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Fatigue Crack Growth in Cold-Rolled and Annealed Polycrystalline Superelastic NiTi Alloys

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Acta Mechanica Solida Sinica 2018年第5期31卷 599-607页

作者： Junyu Chen Hao Yin Guozheng kang Qingping Sun School of Civil Engineering Wuhan University Wuhan 430072 China State Key Laboratory-of Traction Powerl Southwest Jiaotong University Chengdu 610031 China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Kowloon Hong Kong China

The fatigue crack growth in cold-rolled （CR） and annealed （AN） polycrystalline superelastic NiTi shape memory alloys under cyclic stressing are investigated. The fatigue crack growth morphologies of compact tension specimens are recorded. Experimental results show that the main cracks of the AN specimens grow along the original crack plane, while the crack paths of the CR specimens orient at 18° angle to the original horizontal crack plane. The latter is due to the strong anisotropy of elastic modulus and hardness after the cold rolling. Besides, the fatigue crack growth rates of the AN specimens in the regime of △K = 4 MPa√m-9 MPa√m are lower than those of the CR ones. The AN specimens have higher fatigue crack growth resistance than the CR specimens due to the stronger shielding mechanism caused by plastic deformation and reduced anisotropy by annealing.

关键词： Fatigue crack growth NiTi Anisotropy Shielding mechanism

Exploring prognostic potential of long noncoding RNAs in colorectal cancer based on a competing endogenous RNA network

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World Journal of Gastroenterology 2020年第12期26卷 1298-1316页

作者： Zhi-Dong Yang Hui kang Department of Laboratory Medicine The First Affiliated Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

BACKGROUND Colorectal cancer(CRC)is one of the most prevalent tumors ***,long noncoding RNAs(lncRNAs)have been shown to influence tumorigenesis and tumor progression by acting as competing endogenous RNAs(ceRNAs).It is difficult to extract prognostic lncRNAs and useful bioinformation from most ceRNA networks constructed *** To construct a prognostic related ceRNA regulatory network and lncRNA related signature based on risk score in *** RNA transcriptome profile and clinical information of 506 CRC patients were downloaded from the Cancer Genome Atlas database.R packages and Perl program were used for data *** regression analysis was used for prognostic model *** real-time polymerase chain reaction was used to detect the expression of *** A prognostic-related ceRNA network was constructed,including 9 lncRNAs,44 mRNAs,and 30 *** addition,a four-lncRNA model was constructed using multivariate Cox regression analysis,which could be an independent prognostic model in *** risk score for each patient was calculated,and the 506 patients were divided into high and low-risk groups(253 for each group)based on the median risk *** results of the survival analysis showed that patients with a high-risk score had a poor survival ***,the predictive value of the four-lncRNA model was evaluated in *** survival probabilities could be better predicted when combing the risk score and clinical *** Set Enrichment Analysis results verified that a number of cancer-related signaling pathways were enriched with a high-risk score in ***,we validated a novel lncRNA(LINC00488)using quantitative real-time polymerase chain reaction in 22 paired CRC patient tumor tissues compared to adjacent non-tumor *** The four-lncRNA model could give better predictive value for CRC *** understanding of the lncRNA-related ceRNA regulatory mechanism coul

关键词： Colorectal cancer Long noncoding RNA miRNA mRNA Transcription factor Competing endogenous RNA Survival

Advances and challenges in DFT-based energy materials design

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Chinese Physics B 2022年第10期31卷 34-52页

作者： Jun kang Xie Zhang Su-Huai Wei Beijing Computational Science Research Center Beijing 100193China

The growing worldwide energy needs call for developing novel materials for energy *** initio density functional theory(DFT)calculations allow the understanding and prediction of material properties at the atomic scale,thus,play an important role in energy materials *** to the fast progress of computer power and development of calculation methodologies,DFT-based calculations have greatly improved their predictive power,and are now leading to a paradigm shift towards theory-driven materials *** aim of this perspective is to introduce the advances in DFT calculations which accelerate energy materials *** first present state-of-the-art DFT methods for accurate simulation of various key properties of energy *** we show examples of how these advances lead to the discovery of new energy materials for photovoltaic,photocatalytic,thermoelectric,and battery *** challenges and future research directions in computational design of energy materials are highlighted at the end.

