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Science China Mathematics 2018年第9期61卷 1711-1732页

作者： Chunlin Wu Zhifang Liu shuang wen School of Mathematical Sciences Nankai University

Variational methods have become an important kind of methods in signal and image restoration—a typical inverse problem. One important minimization model consists of the squared ?_2 data fidelity(corresponding to Gaussian noise) and a regularization term constructed by a potential function composed of first order difference operators. It is well known that total variation(TV) regularization, although achieved great successes,suffers from a contrast reduction effect. Using a typical signal, we show that, actually all convex regularizers and most nonconvex regularizers have this effect. With this motivation, we present a general truncated regularization framework. The potential function is a truncation of existing nonsmooth potential functions and thus flat on(τ, +∞) for some positive τ. Some analysis in 1 D theoretically demonstrate the good contrast-preserving ability of the framework. We also give optimization algorithms with convergence verification in 2 D, where global minimizers of each subproblem(either convex or nonconvex) are calculated. Experiments numerically show the advantages of the framework.

关键词： signal and image restoration inverse problem contrast-preserving variational method regularization potential function truncated regularization ADMM

Grasp evaluation and contact points planning for polyhedral objects using a ray-shooting algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第3期13卷 218-231页

作者： shuang-quan wen Tie-jun WU Department of Control Science and Engineering Zhejiang UniversityHangzhou 310027China

Grasp evaluation and planning are two fundamental issues in robotic grasping and dexterous manipulation. Most traditional methods for grasp quality evaluation suffer from non-uniformity of the wrench space and a dependence on the scale and choice of the reference frame. To overcome these weaknesses, we present a grasp evaluation method based on disturbance force rejection under the assumption that the normal component of each individual contact force is less than one. The evaluation criterion is solved using an enhanced ray-shooting algorithm in which the geometry of the grasp wrench space is read by the support mapping. This evaluation procedure is very fast due to the efficiency of the ray-shooting algorithm without linearization of the friction cones. Based on a necessary condition for grasp quality improvement, a heuristic searching algorithm for polyhedral object regrasp is also proposed. It starts from an initial force-closure unit grasp configuration and iteratively improves the grasp quality to find the locally optimum contact points. The efficiency and effectiveness of the proposed algorithms are illustrated by a number of numerical examples.

关键词： Force closure Grasp quality evaluation Multifingered grasp Grasping planning Ray-shooting

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“梗文化”的生成与传播机理研究

齐齐哈尔大学学报（哲学社会科学版） 2024年第6期 29-31页

作者：郎文静王宗双安徽农业大学马克思主义学院安徽合肥230036 合肥师范学院马克思主义学院安徽合肥230001

“梗文化”在本质上属于一种亚文化,它已深深影响大众的日常生活,成为人们社交的重要表达方式。“梗文化”通过符号重构实现语义变更而产生,在情感认同、迷因传播、技术赋权和资本裹挟的多重推动下得以广泛传播,是在网络文化中形成的独... 详细信息

“梗文化”在本质上属于一种亚文化,它已深深影响大众的日常生活,成为人们社交的重要表达方式。“梗文化”通过符号重构实现语义变更而产生,在情感认同、迷因传播、技术赋权和资本裹挟的多重推动下得以广泛传播,是在网络文化中形成的独特语言表达风尚,是新媒体语境下的一种传播现象。

关键词： “梗文化” 符号传播

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An Approximation Algorithm for P-prize-collecting Set Cover Problem

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Journal of the Operations Research Society of China 2023年第1期11卷 207-217页

作者： Jin-shuang Guo wen Liu Bo Hou School of Mathematical Sciences Hebei Key Laboratory of Computational Mathematics and ApplicationsHebei Normal UniversityShijiazhuang050024HebeiChina

In this paper,we consider the P-prize-collecting set cover(P-PCSC)problem,which is a generalization of the set cover *** this problem,we are given a set system(U,S),where U is a ground set and S⊆2U is a collection of subsets satisfying∪S∈SS=*** subset in S has a nonnegative cost,and every element in U has a nonnegative penalty cost and a nonnegative *** goal is to find a subcollection C⊆S such that the total cost,consisting of the cost of subsets in C and the penalty cost of the elements not covered by C,is minimized and at the same time the combined profit of the elements covered by C is at least P,a specified profit *** main work is to obtain a 2f+ε-approximation algorithm for the P-PCSC problem by using the primal-dual and Lagrangian relaxation methods,where f is the maximum frequency of an element in the given set system(U,S)andεis a fixed positive number.

