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A Sentence Retrieval Generation Network Guided Video Captioning

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Computers, Materials & Continua 2023年第6期75卷 5675-5696页

作者： Ou ye Mimi Wang Zhenhua yu Yan fu Shun Yi Jun Deng College of Computer Science and Technology Xi’an University of Science and TechnologyXi’an710054China College of Safety and Engineering Xi’an University of Science and TechnologyXi’an710054China

Currently,the video captioning models based on an encoder-decoder mainly rely on a single video input *** contents of video captioning are limited since few studies employed external corpus information to guide the generation of video captioning,which is not conducive to the accurate descrip-tion and understanding of video *** address this issue,a novel video captioning method guided by a sentence retrieval generation network(ED-SRG)is proposed in this ***,a ResNeXt network model,an efficient convolutional network for online video understanding(ECO)model,and a long short-term memory(LSTM)network model are integrated to construct an encoder-decoder,which is utilized to extract the 2D features,3D features,and object features of video data *** features are decoded to generate textual sentences that conform to video content for sentence ***,a sentence-transformer network model is employed to retrieve different sentences in an external corpus that are semantically similar to the above textual *** candidate sentences are screened out through similarity ***,a novel GPT-2 network model is constructed based on GPT-2 network *** model introduces a designed random selector to randomly select predicted words with a high probability in the corpus,which is used to guide and generate textual sentences that are more in line with human natural language *** proposed method in this paper is compared with several existing works by *** results show that the indicators BLEU-4,CIDEr,ROUGE_L,and METEOR are improved by 3.1%,1.3%,0.3%,and 1.5%on a public dataset MSVD and 1.3%,0.5%,0.2%,1.9%on a public dataset MSR-VTT *** can be seen that the proposed method in this paper can generate video captioning with richer semantics than several state-of-the-art approaches.

关键词： Video captioning encoder-decoder sentence retrieval external corpus RS GPT-2 network model

Tensile and fracture properties of Ti-62A alloy plate with different microstructures

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Rare Metals 2012年第5期31卷 420-423页

作者： LIU Rui HUI Songxiao ye Wenjun yu Yang fu Yanyan SONG Xiaoyun DENG Xiguang State Key Laboratory of Nonferrous Metals & Processes General Research Institute for Nonferrous Metals Beijing 100088 China

Ti-62A alloy plates with three different types of microstructure, fully equiaxed, bimodal, and Widmanstatten, were obtained by various heat treatments to investigate the effects of microstructure on the tensile and fracture properties at room temperature. The results reveal that Widmanstatten microstructure exhibits good damage tolerance behavior considering strength, fracture toughness, and fatigue crack growth behavior, while the bimodal microstructure shows good comprehensive properties considering the plasticity synthetically. Optical microscopy (OM) and scanning electron microscopy (SEM) microstructure analyses on fracture and fatigue crack path demonstrate that the dependence of mechanical properties and fatigue crack growth behavior on microstructural feature are attributed to the α lamellae width and the α colony size. © The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2012.

关键词： Brittleness Damage tolerance Fatigue crack propagation Fatigue of materials Fracture toughness Microstructural evolution Optical microscopy Scanning electron microscopy Tensile properties

Detection and Estimation of False Data Injection Attacks for Load Frequency Control Systems

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 861-870页

作者： Jun ye Xiang yu Hangzhou Innovation Institute Beihang UniversityHangzhouChina School of Automation Science and Electrical Engineering Beihang UniversityBeijingChina

False data injection attacks(FDIAs)against the load frequency control(LFC)system can lead to unstable operation of power *** this paper,the problems of detecting and estimating the FDIAs for the LFC system in the presence of external disturbances are ***,the LFC system model with FDIAs against frequency and tie-line power measurements is ***,a design procedure for the unknown input observer(UIO)is presented and the residual signal is generated to detect the *** UIO is designed to decouple the effect of the unknown external disturbance on the residual *** that,an attack estimation method based on a robust adaptive observer(RAO)is proposed to estimate the state and the FDIAs *** order to improve the performance of attack estimation,the H¥technique is employed to minimize the effect of external disturbance on estimation errors,and the uniform boundedness of the state and attack estimation errors is proven using Lyapunov stability ***,a two-area interconnected power system is simulated to demonstrate the effectiveness of the proposed attack detection and estimation algorithms.