关键词： density functional theory materials design energy applications

临床及影像学评价硬化治疗静脉畸形效果研究进展

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中国介入影像与治疗学 2024年第2期21卷 114-117页

作者：康佳佳何昀重庆医科大学附属儿童医院普外新生儿外科、国家儿童健康与疾病临床医学研究中心、儿童发育疾病研究教育部重点实验室、结构性出生缺陷与器官修复重建重庆市重点实验室重庆401122

静脉畸形(VM)为最常见先天性脉管畸形,其临床表现取决于病灶范围及位置,包括疼痛、肿胀、活动受限及出血等;治疗VM方法包括硬化治疗、手术治疗及激光治疗等,硬化为一线治疗方案。目前对于评价硬化治疗VM效果尚未建立统一标准。本文围绕... 详细信息

静脉畸形(VM)为最常见先天性脉管畸形,其临床表现取决于病灶范围及位置,包括疼痛、肿胀、活动受限及出血等;治疗VM方法包括硬化治疗、手术治疗及激光治疗等,硬化为一线治疗方案。目前对于评价硬化治疗VM效果尚未建立统一标准。本文围绕临床及影像学评价硬化治疗静脉畸形效果进展进行综述。

关键词：血管畸形超声检查磁共振成像

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Long-term mercury variations in tree rings of the permafrost forest,northeastern China

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Science China Earth Sciences 2022年第7期65卷 1328-1338页

作者： Huhu kang Xiaohong LIU Junming GUO Qiuliang ZHANG Yabo WANG Jie HUANG Guobao XU Guoju WU Wensen GE Shichang kang State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China University of Chinese Academy of Sciences Beijing 100049China Forest College Inner Mongolia Agricultural UniversityHohhot 010018China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China

Permafrost is a potential mercury(Hg)pool released by thawing,which can raise the risk of Hg pollution under global *** rings are useful archives of environment-specific Hg exposure over long *** determined Hg concentrations in tree rings of two dominant tree species(Larix gmelinii *** Pinus sylvestris ***)at permafrost sites in northeastern *** biweighted mean Hg concentrations ranged from 0.36 to 3.96 ng g^(-1) from 1840 to *** tree-ring width had no significant influence on the Hg *** Hg increased slightly before the 1970 s and peaked in the 1990 ***,the pine Hg concentration increased continuously until the 1930 s,decreased rapidly until the 1970 s,then rose to a peak in the late 1980 *** change of Hg concentrations in larch and pine revealed a time offset of 4 to 5 years,which implied possibly high mobility of Hg in pine tree *** Hg concentrations from 1920 to 1960 and subsequent decreases in isolated permafrost forests revealed the local geographical Hg cycling *** Hg concentrations and faster increases in larch suggest the role of additional winter Hg loading for the evergreen pine and species-specific differences in root absorption in response to melting *** results highlight possible geographical impacts on tree-ring Hg records,improve understanding of Hg cycles in permafrost forest,and suggest a need to sample additional species in a range of permafrost environments.

关键词： Tree rings Mercury Long-term variations Larch Pine Geographic environment Permafrost forest

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基于深度强化学习的无地图移动机器人导航

控制与决策 2024年第3期39卷 985-993页

作者：户高铭蔡克卫王芳康玉伟张家旭金兆一林远山大连海洋大学信息工程学院辽宁大连116023 大连海洋大学设施渔业教育部重点实验室辽宁大连116023 辽宁省海洋信息技术重点实验室辽宁大连116023 大连民族大学机电工程学院辽宁大连116023

针对传统导航方法对地图精度依赖和动态复杂场景适应差问题,提出一种基于课程学习的深度强化学习无地图自主导航算法.为了克服智能体稀疏奖励情况下学习困难的问题,借鉴课程学习思想,提出一种基于能力圈课程引导的深度强化学习训练方法... 详细信息

针对传统导航方法对地图精度依赖和动态复杂场景适应差问题,提出一种基于课程学习的深度强化学习无地图自主导航算法.为了克服智能体稀疏奖励情况下学习困难的问题,借鉴课程学习思想,提出一种基于能力圈课程引导的深度强化学习训练方法.此外,为了更好地利用机器人当前的碰撞信息辅助机器人做动作决策,引入碰撞概率的概念,将机器人当前感知到的障碍物信息以一种高层语义的形式进行表示,并将其作为导航策略输入的一部分编码至机器人当前观测中,以简化观测到动作的映射,进一步降低学习的难度.实验结果表明,所提出的课程引导训练和碰撞概率可令导航策略收敛速度明显加快,习得的导航策略在空间更大的场景成功率到达90%以上,行驶耗时减少53.5%73.1%,可为非结构化未知环境下的无人化作业提供可靠导航.

