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Journal of Materials Science & Technology 2014年第4期30卷 408-416页

作者： Haile yan Xiang zhao Nan Jia Yiran zheng Tong He Key Laboratory for Anisotropy and Texture of Materials(MOE) Northeastern University Northeastern University Research Academy

Texture evolution in nickel, copper and α-brass that are representative of face-centered-cubic （fcc） materials with different stacking fault energy （SFE） during cold rolling was systematically investigated. X-ray diffraction, scanning electron microscopy and electron backscatter diffraction techniques were employed to characterize microstructures and local orientation distributions of specimens at different thickness reductions. Besides, Taylor and Schmid factors of the {111} 〈110〉 slip systems and {111} 〈112〉 twin systems for some typical orientations were utilized to explore the relationship between texture evolution and deformation microstructures. It was found that in fcc metals with low SFE at large deformations, the copper-oriented grains rotated around the 〈110〉 crystallographic axis through the brass-R orientation to the Goss orientation, and finally toward the brass orientation. The initiation of shear banding was the dominant mechanism for the above-mentioned texture transition.

关键词： Face-centered-cubic ahoy Texture Rolling Shear band

Granular classifier:Building traffic granules for encrypted traffic classification based on granular computing

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Digital Communications and Networks 2024年第5期10卷 1428-1438页

作者： Xuyang Jing Jingjing zhao zheng yan Witold Pedrycz Xian Li State Key Laboratory on Integrated Services Networks School of Cyber Engineering Xidian University Department of Electrical and Computer Engineering University of Alberta Institute for Future (IFF) Qingdao University

Accurate classification of encrypted traffic plays an important role in network ***,current methods confronts several problems:inability to characterize traffic that exhibits great dispersion,inability to classify traffic with multi-level features,and degradation due to limited training traffic *** address these problems,this paper proposes a traffic granularity-based cryptographic traffic classification method,called Granular Classifier(GC).In this paper,a novel Cardinality-based Constrained Fuzzy C-Means(CCFCM) clustering algorithm is proposed to address the problem caused by limited training traffic,considering the ratio of cardinality that must be linked between flows to achieve good traffic ***,an original representation format of traffic is presented based on granular computing,named Traffic Granules(TG),to accurately describe traffic structure by catching the dispersion of different traffic *** granule is a compact set of similar data with a refined boundary by excluding *** on TG,GC is constructed to perform traffic classification based on multi-level *** performance of the GC is evaluated based on real-world encrypted network traffic *** results show that the GC achieves outstanding performance for encrypted traffic classification with limited size of training traffic and keeps accurate classification in dynamic network conditions.

关键词： Encrypted traffic classification Semi-supervised clustering Granular computing Anomaly detection

腹型过敏性紫癜患儿的临床、内镜及病理学特点

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中华儿科杂志 2007年第11期45卷 814-817页

作者：李中跃黄晓磊陈洁陈飞波楼金玕江米足章许平赵正言浙江大学医学院附属儿童医院消化科杭州310003 浙江大学医学院附属儿童医院儿童保健科杭州310003

目的研究腹型过敏性紫癜患儿的临床表现、内镜及病理学特点,以提高对腹型过敏性紫癜的诊断水平。方法以浙江大学医学院附属儿童医院2002年1月-2007年5月住院的57例行上消化道内镜检查时未出现皮肤紫癜患儿为研究对象,回顾性分析腹型过... 详细信息

目的研究腹型过敏性紫癜患儿的临床表现、内镜及病理学特点,以提高对腹型过敏性紫癜的诊断水平。方法以浙江大学医学院附属儿童医院2002年1月-2007年5月住院的57例行上消化道内镜检查时未出现皮肤紫癜患儿为研究对象,回顾性分析腹型过敏性紫癜患儿的临床、内镜及病理学资料。结果消化道症状主要为腹痛46例(80.7%)、呕吐32例(56.1%)、便血11例(19.3%)、腹泻4例(7.0%)、腹胀1例(1.8%);同时伴关节肿痛3例(5.3%)。实验室检查主要为外周血白细胞增高(33例,57.9%),1/5左右的病例出现 C 反应蛋白升高、白蛋白降低或腹腔积液情况。内镜下主要表现37例为略高出黏膜的点状出血和淤斑或成片状(64.9%),14例出现糜烂或多发溃疡伴出血(24.6%),4例颗粒状或结节状增生(7.0%),弥漫性出血2例(3.5%)。病变在十二指肠降段出现率最高且最严重(55例,96.5%),其次为十二指肠球部(32例,56.1%)、胃(18例,31.6%),食道较少(1例,1.8%)。组织病理学呈毛细血管炎表现,3例(5.3%)的患儿同时伴幽门螺杆菌感染。49例(86.0%)患儿在内镜检查后1～7 d 内出现皮肤紫癜,8例至出院未出现皮肤紫癜,其中2例失访,6例(10.5%)随访至今(1～5年)未见皮肤紫癜。结论十二指肠降部病变在腹型过敏性紫癜极其常见,上消化道内镜检查对腹型过敏性紫癜有极高的诊断价值。

