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半监督的移动对象离群轨迹检测算法

计算机研究与发展 2011年第11期48卷 2074-2082页

作者：黄添强余养强郭躬德秦小麟福建师范大学数学与计算机科学学院福州350007 清华大学计算机科学与技术系北京100084 南京航空航天大学信息科学与技术学院南京210016

移动数据的研究逐渐成为了数据挖掘研究领域的热点.已有的移动对象离群轨迹检测算法部分参数敏感且需人工调节,导致算法不稳定,可扩展性不理想;同时,已有算法完全根据自己主观定义的度量来探测离群轨迹,没有充分利用已知轨迹反映的信息... 详细信息

移动数据的研究逐渐成为了数据挖掘研究领域的热点.已有的移动对象离群轨迹检测算法部分参数敏感且需人工调节,导致算法不稳定,可扩展性不理想;同时,已有算法完全根据自己主观定义的度量来探测离群轨迹,没有充分利用已知轨迹反映的信息.因此,提出一种基于半监督技术的移动对象离群轨迹检测算法,利用半监督技术,根据已知的信息确定敏感参数,克服算法不稳定的缺点,并从整体与局部相结合的角度设计新的度量,以发现有意义的移动对象离群轨迹.实验表明该算法可以发现更有意义的移动对象离群轨迹并减少参数的人工调节.

关键词：移动对象离群轨迹半监督学习离群点挖掘数据挖掘

融合小波快捷连接生成对抗网络的面部性别伪造

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网络与信息安全学报 2023年第3期9卷 150-160页

作者：陈万泽黄丽清陈家祯叶锋黄添强罗海峰福建师范大学计算机与网络空间安全学院福建福州350117

面部属性编辑领域的主流方法由于数据以及模型架构的限制,存在如下两方面的问题:自编码器模型在编码以及解码阶段的瓶颈结构会丢失特征信息,以及在解码过程中逐阶段对源域特征进行连续的样式注入,使得生成图像中目标域信息占比过大,导... 详细信息

面部属性编辑领域的主流方法由于数据以及模型架构的限制,存在如下两方面的问题:自编码器模型在编码以及解码阶段的瓶颈结构会丢失特征信息,以及在解码过程中逐阶段对源域特征进行连续的样式注入,使得生成图像中目标域信息占比过大,导致生成图像丢失了源域的身份信息以及部分细节;在人脸图像中,图像人物的性别、种族或年龄等属性的差异会使得不同图像的频域信息组成差别较大,在无监督的训练前提下,当前主流网络框架并不能在样式注入阶段调整源域信息以及目标域信息之间的占比,导致生成图像仍然存在伪影。针对上述问题,基于生成对抗网络和图像到图像的翻译提出一种面部性别伪造模型,即融合快捷小波连接生成对抗网络(WscGAN)。通过对自编码器结构添加快捷连接,将不同编码阶段的输出通过小波变换进行特征级别的分解,再引入通道注意力机制将其进行逐个处理,以此动态改变在解码过程中不同频率的源域特征信息的比例,最终实现面部图像在性别属性上的伪造。为了验证所提模型的有效性,WscGAN分别在CelebA-HQ数据集和FFHQ数据集上进行了实验。实验结果表明,WscGAN在CelebA-HQ以及FFHQ数据集上均领先现有先进模型,其中弗雷歇起始距离分别提升5.4%和19.8%,特征度量相似度分别提升1.8%和4.1%。此外,定性的视觉对比结果充分体现了WscGAN可有效改善面部图像性别属性伪造的效果。

关键词：图像生成生成对抗网络图像到图像的翻译面部属性编辑小波变换

Shock-induced energy localization and reaction growth considering chemical-inclusions effects for crystalline explosives

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Defence Technology（防务技术） 2024年第3期33卷 278-294页

作者： Ruqin Liu Yanqing Wu Xinjie Wang Fenglei huang Xiaona huang Yushi Wen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072HubeiChina Institute of Chemical Materials China Academy of Engineering Physics(CAEP)Mianyang621999SichuanChina

