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Research Characteristics of Thermal Comfort of Urban Block Landscape Based on Knowledge Graph Analysis

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Journal of Landscape Research 2024年第2期16卷 42-46,50页

作者： feng Shutong PENG Li MA Minghao WANG zhihao CONG Jing North China University of Technology Beijing 100144China

The landscape environment of urban blocks plays a significant role in improving the comfort of urban thermal environment and promoting green and high-quality development.The 342 papers related to the research on the impact of urban block landscape environment on thermal comfort in China,collected by CNKI(China National Knowledge Infrastructure)from 2002 to 2022,are used as the research object.Through bibliometric statistical analysis,LLR algorithm,and cluster analysis,the current research status of the impact of urban block landscape environment on thermal comfort in China is analyzed and processed,and its external characteristics are identified.Using the information visualization software CiteSpace,the research topics in the field of the impact of urban block landscape environment on thermal comfort are presented in the form of knowledge graphs.Through co-occurrence analysis of keywords and trend of word frequency changes,the development trends of research hotspots and cutting-edge fields of the impact of urban block landscape environment on thermal comfort are determined,hoping to provide reference for future research in this field.

关键词： Urban block landscape environment Thermal comfort CiteSpace visualization analysis Research hotspots Research frontiers

Improving error-correcting capability in DNA digital storage via soft-decision decoding

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National Science Review 2024年第2期11卷 135-144页

作者：丁璐璐伍世刚候志浩李阿伦许亚苹冯虎潘玮华阮珏 Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural Sciences Guangdong Provincial Key Laboratory of Plant Molecular Breeding State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesSouth China Agricultural University

Error-correcting codes(ECCs) employed in the state-of-the-art DNA digital storage(DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon(RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, Pac Bio and Oxford Nanopore Technology(ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses ‘state-of-the-art' DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs' decoding algorithms.

关键词： DNA digital storage (DDS) error-correcting code (ECC) soft-decision decoding error-correcting capability storage volume

基于三角级数解的钢-混凝土组合梁弹性弯曲变形计算方法

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建筑结构学报 2024年第5期45卷 253-261页

作者：叶华文蒋成川黄澳冯治皓叶杨帆周渝西南交通大学土木工程学院四川成都610031

目前针对考虑界面滑移效应的钢-混凝土组合梁的弯曲变形计算公式缺乏广泛适应性,不便于组合梁结构设计。为此,采用三角级数构造组合梁弹性弯曲变形和界面滑移的位移函数,根据最小势能原理和变分法,推导了简支组合梁在不同荷载类型下的... 详细信息

目前针对考虑界面滑移效应的钢-混凝土组合梁的弯曲变形计算公式缺乏广泛适应性,不便于组合梁结构设计。为此,采用三角级数构造组合梁弹性弯曲变形和界面滑移的位移函数,根据最小势能原理和变分法,推导了简支组合梁在不同荷载类型下的弹性弯曲变形和界面滑移的计算公式,进而得到考虑滑移效应的组合梁抗弯刚度和界面滑移值的统一显式解。通过与大量已有文献中的试验值和既有计算方法比较,验证了其有效性和准确性。结果表明:根据三角级数解推导出的钢-混凝土组合梁弯曲刚度计算公式简洁直观,物理意义明确,结果可靠,所提出的方法适用于精确计算正常使用状态下组合梁弯曲变形。

关键词：钢-混凝土组合梁界面滑移弯曲变形三角级数解统一计算公式

Nb含量对Al_(0.3)CoCrFeNi高熵合金组织与性能的影响

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稀有金属 2024年第3期48卷 336-344页

作者：赵志豪黄正华陶平均陈峰闫志巧广东工业大学材料与能源学院广东广州510006 广东省科学院新材料研究所广东省金属强韧化技术与应用重点实验室粤港轻合金先进制造技术联合研发中心广东广州510650

采用真空电弧炉制备了Al_(0.3)CoCrFeNiNb_(x)(x为摩尔比,x=0,0.1,0.3,0.5,0.7,1.0)高熵合金棒材,用X射线衍射(XRD)、光学显微镜(OM)、扫描电镜(SEM)、能谱仪(EDS)、显微维氏硬度计和万能试验机对合金的微观组织和性能进行了研究。结果... 详细信息

