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Pressure distribution imaging through wide-field optical detected magnetic resonance
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作者 Chaofan Lv Kai Ma +9 位作者 Feihu Lei Yidan Qu Qilong Wu Wuyou Zhang Yingjie Zhang Huihui Yu Xuanming Shen Yuan Zhang Xigui Yang Chongxin Shan 《Chinese Physics B》 2025年第8期293-300,共8页
Non-hydrostatic stress plays a significant role in shaping the properties of materials under compression.High-pressure effects such as yielding deformation,phase transitions,and volume contraction can alter the pressu... Non-hydrostatic stress plays a significant role in shaping the properties of materials under compression.High-pressure effects such as yielding deformation,phase transitions,and volume contraction can alter the pressure distribution within the pressure chamber.However,due to the inherent size limitation of the diamond anvil cell(DAC),in situ high-pressure studies usually assume a hydrostatic environment,equaling the pressure of samples to a pressure calibrator inside the chamber.Accurately imaging pressure distribution within the DAC chamber remains challenging,particularly as the material undergoes phase transitions.Here,we present a method for mapping pressure distribution with high spatial resolution using wide-field optically detected magnetic resonance(ODMR)of nanodiamonds.The pressure gradients during the highpressure transition of zinc oxide(ZnO)were compared using both the multiple rubies technique and wide-field ODMR.The latter technique demonstrated superior spatial resolution,easier operation,and more detailed information.These results highlight the potential of wide-field ODMR as a powerful tool for precise pressure sensing,particularly in studies involving non-hydrostatic pressure conditions. 展开更多
关键词 optically detected magnetic resonance(ODMR) high-pressure phase transition ZNO
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A study of the strong pulses detected from PSR B0656+14 using the Urumqi 25-m radio telescope at 1540 MHz 被引量:2
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作者 Guo-Cun Tao Ali Esamdin +3 位作者 Hui-Dong Hu Mao-Fei Qian Jing Li Na Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第12期1649-1654,共6页
We report on the properties of strong pulses from PSR B0656+14 by analyzing the data obtained using the Urumqi 25-m radio telescope at 1540 MHz from August 2007 to September 2010.In 44 h of observational data,a total... We report on the properties of strong pulses from PSR B0656+14 by analyzing the data obtained using the Urumqi 25-m radio telescope at 1540 MHz from August 2007 to September 2010.In 44 h of observational data,a total of 67 pulses with signal-to-noise ratios above a 5σthreshold were detected.The peak flux densities of these pulses are 58 to 194 times that of the average profile,and their pulse energies are 3 to 68 times that of the average pulse.These pulses are clustered around phases about 5-ahead of the peak of the average profile.Compared with the width of the average profile,they are relatively narrow,with the full widths at half-maximum ranging from 0.28 ° to 1.78 °.The distribution of pulse-energies follows a lognormal distribution.These sporadic strong pulses detected from PSR B0656+14 have different characteristics from both typical giant pulses and its regular pulses. 展开更多
关键词 stars:neutron-pulsars-pulsars:individual(B0656+14)Options: Encrypt Page Allow Cookies Remove Scripts Remove Objects 收藏本站首页期刊全文库学位论文库会议论文库学术百科吾喜杂志工具书优先出版注册|登录|我的账户基础科学|工程科技I辑|工程科技II辑|医药卫生科技|信息科技|农业科技|哲学与人文科学|社会科学I辑|社会科学II辑|经济管理高级搜索: 用" stars neutron-pulsars—pulsars "到知网平台检索 点击这里搜索更多...《Research in Astronomy and Astrophysics》 2012年12期 加入收藏 获取最新 A study of the strong pulses detected from PSR B0656+14 using the Urumqi 25-m radio telescope at 1540 MHzAli Esamdin 【摘要】: We report on the properties of strong pulses from PSR B0656+14 by analyzing the data obtained using the Urumqi 25-m radio telescope at 1540 MHz from August 2007 to September 2010.In 44 h of observational data a total of 67 pulses with signal-to-noise ratios above a 5σthreshold were detected.The peak flux densities of these pulses are 58 to 194 times that of the average profile and their pulse energies are 3 to 68 times that of the average pulse.These pulses are clustered around phases about 5-ahead of the peak of the average profile.Compared with the width of the average profile they are relatively narrow with the full widths at half-maximum ranging from 0.28 ° to 1.78 °.The distribution of pulse-energies follows a lognormal distribution.These sporadic strong pulses detected from PSR B0656+14 have different characteristics from both typical giant pulses and its regular pulses.【作者单位】 Xinjiang
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TOPOLOGICAL STRUCTURE OF THE SINGULAR POINTS OF THE THIRD ORDER PHASE LOCKED LOOP EQUATIONS WITH THE CHARACTER OF DETECTED PHASE BEING g(φ)=(1+k)sinφ/(1+kcosφ)
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作者 金均 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第9期883-889,共7页
In this paper, we study the topological structure of the singular points of the third order phase locked loop equations with the character of detected phase being g(?) =(1+k)sin?/1+kcos?.