Chemical inclusions significantly alter shock responses of crystalline explosives in macroscale gap experiments but their microscale dynamics origin remains *** shock-induced energy localization,overall physical responses,and reactions in a-1,3,5-trinitro-1,3,5-triazinane(a-RDX)crystal entrained various chemical inclusions were investigated by the multi-scale shock technique implemented in the reactive molecular dynamics *** indicated that energy localization and shock reaction were affected by the intrinsic factors within chemical inclusions,i.e.,phase states,chemical compositions,and *** atomic origin of chemical-inclusions effects on energy localization is dependent on the dynamics mechanism of interfacial molecules with free space volume,which includes homogeneous intermolecular compression,interfacial impact and shear,and void collapse and *** introducing various chemical inclusions,the initiation of those dynamics mechanisms triggers diverse decay rates of bulk RDX molecules and hereby impacts on growth speeds of final *** chemical inclusions can reduce the effectiveness of the void during the shock *** the shockwave velocity of 9 km/s,the parent RDX decay rate in RDX entrained amorphous carbon decreases the most and is about one fourth of that in RDX with a vacuum void,and solid HMX and TATB inclusions are more reactive than amorphous carbon but less reactive than dry air or acetone *** lessdense shocking system denotes the greater increases in local temperature and stress,the faster energy liberation,and the earlier final reaction into equilibrium,revealing more pronounced responses to the present intense *** quantitative models associated with the relative system density(RD_(sys))were proposed for indicating energy-localization mechanisms and evaluating initiation safety in the shocked crystalline ***_(sys)is defined by the density ratio of defective RDX to perfec

关键词： Shock responses Energy localization Crystalline explosives Chemical inclusions Reactive molecular dynamics

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结合小波变换高频信息的可控面部性别伪造

计算机科学 2023年第S2期50卷 340-349页

作者：陈万泽陈家祯黄丽清叶锋黄添强罗海峰福建师范大学计算机与网络空间安全学院福州350117

基于生成对抗网络(Generative Adversarial Network,GAN)的图像到图像的翻译(Image-to-Image Translation,I2I)技术在各种领域中取得了一系列突破,并广泛应用于图像合成、图像着色、图像超分辨率,特别是在面部属性操作方面获得了深入研... 详细信息

基于生成对抗网络(Generative Adversarial Network,GAN)的图像到图像的翻译(Image-to-Image Translation,I2I)技术在各种领域中取得了一系列突破,并广泛应用于图像合成、图像着色、图像超分辨率,特别是在面部属性操作方面获得了深入研究。为了解决目前I2I领域由于模型架构以及数据不均衡所导致的不同翻译方向的生成图像性能表现差异的问题,提出了一种HFIGAN(High Frequency Injection GAN)模型,实现了结合高频信息的可控面部性别伪造。首先在结合高频信息的小波模块中,将编码特征通过离散小波变换进行特征级的分解,将所得到的高频信息在解码阶段对等注入,使得在上采样过程中的源域与目标域之间的信息可以达成平衡状态。其次,针对I2I任务中多域转换在不同方向的翻译难度不一致的问题,通过对损失函数进行重新设计,将难易样本的损失进行放缩,提高难样本对模型的反馈,使模型更专注于难样本的训练从而提升模型性能。最后,提出基于风格特征的多样性正则项,将风格向量在不同空间中的距离度量添加至传统的多样性损失中进行监督,使得模型能在保持生成图像多样性的同时提升图像的生成质量。分别在CelebA-HQ数据集和FFHQ数据集上进行实验并验证了所提方法的有效性。在主流的I2I模型中结合所提损失进行了损失函数通用性验证。实验结果表明,与以往先进方法相比,HFIGAN在面部性别伪造方面性能更加优异,所提出的损失函数具备一定的通用性。