采用真空电弧炉制备了Al_(0.3)CoCrFeNiNb_(x)(x为摩尔比,x=0,0.1,0.3,0.5,0.7,1.0)高熵合金棒材,用X射线衍射(XRD)、光学显微镜(OM)、扫描电镜(SEM)、能谱仪(EDS)、显微维氏硬度计和万能试验机对合金的微观组织和性能进行了研究。结果表明,Al_(0.3)CoCrFeNi合金的微观组织为单相面心立方(fcc);添加Nb后,合金由fcc相和Laves相组成,并随着Nb含量的增加,Laves相体积分数逐渐增多;至Al_(0.3)CoCrFeNiNb_(1.0)时,基体相从fcc相变为Laves相。Al_(0.3)CoCrFeNiNbx合金组织随Nb含量变化经历了亚共晶到过共晶的转变,同时衍射峰(111)fcc先向小角度移动后向大角度移动,晶格常数先增大后减小。Nb元素的增加可以有效提高Al_(0.3)CoCrFeNiNb_(x)合金的强度和硬度,硬度呈近似线性增加,从Al_(0.3)CoCrFeNi合金的HV152提高至Al_(0.3)CoCrFeNiNb_(1.0)合金的HV 745,提高了390%;Al_(0.3)CoCrFeNi合金和Al_(0.3)CoCrFeNiNb_(0.1)合金呈现出优异的压缩塑性(不断裂);随着Nb含量的继续增加,Al_(0.3)CoCrFeNiNb_(x)合金的抗压强度先提高后降低,而塑性降低。Al_(0.3)CoCrFeNiNb_(0.5)合金具有最优的综合力学性能,其抗压强度和维氏硬度分别为2397 MPa和HV 613。

关键词：高熵合金 Nb合金化微观组织力学性能

马氏体时效钢激光选区熔化成形过程介观尺度数值模拟

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机械工程学报 2024年第3期60卷 282-295页

作者：宋军唐倩罗智超冯琪翔聂云飞任治好重庆大学机械与运载工程学院重庆400044 华中科技大学材料成形与模具技术全国重点实验室武汉430074 重庆邮电大学先进制造工程学院重庆400065

激光选区熔化(Selective laser melting,SLM)成形过程涉及多种发生于介观尺度下的物理现象,采用试验方法难以揭示物理现象复杂的形成规律。以18Ni-300马氏体时效钢为SLM成形材料,采用离散元法与有限体积法建立了SLM成形介观尺度热流耦... 详细信息

激光选区熔化(Selective laser melting,SLM)成形过程涉及多种发生于介观尺度下的物理现象,采用试验方法难以揭示物理现象复杂的形成规律。以18Ni-300马氏体时效钢为SLM成形材料,采用离散元法与有限体积法建立了SLM成形介观尺度热流耦合数值模型,并结合熔道成形试验验证模型的正确性。结合数值模拟揭示激光功率从60 W增加至270 W时单道SLM成形熔道形貌、熔池尺寸与温度、传热机制等熔池行为的基本特征;研究在0.2 J/mm、0.3 J/mm和0.45 J/mm线能量密度下不同激光功率和扫描速度组合对熔道形貌、熔池尺寸与传热机制的影响规律;结合熔道搭接理论模型计算激光功率180 W和扫描速度600 mm/s组合下无搭接缺陷的扫描间距理论临界条件约为83μm,并研究80μm、100μm和120μm扫描间距下多道多层SLM成形熔道搭接行为和演变规律。该模型可用于筛选工艺参数区间,提高工艺优化效率,为单层/多层成形的工艺试验提供指导。

关键词：激光选区熔化马氏体时效钢数值模拟熔池缺陷

模块化变电站辅助用房钢框架结构侧向静力性能研究

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合肥工业大学学报（自然科学版） 2024年第4期47卷 562-569页

作者：郑跃曾志豪冯玉龙中国能源建设集团安徽省电力设计院有限公司安徽合肥230601 合肥工业大学土木与水利工程学院安徽合肥230009

文章针对某变电站工程中单层模块化变电站辅助用房钢框架结构的侧向静力性能进行研究,该辅助用房模块单元与基础之间采用地脚螺栓底板连接,模块单元之间采用翼缘高强螺栓和腹板对穿螺栓进行连接,施工简便且具有很好的施工空间;通过ABAQU... 详细信息

文章针对某变电站工程中单层模块化变电站辅助用房钢框架结构的侧向静力性能进行研究,该辅助用房模块单元与基础之间采用地脚螺栓底板连接,模块单元之间采用翼缘高强螺栓和腹板对穿螺栓进行连接,施工简便且具有很好的施工空间;通过ABAQUS软件对模块化变电站辅助用房钢框架结构进行非线性推覆分析,考察结构及其节点的静力性能,给出一些连接构造的性能提升措施,可为类似工程提供参考。

关键词：变电站模块化辅助用房连接节点有限元模拟静力性能连接构造优化

Hot deformation behavior and the processing map of Zr–1.0Be alloy in single α phase

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Progress in Natural Science:Materials International 2015年第5期25卷 496-502页

