取物体的边界.活动轮廓线的运动受一个p-Laplace方程驱动.作者给出的水平集模型能够处理一些复杂情况下的拓扑变化,并且能够提取一些深度凹陷的物... 详细信息

作者研究了一个用于图像分割的新模型.通过结合几个尺度函数,一个偏微分方程模型被用于提取物体的边界.活动轮廓线的运动受一个p-Laplace方程驱动.作者给出的水平集模型能够处理一些复杂情况下的拓扑变化,并且能够提取一些深度凹陷的物体边界,相关的演化过程平滑且无需初始化.该方法耗费较小,几个数值算例显示了该方法的有效性.

关键词： p-拉普拉斯方程图像分割变分水平集