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The Adjacency Codes of the First Yellow Graphs

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系统科学与复杂性学报:英文版 2023年第4期36卷 1757-1768页

作者： SHI Minjia li shitao KIM Jon-Lark SOLE Patrick Key Laboratory of Intelligent Computing and Signal Processing Ministry of EducationSchool of Mathematical SciencesAnhui UniversityHefei 230601China State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijing 100093China School of Mathematical Sciences Anhui UniversityHefei 230026China Department of Math Sogang UniversitySeoulSouth Korea Aix Marseille Univ CNRSCentrale MarseilleI2MMarseilleFrance

The authors study the binary codes spanned by the adjacency matrices of the strongly regular graphs(SRGs)on at most two hundred vertices whose existence is unknown.The authors show that in length less than one hundred they cannot be cyclic,except for the exceptions of the SRGs of parameters(85,42,20,21)and(96,60,38,36).In particular,the adjacency code of a(85,42,20,21)is the zero-sum code.In the range[100,200]the authors find 29 SRGs that could possibly have a cyclic adjacency code.

关键词： Cyclic codes strongly regular graphs adjacency codes self-orthogonal codes

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206P型转向架临修轴箱弹簧更换工艺研究

农业装备与车辆工程 2024年第4期62卷 64-66页

作者：李世涛李昀逸孙镱玮中车青岛四方机车车辆股份有限公司山东青岛266111 青岛伟隆阀门股份有限公司山东青岛266111

轨道车辆运行过程中,转向架的轮对、轴箱弹簧及摇枕弹簧等部件会出现故障,需及时更换故障部件。为优化工艺流程,使故障配件的更换更加高效快捷,针对转向架轴箱弹簧的非架车工况,对轴箱弹簧更换工艺流程进行了优化设计。试验结果表明,采... 详细信息

轨道车辆运行过程中,转向架的轮对、轴箱弹簧及摇枕弹簧等部件会出现故障,需及时更换故障部件。为优化工艺流程,使故障配件的更换更加高效快捷,针对转向架轴箱弹簧的非架车工况,对轴箱弹簧更换工艺流程进行了优化设计。试验结果表明,采用优化后的工艺流程,在普通轨道无抬车机条件下,人工抬起车体及构架一端可实现轴箱弹簧更换,为转向架临修轴箱弹簧等故障配件更换提供了新的工艺技术支持。

关键词：轨道车辆转向架轴箱弹簧工艺技术

基于近似Booth4编码的新型低功耗乘法器

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电工技术 2024年第8期 135-138,143页

作者：陆雨龙李少珍向石涛武汉轻工大学电气与电子工程学院湖北武汉430000

随着物联网应用的不断智能化和高集成化,对新型高速及低功耗运算单元的需求日益迫切,因此终端设备需要不断降低功耗和提升运算速率。针对运算单元功耗高的问题,在保证精准度的前提下,对Booth4编码进行近似优化处理,并结合符号补偿技术... 详细信息

随着物联网应用的不断智能化和高集成化,对新型高速及低功耗运算单元的需求日益迫切,因此终端设备需要不断降低功耗和提升运算速率。针对运算单元功耗高的问题,在保证精准度的前提下,对Booth4编码进行近似优化处理,并结合符号补偿技术和乘法系数优化的方法,提升传统Booth4乘法器的运算速率,降低乘法器的功耗。与传统Booth4乘法器相比,该新型Booth4乘法器的功耗和延时分别降低了16.9%和22.9%。为了验证新型Booth4乘法器的实用性,利用其对图像Lena和Gameraman进行图像滤波处理,结果显示图像质量参数为优。

关键词： Booth算法乘法器近似高斯滤波低功耗

LECF: recommendation via learnable edge collaborative filtering

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Science China(Information Sciences) 2022年第1期65卷 116-130页

作者： shitao XIAO Yingxia SHAO Yawen li Hongzhi YIN Yanyan SHEN Bin CUI School of Computer Science (National Pilot Software Engineering School) Beijing University of Posts and Telecommunications Beijing Key Lab of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications School of Information Technology and Electrical Engineering The University of Queensland Department of Computer Science and Engineering Shanghai Jiao Tong University Department of Computer Science and Technology Peking University National Engineering Laboratory for Big Data Analysis and Applications Peking University