关键词：移动机器人自主导航无地图导航深度强化学习课程学习

基于多变量时空融合网络的风机数据缺失值插补研究

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自动化学报 2024年第6期50卷 1171-1184页

作者：詹兆康胡旭光赵浩然张思琪张峻凯马大中东北大学信息科学与工程学院沈阳110819 山东大学电气工程学院济南250100

风电场数据的完整性会因恶劣天气、输入信号丢失、传感器故障等原因遭到破坏,而大面积的数据缺失将给风机设备的运行和维护带来严峻考验.因此,提出一个多变量时空融合网络(Multivariate spatiotemporal integration network,MSIN)来解... 详细信息

风电场数据的完整性会因恶劣天气、输入信号丢失、传感器故障等原因遭到破坏,而大面积的数据缺失将给风机设备的运行和维护带来严峻考验.因此,提出一个多变量时空融合网络(Multivariate spatiotemporal integration network,MSIN)来解决缺失数据问题.首先,提出包含缺失值定位−指引机制的MSIN结构,揭示缺失部分数据的潜在信息,确保插补数据符合真实分布.其次,在网络中设计多视角时空卷积模块,捕捉同一风机多个变量与多个风机同一变量之间的局部空间和全局时间相关性,用于提高插补数据的真实性.接着,提出网络实时自更新机制,根据风电场实时变化情况实现在线调整,能够提升网络泛化能力,由此弥补重新训练模型的时间和空间成本高的缺陷.最后,通过真实的风机数据验证所提网络的有效性和优越性.相关分析结果表明,相较于MissForest等传统数据插补方法的插补性能,平均绝对误差(Mean absolute error,MAE)、平均绝对百分比误差(Mean absolute percentage error,MAPE)和均方根误差(Root mean square error,RMSE)分别下降18.54%、41.00%和3.15%以上.

关键词：风机数据数据插补时空特征生成对抗网络

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A new insight for stem cell therapy:apoptotic stem cells as a key player

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Signal Transduction and Targeted Therapy 2022年第9期7卷 3181-3183页

作者： Yuhe Huang Ziyi Bai kang Zhang Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of BiotherapyNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityNo.17Block 3Southern Renmin RoadChengduSichuan 610041PR China Zhuhai International Eye Center Zhuhai People's Hospital and The First Afliated Hospital of Faculty of MedicineMacao University of Science and TechnologyZhuhaiChina

Recently,two studies on therapeutic effects of stem cell therapy were published in Signal Transduction and Target Therapy1 and Nature Communications.2These studies have shed the light on a unique aspect of stem cell therapy which involves a previously unrecognized key player,namely apoptotic *** two publications have elucidated how the apoptotic cells exert immunomodulatory effects in stem cell therapy in several animal models.

关键词： apo therapy Therapy

碳/铝复合材料界面Al_(4)C_(3)相的形成与调控研究进展

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中国有色金属学报 2024年第5期34卷 1453-1474页

作者：李肖亮李昱桦董正学万梓涵任可聪邓海亮杨康吴操安徽工业大学先进金属材料绿色制备与表面技术教育部重点实验室马鞍山243002 安徽工业大学材料科学与工程学院先进陶瓷研究中心马鞍山243002 四川航天天盛装备科技有限公司成都610100

石墨烯、碳纳米管和碳纤维等碳材料作为铝基复合材料的增强体时,其界面润湿性差、与Al基体结合弱等缺点限制了其增强效果。利用C与Al反应使界面黏接形式转变为部分反应结合的形式,可有效提升碳/铝(C/Al)界面强度及其载荷与功能传递的效... 详细信息

石墨烯、碳纳米管和碳纤维等碳材料作为铝基复合材料的增强体时,其界面润湿性差、与Al基体结合弱等缺点限制了其增强效果。利用C与Al反应使界面黏接形式转变为部分反应结合的形式,可有效提升碳/铝(C/Al)界面强度及其载荷与功能传递的效率。然而,高温下C/Al界面反应易生成大量脆性Al_(4)C_(3),且会损伤增强体。针对C/Al界面Al_(4)C_(3)的调控,本文首先介绍了其形成机制、对C/Al复合材料界面结合和性能的作用,随后从碳增强体表面涂层、纳米颗粒修饰、Al基体合金化,以及复合制备、热加工与处理工艺优化等方面,综述了Al_(4)C_(3)生成量与形貌的控制研究及效果,最后展望了C/Al复合材料界面与性能的研究方向,以期通过碳增强体跨尺度设计与界面构型控制,挖掘石墨烯、碳纳米管和碳纤维增强Al基体的最大潜能。

关键词：铝基复合材料石墨烯碳纳米管碳纤维 Al_(4)C_(3)相