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Crashworthiness of innovative hexagonal honeycomb-like structures subjected to out-of-plane compression

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Journal of Central South University 2020年第2期27卷 621-628页

作者： WANG Zhong-gang shi chong DING San-san LIANG Xi-feng CRRC Qingdao Sifang Co. Ltd.Qingdao 266111China Key Laboratory of Traffic Safety on Track(Ministry of Education) School of Traffic and Transportation EngineeringCentral South UniversityChangsha 410075China

Seeking for innovative structures with higher mechanical performance is a continuous target in railway vehicle crashworthiness *** the present study,three types of hexagonal reinforced honeycomb-like structures were developed and analyzed subjected to out-of-plane compression,namely triangular honeycomb(TH),double honeycomb(DH)and full inside honeycomb(FH).Theoretical formulas of average force and specific energy absorption(SEA)were constructed based on the energy minimization *** validate,corresponding numerical simulations were carried out by explicit finite element *** agreement has been observed between *** results show that all these honeycomb-like structures maintain the same collapsed stages as conventional honeycomb;cell reinforcement can significantly promote the performance,both in the average force and SEA;full inside honeycomb performs better than the general,triangular and double schemes in average force;meanwhile,its SEA is close to that of double scheme;toroidal surface can dissipate higher plastic energy,so more toroidal surfaces should be considered in design of thin-walled *** achievements pave a way for designing high-performance cellular energy absorption devices.

关键词： honeycomb-like structure crashworthiness basic fold element structural reinforcement

School Debit Transaction Using Fingerprint Recognition System

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Artificial Intelligence Advances 2019年第2期1卷 24-37页

作者： Wai Kit Wong Thu Soe Min shi Enn chong Faculty of Engineering and Technology Multimedia University(MMU)Jalan Ayer Keroh LamaMelaka75450Malaysia

This paper proposed a fingerprint based school debit transaction system using minutiae matching biometric *** biometric cashless transaction system intensely shortens the luncheon line traffic and labour force compared to conventional cash payment ***,contrast with card cashless transaction system,fingerprint cashless transaction system with benefit that user need not carry additional identification object and remember lengthy *** implementation of this cashless transaction system provides a more organize,reliable and efficient way to operate the school debit transaction system.

关键词： Fingerprint recognition Biometric Authentication Image processing

The Interference Analysis and Evaluation of DME to BeiDou-3/B2a

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The Interference Analysis and Evaluation of DME to BeiDou-3/...

Encapsulated three-dimensional bioprinted structure seeded with urothelial cells:a new construction technique for tissue-engineered urinary tract patch

第十四届中国卫星导航年会

作者： Jian-ming Zhang Fei Xu shi-chong Li The 20th Research Institute of China Electronics Technology Group Corporation

DME is a kind of important equipment for air route navigation and landing *** has high transmitting power,a large number of installations,a wide range of signal coverage region,and also works at same frequency band with BeiDou-3/B2a *** will interfere the weak satellite navigation *** order not to affect the signal capture,improve BeiDou receiver carrier tracking and code tracking accuracy,and reduce BER(Bit error rata),it is especially necessary to carry out the analysis and evaluation of DME to BeiDou-3/B2a signal interference and suppression measures ***,through the analysis of characteristics of DME and BeiDou-3/B2a signal,based on RTCA/DO-292 standard about radio signal on GPS/L5,Galileo/E5a interference impact analysis,proposed DME on BeiDou-3/B2a signal interference effective carrier-to-noise ratio degradation evaluation ideas and analysis *** on the effective carrier-to-noise degradation algorithm model,DME to BeiDou-3/B2a signal interference evaluation was carried out for two hundred and five DME ground beacons co-located with VOR(Very-high-frequency Omnidirectional Range) for air route navigation in *** interference evaluation method of DME to BeiDou-3/B2a in the paper provides technical guarantee for improving accuracy,availability,continuity and integrity of BeiDou navigation system,carrying out research on interference suppression measures and BeiDou system application.

