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Recent progress on impact induced reaction mechanism of reactive alloys

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Defence Technology（防务技术） 2024年第7期37卷 69-95页

作者： yansong yang Chuanting Wang Yuanpei Meng Yue Ma Lei Guo Yuan He Zhichao Sun Yong He School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

In recent years,in order to improve the destructive effectiveness of munitions,the use of new types of destructive elements is an important way to improve destructive *** a new type of reactive material,reactive alloy contains a large portion of reactive metal elements(Al,Mg,Ti,Zr,etc.),which breaks up under high-velocity impact conditions,generating a large number of high-temperature combustible fragments,which undergo a violent combustion reaction with *** with traditional metal polymers(Al-PTFE)and other reactive composites,it has higher density and strength,excellent mechanical properties and broader application ***,researchers have mainly investigated the impact energy release mechanism of reactive alloys through impact tests,and found that there are several important stages in the process of the material from fragmentation to reaction,i.e.,impact fragmentation of the material,rapid heating and combustion *** paper focuses on three problems that need to be solved in the impact-induced energy release process of reactive alloys,namely:the fragmentation mechanism and size distribution law of the fragments produced by the impact of the material on the target,the relationship between the transient temperatures and the size of the fragments,and the reaction temperatures and size thresholds of the fragments to undergo the chemical *** current status of the research of the above problems is reviewed,some potential directions to reveal the impact induced reaction mechanism of reactive alloy is discussed.

关键词： Reactive alloys Impact Fragmentation Mass and size distribution Shock temperature rise Adiabatic shear Combustion

Advanced RF filters for wireless communications

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Chip 2023年第4期2卷 1-26页

作者： Kai yang Chenggong He Jiming Fang Xinhui Cui Haiding Sun yansong yang Chengjie Zuo School of Microelectronics University of Science and Technology of ChinaHefei 230088China YUNTA Technologies and ANUKI Technologies Hefei 230088China Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China

This paper provides a comprehensive review of advanced radio fre-quency(RF)filter technologies available in miniature chip or inte-grated circuit(IC)form for wireless communication *** RF filter technologies were organized according to the time-line of their introduction,in conjunction with each generation of wireless(cellular)communication standards(1G to 5G).This ap-proach enabled a clear explanation of the corresponding invention history,working principles,typical applications and future develop-ment *** article covered commercially successful acoustic filter technologies,including the widely used surface acoustic wave(SAW)and bulk acoustic wave(BAW)filters,as well as electromag-netic filter technologies based on low-temperature co-fired ceramic(LTCC)and integrated passive device(IPD).Additionally,emerg-ing filter technologies such as IHP-SAW,suspended thin-film lithium niobate(LiNbO3 or LN)resonant devices and hybrid were also *** order to achieve higher performance,smaller form factor and lower cost for the wireless communication industry,it is believed that fundamental breakthroughs in materials and fabrication tech-niques are necessary for the future development of RF filters.

关键词： RF filter Acoustic wave Piezoelectric Electromagnetic Hy-brid

Research on the Teaching Reform of “Big Data Analysis and Visualization” Course for College Students

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Journal of Contemporary Educational Research 2024年第8期8卷 59-63页

作者： yansong yang Xiaodan Chen Smart City College Beijing Union UniversityBeijing 100101China

Under the background of the big data era,the education of big data majors is undergoing a profound teaching reform and *** the increasing role of big data technology in analysis and decision-making,updating and expanding the teaching content of big data majors has become particularly *** the era of big data,modern enterprises have put forward new and higher demands for big data talents,which not only include traditional data analysis skills but also knowledge of data visualization and information *** address these challenges,big data education needs to reform and innovate in the development and utilization of teaching content,methods,and *** paper proposes teaching models and reform methods for big data majors and analyzes corresponding teaching reforms and innovations to meet the requirements of the new development of big data *** traditional classroom teaching method is no longer sufficient to meet the learning needs of students,and more dynamic and interactive teaching methods,such as case studies,flipped classrooms,and project-based learning,are becoming increasingly *** innovative teaching methods can more effectively cultivate students’practical operation skills and independent thinking while allowing them to better learn advanced knowledge in a real big-data *** addition,the paper also discusses the construction of big data processing and analysis platforms,as well as innovative teaching management and evaluation systems to improve teaching quality.

