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Electrical characteristics of a fractional-order 3×n Fan network

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Communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： zhi-Zhong tan Xin Wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(L,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory

Compact magneto-optical traps using planar optics

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Chinese Physics B 2024年第9期33卷 93-108页

作者： zhi tan Bo Lu Chengyin Han Chaohong Lee Institute of Quantum Precision Measurement State Key Laboratory of Radio Frequency Heterogeneous IntegrationCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen 518045China

Magneto-optical traps (MOTs) composed of magnetic fields and light fields have been widely utilized to cool andconfine microscopic particles. Practical technology applications require miniaturized MOTs. The advancement of planaroptics has promoted the development of compact MOTs. In this article, we review the development of compact MOTs basedon planar optics. First, we introduce the standardMOTs. We then introduce the gratingMOTs with micron structures, whichhave been used to build cold atomic clocks, cold atomic interferometers, and ultra-cold sources. Further, we introducethe integrated MOTs based on nano-scale metasurfaces. These new compact MOTs greatly reduce volume and powerconsumption, and provide new opportunities for fundamental research and practical applications.

关键词： magneto-optical trap (MOT) planar optics grating MOT metasurface MOT

A novel encoding mechanism for particle physics

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Nuclear Science and Techniques 2024年第8期35卷 153-166页

作者： zhi‑Guang tan Sheng‑Jie Wang You‑Neng Guo Hua Zheng Aldo Bonasera School of Electronic Information and Electrical Engineering Changsha UniversityChangsha 410003China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFN95123 CataniaItaly

This study proposes a novel particle encoding mechanism that seamlessly incorporates the quantum properties of particles,with a specific emphasis on constituent *** primary objective of this mechanism is to facilitate the digital registration and identification of a wide range of particle *** design ensures easy integration with different event generators and digital simulations commonly used in high-energy ***,this innovative framework can be easily expanded to encode complex multi-quark states comprising up to nine valence quarks and accommodating an angular momentum of up to 99/*** versatility and scalability make it a valuable tool.

关键词： Multi-quark state Encoding mechanism Constituent quark Particle physics

Analysis of cancer-specific survival in patients with metastatic colorectal cancer: A evidence-based medicine study

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1791-1802页

作者： Yin-Jie Zhou zhi-E tan Wei-Da Zhuang Xin-Hua Xu Department of Oncology The First College of Clinical Medical ScienceChina Three Gorges University&Yichang Central People's HospitalYichang 443000Hubei ProvinceChina Department of Nuclear Medicine The First College of Clinical Medical ScienceChina Three Gorges University&Yichang Central People's HospitalYichang 443000Hubei ProvinceChina Department of Athe and Intestinal Surgery Cancer Hospital of The Chinese Academy of Medical SciencesBeijing 100021China

BACKGROUND Metastatic colorectal cancer(mCRC)is a common malignancy whose treatment has been a clinical ***-specific survival(CSS)plays a crucial role in assessing patient prognosis and treatment ***,there is still li-mited research on the factors affecting CSS in mCRC patients and their *** To predict CSS,we developed a new nomogram model and risk grading system to classify risk levels in patients with *** Data were extracted from the United States Surveillance,Epidemiology,and End Results database from 2018 to *** eligible patients were randomly divided into a training cohort and a validation *** Cox proportional hazards model was used to investigate the independent risk factors for CSS.A new nomogram model was developed to predict CSS and was evaluated through internal and external *** A multivariate Cox proportional risk model was used to identify independent risk factors for ***,new CSS columns were developed based on these *** consistency index(C-index)of the histogram was 0.718(95%CI:0.712-0.725),and that of the validation cohort was 0.722(95%CI:0.711-0.732),indicating good discrimination ability and better performance than tumor-node-metastasis staging(C-index:0.712-0.732).For the training set,0.533,95%CI:0.525-0.540;for the verification set,0.524,95%CI:*** calibration map and clinical decision curve showed good agreement and good potential clinical *** risk grading system divided all patients into three groups,and the Kaplan-Meier curve showed good stratification and differentiation of CSS between different *** median CSS times in the low-risk,medium-risk,and high-risk groups were 36 months(95%CI:34.987-37.013),18 months(95%CI:17.273-18.727),and 5 months(95%CI:4.503-5.497),*** Our study developed a new nomogram model to predict CSS in patients with synchronous *** addition,the risk-grading system helps to accurately ass

关键词： Colorectal tumor Surveillance epidemiology and end results database Nomogram analysis Survival prognosis Retrospective study

Effectively improved piezoelectricityyinhigh-temperature Arrhenius CBT ceramics by modifying potential energy profile and spontaneous polarization