关键词 singular point topological structure character of detected phase exponentially asymptotically stable Jordan form
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Quantum Spin Liquid Phase in the Shastry–Sutherland Model Detected by an Improved Level Spectroscopic Method
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作者 Ling Wang Yalei Zhang Anders W.Sandvik 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第7期105-116,共12页
We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps betwe... We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps between states with different quantum numbers. The crossing points of some of the relative(composite) gaps have much weaker finite-size drifts than the normally used gaps defined only with respect to the ground state, thus allowing precise determination of quantum critical points even with small clusters. Our results support the picture of a spin liquid phase intervening between the well-known plaquette-singlet and antiferromagnetic ground states, with phase boundaries in almost perfect agreement with a recent density matrix renormalization group study, where much larger cylindrical lattices were used [J. Yang et al., Phys. Rev. B 105, L060409(2022)]. The method of using composite low-energy gaps to reduce scaling corrections has potentially broad applications in numerical studies of quantum critical phenomena. 展开更多
关键词 red SSM Sutherland Model detected by an Improved Level Spectroscopic Method Quantum Spin Liquid Phase in the Shastry Model
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Analysis of Detected Avalanches Using Meteorological Data of Nearby Monitoring Stations in Ischgl, Austria
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作者 Lisa Jobstl Arnold Studeregger +2 位作者 Amulf Wurzer Daniel Stock Richard Koschuh 《Journal of Environmental Science and Engineering(B)》 2014年第2期87-90,共4页
A set of detected avalanches from January to April 2012 on a hillside southeast of lschgl, Austria is given. The avalanches are off-the-cut or caused by blast. The meteorological data of two monitoring stations nearby... A set of detected avalanches from January to April 2012 on a hillside southeast of lschgl, Austria is given. The avalanches are off-the-cut or caused by blast. The meteorological data of two monitoring stations nearby the hillside are taken for analysing the weather situation. The meteorological parameters air temperature, wind intensity and wind speed, relative humidity, precipitation and snow depth are investigated for similarities short before and during an avalanche. The avalanches are grouped into three categories and meteorological characteristics are found for each category. Thereby the avalanche hazard for the observed hillside is better assessed and an infrastructure safety by avalanche control due to concerted avalanche blasts is more effective. The result of the analysis shows three kinds of hazard weather conditions, which increase the avalanche hazard: warm air temperatures cause a settlement of the snow pack, but in the beginning of the process a weakening in the snow pack happens. Rapidly decreasing of the air temperature cause cracks in the snow pack and the combination of fresh snow and strong wind speed leads to accumulation of snow on sheltered slopes. 展开更多
关键词 detected avalanches meteorological weather stations avalanche danger snow pack
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Iron-Mediated Oxidative DNA Damage Detected by Fluorometric Analysis of DNA Unwinding in Isolated Rat Liver Nuclei
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作者 SAURA C.SAHU MELISSA C.WASHINGTON 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1991年第3期232-241,共10页
Studies were performed to determine the extent of nuclear DNA degradation induced by iron, iron-ascorbate, or iron-bleomycin under aerobic conditions in a model system using isolated rat liver nuclei. The effects of f... Studies were performed to determine the extent of nuclear DNA degradation induced by iron, iron-ascorbate, or iron-bleomycin under aerobic conditions in a model system using isolated rat liver nuclei. The effects of five antioxidants (catalase, superoxide dismutase, dimethyl sulfoxide, glutathione and diallyl sulfide) on this oxidative nuclear damage were also investigated. At the 0.05 level for statistical significance, iron induced concentration-dependent DNA degradation, and this effect was enhanced by ascorbate and bleomycin. The antioxidants catalase, dimethyl sulfoxide, and diallyl sulfide significantly reduced the iron-ascorbate-induced DNA damage, whereas superoxide dismutase and dimethyl sulfoxide significantly reduced iron-bleomycin-induced damage. Glutathione significantly increased the iron-bleomycin-induced DNA damage. These results suggest that the reactive oxygen species generated by iron, iron-ascorbate, and iron-bleomycin are responsible for the DNA strand breaks in isolated rat liver nuclei. 展开更多
关键词 Iron-Mediated Oxidative DNA Damage detected by Fluorometric Analysis of DNA Unwinding in Isolated Rat Liver Nuclei DNA
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Super Large-scaled Bauxite Deposit Detected in Guizhou Province
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《China's Refractories》 CAS 2013年第3期11-11,共1页
Recently, the Bureau of Geology and Mineral Exploration and Development of Guizhou Province detected an about 140 million tons resource in Zheng'an County, 100 million tons of which was bauxite. This is the second de... Recently, the Bureau of Geology and Mineral Exploration and Development of Guizhou Province detected an about 140 million tons resource in Zheng'an County, 100 million tons of which was bauxite. This is the second detected super large-scaled bauxite deposit after the Dazhuyuan bauxite deposit in Wuchuan County. 展开更多
关键词 Super Large-scaled Bauxite Deposit detected in Guizhou Province
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A case of pulmonary arteriovenous fistula detected by contrast transthoracic echocardiography combined with CTA