关键词： Data science Big data technology Course Teaching reform

Forest Fire Detection Using Artificial Neural Network Algorithm Implemented in Wireless Sensor Networks

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ZTE Communications 2015年第2期13卷 12-16页

作者： Yongsheng Liu yansong yang Chang Liu Yu Gu Network Technology Research Institute China United Network Communications Corporation Limited Department of Computer Science Hefei University of Technology

A forest fire is a severe threat to forest resources and human life, In this paper, we propose a forest-fire detection system that has an artificial neural network algorithm implemented in a wireless sensor network （WSN）. The proposed detection system mitigates the threat of forest fires by provide accurate fire alarm with low maintenance cost. The accuracy is increased by the novel multi- criteria detection, referred to as an alarm decision depends on multiple attributes of a forest fire. The multi-criteria detection is implemented by the artificial neural network algorithm. Meanwhile, we have developed a prototype of the proposed system consisting of the solar batter module, the fire detection module and the user interface module.

关键词： forest fire detection artificial neural network wireless sensor network

Efficient and wideband acousto-optic modulation on thin-film lithium niobate for microwave-to-photonic conversion

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Photonics Research 2021年第7期9卷 1182-1190页

作者： AHMED E.HASSANIEN STEFFEN LINK yansong yang EDMOND CHOW LYNFORD L.GODDARD SONGBIN GONG Holonyak Micro and Nanotechnology Laboratory Department of Electrical and Computer EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA

Microwave photonics,a field that crosscuts microwave/millimeter-wave engineering with optoelectronics,has sparked great interest from research and commercial sectors. This multidisciplinary fusion can achieve ultrawide bandwidth and ultrafast speed that were considered impossible in conventional chip-scale microwave/millimeterwave systems. Conventional microwave-to-photonic converters,based on resonant acousto-optic modulation,produce highly efficient modulation but sacrifice bandwidth and limit their applicability for most real-world microwave signal-processing applications. In this paper,we build highly efficient and wideband microwaveto-photonic modulators using the acousto-optic effect on suspended lithium niobate thin films. A wideband microwave signal is first piezoelectrically transduced using interdigitated electrodes into Lamb acoustic waves,which directly propagates across an optical waveguide and causes refractive index pertp urbation through the photoelastic effect. This approach is power-efficient,with phase shifts up to 0.0166 rad∕m W over a 45μm modulation length and with a bandwidth up to 140 MHz at a center frequency of 1.9 GHz. Compared to the state-ofthe-art,a 9×more efficient modulation has been achieved by optimizing the acoustic and optical modes and their interactions.

关键词： wideband millimeter waveguide

书画“双胞案”应该怎样研究——对《董其昌〈纪游图册〉“双胞案”再议》的回应

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中国国家博物馆馆刊 2018年第10期 84-90页

作者：杨岩松辽宁省喀左县公共文化服务中心朝阳122300

王洪伟文章对两个版本《纪游图册》存在12对册页雷同的统计结果,以及对另外四册的分析,核心证据值得商榷:其依据《董其昌书画编年图目》以二手材料为主,而此书相关图片存在出版错误,受此影响的统计和分析必然会出现偏差,导致对两个《纪... 详细信息

王洪伟文章对两个版本《纪游图册》存在12对册页雷同的统计结果,以及对另外四册的分析,核心证据值得商榷:其依据《董其昌书画编年图目》以二手材料为主,而此书相关图片存在出版错误,受此影响的统计和分析必然会出现偏差,导致对两个《纪游图册》的判断存在一定问题。本文阐述了书画"双胞案"应该怎样研究的问题。书画"双胞案"类问题的鉴定,本质是区分原创(真迹)与复制(摹本)。虽然由于复制导致彼此雷同或高度相似,但艺术风格的阶段性特征无论在何种载体都是真实的体现,仅仅是呈现的效果程度有差异而已。因此,这类鉴定主要是风格表现角度的检验,而不是风格是否存在、是否符合的探讨,更与史料价值的探讨无关。所以,王文列举"台北本"董其昌绘画阶段性风格以及游踪史料,对于辨别真迹与摹本并没有任何意义,不构成有效证据。