作者： zhihao feng Xiaojun Jiang Yunkai Zhou Chaoqun Xia Xinyu Zhang Mingzhen Ma Riping Liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University

The hot deformation behavior,hot workability and dynamic recrystallization evolution of Zr-1.0(wt%) Be alloy in single a phase were investigated by conducting hot compression tests.The strain rates ranging from 10sto 10° sand testing temperatures varying from 650 ℃to 850℃ were used.Flow stress was found to increase with increasing strain rate and decrease with the increment of the deformation temperature.A constitutive equation of flow behavior was established to describe the dependence of flow stress on strain rate and deformation temperature.The activation energy for deformation of Zr-1.0Be alloy was determined to be Q= 301 kJ/mol.The processing map of Zr-1.0Be alloy was constructed at strain rates ranging from 10sto 10° sand deformation temperatures varying from 650 ℃ to 850 ℃ at the true strain of 0.7.A processing map was used to identify the best domains of thermal processing,including a domain at a temperature of 650 ℃ and strain rate of 10sas well as another domain at deformation temperatures ranging from 800 ℃ to 850 ℃ and strain rates varying from 10s~-to 10s.Microscopic analysis of Zr-l.OBe alloy showed that the flow instability and kink were very obvious at low temperatures and high strain rates.At high temperatures and low strain rates,the dynamic recrystallization became the main softening mechanism during hot working.

关键词： Zr alloy Hot deformation Constitutive equation Microstructure Dynamic recrystallization

Thermal behavior of Mongolian low-rank coals during pyrolysis

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Carbon Resources Conversion 2021年第1期4卷 19-27页

作者： Ariunaa Alyeksandr Zongqing Bai Jin Bai Narangerel Janchig Purevsuren Barnasan zhihao feng Ranran Hou Chong He Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar 13330Mongolia State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001PR China University of Chinese Academy of Sciences Beijing 100049PR China

Low temperature pyrolysis behavior of four low-rank coals from the biggest deposits of Mongolia were studied using a fixed-bed reactor and Gray-King retort.The coal samples and resultant chars were analyzed using Fourier transform infrared spectroscopy(FTIR),^(13)C nuclear magnetic resonance(^(13)C NMR)to explore the structure changes and thermogravimetric analyzer coupled with mass spectrometry(TG-MS)was used to investigate the pyrolysis reactivity of coal during thermal decomposition process.The results showed that the aliphatic structure in coal was significantly reduced and the carboxyl groups almost completely decomposed during pyrolysis process at 600℃.The tar yield of Gray-king test is higher than that obtained from the fixed-bed reactor.The gaseous evolution measured by TG-MS during pyrolysis showed that the maximum peaks of evolution of CH_(4),H_(2),C_(2)H_(2),C_(2)H_(5),CO,and CO_(2) gases were well corresponded to the maximum rate of weight loss in the range 428-445℃.

关键词： Mongolian low-rank coal Lignite Subbituminous coal Pyrolysis Thermal behavior

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基于时间干涉的小鼠运动行为调控研究

生物医学工程学杂志 2024年第2期41卷 342-350页

作者：朱浩然槐瑞托张平丘汪慧杨俊卿殷涛于志豪邵峰山东科技大学电气与自动化工程学院山东青岛266510 山东科技大学储能技术学院山东青岛266510 青岛今墨堂生物技术有限公司山东青岛266510

时间干涉(TI)作为一种新的神经调控技术可以应用于非侵入性深部脑刺激。为了验证它在动物运动行为调控中的有效性,本文使用TI方法将包络电场聚焦到小鼠脑深部的丘脑腹后外侧核(VPL)调控左、右转运动行为。通过有限元方法分析TI在小鼠VP... 详细信息

时间干涉(TI)作为一种新的神经调控技术可以应用于非侵入性深部脑刺激。为了验证它在动物运动行为调控中的有效性,本文使用TI方法将包络电场聚焦到小鼠脑深部的丘脑腹后外侧核(VPL)调控左、右转运动行为。通过有限元方法分析TI在小鼠VPL的聚焦性,利用数值计算获得聚焦面积和体积,采用刺激器产生TI电流对小鼠VPL进行刺激,验证TI刺激方法的有效性,进一步通过c-Fos免疫荧光实验确定聚焦位置的准确性。结果表明,通过调整电极位置,当刺激电流达到800μA时,TI刺激产生的电场能够聚焦到VPL核团;小鼠能够根据刺激位置进行相应的左、右转;刺激后VPL核团c-Fos阳性细胞标记明显增加。本研究证实了TI在动物运动行为调控中的可行性,为动物机器人提供了一种对脑组织无创的刺激方法。

关键词：时间干涉行为调控丘脑腹后外侧核刺激电流