关键词： P-prize-collecting set cover problem Approximation algorithm Primal-dual Lagrangian relaxation

基于超快热电效应及自旋热电子学效应的THz波产生

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太赫兹科学与电子信息学报 2024年第8期22卷 807-812,822页

作者：冯正孙松何康文爽中国工程物理研究院电子工程研究所四川绵阳621999 中国工程物理研究院微系统与太赫兹研究中心四川成都610200

飞秒激光泵浦光电导天线、磁性异质结构、电光晶体、空气等会产生太赫兹脉冲,其产生原理主要基于飞秒激发下载流子、电极化的瞬态变化等非热效应。与此同时,飞秒激光泵浦物质不可避免地会产生超快热效应。近年来,基于超快热电效应以及... 详细信息

飞秒激光泵浦光电导天线、磁性异质结构、电光晶体、空气等会产生太赫兹脉冲,其产生原理主要基于飞秒激发下载流子、电极化的瞬态变化等非热效应。与此同时,飞秒激光泵浦物质不可避免地会产生超快热效应。近年来,基于超快热电效应以及与自旋相关的超快自旋热电子学效应产生太赫兹波获得越来越多的关注。本文详细介绍了利用塞贝克效应/能斯特效应这两种热电效应,以及自旋塞贝克效应/反常能斯特效应这两种自旋热电子学效应产生太赫兹波的研究进展。超快热电效应及超快自旋热电子学效应已在太赫兹产生方面展现出巨大潜力,有望推动太赫兹源及相关技术的发展。

关键词：热效应自旋热效应超快太赫兹波产生塞贝克效应能斯特效应自旋塞贝克效应反常能斯特效应

群体感知工具对社会调节学习的驱动因素与作用机制研究——基于扎根理论的质性分析

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电化教育研究 2024年第5期45卷 42-50,66页

作者：尹兴翰叶俊民于爽罗晟任文司开颜华中师范大学人工智能教育学部湖北武汉430079 华中师范大学计算机学院湖北武汉430079

计算机支持的协作学习中的群体感知工具,能够帮助学习者监控和反思学习过程,对促进社会调节学习起着重要作用。但当前研究主要关注群体感知工具的设计及其效果验证,而群体感知工具对社会调节学习的作用机制及驱动因素尚不明晰。因此,文... 详细信息

计算机支持的协作学习中的群体感知工具,能够帮助学习者监控和反思学习过程,对促进社会调节学习起着重要作用。但当前研究主要关注群体感知工具的设计及其效果验证,而群体感知工具对社会调节学习的作用机制及驱动因素尚不明晰。因此,文章以探索群体感知工具对社会调节学习的作用机理为目标,采用扎根理论研究方法,通过深度访谈获取学习者在协作学习活动中使用群体感知工具的经历、感受、体验等数据,借助质性分析软件对数据进行三级编码,最终构建了“刺激—感知—调节”理论模型。研究发现,学习者利用群体感知工具可以促进自我调节、同伴调节和集体调节学习,并且受到个体因素、教学因素及环境因素的驱动,在此过程中,学习者需要经历群体感知接收与理解,包括信息查看、信息选择、价值判断、自我比较和意义建构等过程。针对上述结论,文章给出相应教学启示,包括引导学习者理解群体感知工具的内容,辅助学习者应用群体感知工具进行调节等。

关键词：社会调节学习群体感知工具作用机制扎根理论质性分析

Spatiotemporal Instability of Ultrashort Pulses in Dispersive Self-Focusing Media

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Chinese Physics Letters 2001年第6期18卷 776-778页

作者： wen shuang-Chun FAN Dian-Yuan National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Spatiotemporal instability in dispersive self-focusing media is investigated on the basis of a modified nonlinear Schrödinger equation(NLSE)beyond the slowly varying envelope *** is found that,for both normal and anomalous dispersions,space-time focusing may lead to the appearance of new temporal instability regions for some range of spatial *** physical origin of the new instability regions lies in the part of space-time coupling related to the fourth-order ***,space-time focusing shrinks the instability regions and slightly reduces the maximum growth rates of the original spatiotemporal instability gain spectra obtained from the standard NLSE.

关键词： slightly shrink envelope

XELOX(capecitabine plus oxaliplatin)plus bevacizumab(anti-VEGF-A antibody)with or without adoptive cell immunotherapy in the treatment of patients with previously untreated metastatic colorectal cancer:a multicenter,open-label,randomized,controlled,phase 3 trial

