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攻击标签信息的堆栈式支持向量机

计算机科学 2020年第1期47卷 110-116页

作者：金耀徐丽亚吕慧琳顾苏杭常州大学信息科学与工程学院江苏常州213164 江南大学数字媒体学院江苏无锡214122 常州轻工职业技术学院信息工程学院江苏常州213164

真实数据集中存在的对抗样本易导致分类器取得较差的分类性能,但如果其能够被合理利用,分类器的泛化能力将得到显著提高。针对现有大部分分类器并没有涉及对抗样本信息的问题,提出一种攻击标签信息的堆栈式支持向量机。该方法从给定的... 详细信息

真实数据集中存在的对抗样本易导致分类器取得较差的分类性能,但如果其能够被合理利用,分类器的泛化能力将得到显著提高。针对现有大部分分类器并没有涉及对抗样本信息的问题,提出一种攻击标签信息的堆栈式支持向量机。该方法从给定的初始数据集中选取一定比例的样本,并攻击所选取样本的标签,使之成为对抗样本,即将样本标签替换成其他不同类型的标签,利用支持向量机训练包含对抗样本的数据集,从而生成对抗支持向量机。计算对抗支持向量机的输出误差相对于输入样本的一阶梯度信息,并将其嵌入到输入样本特征中以更新输入样本。将更新后的样本输入到下一个对抗支持向量机中,并重新训练。以堆栈方式级联一定数目的对抗支持向量机,直至取得最好的分类性能。原理分析与实验结果表明,基于对抗样本的一阶梯度信息不仅提供了分类器输出与输入之间的一种正相关关系,而且为堆栈式支持向量机中的子分类器提供了一种新的堆栈方式,并提高了分类器的整体性能。

关键词：堆栈结构对抗样本标签攻击支持向量机

Investigation of edge states variation in valley photonic crystals by modulating the refractive index of domain walls

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Optoelectronics Letters 2025年第3期21卷 160-166页

作者： ZHANG Run ZHONG Xingli lin Zhongxi QIU Weibin SU hui Key Laboratory of Optoelectronic Materials Chemistry and Physics Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices Fujian Institute of Research on the Structure of Matter Chinese Academy of Science University of Chinese Academy of Sciences Chinese Academy of Sciences College of Information Science and Engineering Huaqiao University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics, since the valley degree of freedom was introduced into photonic system. Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated. In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls, and the geometric difference between the dielectric columns of the sublattices. Straight photonic crystal waveguides with three types of domain walls (bearded, zigzag, armchair) are constructed. Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands. Our findings might have significant implications in the field of novel optical devices.

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“互联网+”视角下的住区停车位工作日共享机制研究

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工程管理学报 2018年第2期32卷 68-73页

作者：李玉龙毛鹏罗杰吕茁琳罗会琳中央财经大学管理科学与工程学院北京100081

针对日益严重的停车难问题,以盘活存量为视角提出"互联网+"模式下的住区停车位工作日盘活机制,不但是一种很好的商业模式,而且还是用来缓解乃至解决城市停车难的重要手段。从市场、技术、资金3个角度阐述了该盘活机制的可行性,在此基础... 详细信息

针对日益严重的停车难问题,以盘活存量为视角提出"互联网+"模式下的住区停车位工作日盘活机制,不但是一种很好的商业模式,而且还是用来缓解乃至解决城市停车难的重要手段。从市场、技术、资金3个角度阐述了该盘活机制的可行性,在此基础上分析总结了盘活机制的关键要素,基于车位提供者、意愿停车人、物业管理方3个行为主体,阐述了停车位盘活机制的运行原理和系统构成。并选取了北京市的一个小区进行了案例模拟测算。结果发现,住区停车位盘活机制在比较繁华、写字楼办公地比较多的商业区具有可行性。"互联网+停车"的住区停车位工作日盘活机制对缓解停车难、促进停车产业发展具有重要意义。

关键词：互联网+ 住区停车位工作日盘活机制

Divergent synthesis of chiral amines via Ni-catalyzed chemo-and enantioselective hydrogenation of alkynone imines

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Science China Chemistry 2023年第11期66卷 3186-3192页

作者： Yuchuan Ma Kai Liu lin He hui lv Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832000China Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationSauvage Center for Molecular SciencesKey Laboratory of Biomedical Polymers of Ministry of Education&College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China

Ligand-mediated nickel-catalyzed asymmetric hydrogenation of alkynone imines has been achieved. By using Ni(OAc)_2·4H_2O/(S,S)-Ph-BPE complex as a catalyst, the chemo-and enantioselective hydrogenation of alkynone imines occurred efficiently to afford chiral propargyl amines with high yields and excellent enantioselectivities(up to 99% yield, >99% ee), leaving the readily reducible alkynyl group intact. Both the C=N and C≡C bonds of alkynone imines were hydrogenated efficiently in the presence of Ni(OAc)_2·4H_2O and Josiphos SL-J011-1, furnishing unfunctionalized chiral imines efficiently(up to 99% yield, >99% ee).The(Z)-allylamines and(E)-allylamines were also efficiently prepared from alkynone imines by the combination of the different catalytic systems. The preliminary mechanism study revealed that the reduction of alkynone imines was a stepwise process and the C=N bonds were preferably hydrogenated in the complete reduction of alkynone imines. The synthetic utility of this method was demonstrated by its application in the late-stage modification of the antiviral drug Zidovudine and the concise synthesis of chiral dibenzoazepine.

