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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： yakun zhang Guofang GONG Huayong YANG Jianbin LI Liujie JING State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha Fluid Power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual operations.This study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart operation.Firstly,the definition,meaning,contents,and development modes of intelligent shield machines are proposed.The development status of the intelligent shield machine and its smart operation are then presented.After analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is proposed.Challenges and recommendations are given for achieving autonomous operation.This study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

Cu single atoms embedded on hollow g-C_(3)N_(4)nanospheres with enhanced charge transfer and separation for efficient photocatalysis

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Chinese Chemical Letters 2024年第2期35卷 455-459页

作者： Linlin zhang Jianjun Liao yakun Li Wei Sun Chengjun Ge Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Ecology and EnvironmentHainan UniversityHaikou 570228China Shandong Ocean Chemical Industry Scientific Research Institute Weifang 262737China

Establishing an effective charge transfer mechanism in carbon nitride(g-C_(3)N_(4))to enhance its photocatalytic activity remains a limiting nuisance.Herein,the combination design of a single Cu atom with hollow g-C_(3)N_(4)nanospheres(Cu-N_(3)structure)has been proven to offer significant opportunities for this crucial challenge.Moreover,this structure endows two pathways for charge transfer in the reaction,namely,the N atoms in the three-dimensional planar structure are only bonded with a single Cu atom,and charge transfer occurs between the plane and the layered structure due to the bending of the interlayered g-C_(3)N_(4)hollow nanospheres.Notably,Cu-N_(3)and hollow nanosphere structures have been certified to greatly enhance the efficiency of photogenerated carrier separation and transfer between the layers and planes by ultrafast spectral analysis.As a result,this catalyst possesses unparalleled photocatalytic efficiency.Specifically,the hydrogen production rate up to 2040μmol h^(−1) g^(−1),which is 51 times that of pure C_(3)N_(4)under visible light conditions.The photocatalytic degradation performance of tetracycline and oxidation performance of benzene is also expressed,with a degradation rate of 100%,a conversion of 97.3%and a selectivity of 99.9%.This work focuses on the structure-activity relationship to provide the possibilities for the development of potential photocatalytic materials.

关键词： g-C_(3)N_(4) Cu single atom Hollow nanospheres Charge transfer pathways Photocatalytic hydrogen production

Cobalt-doped TiO_(2)@C hierarchical nanocomposites derived from Ti_(3)C_(2) MXene as cathodes for hybrid magnesium-lithium batteries

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Nano Research 2024年第1期17卷 253-261页

作者： Xiaohui Li yakun Tang Lang Liu Yue zhang Yang Gao Mao Qian Wenjie Ma State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China

TiO_(2)has been explored in hybrid magnesium-lithium batteries(HMLBs)due to the advantages of low self-discharge and small volume expansion during ion insertion.However,how to improve the inherently low ionic and electrical conductivity of TiO_(2)is the problem that needs to be solved.In this work,a smart strategy is adopted to prepare cobalt-doped TiO_(2)@C(Co^(4+)-TiO_(2)@C)hierarchical nanocomposite derived from Co(II)(OH)n@Ti3C2.Compared with TiO_(2)@C(without cobalt doping),Co^(4+)-TiO_(2)@C shows the highest specific capacity(154.7 mAh·g^(-1)at 0.1 A·g^(-1)after 200 cycles)and extraordinary rate performance in HMLBs.The excellent electrochemical performance of Co4+-TiO_(2)@C is ascribed to the synergistic effect of the hierarchical structure and cobalt-doping.Both experimental results and density functional theory(DFT)calculation reveal that the cobalt-doping has effectively improved the electronic conductivity and reduced the Li+migration barrier.This work provides a new insight to design TiO_(2)-based cathode materials with high-performance in HMLBs.

关键词： Ti_(3)C_(2)MXene TiO_(2) hybrid magnesium-lithium batteries hierarchical structure cobalt-doping

Long-range Pt-Ni dual sites boost hydrogen evolution through optimizing the adsorption configuration

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Nano Research 2024年第5期17卷 3700-3706页

作者： Cong Liu Pengfang zhang Bing Liu Qian Meng Xuzhao Yang yakun Li Jingli Han Yao Wang Henan Province Engineering Research Center of Catalysis and Separation of Cyclohexanol College of Materials and Chemical EngineeringZhengzhou University of Light IndustryZhengzhou 450001China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology Liaocheng UniversityLiaocheng 252000China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringInternational Joint Research Center for Photoresponsive Molecules and MaterialsJiangnan UniversityWuxi 214122China

Elaborated design of catalytic systems with a specifically tailored site distance to match the intermediates could substantially improve reaction kinetics and boost catalytic activity under unfavorable reaction conditions.Considering the lower energy barriers of water splitting upon the synergy of dual sites,constructing synergistic Pt-M(M:transition metal)dual sites is an effective way to boost Pt with highly catalytic hydrogen evolution reaction(HER)performance.An unconventional“Ni(OH)_(2)-coated high-index Pt facets”was constructed to obtain long-range Pt-Ni dual sites,in which Ni composition as a water dissociation synergistic site can protect Pt from electrolyte corrosion and ensure efficient proton donation to Pt sites.The obtained long-range Pt-Ni dual sites present 3.84 mA·cm^(-1) of current density,which is 7.5 times specific activity higher than that of commercial Pt/C towards alkaline HER.The enhanced HER performance is attributed to synergistic catalysis on Pt-Ni dual sites accompanied by unconventional electron coupling.This work illustrates a new strategy to construct the long-range dual sites by unconventional strategy for fundamental electrocatalytic study of alkaline HER.