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2104-2113页

作者： Qiu-Zhong Pan Jing-Jing Zhao Liang Liu Dong-Sheng Zhang Li-Ping Wang wen-Wei Hu De-Sheng weng Xiang Xu Yi-Zhuo Li Yan Tang Wei-Hong Zhang Jie-Yao Li Xiao Zheng Qi-Jing Wang Yong-Qiang Li Tong Xiang Li Zhou shuang-Ning Yang Chen Wu Rong-Xing Huang Jia He Wei-Jiao Du Lu-Jun Chen Yue-Na Wu Bin Xu Qiong Shen Yi Zhang Jing-Ting Jiang Xiu-Bao Ren Jian-Chuan Xia State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerCollaborative Innovation Center for Cancer MedicineSun Yat-Sen University Cancer CenterGuangzhouGuangdong 510060PR China Department of Biotherapy Sun Yat-Sen University Cancer CenterGuangzhouGuangdong 510060PR China Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for CancerTianjin 300060PR China Key Laboratory of Cancer Immunology and Biotherapy Tianjin 300060PR China Department of Biotherapy/Immunology Tianjin Medical University Cancer Institute and HospitalTianjin 300060PR China Department of Medical Oncology Sun Yat-sen University Cancer CenterGuangzhou 510060PR China Department of Oncology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052PR China Department of Tumor Biological Treatment the Third Affiliated Hospital of Soochow UniversityChangzhouJiangsu 213003PR China Jiangsu Engineering Research Center for Tumor Immunotherapy ChangzhouJiangsu 213003PR China Institute for Cell Therapy of Soochow University ChangzhouJiangsu 213003PR China Department of Stem Cell&Regenerative Medicine State Key Laboratory of TraumaBurn and Combined InjuryDaping HospitalArmy Medical UniversityChongqing 400042PR China Imaging Diagnosis and Interventional Center Sun Yat-sen University Cancer CenterGuangzhouGuangdong 510060PR China

Fluoropyrimidine-based combination chemotherapy plus targeted therapy is the standard initial treatment for unresectable metastatic colorectal cancer(mCRC),but the prognosis remains *** phase 3 trial(***:NCT03950154)assessed the efficacy and adverse events(AEs)of the combination of PD-1 blockade-activated DC-CIK(PD1-T)cells with XELOX plus bevacizumab as a first-line therapy in patients with mCRC.A total of 202 participants were enrolled and randomly assigned in a 1:1 ratio to receive either first-line XELOX plus bevacizumab(the control group,n=102)or the same regimen plus autologous PD1-T cell immunotherapy(the immunotherapy group,n=100)every 21 days for up to 6 cycles,followed by maintenance treatment with capecitabine and *** main endpoint of the trial was progression-free survival(PFS).The median follow-up was 19.5 *** PFS was 14.8 months(95%CI,11.6-18.0)for the immunotherapy group compared with 9.9 months(8.0-11.8)for the control group(hazard ratio[HR],0.60[95%CI,0.40-0.88];p=0.009).Median overall survival(OS)was not reached for the immunotherapy group and 25.6 months(95%CI,18.3-32.8)for the control group(HR,0.57[95%CI,0.33-0.98];p=0.043).Grade 3 or higher AEs occurred in 20.0%of patients in the immunotherapy group and 23.5%in the control groups,with no toxicity-associated deaths *** addition of PD1-T cells to first-line XELOX plus bevacizumab demonstrates significant clinical improvement of PFS and OS with well tolerability in patients with previously untreated mCRC.

关键词： PD1 immunotherapy bevacizumab

Global stabilization control of stochastic quantum systems

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Science China(Information Sciences) 2016年第11期59卷 208-219页

作者： shuang CONG Jie wen Sen KUANG Fangfang MENG School of Information and Science Technology University of Science and Technology of China Department of Electronic Information and Electrical Engineering Hefei University

The global stabilization control of arbitrary eigenstates for finite dimensional stochastic quantum systems with non-diagonal free Hamiltonian and non-regular measurement operator is studied in this *** propose a switching feedback control law, in which a constant control is used to steer the system state to a convergence domain, and another control law designed based on Lyapunov stability theorem, is used to attract the states in the convergence domain to the desired target state. The convergence to an arbitrary target eigenstate from any initial state is strictly proved. Moreover, numerical simulation experiments on a three-dimensional stochastic quantum system are implemented to demonstrate the effectiveness of the proposed control.

关键词： eigenstate stochastic quantum systems global stabilization switching control Lyapunov stability theorem

Small-Scale Self-Focusing of Intense Laser Beams In the Presence of Vector Effect

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Chinese Physics Letters 2000年第10期17卷 731-733页

作者： wen shuang-Chun FAN Dian-yuan National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

We extend Bespalov-Talanov (B-T) theory on small-scale self-focusing (SSSF) to include vector effect of a very narrow intense laser beam with application of the vector self-focusing model. The gain spectrum for perturbations is obtained by using the standard linear instability analysis. It is shown that the influence on SSSF of vector effect is closely related to the beam width. For a very narrow beam, the role played by vector effect becomes significant, it reduces the fastest growing frequency and the maximum growth rate, and shortens the frequency range for perturbation growing, and thus deviates the gain spectrum from that of B-T theory.

关键词： Focus Small Presence