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Journal of Advanced Ceramics 2024年第8期13卷 1143-1152页

作者： Jingwen Xi Linlin Liu Hongwei Qiao Jiacheng Luo Xin Su Xin Zhao Yugen Xu Hao Chen zhi tan Jianguo Zhu Nuclear Power Institution of China Chengdu 610213China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China

Enhancing the piezoelectricity of CaBi_(4)Ti_(4)O_(15)(CBT)ceramics is crucial for improving their application potential in high-temperature piezoelectric ***,we propose a strategy involving the introduction of larger Na/Bi ions at the A-site,effectively inhibiting the tilt of oxygen octahedra and flattening the potential energy *** flattening enhances the variation in polarization under external ***,substituting Nb/Mn at the B-site increases the deviation between positive and negative ionic centers,leading to stronger spontaneous polarization,while the induced defect dipoles restrict oxygen vacancy migration and increase the direct current resistivity(ρ_(dc)).The flattened potential energy profile and increased spontaneous polarization significantly enhance the overall performance of cBT ceramics,with the piezoelectric constant(d_(33))reaching 25 pC/N when the Curie temperature(Tc)=752℃.Piezoresponse force microscopy(PFM)and transmission electron microscopy(TEM)revealed submicron-long rectangular domains and nanoscale domains in the modified composition,indicating a high density of domain *** study presents an effective approach for enhancing the piezoelectric properties of bismuth layered-structured ferroelectrics(BLSFs),thereby improving the application potential of BLSFsathightemperatures.

关键词： piezoelectricity bismuth layered-structured ferroelectrics(BLSFs) potential energy profile spontaneous polarization high temperatures

Enhanced electrical properties and Vickers hardness of calcium bismuth niobate ceramics by W/Co substituted at B-site

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Journal of Advanced Dielectrics 2024年第4期14卷 92-103页

作者： Fei Wang Jia Yang Qing Yang Ning Chen Xinji Yang Mingyue Mo Jie Xing zhi tan Zhongqing Tian Fancheng Meng Yuheng Guo Huixing Lin Jianguo Zhu College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054P.R.China College of Materials Science and Engineering Sichuan UniversityChengdu 610064P.R.China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730P.R.China Key Laboratory of Inorganic Functional Material and Device Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899P.R.China

Calcium bismuth niobate(CBN)ceramic,as a core element of high-temperature piezoelectric sensors,has attracted widespread attention due to its high Curie temperature within the class of Aurivillius ***,CBN usually faces two *** piezoelectric constant and low *** this work,CBN-based ceramics with donor–acceptor ions(W/Co)co-substituted at B-site were prepared by solid-state reaction method,and structure–property relationship of ceramics was studied in ***-substitution of W/Co ions effectively improved the electrical property and hardness of CBN ***_(2)Nb_(1.91)(W_(2/3)Co_(1/3)T_(0.09)O_(9))exhibits enhanced electrical and mechanical properties including high resistivity of-10^(7)Ω·cm at 500℃,piezoelectric constant of-15.3 pC/N and hardness value of-3.57 *** values are two orders of magnitude,over two times,and 1.36 times higher than those of pure CBN ceramic,*** work provides a reference for exploring other bismuth-layered structural ceramics.

关键词： Calcium bismuth niobate ceramics donor and acceptor ions B-site electrical properties Vickers hardness

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SMA碟簧群的循环受压性能及简化模型

工程力学 2024年第7期41卷 163-175页

作者：赵秋红孙泽旺谭志伦天津大学建筑工程学院天津300350 滨海土木工程结构与安全教育部重点试验室(天津大学) 天津300350 天津市政工程设计研究总院有限公司天津300329

该研究提出将多个形状记忆合金(SMA)碟簧片并联排列形成碟簧组,然后在碟簧组间加入垫片分隔、串联排列形成碟簧群,以提供更高的承载力及变形能力。采用有限元软件ABAQUS建立了一系列SMA碟簧群的三维精细化有限元模型,并进行非线性循环... 详细信息