关键词： long-range Pt-Ni dual sites electron transfer hydrogen evolution reaction sites synergy

Helicobacter pylori and immunotherapy for gastrointestinal cancer

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The Innovation 2024年第2期5卷 51-60页

作者： Keren Jia Yang Chen Yi Xie Xicheng Wang Yajie Hu Yu Sun Yanshuo Cao Liyan zhang yakun Wang Zhenghang Wang Zhihao Lu Jian Li Xiaotian zhang Lin Shen Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Gastrointestinal OncologyPeking University Cancer Hospital&InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of PathologyPeking University Cancer Hospital&InstituteBeijing 100142China

Helicobacter pylori infection is associated with the risk of gastrointestinal(GI)cancers;however,its impact on immunotherapy for GI cancers remains uncertain.In this study,we included 10,122 patients who underwent ^(13)C-urea breath tests.Among 636 patients with Epstein-Barr virus–negative microsatellite-stable gastric cancer(GC)who were treated with anti-PD-1/PD-L1 therapy,H.pylori–positive patients exhibited significantly longer immune-related progression-free survival(irPFS)compared with H.pylori–negative patients(6.97 months versus 5.03 months,p<0.001,hazard ratio[HR]0.76,95%confidence interval[CI]0.62–0.95,p=0.015).Moreover,the H.pylori–positive group demonstrated a trend of 4 months longer median immune-related overall survival(irOS)than the H.pylori–negative group.H.pylori–positive GC displayed higher densities of PD-L1+cells and nonexhausted CD8+T cells,indicative of a“hot”tumor microenvironment.Transcriptomic analysis revealed that H.pylori–positive GC shared molecular characteristics similar to those of immunotherapy-sensitive GC.However,H.pylori–positive patients with DNA mismatch repair–deficient(dMMR)/microsatellite instability–high(MSI-H)colorectal adenocarcinoma and esophageal squamous cell carcinoma(ESCC)had shorter irPFS compared with H.pylori–negative patients(16.13 months versus not reached,p=0.042,HR 2.26,95%CI 1.13–4.50,p=0.021 and 5.57 months versus 6.97 months,p=0.029,HR 1.59,95%CI 1.14–2.23,p=0.006,respectively).The difference in irOS between H.pylori–positive and–negative patients had the same trend as that between dMMR/MSI-H colorectal adenocarcinoma and ESCC patients.We also identified a trend of shorter irPFS and irOS in H.pylori–positive liver cancer and pancreatic cancer patients.In summary,our findings supported that H.pylori infection is a beneficial factor for GC immunotherapy by shaping hot tumor microenvironments.However,in dMMR/MSI-H colorectal adenocarcinoma and ESCC patients,H.pylori adversely affects the efficacy of immunotherapy.

关键词： immunotherapy gastrointestinal pylori

Electromyography signal segmentation method based on spectral subtraction backtracking

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Optoelectronics Letters 2022年第10期18卷 623-627页

作者： CAI Huihui zhang yakun XIE Liang YIN Erwei YAN Ye MING Dong Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjin300072China Tianjin Artificial Intelligence Innovation Center(TAIIC) Tianjin300450China Defense Innovation Institute Academy of Military Sciences(AMS)Beijing100071China

Surface electromyography(EMG) is a bioelectrical signal that recognizes speech contents in a non-acoustic form. Activity detection is an important research direction in EMG research. However, in the low signal-to-noise ratio(SNR) environment, it is difficult for traditional methods to obtain accurate active signals. This paper proposes a new energy-based spectral subtraction backtracking(E-SSB) method to segment EMG active signal in the low SNR environment. Compared with traditional energy detection, the algorithm in this paper adds spectral subtraction(SS) to filter out the clutter, and raises a retrospective idea to improve the classification performance. The experiment results show the proposed activity detection method is more effective than other methods in the low SNR environment.