关键词： External disturbance false data injection attacks load frequency control robust adaptive observer unknown input observer

Transient simulation of a pump-turbine with misaligned guide vanes during turbine model start-up

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Acta Mechanica Sinica 2014年第5期30卷 646-655页

作者： ye-Xiang Xiao Ruo-fu Xiao State Key Laboratory of Hydroscience and Engineering & Department of Thermal Engineering Tsinghua University College of Water Resources and Civil Engineering China Agricultural University

Experimental studies of a model pump-turbine S-curve characteristics and its improvement by misaligned guide vanes （MGV） were extended to prototype pump turbine through 3-D transient flow simulations. The unsteady Reynolds-averaged Navier-Stokes equations with the SST turbulence model were used to model the transient flow within the entire flow passage of a reversible pump-turbine with and without misaligned guide vanes during turbine model start-up. The unstable S-curve and its improvement by using misaligned guide vane were verified by model test and simulation. The transient flow calculations were used to clarify the variations of pressure pulse and internal flow behavior in the entire flow passage. The use of misaligned guide vanes can eliminate the S-curve characteristics of a pump-turbine, and can significantly increase the pressure pulse amplitude in the entire flow passage and the runner radial forces during start-up. The MGV only decreased the pulse amplitude on the guide vane suction side when the rotating speed was less than 50% rated speed. The hydraulic reason is that the MGV dramatically changed the flow patterns inside the entire flow passage, and destroyed the symmetry of the flow distribution inside the guide vane and runner.

关键词： Transient flow. Pump turbine. Misaligned guide vane Model test Pressure pulse

Habitat influences on diversity of bacteria found on German cockroach in Beijing

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Journal of Environmental Sciences 2009年第2期21卷 249-254页

作者： fu Xue ye Lefu GE Feng State Key Laboratory of lntegrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100080 China

Cockroaches are worldwide indoor pests carrying microorganisms of medical importance. German cockroaches （Blattella germanica） were sampled in five habitats （hospital, restaurant, office home, and market） in Beijing, and the bacteria were isolated from their external surface and alimentary tract and identified using a Biolog identification system. Cockroach densities significantly differed among habitats （market 〉 home 〉 office 〉 restaurant 〉 hospital）. However, no significant differences in bacterial abundance carried by individual German cockroaches （of either sex） were found among habitats. The bacterial abundance in the gut was significantly higher than that on the surface. There were no significant differences in bacterial species richness observed among habitats, sex, carrying position or their interaction. Cluster analysis showed that cockroach densities and bacterial abundance found in the market differed significantly from the other four habitats. The bacterial diversity was not significantly reduced in sensitive facilities such as hospital and restaurant, even though pesticide and bactericide were more frequently applied there. The implications of these findings were discussed in this article.

关键词： German cockroaches Blattella germanica diversity bacteria

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面向自动语音识别系统的对抗样本生成方法

计算机科学与探索 2025年第1期19卷 253-263页

作者：于振华苏玉璠叶鸥丛旭亚西安科技大学计算机科学与技术学院西安710054

通过对系统进行对抗攻击可以检测系统漏洞,进而提高系统鲁棒性。然而,对抗攻击前往往需要系统的参数信息,这使得攻击条件受限。为此,结合一种新的量子粒子群优化算法,提出一种黑盒有目标对抗攻击方法。该方法通过在原始样本中添加微小噪... 详细信息

通过对系统进行对抗攻击可以检测系统漏洞,进而提高系统鲁棒性。然而,对抗攻击前往往需要系统的参数信息,这使得攻击条件受限。为此,结合一种新的量子粒子群优化算法,提出一种黑盒有目标对抗攻击方法。该方法通过在原始样本中添加微小噪声,构造差异化粒子群,作为初始对抗样本种群;基于记忆搜索的领域重分布策略得到当前种群的全局最优粒子,从而生成初始对抗样本;融入扩维和自适应权重位置更新,使得种群更接近目标;根据对抗样本与目标语句的编辑距离,继续优化初始对抗样本,生成最终对抗样本。为了验证方法的攻击效果,在GoogleSpeech、LibriSpeech以及CommonVoice数据集上,对语音识别模型DeepSpeech进行实验,将目标语句设置为不同场景中的常见语音指令。实验结果表明,提出的方法在三个数据集上成功率都优于对比方法,其中在Common Voice数据集上的成功率比对比方法提升了10个百分点。同时,召集志愿者对生成的对抗样本噪声强度进行主观评估,其中82.4%的对抗样本被志愿者判断为没有噪声或噪声很小。