该研究提出将多个形状记忆合金(SMA)碟簧片并联排列形成碟簧组,然后在碟簧组间加入垫片分隔、串联排列形成碟簧群,以提供更高的承载力及变形能力。采用有限元软件ABAQUS建立了一系列SMA碟簧群的三维精细化有限元模型,并进行非线性循环受压分析。结果表明:与钢碟簧的“三角形”荷载-位移曲线相比,SMA碟簧群的荷载-位移曲线呈现鲜明的“旗帜形”特性,具有明显的正向及反向转变平台。随着碟簧片数的增加,碟簧组的总可恢复变形量基本不变,极限承载力及割线刚度近似成比例增加,而随着碟簧组数的增加,碟簧群的总可恢复变形量增加,极限承载力不变,割线刚度近似成比例降低。因此,可根据碟簧群总极限承载力及变形能力的需要,灵活调整碟簧片及碟簧组的数量及布置方式。碟簧组的各层碟簧片由于边界条件不同,应力分布存在明显差异,而变形量亦呈现两端大中间小的哑铃形分布模式,其中加载端碟簧片变形量最大,若超过极限变形量可能发生翻转失效,值得注意。提出了SMA碟簧群的简化模型,通过简化及精细模型的非线性循环受压分析,发现该简化模型的循环受压荷载-位移曲线与精细模型吻合良好,而计算效率提高约38倍。将SMA碟簧群应用于自复位NZ梁柱节点中,并对自复位钢框架进行了验证性的滞回分析。结果表明:采用SMA碟簧群的自复位钢框架最大侧移为4%时可完全复位,且二次刚度相比采用预应力钢绞线的传统自复位钢框架提高近100%,极限承载力提高70%。

关键词： SMA碟簧碟簧群循环受压性能简化模型自复位钢框架

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基于神经切线核的学件RKME规约

计算机学报 2024年第6期47卷 1232-1243页

作者：谭志豪史浩宇陈梓轩姜远南京大学计算机软件新技术国家重点实验室南京210023

当前机器学习技术已经在大量领域得到广泛应用,然而仍面临许多亟待解决的问题:依赖大量的训练数据和训练技巧、难以适应环境变化、数据隐私/所有权的保护、灾难性遗忘等等.最近,学件范式使得上述问题同时得到系统性地解决成为可能.在该... 详细信息

当前机器学习技术已经在大量领域得到广泛应用,然而仍面临许多亟待解决的问题:依赖大量的训练数据和训练技巧、难以适应环境变化、数据隐私/所有权的保护、灾难性遗忘等等.最近,学件范式使得上述问题同时得到系统性地解决成为可能.在该范式下,用户面临新的机器学习任务时可以通过学件基座系统方便地复用他人的结果,而不必从头开始.学件范式的核心在于规约,规约使得学件基座系统在不接触原始数据的情况下,可以根据用户的需求快速识别出对用户任务有帮助的学件.近期研究均通过缩略核均值嵌入(Reduced Kernel Mean Embedding,RKME)为模型构造规约,并通过构建学件原型系统验证了范式的有效性.在实际中,学件基座系统中往往包含在各种领域任务、数据类型上构建的机器学习模型,而传统的RKME规约面临维度灾难的问题,难以适用于高维数据,例如图像场景.为了拓展RKME规约的适用范围,本文引入神经切线核进行RKME规约构造.为提升方法的高效性,本文进一步通过神经网络高斯过程与随机特征近似,快速为各种模型生成RKME规约.最后,本文在真实数据构建的销量预测、图像分类场景的学件基座系统中进行大量实验验证了所提出方法的有效性和高效性,所提出方法相比于传统RKME规约查搜准确率显著提升近9%,且实验结果表明改进后的规约在图像任务上具有良好的隐私保护性质.代码见:.

关键词：学件学件基座系统规约神经切线核缩略核均值嵌入

耐高温树脂基复合材料研究进展及其在航空航天领域的应用

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宇航材料工艺 2024年第2期54卷 18-28页

作者：张涵其谭指彭飞王兵哈尔滨工业大学特种环境复合材料技术国家级重点实验室哈尔滨150001 北京宇航系统工程研究所北京100076

耐高温树脂基复合材料具有低密度、高比强度、高比模量、抗疲劳、耐腐蚀、可设计性强等优点。因其在结构轻量化中的巨大应用潜力,在航空航天领域广受关注。本文重点介绍了双马来酰亚胺、聚酰亚胺和邻苯二甲腈三种耐高温树脂及其复合材料... 详细信息

耐高温树脂基复合材料具有低密度、高比强度、高比模量、抗疲劳、耐腐蚀、可设计性强等优点。因其在结构轻量化中的巨大应用潜力,在航空航天领域广受关注。本文重点介绍了双马来酰亚胺、聚酰亚胺和邻苯二甲腈三种耐高温树脂及其复合材料,并对其树脂基体的历史发展脉络、复合材料成型工艺与力学性能的研究现状,以及在航空航天领域的应用进行了综述。最后,通过提炼对比三者在工艺性、力学性能上的特点和工程上的典型应用场景,拟为航空航天领域中的材料选择提供参考。

关键词：树脂基复合材料耐热性力学性能航空航天应用