关键词： signal spectral method

基于多维投影时空事件帧的动态视觉传感手势识别

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系统仿真学报 2024年第3期36卷 649-658页

作者：康来张亚坤国防科技大学系统工程学院湖南长沙410073 国防科技大学大数据与决策实验室湖南长沙410073 中国人民解放军61081部队北京100089

基于视觉的手势识别是虚拟现实、游戏仿真等领域常用的人机交互手段。在实际应用中,手势动作快速变化将导致传统RGB相机或深度相机成像模糊,给手势识别带来巨大挑战。针对上述问题,利用动态视觉传感器捕捉高速手势运动信息,提出一种基... 详细信息

基于视觉的手势识别是虚拟现实、游戏仿真等领域常用的人机交互手段。在实际应用中,手势动作快速变化将导致传统RGB相机或深度相机成像模糊,给手势识别带来巨大挑战。针对上述问题,利用动态视觉传感器捕捉高速手势运动信息,提出一种基于多维投影时空事件帧(spatiotemporal event frame,STEF)的动态视觉数据手势识别方法。将时空信息嵌入到数据投影面融合形成多维投影时空事件帧,克服现有动态视觉信息事件帧表达方法时域信息丢失的局限性,提升动态视觉传感数据的特征表达能力。在此基础上,采用先进的脉冲神经网络对时空事件帧进行分类实现手势识别。在公开数据集上的识别精度达到96.67%,性能优于同类方法,表明该方法可显著提升动态视觉传感数据手势识别准确率。

关键词：动态视觉传感器手势识别多维投影时空事件帧脉冲神经网络

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工程建设企业创新的影响机理

清华大学学报（自然科学版） 2024年第2期64卷 235-242页

作者：张亚坤张旭腾唐文哲清华大学水利水电工程系水圈科学与水利工程全国重点实验室北京100084

在业务开展过程中,工程建设企业要解决技术问题、协调多方关系、适应客户需求及市场条件、兼顾环境保护和社会发展,企业需要通过不断创新提升自身能力,如何促进创新已成为工程建设企业面临的关键问题。该文从工程建设企业的视角出发,通... 详细信息

在业务开展过程中,工程建设企业要解决技术问题、协调多方关系、适应客户需求及市场条件、兼顾环境保护和社会发展,企业需要通过不断创新提升自身能力,如何促进创新已成为工程建设企业面临的关键问题。该文从工程建设企业的视角出发,通过问卷调研和访谈对工程建设企业创新进行了系统、深入的分析,构建了工程建设企业创新理论模型,综合考虑工程项目创新和企业创新能力,揭示了工程建设企业创新的影响机理及其对企业绩效的关键作用,揭示了企业创新制度、组织间知识共享、项目实施流程、工程项目创新、企业创新能力与企业绩效之间的关系。结果表明:企业创新制度能够影响组织间知识共享和项目实施流程,进而促进工程项目创新和提高企业创新能力,最终实现企业绩效提升。该研究结果可为工程建设企业提供重要的理论和实践指导。

关键词：建设企业工程项目创新企业创新能力企业绩效创新管理

TMKs-ABP1/ABLs:植物激素生长素的细胞表面受体复合物

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科学通报 2024年第7期69卷 809-811页

作者：张曹莉彭亚坤谭树堂中国科学技术大学生命科学与医学部生命科学学院前沿交叉科学与生物医学研究所合肥230027

植物激素是指在植物生长发育中起着调控作用的微量化合物.其中,生长素(auxin;主要天然形式为吲哚乙酸,IAA)占据无法取代的重要地位,也是第一种被发现的植物激素.生长素参与调控植物生长发育的多个方面,包括胚胎发育、维管组织形成、顶... 详细信息

植物激素是指在植物生长发育中起着调控作用的微量化合物.其中,生长素(auxin;主要天然形式为吲哚乙酸,IAA)占据无法取代的重要地位,也是第一种被发现的植物激素.生长素参与调控植物生长发育的多个方面,包括胚胎发育、维管组织形成、顶端优势、主根生长、侧根形成和果实发育等[1].然而,生长素如何协调如此复杂的生物学过程呢?

关键词：植物激素细胞表面受体顶端优势生长素胚胎发育维管组织侧根形成吲哚乙酸

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基于TLE数据的大气密度反演与校正

中国空间科学技术 2024年第1期44卷 54-64页

作者：张衷韬张亚坤王斌航天工程大学研究生院北京101400 航天工程大学电子与光学工程系北京101400

用于航天器轨道预报的热层密度模型普遍存在30%左右的误差,影响LEO卫星的精密轨道确定和载荷控制。基于低轨航天器平运动变化与大气密度的关系,使用GRACE(gravity recovery and climate experiment)卫星TLE数据反演2003、2007年沿轨大... 详细信息

用于航天器轨道预报的热层密度模型普遍存在30%左右的误差,影响LEO卫星的精密轨道确定和载荷控制。基于低轨航天器平运动变化与大气密度的关系,使用GRACE(gravity recovery and climate experiment)卫星TLE数据反演2003、2007年沿轨大气密度,通过比较反演值、模型值和实测值的关系分析误差产生原因,使用对数正态分布拟合密度比值。通过分析太阳辐射、地磁指数对大气密度变化的影响,提出一种基于空间环境指数的热层大气密度模型校正与预报方式。使用该方法对2003、2004、2007、2008年的MSIS86模型计算密度进行修正,将模型平均相对误差从33.33%~59.62%降低到11.55%~15.13%,太阳活动低年改进量是高年的1.5~2倍。对2009年经验模型结果进行预报校正,将预报误差降低36.49%,提高了模型精度。

关键词：热层密度反演 MSIS-86大气模型大气模型校正两行轨道根数空间环境指数