关键词：董其昌纪游图册台北本安徽本书画鉴定

反式-1-苯磺酰基-2-甲基-4-羟基-2-丁烯的合成

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石油化工 2007年第4期36卷 374-377页

作者：陈田杨运泉杨彦松陈健刘文英湘潭大学化工学院湖南湘潭411105

以异戊二烯为原料,经与苯磺酰氯加成、水解乙酰化、皂化3步反应,合成了辅酶Q10的重要中间体——反式-1-苯磺酰基-2-甲基-4-羟基-2-丁烯(简称终产物);分别考察了3步反应的反应条件;用傅里叶变换红外光谱和核磁共振表征了其结构。实验结... 详细信息

以异戊二烯为原料,经与苯磺酰氯加成、水解乙酰化、皂化3步反应,合成了辅酶Q10的重要中间体——反式-1-苯磺酰基-2-甲基-4-羟基-2-丁烯(简称终产物);分别考察了3步反应的反应条件;用傅里叶变换红外光谱和核磁共振表征了其结构。实验结果表明,加成反应的适宜条件为:氯化亚铜为催化剂,三乙胺盐酸盐为相转移助催化剂,乙腈为溶剂,90～100℃下密闭带压(约0.6M Pa)反应2h,n(异戊二烯)∶n(苯磺酰氯)=1.2,中间产物反式-1-苯磺酰基-2-甲基-4-氯-2-丁烯的收率为75%;水解乙酰化、皂化反应的适宜条件为:120～125℃下常压回流反应4h,0～5℃下碱性水解反应3h,以体积比为1∶1的乙酸乙酯-乙醚混合溶剂进行结晶精制。3步反应终产物的总收率为60%;终产物经液相色谱法分析,纯度达到99%。

关键词：辅酶Q10 异戊二烯苯磺酰氯反式-1-苯磺酰基-2-甲基-4-羟基-2-丁烯催化加成反应水解乙酰化皂化

基于MR-T2WI影像组学模型预测宫颈鳞癌临床分期

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中国医学影像技术 2021年第5期37卷 725-730页

作者：杨易冯峰傅爱燕杨彦松葛亚琼龚海鹏南通大学附属肿瘤医院放射科江苏南通226000 GE医疗中国上海210000

目的观察基于MR-T2WI影像组学模型预测宫颈鳞癌临床分期的价值。方法对159例经术后或活检病理证实的宫颈鳞癌患者采集盆部MRI,根据国际妇产科联盟(FIGO)分期系统及病理结果分为早期组(ⅠB~ⅡA期,n=73)和晚期组(ⅡB~Ⅳ期,n=86)。按照7∶... 详细信息

目的观察基于MR-T2WI影像组学模型预测宫颈鳞癌临床分期的价值。方法对159例经术后或活检病理证实的宫颈鳞癌患者采集盆部MRI,根据国际妇产科联盟(FIGO)分期系统及病理结果分为早期组(ⅠB~ⅡA期,n=73)和晚期组(ⅡB~Ⅳ期,n=86)。按照7∶3比例将患者随机分为训练集(n=113)和验证集(n=46)。训练集包括52例早期、61例晚期宫颈鳞癌,验证集含21例早期及25例晚期宫颈鳞癌。提取轴位T2WI中病灶的影像组学特征,以最大相关最小冗余和最小绝对收缩选择算子回归分析方法筛选最优影像组学特征,构建预测早、晚期宫颈鳞癌的影像组学模型。分析影像组学模型的拟合优度,采用受试者工作特征(ROC)曲线评估模型的预测效能,以决策曲线分析(DCA)评估模型的临床应用价值。结果共提取396个影像组学特征,最终筛选11个最优影像组学特征,并以之构建预测早、晚期宫颈鳞癌的影像组学模型。影像组学模型在训练集和验证集中的拟合优度均佳(χ^(2)=2.68、8.87,P均>0.05);其在训练集及验证集中的曲线下面积(AUC)均为0.80。DCA显示,阈值取0.10~1.00时,影像组学模型的净收益较大。结论基于MR-T2WI的影像组学模型对预测宫颈鳞癌临床分期具有较高价值。

关键词：子宫颈肿瘤肿瘤,鳞状细胞肿瘤分期磁共振成像影像组学

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Iu-Flex技术及应用

邮电设计技术 2007年第2期 43-47页

作者：杨艳松中讯邮电咨询设计院研发部

详细介绍了Iu-Flex的基本原理,包括核心网络(CN)节点标识、路由机制等,给出了移动通信网中利用Iu-Flex技术实现CN节点间负载均衡、负载重分配的方法和步骤。

关键词： Iu-Flex 池网络资源标识符 NAS节点选择功能负载均衡负载重分配