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Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： Xue-Qing Wang cheng Song Ting Lei Key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

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基于物理模型的曲线保形性重构技术

机械工程学报 2006年第8期42卷 159-163页

作者：唐克伦张湘伟成思源熊汉伟张洪重庆大学资源及环境科学学院广东工业大学机电学院广州510090

实现多种数据的融合是提高反求工程中数据获取的精度和效率的一种有效途径。提出的一种基于物理模型的曲线保形性重构方法,较好地解决了三标测量机的测量数据和视觉信息的融合问题。从材料力学原理出发,提出了曲线歪斜能作为内能,并以... 详细信息

实现多种数据的融合是提高反求工程中数据获取的精度和效率的一种有效途径。提出的一种基于物理模型的曲线保形性重构方法,较好地解决了三标测量机的测量数据和视觉信息的融合问题。从材料力学原理出发,提出了曲线歪斜能作为内能,并以少量精确测量数据点为平衡位置建立曲线的弹性势能作为外能。依据变分原理,采用B样条有限元法,确定曲线变形后的平衡位置。数值模拟表明,利用该方法重构的曲线能够较好地逼近真实曲线。

关键词： B样条有限元法保形性曲线重构

Designing novel adaptive dynamic event-triggered protocols for uncertain multi-agent systems

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Science China(Information Sciences) 2024年第1期67卷 310-311页

作者： Bin cheng Bin HE College of Electronics and Information Engineering Tongji University Frontiers Science Center for Intelligent Autonomous Systems

Multi-agent systems (MASs) have garnered widespread attention and have been investigated by numerous researchers in recent years, primarily due to their broad applications in industry, transportation, agriculture, and astronomy. While studying the cooperative control of MASs, numerous researchers place emphasis on reducing the frequency of communication among neighboring agents.

关键词： Directed graphs

Evaluating quality of motion for unsupervised video object segmentation

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Optoelectronics Letters 2024年第6期20卷 379-384页

作者： cheng Guanjun SONG Huihui Jiangsu Key Laboratory of Big Data Analysis Technology Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment TechnologyNanjing University of Information Science&TechnologyNanjing 210044China12

Current mainstream unsupervised video object segmentation(UVOS) approaches typically incorporate optical flow as motion information to locate the primary objects in coherent video frames. However, they fuse appearance and motion information without evaluating the quality of the optical flow. When poor-quality optical flow is used for the interaction with the appearance information, it introduces significant noise and leads to a decline in overall performance. To alleviate this issue, we first employ a quality evaluation module(QEM) to evaluate the optical flow. Then, we select high-quality optical flow as motion cues to fuse with the appearance information, which can prevent poor-quality optical flow from diverting the network's attention. Moreover, we design an appearance-guided fusion module(AGFM) to better integrate appearance and motion information. Extensive experiments on several widely utilized datasets, including DAVIS-16, FBMS-59, and You Tube-Objects, demonstrate that the proposed method outperforms existing methods.

关键词： Evaluating quality of motion for unsupervised video object segmentation

Towards a blood ecosystem approach to dissect systemic diseases

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Science China(Life Sciences) 2024年第7期67卷 1528-1531页

作者： Hong Wang Tao cheng State Key Laboratory of Experimental Hematology Haihe Laboratory of Cell EcosystemNational Clinical Research Center for Blood DiseasesInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300020China Tianjin Institutes of Health Science Tianjin 301600China

Systemic diseases,in contrast to localized ailments,exert widespread effects and can impact the entire *** of systemic diseases encompass autoimmune disorders,infectious diseases,metabolic disorders,and chronic conditions like *** diseases often entail intricate interactions among diverse organs,tissues,and physiological systems,influenced by a myriad of factors.

关键词： diseases organs autoimmune

Wideband Millimeter Wave Antenna with Cavity Backed Slotted Patch and Magneto-Electric Dipole

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Chinese Journal of Electronics 2024年第5期33卷 1234-1244页