关键词：紫癜过敏性内窥镜检查胃肠道儿童

Guest editorial:Blockchain-enabled technologies for cyber-physical systems and big data applications

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Digital Communications and Networks 2022年第5期8卷 589-590页

作者： zheng yan Qinghua zheng Yulei Wu Yaliang zhao Mohammed Atiquzzaman Xidian University China Xi'an Jiaotong University China University of Exeter UK Henan University China&St.Francis Xavier UniversityCanada University of Oklahoma USA

*** and motivation Cyber-Physical System(CPS)refers to the seamless integration of the physical processes,computational components,and Internet-of-Things(IoT)devices such as sensors,actuators,and so *** of CPS include smart grids,autonomous transportation systems,medical monitoring,process control systems,robotic systems,and automatic pilot avionics.

关键词： autonomous smart IoT

肾外夹角对外生型肾乏脂肪血管平滑肌脂肪瘤与肾透明细胞癌的鉴别诊断价值

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临床放射学杂志 2025年第1期44卷 133-137页

作者：张小梅李娜赵艳王滔乐山市人民医院放射医学科 614000

目的探讨肾外夹角对外生型肾乏脂肪血管平滑肌脂肪瘤(AMLmf)与肾透明细胞癌(ccRCC)的鉴别诊断价值。方法回顾性分析经手术和病理证实的ccRCC患者55例共56个病灶,AMLmf患者20例共22个病灶,通过形态学分析两组肿瘤差异,测量肿瘤的肾外夹... 详细信息

目的探讨肾外夹角对外生型肾乏脂肪血管平滑肌脂肪瘤(AMLmf)与肾透明细胞癌(ccRCC)的鉴别诊断价值。方法回顾性分析经手术和病理证实的ccRCC患者55例共56个病灶,AMLmf患者20例共22个病灶,通过形态学分析两组肿瘤差异,测量肿瘤的肾外夹角并定量分析两组间的差异。结果假包膜、劈裂征及“冰激凌蛋筒征”对AMLmf与ccRCC的鉴别有统计学差异(P<0.05);两组肿瘤的肾外较大夹角及较小夹角值间差异有统计学意义。受试者工作特征(ROC)曲线分析显示肾外较大夹角、肾外较小夹角、劈裂征、“冰激凌蛋筒征”及假包膜鉴别AMLmf与ccRCC的曲线下面积(AUC)值分别为0.925、0.983、0.638、0.727、0.731,五种指标联合的AUC值为0.996,明显高于单一指标。结论肾外夹角、假包膜、劈裂征及“冰激凌蛋筒征”有助于AMLmf与ccRCC的鉴别诊断,联合五种影像学特征的诊断效能更高。

关键词：体层摄影术 X线计算机肾外夹角肾乏脂肪血管平滑肌脂肪瘤肾透明细胞癌

Butyl ether as Co-diluent in medium-concentrated electrolyte for Li-S battery

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Journal of Energy Chemistry 2023年第10期85卷 343-347,I0010页

作者： Xirui Kong Yayun zheng Lang He Du Wang yan zhao The Institute of Technological Sciences Wuhan UniversityWuhan 430000HubeiChina

1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been hindered by the “shuttle effect” and Li anode corrosion [2,3]. Highly concentrated electrolytes(HCEs) have been proposed as a solution, as they can inhibit the dissolution of lithium polysulfide and promote homogeneous lithium deposition [4].

关键词： Lithium-sulfur battery Diluted electrolyte Butyl ether Co-diluent

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球轴承刚度斜弹簧计算方法

轴承 2025年第1期 69-75页

作者：赵联春赵纪辉晏丽明王东上海斐赛轴承科技有限公司上海201199 洛阳摩梯普润滑技术有限公司河南洛阳471611 上海斐耐润滑技术有限公司上海201612

针对传统轴承刚度计算方法计算过程复杂,计算结果正确性存疑的问题,提出了一种斜弹簧计算方法,以角接触球轴承为例,推导了受联合载荷、高速运转和仅受中心轴向载荷、中低速运转2种极端情形下的轴承刚度计算公式,斜弹簧计算方法整个过程... 详细信息

针对传统轴承刚度计算方法计算过程复杂,计算结果正确性存疑的问题,提出了一种斜弹簧计算方法,以角接触球轴承为例,推导了受联合载荷、高速运转和仅受中心轴向载荷、中低速运转2种极端情形下的轴承刚度计算公式,斜弹簧计算方法整个过程无需微分和矩阵运算,物理意义清晰,正确性能够自证,计算过程简洁,计算精度高。并与虚功原理法、刚度投影法、准静态模型的增量法进行对比,结果表明:与虚功原理法误差较小,进一步证明了斜弹簧计算方法的正确性;与刚度投影法、准静态模型的增量法误差较大,两者所依据的物理基础不实的计算结果正确性存疑。

关键词：滚动轴承角接触球轴承刚度弹簧载荷变形

SCIM: Incorporating secure communication and interference management in one operation