关键词：图像生成生成对抗网络图像到图像的翻译人脸属性编辑聚焦损失

Superiority of a Convolutional Neural Network Model over Dynamical Models in Predicting Central Pacific ENSO

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Advances in Atmospheric Sciences 2024年第1期41卷 141-154页

作者： Tingyu WANG Ping huang Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The application of deep learning is fast developing in climate prediction,in which El Ni?o–Southern Oscillation(ENSO),as the most dominant disaster-causing climate event,is a key *** studies have shown that deep learning methods possess a certain level of superiority in predicting ENSO *** present study develops a deep learning model for predicting the spatial pattern of sea surface temperature anomalies(SSTAs)in the equatorial Pacific by training a convolutional neural network(CNN)model with historical simulations from CMIP6 *** with dynamical models,the CNN model has higher skill in predicting the SSTAs in the equatorial western-central Pacific,but not in the eastern *** CNN model can successfully capture the small-scale precursors in the initial SSTAs for the development of central Pacific ENSO to distinguish the spatial mode up to a lead time of seven months.A fusion model combining the predictions of the CNN model and the dynamical models achieves higher skill than each of them for both central and eastern Pacific ENSO.

关键词： ENSO diversity deep learning ENSO prediction dynamical forecast system

Hierarchical model updating for high-speed maglev vehicle/guideway coupled system based on multiobjective optimization

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 788-804页

作者： Dexiang Li Jingyu huang College of Civil Engineering Tongji UniversityShanghai 200092China National Maglev Transportation Engineering R&D Center Tongji UniversityShanghai 201804China

The high-speed maglev vehicle/guideway coupled model is an essential simulation tool for investigating vehicle dynamics and mitigating coupled *** improve its accuracy efficiently,this study investigated a hierarchical model updating method integrated with field ***,a high-speed maglev vehicle/guideway coupled model,taking into account the real effect of guideway material properties and elastic restraint of bearings,was developed by integrating the finite element method,multi-body dynamics,and electromagnetic levitation ***,simultaneous in-site measurements of the vehicle/guideway were conducted on a high-speed maglev test line to analyze the system response and structural modal *** the hierarchical updating,an Elman neural network with the optimal Latin hypercube sampling method was used to substitute the FE guideway model,thus improving the computational *** multi-objective particle swarm optimization algorithm with the gray relational projection method was applied to hierarchically update the parameters of the guideway layer and magnetic force layer based on the measured modal parameters and the electromagnet vibration,***,the updated coupled model was compared with the field measurements,and the results demonstrated the model’s accuracy in simulating the actual dynamic response,validating the effectiveness of the updating method.

关键词： high-speed maglev vehicle/guideway coupled model field measurement model updating neural network multi-objective optimization

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基于压缩感知的视频异源篡改检测

计算机工程与应用 2011年第30期47卷 119-122页

作者：黄添强曾文赋福建师范大学数学与计算机科学学院福州350007 福建师范大学网络安全与密码技术重点实验室福州350007

考虑到视频序列固有噪声特征的特点,提出一种基于压缩感知的视频异源篡改检测算法。提取视频中每帧图像的噪声信息并建立噪声矩阵,通过引入压缩感知理论对噪声矩阵进行压缩,极大地降低每帧图像噪声信息的冗余度,对压缩噪声矩阵使用cos... 详细信息

考虑到视频序列固有噪声特征的特点,提出一种基于压缩感知的视频异源篡改检测算法。提取视频中每帧图像的噪声信息并建立噪声矩阵,通过引入压缩感知理论对噪声矩阵进行压缩,极大地降低每帧图像噪声信息的冗余度,对压缩噪声矩阵使用cos相似性衡量,得到帧图像间的相似度矩阵,并构造篡改度量,利用参数模型对视频的异源篡改图像进行检测。实验表明提出算法能以较小的压缩比对视频序列中的异源篡改位置进行有效检测,并得到比现有两种算法更高的篡改检测准确率。