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Chinese Medical Journal 2020年第4期133卷 424-434页

作者： Yi-Peng Jin chong shi Yuan-Yi Wu Ji-Lei Sun Jiang-Ping Gao Yong Yang Department of Urology Sixth Medical Center of Chinese People's Liberation Army General HospitalBeijing 100048China The First Center of Department of Hepatobiliary Surgery Fifth Medical Center of Chinese People's Liberation Army General HospitalBeijing 100039China Department of Urology Fourth Medical Center of Chinese People's Liberation Army General HospitalBeijing 100048China Department of Urology First Medical Center of Chinese People's Liberation Army General HospitalBeijing 100853China

Background:Traditional tissue engineering methods to fabricate urinary tract patch have some drawbacks such as compromised cell viability and uneven cell distribution within *** this study,we combined three-dimensional(3D)bioprinting and tissue engineering method to form a tissue-engineered urinary tract patch,which could be employed for the application on Beagles urinary tract defect mode to verify its effectiveness on urinary tract ***:Human adipose-derived stem cells(hADSCs)were dropped into smooth muscle differentiation medium to generate induced microtissues(ID-MTs),flow cytometry was utilized to detect the positive percentage for CD44,CD105,CD45,and CD34 of *** of vascular endothelial growth factor A(VEGFA)and tumor necrosis factor-stimulated gene-6(TSG-6)in hADSCs and MTs were identified by Western *** the ID-MTs were employed for 3D *** bioprinted structure was encapsulated by transplantation into the subcutaneous tissue of nude mice for 1 *** retrieval of the encapsulated structure,hematoxylin and eosin and Masson’s trichrome staining were performed to demonstrate the morphology and reveal collagen and smooth muscle fibers,integral optical density(IOD)and area of interest were calculated for further semiquantitative *** double staining of CD31 andα-smooth muscle actin(α-SMA)were used to reveal vascularization of the encapsulated *** was performed to evaluate the expression of interleukin-2(IL-2),α-SMA,and smoothelin of the MTs in the implanted ***,the encapsulated structure was seeded with human urothelial *** staining of cytokeratins AE1/AE3 was applied to inspect the morphology of seeded encapsulated ***:The semi-quantitative assay showed that the relative protein expression of VEGFA was 0.355±0.038 in the hADSCs vs.0.649±0.150 in the MTs(t=3.291,P=0.030),while TSG-6 expression was 0.492±

关键词： Human adipose-derived stem cells Urinary tract patch Microtissues Tissue engineering Three-dimensional bioprinting

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思维的计算特征与计算的思维属性

计算机科学 2014年第2期41卷 11-14页

作者：史文崇河北科技师范学院数学与信息技术学院

研究了计算思维的本质和培养计算思维应注意的问题。从分析国际学术界的一些观点出发,认为计算思维是一种学科思维,也是一种计算哲学。指出理解计算思维的关键是把握思维的计算学科特征和计算的思维属性。提出了计算思维的标志性概念的... 详细信息

研究了计算思维的本质和培养计算思维应注意的问题。从分析国际学术界的一些观点出发,认为计算思维是一种学科思维,也是一种计算哲学。指出理解计算思维的关键是把握思维的计算学科特征和计算的思维属性。提出了计算思维的标志性概念的筛选原则,并由此给出了一些标志性概念,认为计算思维就蕴含在这些概念的共性之中,其典型思想有结构化思想、形式化思想、联动化思想、最优化思想。培养计算思维必须以此为基础。

关键词：计算思维计算学科特征思维属性标志性概念典型思想

联合运用改进的极限平衡法和动态规划法分析边坡稳定性

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水利学报 2007年第10期38卷 1272-1277页

作者：吴海真顾冲时河海大学水利水电工程学院

为了解决边坡关键滑动面全局优化处理问题,将动态规划理论引入基于有限元的改进极限平衡法。与工程上被广泛认可的一般极限平衡法比较表明,本文提出的方法可以获得更好的近似解甚至是整体最优解,关键滑动面更符合工程实际,有效地克服了... 详细信息

为了解决边坡关键滑动面全局优化处理问题,将动态规划理论引入基于有限元的改进极限平衡法。与工程上被广泛认可的一般极限平衡法比较表明,本文提出的方法可以获得更好的近似解甚至是整体最优解,关键滑动面更符合工程实际,有效地克服了传统边坡稳定分析方法的不足;与目前国内外同类方法相比具有明显的优越性,丰富了边坡稳定分析和确定关键滑动面的方法和理论。