The core of recommendation models is estimating the probability that a user will like an item based on historical interactions. Existing collaborative filtering(CF) algorithms compute the likelihood by utilizing simple relationships between objects, e.g., user-item, item-item, or user-user. They always rely on a single type of object-object relationship, ignoring other useful relationship information in data. In this paper, we model an interaction between user and item as an edge and propose a novel CF framework, called learnable edge collaborative filtering(LECF). LECF predicts the existence probability of an edge based on the connections among edges and is able to capture the complex relationship in data. Specifically, we first adopt the concept of line graph where each node represents an interaction edge; then calculate a weighted sum of similarity between the query edge and the observed edges(i.e., historical interactions) that are selected from the neighborhood of query edge in the line graph for a recommendation. In addition, we design an efficient propagation algorithm to speed up the training and inference of LECF. Extensive experiments on four public datasets demonstrate LECF can achieve better performance than the state-of-the-art methods.

关键词： collaborative filtering recommender system implicit feedback edge-edge similarity line graph

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堆载对排桩支护深基坑稳定性的影响研究

施工技术（中英文） 2024年第3期53卷 65-69页

作者：张炳焜程世涛李彦骏四川省建筑科学研究院有限公司四川成都610000 四川交通职业技术学院四川成都611130 西南交通大学土木工程学院四川成都610031

为深入研究堆载等临时荷载对深基坑稳定性的影响,以成都市某深基坑为工程背景,采用ABAQUS有限元软件开展堆载大小和作用位置对基坑变形和稳定性的影响研究。研究结果表明,堆载的存在能增大基坑冠梁的水平位移,这种影响随着堆载作用位置... 详细信息

为深入研究堆载等临时荷载对深基坑稳定性的影响,以成都市某深基坑为工程背景,采用ABAQUS有限元软件开展堆载大小和作用位置对基坑变形和稳定性的影响研究。研究结果表明,堆载的存在能增大基坑冠梁的水平位移,这种影响随着堆载作用位置趋近基坑边缘而急剧增加。堆载的存在降低了基坑安全系数,对于同等大小的堆载,随着堆载作用位置越靠近基坑边缘,基坑安全系数降低幅度越大。堆载对基坑破坏模式有着较大影响,在堆载敏感区内,随着堆载作用距离的增加,破坏滑移面由直线形向y形过渡,由整体滑移破坏模式向整体滑移-局部剪切耦合破坏模式过渡。堆载使桩周产生了负摩阻力,增加了基坑失稳的风险。堆载处理方式遵循快速安全的原则,在提高安全系数的前提下快速卸荷。

关键词：深基坑堆载稳定性位移有限元分析

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溃疡性结肠炎的肠道免疫研究进展

中国中医基础医学杂志 2024年第1期30卷 168-175页

作者：李洋宋志前鲁欣悦王淳彭诗涛张婷宁张弛首都医科大学附属北京中医医院北京100010 中国中医科学院中医基础理论研究所北京100700 中国中医科学院广安门医院北京100053

溃疡性结肠炎(ulcerative colitis,UC)是一种病因尚不十分明确的结肠和直肠慢性非特异性疾病。UC与肠道免疫关系密切,肠相关淋巴组织以及固有层含有丰富的免疫细胞,对于维持肠道免疫稳态具有重要作用。辅助性T细胞(T helper cell, Th)17... 详细信息

溃疡性结肠炎(ulcerative colitis,UC)是一种病因尚不十分明确的结肠和直肠慢性非特异性疾病。UC与肠道免疫关系密切,肠相关淋巴组织以及固有层含有丰富的免疫细胞,对于维持肠道免疫稳态具有重要作用。辅助性T细胞(T helper cell, Th)17/调节性T细胞(T regulatory cell, Treg)失衡与UC肠道免疫稳态息息相关,而Th17/Treg细胞的分化和功能受到细胞代谢重编程的影响。本文主要从与UC相关的肠相关淋巴组织以及固有层内多种免疫因素、Th17/Treg细胞代谢重编程以及中药免疫调节治疗UC现状3个方面进行综述,以期为UC相关研究提供参考。

关键词：溃疡性结肠炎肠道免疫 Th17细胞 Treg细胞代谢重编程

Chitosan-based carbon dots with multi-color-emissive tunable fluorescence and visible light catalytic enhancement properties

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Nano Research 2023年第2期16卷 1835-1845页

作者： Qiong Wu Shouyun Zhang Shuang li Yan Yan shitao Yu Ruiyang Zhao Lang Huang State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China