关键词：噪声信息压缩感知 cos相似度视频篡改检测

Enhanced boron neutron capture therapy(BNCT)through controlled drug release via boron-loaded nanofiber mats

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Nano Research 2024年第8期17卷 7479-7492页

作者： Wenyong huang Yongjin Yang Yong Pan Shiwei Jing Yanxin Qi Yubin huang Faculty of Chemistry Northeast Normal UniversityChangchun 130024China Key Laboratory of Sustainable Advanced Functional Materials of Jilin Province Changchun 130024China School of Physics Northeast Normal UniversityChangchun 130024China

Boron neutron capture therapy(BNCT)is a novel binary therapy combining boron targeted drugs and neutron irradiation,which can selectively and effectively kill cancer cells at the cellular *** release of boron drug and its accumulation in tumor sites are the crux of ***,we developed a^(10)B-boric acid(^(10)BA)-loaded nanofiber applying for BNCT by in situ *** nanofibers were obtained by electrospinning technique using polyethylene glycol/polylactide(PEO/PLA)block *** changing the ratio of hydrophilicity to hydrophobicity of the nanofibers,the controlled release and the effective accumulation of boron 10 isotope(^(10)B)were achieved in ***^(10)B content in tumor could reach to 2540μg/g,significantly exceeding the required level of 20–50μg/g for BNCT *** pertinent DNA damage experiments,direct evidence and quantified data of BNCT-induced DNA damage in tumor cells were obtained for the first *** sequencing was employed to predict the molecular mechanisms and potential signaling pathways of BNCT,providing theoretical basis for future combined *** antitumor efficiency of BNCT was demonstrated by establishing mice model of subcutaneous tumor and tumor *** research presents a novel boron-loaded nanofiber mats for BNCT,which enables controlled drug release and holds significant potential in the treatment of unresectable or postoperative residual tumors.

关键词： boron neutron capture therapy nanofibers controlled release in situ administration

A Comprehensive Investigation on Shear Performance of Improved Perfobond Connector

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Structural Durability & Health Monitoring 2024年第3期18卷 299-320页

作者： Caiping huang Zihan huang Wenfeng You School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China

This paper presents an easily installed improved perfobond connector (PBL) designed to reduce the shearconcentration of PBL. The improvement of PBL lies in changing the straight penetrating rebar to the Z-typepenetrating rebar. To study the shear performance of improved PBL, two PBL test specimens which containstraight penetrating rebar and six improved PBL test specimens which contain Z-type penetrating rebars weredesigned and fabricated, and push-out tests of these eight test specimens were carried out to investigate andcompare the shear behavior of PBL. Additionally, Finite Element Analysis (FEA) models of the PBL specimenswere established and validated against the test results. Through FEA, the effects of concrete grade, perforatedplate’s aperture, Z-type penetrating rebar’s diameter, Z-type penetrating rebar’s bending angle, and bending lengthon shear behaviors were discussed. The results indicate that (1) Compared with PBL specimens with straightpenetrating rebars, Z-type penetrating rebar can significantly improve the shear resistance and shear stiffnessof the specimens. This enhanced performance can be mainly attributed to the increased adhesion of the transverserebar. (2) By comparing the load-slip curve, the slip of PBL test specimens which contain straight penetratingrebar increases rapidly and the bearing capacity decreases rapidly after concrete craking, while the bearingcapacity of Z-type penetrating rebar specimens decreases first and then increases gradually, showing betterductility. (3) The stress of the PBL shear connector with Z-type penetrating rebar is more uniform than thePBL shear connector with straight penetrating rebar, and the overall deformation is more uniform. (4) The higherthe concrete grade, the higher the shear bearing capacity and the better ductility of the new PBL. Increasing theaperture of the perforated plate or the diameter of the rebar has a very limited effect on the improvement of theshear capacity of PBL. Through the system

关键词： PBL penetrating rebar push-out test load-slip curve shear capacity finite element analysis