关键词：边坡稳定有限元改进的极限平衡法关键滑动面动态规划

护理专业大学生宗教信仰知识、态度和行为调查

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中国实用护理杂志 2013年第23期29卷 56-58页

作者：史崇清武汉科技大学医学院护理系 430065

目的了解护理专业学生宗教信仰的知识、态度和行为现状，为护理专业大学生宗教信仰教育提供科学依据。方法问卷调查武汉市4所本科院校护理专业大学生。结果大部分护理专业学生对宗教信仰相关知识认知程度不高，且与年级、民族、父母信... 详细信息

目的了解护理专业学生宗教信仰的知识、态度和行为现状，为护理专业大学生宗教信仰教育提供科学依据。方法问卷调查武汉市4所本科院校护理专业大学生。结果大部分护理专业学生对宗教信仰相关知识认知程度不高，且与年级、民族、父母信仰宗教与否和家庭居住地等因素有关。大学生对宗教的政策内涵认识模糊。多数学生对宗教与科学的关系认知正确。学校对学生宗教观的教育影响较弱，大学生接触宗教的渠道多样化，网络的作用不可低估。护理专业学生对宗教信仰包括对同学信奉的宗教持理解包容的态度。宗教信仰在护理专业学生中不是信仰的主流。佛教信仰占宗教信仰的首位；大部分学生前往宗教活动场所并非为信仰。结论应直面现实，理性审视，加强社会、学校、家庭和个人的宗教观引导和相关教育建设。

关键词：宗教信仰知识态度行为护理专业大学生

基于复数傅里叶分析的岩土颗粒细观特征识别与随机重构方法

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岩土力学 2016年第10期37卷 2780-2786页

作者：石崇白金州于士彦王伟河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 河海大学岩土工程科学研究所江苏南京210098

岩土细观特征的识别与分析是岩土力学研究的重要内容。基于傅里叶变换原理,将任意岩土颗粒的二维轮廓变换为傅里叶描述符与相位进行分析,建立了基于复数傅里叶分析的细观特征表征与重构方法。通过两组不同颗粒的傅里叶细观特征统计,研... 详细信息

岩土细观特征的识别与分析是岩土力学研究的重要内容。基于傅里叶变换原理,将任意岩土颗粒的二维轮廓变换为傅里叶描述符与相位进行分析,建立了基于复数傅里叶分析的细观特征表征与重构方法。通过两组不同颗粒的傅里叶细观特征统计,研究了不同阶傅里叶描述符与细观特征参量的对应关系。结果表明:-12~0及16~20阶对应的傅里叶描述符决定颗粒的形状;-23^-11及1~15阶对应的傅里叶描述符与颗粒粗糙度密切联系;傅里叶描述符曲线峰值与颗粒的粒径显著线性相关;高阶傅里叶系数与阶数近似呈对数线性关系,低阶系数则由不同颗粒形状决定。采用建立的傅里叶描述符对应关系进行颗粒相似重构研究,发现重构颗粒的外轮廓及傅里叶统计参量与实际颗粒十分接近,且反映颗粒的粗糙度、纹理等细部特征,其成果可用于大量岩土颗粒与力学特性的相关性研究。

关键词：岩土颗粒细观特征复数傅里叶分析随机重构

Gold-catalyzed intermolecular amination of allyl azides with ynamides: Efficient construction of 3-azabicyclo[3.1.0] scaffold

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Chinese Chemical Letters 2025年第2期36卷 384-388页

作者： chong-Yang shi Jian-Xing Gong Zhen Li Chao Shu Long-Wu Ye Qing Sun Bo Zhou Xin-Qi Zhu College of Chemistry and Chemical Engineering Yunnan Normal University Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfacesand College of Chemistry and Chemical EngineeringXiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong University

Gold-catalyzed amination reactions based on azides via α-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules, especially valuable N-heterocycles. However,successful examples of intermolecular generation of α-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides. Herein, we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides, enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex–2-ene derivatives in good to excellent yields with excellent diastereoselectivities. Importantly, this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.

关键词： Alkynes Amination Azides Gold Heterocycles