Carbon quantum dots(CQDs)are receiving increasing attention for their excellent photostability,low toxicity,and tunable fluorescence performance,but it is still challenging to prepare full-spectrum CQDs using only one single set of precursor and solvent.In this study,P and N co-doped carbon dots(N,PR-CQDs)with multi-color-emissive tunable fluorescence from blue to green and orange were synthesized from bio-based chitosan,employing phosphoric acid as solvent and dopant.The introduction of phosphoric acid successfully shortens the manufacturing reaction time,and the heteratomic functional groups of P–O/P=O on surface of carbon dots enrich the surface defect states,promoting n–π*transition,and therefore changing their electron structure/energy level to reduce the band gap,thus facilitating emission at long wavelength.Specifically,increasing phosphoric acid concentration leads to characteristic excitation peaks red shift from 320 to 420 nm with the characteristic emission peaks red shift from 406 to 503 nm.A new emission peak at 610 nm appears,enabling N,PR-CQDs exhibit double emission peaks with fluorescence color from green to yellow to orange.After compositing with carbon nitride(g-C3N4),N,PR-CQDs work as photosensitizer and effectively narrow the energy gap(Eg)of g-C3N4 from 2.75 to 2.40 eV,endowing the photocatalyst higher visible light capture ability and broader light response region.The photocatalytic degradation rate of rhodamine B(RhB)under visible light irradiation reaches up to 98.39%within 60 min using N,P20%-CQDs/g-C3N4 as catalyst,which is 1.4 times that of pure g-C3N4,and it is demonstrated that·O2−is the major active substance contributing for RhB degradation by de-ethyl and aromatic ring breakage.

关键词： carbon dots multicolor luminescence chitosan visible light catalysis photosensitizer

A dual metal-organic framework strategy for synthesis of FeCo@NC bifunctional oxygen catalysts for clean energy application

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Chinese Journal of Chemical Engineering 2022年第3期35卷 161-168页

作者： Jun Chen liandong li liu Yang Chang Chen shitao Wang Yan Huang Dapeng Cao State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

Developing high efficient bifunctional oxygen electrocatalysts for clean energy applications like Zin-air battery(ZAB)is highly desired,because it would reduce the cost and speed up the practical application of ZAB.Here we use a dual metal-organic framework(MOF)synthesis strategy to prepare the N-doped carbon supported bimetallic FeCo nanoparticle catalysts(marked as FeCo@NC)by pyrolysis of Zn CoZIF/MIL-101(Fe)composite.The FeCo@NC exhibits remarkable electrocatalytic activity for ORR with half-wave potential of 0.89 V vs.the reversible hydrogen electrode(RHE)and robust durability for both ORR and OER(oxygen reduction reaction and oxygen evolution reaction),which is attributed to the generation of Fe_(0.26)Co_(0.74) crystalline phase and mesopores due to the dual-MOF synthesis strategy.The rechargeable ZAB based on FeCo@NC air electrode shows a maximum energy density of139.6 mW·cm^(-2) and excellent cyclic stability over 130 h,significantly surpassing the Pt and Ir-based ZAB.The present work provides a useful dual-MOF synthesis strategy for preparing high-performance multifunctional catalysts for ORR,OER and hydrogen evolution reaction(HER).

关键词： Metal Organic Frameworks Zeolite imidazole framework Bifunctional electrocatalysts FeCo alloy Zn-air battery

Enhancement of the angular rotation measurement sensitivity based on SU(2)and SU(1,1) interferometers

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Photonics Research 2017年第6期5卷 136-141页

作者： JUN liU WENXIAO liU shitao li DONG WEI HONG GAO FUli li Key Laboratory of Quantum Information and Quantum Optoelectronic Devices of Shaanxi Province School of ScienceXi'an Jiaotong University

We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam with a vacuum beam in an SU(2) interferometer, we get the sensitivity of the angular rotation measurement as 1/(2N^(1/2)l). We can surpass the limit of the angular rotation measurement in an SU(1,1) interferometer by combining a coherent beam with a vacuum beam or a squeezed vacuum beam when the probe beam has OAM. Without injection, the sensitivity can reach 1/(2N^(1/2)l). In addition, by employing another construction of an SU(1,1) interferometer where the pump beam has OAM, with the same injection of an SU(1,1) interferometer, the sensitivity of the angular rotation measurement can be improved by a factor of 2, reaching 1/(4Nl). The results confirm the potential of this technology for precision measurements in angular rotation measurements.

关键词： OAM interferometers Enhancement of the angular rotation measurement sensitivity based on SU and SU