作者： Yang cheng Yuandan DONG School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper proposes a wideband cavity-backed slotted patch antenna, loaded with a magneto-electric（ME）-dipole and fed by a microstrip line, for millimeter wave（mm-Wave） applications. The coupled-feed cavitybacked slotted patch antenna is loaded with the ME-dipole. The slotted patch antenna serves as both a radiator and a ground for the ME-dipole. The combination of the ME-dipole antenna and the slotted patch antenna realizes a –10 dB impedance bandwidth covering over 22.86–44.35 GHz（63.9%）. The pattern of the antenna element remains stable throughout this bandwidth. The proposed broadband antenna unit not only realizes single linearly polarized（LP）radiation but also can be designed for dual-LP radiation. The dual-polarized radiation can be achieved by changing the slot of the patch antenna to a crossed slot and altering the ME-dipole antenna to a dual-polarization form. A 2 × 2 dual-polarized array has been designed, fabricated, and tested. A novel dual-polarized feeding network is *** achieve higher isolation, broadband in-phase feed and differential feed are adopted, respectively. A low-loss single to the differential structure is proposed for differential feeding. The simulated isolation of the array is higher than 40 d *** results show that the dual-polarized 2 × 2 array has an overlapping bandwidth of 52.3%(|S11| < –10 dB and |S21| < –30 dB) with a peak gain of 14 dBi. The proposed antenna, featuring a wide overall bandwidth, low cost,and good radiation performance, is well suited for mm-Wave applications.

关键词： Slot antennas Costs Dipole antennas Patch antennas Magnetoelectric effects Broadband communication Broadband antennas Array antenna Dual-polarized antenna Feeding network Magneto-electric dipole Millimeter-wave (mm-Wave) Patch BROAD-BAND POLARIZED ANTENNA ARRAY PLANAR BALUN

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精密测量仪器在超精密加工实验室中的作用

实验技术与管理 2017年第7期34卷 222-227页

作者：王素娟成思源周春强广东工业大学广东省微纳加工技术与装备重点实验室广东广州510006 广东工业大学广东省创新方法与决策管理系统重点实验室广东广州510006

实验室不仅需要配置高水平的超精密加工装备,还需要相应的精密测量仪器。如何正确而有效地利用加工装备和测量仪器,是超精密加工技术专业本科生和研究生必须掌握的能力。利用白光干涉仪和扫描电子显微镜在超精密加工机理研究中的应用,... 详细信息

实验室不仅需要配置高水平的超精密加工装备,还需要相应的精密测量仪器。如何正确而有效地利用加工装备和测量仪器,是超精密加工技术专业本科生和研究生必须掌握的能力。利用白光干涉仪和扫描电子显微镜在超精密加工机理研究中的应用,分析精密测量仪器在超精密加工实验室中的重要作用,提出一个具体的方案解决目前精密仪器数量少而学生多的实际问题。

关键词：超精密加工精密测量仪器白光干涉仪扫描电镜

Cohomology groups of a new class of Kadison-Singer algebras

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Science China Mathematics 2024年第3期67卷 593-606页

作者： Guangyu An Xing cheng Jun Sheng School of Mathematics and Data Science Shaanxi University of Science and TechnologyXi’an 710021China

Let N be a maximal discrete nest on an infinite-dimensional separable Hilbert space H,ξ=∑^(∞)_(n=1)en/2n be a separating vector for the commutant N',E_(ξ)be the projection from H onto the subspace[Cξ]spanned by the vectorξ,and Q be the projection from K=H⊕H⊕H onto the closed subspace{(η,η,η)^(T):η∈H}.Suppose that L is the projection lattice generated by the projections(E_(ξ) 0 0 0 0 0 0 0 0),{(E 0 0 0 0 0 0 0 0):E∈N},(I 0 0 0 I 0 0 0 0) and *** show that L is a Kadison-Singer lattice with the trivial ***,we prove that every n-th bounded cohomology group H~n(AlgL,B(K))with coefficients in B(K)is trivial for n≥1.

关键词： Kadison-Singer algebra Kadison-Singer lattice derivation cohomology group

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基于特征分解的逆向建模技术研究

现代制造工程 2016年第2期 119-122页

作者：蔡闯成思源杨雪荣广东工业大学机电工程学院广州510006

将组件分析的思想融入已有的建模方法,提出一种基于特征分解的逆向建模方法。将模型分解为规则特征和不规则特征,建立特征的组件关系,并以Geomagic Design Direct软件为平台,结合其特征提取功能拟合特征的实体,通过布尔运算建立完整的... 详细信息

将组件分析的思想融入已有的建模方法,提出一种基于特征分解的逆向建模方法。将模型分解为规则特征和不规则特征,建立特征的组件关系,并以Geomagic Design Direct软件为平台,结合其特征提取功能拟合特征的实体,通过布尔运算建立完整的实体模型。运用特征分解的思路可建立包含原始设计意图的参数化计算机辅助设计(Computer Aided Design,CAD)模型,且建模过程清晰、高效。基于特征分解的逆向建模技术为产品的快速建模和创新设计提供了一种系统的方法。

关键词：组件分析特征分解特征分类逆向建模