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Digital Communications and Networks 2023年第2期9卷 512-522页

作者： zhao Li Pintian Lyu Jun Li Zhixian Chang Jia Liu zheng yan School of Cyber Engineering Xidian UniversityXi'an710126China Technol.on Commun.Net.Lab The 54th Research Inst.of China Elec.Technol.Group CorpShijiazhuang050081China School of Telecommun.and Inf.Engineering Xi'an University of Posts&TelecommunXi'an710071China School of Computer Science and Technology Xidian UniversityXi'an710126China The Department of Comnet Aalto UniversityEspoo02150Finland

Due to the broadcast nature of wireless communications,users’data transmitted wirelessly is susceptible to security/privacy ***,as a result of the limitation of spectrum resources,massive wireless connections will incur serious interference,which may damage the efficiency of data ***,improving both efficiency and secrecy of data transmission is of research *** this paper,we propose a wireless transmission scheme by taking both Secure Communication(SC)and Interference Management(IM)into account,namely *** this scheme,an SCIM signal is generated by the legitimate transmitter(Tx)and sent along with the desired signal,so that the SCIM signal can interact with and suppress the environmental interference at the legitimate receiver(Rx).Meanwhile,the SCIM signal may interfere with the eavesdropper in the coverage of legitimate transmission so as to deteriorate the eavesdropping ***,the secrecy of desired transmission is *** this way,both the transmission efficiency and privacy are ***,by taking various transmission preferences into account,we develop different implementations of SCIM,including Interference Suppression First SCIM(ISF-SCIM),Data Transmission First SCIM(DTF-SCIM),Anti-Eavesdropping First SCIM(AEF-SCIM),and Secrecy Rate Maximization SCIM(SRM-SCIM).Our in-depth simulation results have shown the proposed methods to effectively improve the efficiency and secrecy of the legitimate transmission.

关键词： Physical-layer security Secure communication Anti-eavesdropping Interference management Secrecy rate

Simulation of Extreme Updrafts in the Tropical Cyclone Eyewall

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Advances in Atmospheric Sciences 2020年第7期37卷 781-792页

作者： yan zheng Liguang WU Haikun zhao Xingyang ZHOU Qingyuan LIU Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China Jiangsu Institute of Meteorological Sciences Nanjing 210009China

Strong vertical motion(>10 m s-1)has profound implications for tropical cyclone(TC)structure changes and *** extreme updrafts in the TC are occasionally observed in real TCs,the associated small-scale features remain *** on an analysis of the extreme eyewall updrafts in two numerical experiments conducted with the Advanced Research version of the Weather Research and Forecasting(WRF)model,in which the large-eddy simulation(LES)technique was used with the finest grid spacings of 37 and 111 m,for the first time this study demonstrates that the simulated extreme updrafts that occur mainly in the enhanced eyewall convection on the down-shear left side are comparable to available *** simulated extreme updraft exhibits relatively high frequencies in the lower(750 m),middle(6.5 km)and upper(13 km)troposphere,which are associated with different types of small-scale *** the lower-level extreme updraft is mainly related to the tornado-scale vortex,the extreme updraft at upper levels is closely associated with a pair of counter-rotating horizontal rolls oriented generally along the TC tangential flow,which are closely associated with the enhanced eyewall *** extreme updraft at middle levels is related to relatively complicated small-scale *** study suggests that extreme updrafts can be simulated when the grid spacing is about 100 m or less in the WRF-LES framework,although the simulated small-scale features need further verification in both observation and simulation.

关键词： cyclone extreme troposphere

Reductive amination of n-hexanol to n-hexylamine over Ni-Ce/γ-Al_(2)O_(3) catalysts

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Frontiers of Chemical Science and Engineering 2023年第1期17卷 82-92页

作者： Pengfei Li Huijiang Huang zheng Wang Ziying Hong yan Xu Yujun zhao School of Chemical Engineering and Technology Tianjin UniversityKey Laboratory for Green Chemical Technology of Ministry of EducationTianjin 300072China

The amination of alkyl alcohols is one of the most promising paths in synthesis of aliphatic ***,cerium doped nickel-based catalysts were synthesized and tested in a gas-phase amination of n-hexanol to *** was found that the activity of the Ni/γ-Al_(2)O_(3)catalyst is significantly improved by doping an appropriate amount of *** presence of cerium effectively inhibits the agglomeration of nickel particle,resulting in better Ni *** Ni particle size plays critical role on the catalytic activity,higher turnover frequency of n-hexanol amination was *** doping also improves the reduction ability of nickel and enhances the interactions between Ni and the catalyst *** weak acid sites were also found in those cerium doped catalysts,which promote another key step—ammonia dissociative adsorption in this reaction *** overall synergy of Ni nanoparticles and acid sites of this Ni-Ce/γ-Al_(2)O_(3)catalyst boosts its superior catalytic performance in the amination of n-hexanol.

关键词： amination alcohol cerium nickel acidity interaction