关键词： alkynone imine asymmetric hydrogenation propargyl amine enantioselectivity chiral amine

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利用中高能破碎和敲出反应研究非稳定核结构

原子核物理评论 2010年第4期27卷 390-398页

作者：叶沿林 FAISAL Jamil-Qureshi 楼建玲葛愉成吕林辉曹中鑫肖军李奇特陈天逸杨帆北京大学物理学院和核物理与核技术国家重点实验室北京100871

中高能区的破碎和敲出反应,由于机制相对简单、对核的表面敏感、理论处理比较成熟等原因,在非稳定核的晕结构、壳移动等奇特性质研究中发挥了独到作用。针对次级束流强度较弱、能散较大等特点,实验上发展和应用了逆运动学有效立体角完... 详细信息

中高能区的破碎和敲出反应,由于机制相对简单、对核的表面敏感、理论处理比较成熟等原因,在非稳定核的晕结构、壳移动等奇特性质研究中发挥了独到作用。针对次级束流强度较弱、能散较大等特点,实验上发展和应用了逆运动学有效立体角完全测量、轻重靶结合、高精度消色差磁谱仪、前向中子谱仪、在束γ测量等技术手段,大大提升了实验的探测能力和选择性。从物理问题探索和实验路线演变的角度,回顾了非稳定核破碎和敲出反应的发展过程与启示,并探讨未来的走向。

关键词：破碎反应非稳定核核结构反应机制核探测技术

参芎葡萄糖注射液协同防治重症患者深静脉血栓的临床疗效

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微循环学杂志 2017年第2期27卷 21-25,30页

作者：朱俊臣陈侣林李卉尧娟兰英成都大学附属医院重症医学科成都610081

目的:观察参芎葡萄糖注射液防治重症患者深静脉血栓形成疗效并探讨其机制。方法:141例继发性血栓倾向重症患者按其治疗方法分为对照组(n=68)和观察组(n=73)。对照组采用标准化常规抗凝治疗;观察组在对照组基础上加用参芎葡萄糖注射液(10... 详细信息

目的:观察参芎葡萄糖注射液防治重症患者深静脉血栓形成疗效并探讨其机制。方法:141例继发性血栓倾向重症患者按其治疗方法分为对照组(n=68)和观察组(n=73)。对照组采用标准化常规抗凝治疗;观察组在对照组基础上加用参芎葡萄糖注射液(100ml静滴,1次/天),两组疗程均为7天。比较两组治疗后深静脉血栓发生率和治疗前后血液流变学指标(高切和低切全血表观黏度、血浆黏度、红细胞压积、血小板聚集率)、凝血纤溶指标[血浆凝血酶原时间(PT)、部分凝血活酶时间(APTT)、纤维蛋白原(Fib)、D-二聚体(D-D)、血小板计数(PLT)]以及炎性因子[肿瘤坏死因子-α(TNF-α)、白细胞介素-1(IL-1)、白细胞介素-6(IL-6)]水平变化。观察治疗期间两组患者出血事件发生率。结果:治疗后观察组深静脉血栓发生率明显低于对照组(P0.05)。结论:参芎葡萄糖注射液能较好地协同防治深静脉血栓形成,且不增加出血事件,这可能与其改善血液流变学及凝血指标,减轻炎症有关。

关键词：参芎葡萄糖注射液重症患者血液流变学炎症

A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： Qiong Zhang lin-lv lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

Guest editorial: AI and edge computing driven technologies and applications

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Digital Communications and Networks 2023年第2期9卷 448-449页

作者： Jianhui lv Yuhui Shi hui Cheng Zhiwei lin Lianbo Ma Peng Cheng Laboratory China Southern University of Science and Technology China University of Hertfordshire UK Queen's University Belfast UK Northeastern University China

*** Emerging networking paradigms,including Information-Centric Networking(ICN)[1],Software-Defined Networking(SDN)[2],Mobile Satellite Communication Networks(MSCN)[3],and Internet of Vehicles(IoV)[4],have faced some severe *** example,the dynamic network environment makes it very hard to optimize resource *** addition,these networking paradigms usually have heterogeneous features,making it difficult to schedule traffic among different kinds of *** challenges can be addressed by the adaptive learning of Artificial Intelligence(AI)[5,6]and the edge caching of edge *** can also help establish a relatively optimal routing strategy and perform congestion control by learning the dynamic network *** like AI,edge computing[7–10]can help provide fast response to users,and deploy edge servers with strong computing and storage capabilities can greatly improve the performance of 4K/8K and VR/***,despite their ability to improve network performance,there are still many *** example,the integrated architectures and frameworks need to be clearly identified,and the related protocols need to be better defined.

关键词： network computing edge

Error- and loss-tolerant bundle fragment authentication for space DTNs

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Frontiers of Computer Science 2014年第6期8卷 1012-1023页

作者： Xixiang lv hui LI The National Key Lab of Integrated Services Networks Xidian University Xi'an 710071 China

To ensure the authenticity and integrity of bundles, the in-transit PDUs of bundle protocol （BP） in space delay/disruption-tolerant networks （DTNs）, the bundle security protocol specification （IRTF RFC6257） suggested using a digital signature directly over each bundle. However, when bundle fragment services are needed, this mechanism suffers from heavy computational costs, bandwidth overheads and energy consumption. In this paper, we address the fragment authentication issue for BP by exploiting the combination of RS error correction and erasure codes with the help of batch transmission characteristic of DTNs. The RS error correction and erasure codes are adopted to allow the receivers to locate the false/injected fragments and reconstruct the only one signature shared by all fragments of a bundle, even if some other fragments are lost or routed to a different path. Getting only partial authentic fragments, a DTN node is able to detect and filter the false/injected fragments, and authenticate the origin of a bundle as well. Such an approach tolerates high delays, unexpected link disruption and the BP nature of routing fragments of the same bundle possibly via different paths. The performance analysis demonstrates that both of our schemes, which follow our generic idea based on RS codes, significantly reduce bandwidth overheads and computational costs as compared to the prior works.

关键词： space-based delay tolerant networks bundle authentication information security.