关键词：对抗攻击语音识别黑盒攻击样本生成量子粒子群算法梯度评估方法

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Spatio-temporal variations of vegetation carbon use efficiency and potential driving meteorological factors in the Yangtze River Basin

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Journal of Mountain Science 2020年第8期17卷 1959-1973页

作者： ye Xu-chun LIU fu-hong ZHANG Zeng-xin XU Chong-yu LIU Jia Chongqing Key Laboratory of Karst Environment&School of Geographical Sciences of Southwest University Chongqing 400715China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Department of Geosciences University of Oslo N-0316Norway State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Institute of Water Resources and Hydropower ResearchBeijing 100038China

Understanding of the vegetation dynamics is essential for addressing the potential threats of terrestrial *** recent years,the vegetation coverage of the Yangtze River Basin(YRB)has increased significantly,yet the spatio-temporal variations and potential driving meteorological factors of carbon use efficiency(CUE)under the context of global warming are still not *** this study,MODIS-based public-domain data during 2000–2015 was used to analyze these aspects in the YRB,a large river basin with powerful ecological functions in ***-temporal variations of CUE in different sub-basins and land cover types were investigated and the correlations with potential driving meteorological factors were *** revealed that CUE in the YRB had strong spatiotemporal variability and varied remarkably in different land cover *** the whole YRB,the average CUE of vegetated land was 0.519,while the long-term change trend of CUE was *** the rising altitude,CUE generally showed an increasing trend until the altitude of 3900 m and then followed by a decreasing *** of grasslands was generally higher than that of croplands,and then forest *** inter-annual variation of CUE in the YRB is likely to be driven by precipitation as a strong positive partial correlation between the inter-annual variability of CUE and precipitation was observed in most of sub-basins and land cover types in the *** influence of temperature and relative humidity is also outstanding in certain regions and land cover *** findings are useful from the view point of carbon cycle and reasonable land cover management under the context of global warming.

关键词： Carbon use efficiency Climate variability MODIS Altitude Land cover type Precipitation

Structure kinematics of a transtensional basin:An example from the Linnan Subsag, Bohai Bay basin,Eastern China

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Geoscience Frontiers 2018年第3期9卷 917-929页

作者： Dong-Xiao Feng fu ye School of Earth Sciences and Resources China University of Geosciences (Beijing) Exploration and Development Research Institute of Shengli Oilfield Company SINOPEC Geophysics Research Institute of Shengli Oilfield Company SINOPEC

The Linnan subsag is a petroliferous, secondary tectonic unit of the Huimin sag that is located in the western part of the Jiyang depression in the Bohai Bay basin, eastern China. In this study, the authors calculated basin extensional rate and slipping displacement of boundary faults in the dip and strike directions, using seismic and drilling data. The evolution of the Linnan transtensional basin from the Eogene through the Quaternary is quantitatively described, and a dynamic model is established. The Linshan and Xiakou boundary faults of the Linnan subsag are used as a case study to describe a method to calculate the strike and dip slipping displacements of active faults under oblique extension. The results quantitatively illustrate the behavior of the Linnan subsag boundary faults over time. The Linnan subsag transtensional basin experienced four stages of evolution: weak extension during the Kongdian Formation, rapid extension and fault depression during the fourth member of the Shahejie Formation,intensive transtension and fault depression during the third member of the Shahejie Formation-Dongying Formation, and weakening fault depression during the Guantao Formation-Pingyuan *** results of this study provide further understanding of the processes of petroleum migration and accumulation in the region.

关键词： Transtensional basin Fault activity Quantitative calculation Basin evolution model Linnan subsag Bohai Bay basin

Dilatometric Analysis of Irreversible Volume Change during Phase Transformation in Pure Iron

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Journal of Iron and Steel Research International 2016年第8期23卷 828-833页

作者： Ren-jie ZHAO Jian-xun fu yu-yuan ZHU ye-jin YANG Yan-xin WU State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory Advanced Ferrometallurgy &School of Materials Science and Engineering Shanghai University

One assumption underlying the conventional dilatometric analysis based on the lever rule is that the volume of the specimen changes isotropically during phase transformation,which conflicts with the irreversible length change shown in actual *** contribution of this irreversible effect to the dilation data of pure iron upon heating and cooling was respectively quantified via conversion equations based on lattice parameters.A model considering the elastic strain and creep deformation was established for both the interpretation of the irreversible volume change and the discrepancy between the results measured by a dilatometer and a micrometer.

关键词： irreversible Transformation micrometer interpretation specimen lever length creep ferrite shrinkage