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作者 庄颖珠 梁春香 +1 位作者 郝哲 晋群 《South China Journal of Cardiology》 CAS 2016年第4期256-260,共5页
Pulmonary arteriovenous fistula (PAVF) is a kind of malformation resulting in the abnormal vessels between pulmonary artery and pulmonary vein. Part of pulmonary arterial blood flows into pulmonary veins through the... Pulmonary arteriovenous fistula (PAVF) is a kind of malformation resulting in the abnormal vessels between pulmonary artery and pulmonary vein. Part of pulmonary arterial blood flows into pulmonary veins through the fistula and then arrives at left atrium, inducing the right-to-left shunt. Moreover, the emboli and bacteria can also flow directly through the PAVF into systemic circulation, which can cause thromboembolic diseases such as stroke. 展开更多
关键词 TTE A case of pulmonary arteriovenous fistula detected by contrast transthoracic echocardiography combined with CTA CASE
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Reconstruction of vector static magnetic field by different axial NV centers using continuous wave optically detected magnetic resonance in diamond 被引量:1
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作者 Jian-Feng Ye Zheng Jiao +3 位作者 Kun Ma Zhi-Yong Huang Hai-Jiang Lv Feng-Jian Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第4期337-341,共5页
We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy(NV) sensors with corresponding different NV symmetry axes in a bulk d... We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy(NV) sensors with corresponding different NV symmetry axes in a bulk diamond. By means of optical detection of the magnetic resonance(ODMR) techniques, our experiment employs the continuous wave(CW) to monitor resonance frequencies and it extracts the information of the detected field strength and polar angles with respect to each NV frame of reference. Finally, the detected magnetic field relative to a fixed laboratory reference frame was reconstructed from the information acquired by the multi-NV sensor. 展开更多
关键词 DIAMOND defect optical detection magnetic resonance MAGNETOMETER
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Is every microorganism detected in the intensive care unit a nosocomial infection?Isn’t prevention more important than detection? 被引量:1
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作者 Fatma Yildirim Irem Karaman Mehmet Yildirim 《World Journal of Clinical Cases》 SCIE 2022年第20期7184-7186,共3页
The present letter to the editor is related to the study entitled“Multidrug-resistant organisms in intensive care units and logistic analysis of risk factors.”Not every microorganism grown in samples taken from crit... The present letter to the editor is related to the study entitled“Multidrug-resistant organisms in intensive care units and logistic analysis of risk factors.”Not every microorganism grown in samples taken from critically ill patients can be considered as an infectious agent.Accurate and adequate information about nosocomial infections is essential in introducing effective prevention programs in hospitals.Therefore,the development and implementation of care bundles for frequently used medical devices and invasive treatment devices(e.g.,intravenous catheters and invasive ventilation),adequate staffing not only for physicians,nurses,and other medical staff but also for housekeeping staff,and infection surveillance and motivational feedback are key points of infection prevention in the intensive care unit. 展开更多
关键词 Critical care PREVENTION Intensive care unit Nosocomial infection DETECTION
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Ocular surface heat effects on ocular hemodynamics detected by real-time measuring device
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作者 Ting-Ting Li Guang-Bin Shao +4 位作者 Yu-Long Jiang Jing-Xuan Wang Xin-Rong Zhou Min Ren Long-Qiu Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第12期1902-1908,共7页
AIM: To investigate the ocular hemodynamic effects of applying a hot compress to the eye.METHODS: The right eyes of five New Zealand white rabbits, both male and female, were hot-compressed for 18 min. An independentl... AIM: To investigate the ocular hemodynamic effects of applying a hot compress to the eye.METHODS: The right eyes of five New Zealand white rabbits, both male and female, were hot-compressed for 18 min. An independently designed novel ocular contacttype temperature measuring device was used to measure the ocular surface temperature before and after the heating. Relevant retrobulbar hemodynamic parameters such as peak systolic velocity(PSV), end diastolic velocity(EDV), and resistance index(RI) of each of the central retinal artery(CRA), long posterior ciliary artery(LPCA), and ophthalmic artery(OA), as well as the mean velocity(V_m) of the central retinal vein(CRV), were measured using a color Doppler flow imaging(CDFI) technique and expressed as mean values with standard deviation(mean±SD). A statistical analysis was conducted based on a paired t-test and the Wilcoxon signed-rank test. RESULTS: The employed real-time temperature measuring device was able to accurately measure ocular surface temperature during the hot-compress process. The temperature increased after the hot compress was applied. Analysis showed that the PSV and EDV values of the CRA and LPCA significantly increased after the application of the hot compress, as did the V_m of the CRV. There were no significant changes in the EDV of the OA nor the RI of each artery. CONCLUSION: This experiment, which is the first of its kind, confirms that the retrobulbar blood flow velocities can increase upon heating the ocular surface. This simple method may be useful in the future. 展开更多
关键词 ocular hemodynamics ocular surface heating temperature detection device color Doppler flow imaging
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Structural Mechanics Analysis Using an FE-Mesh Adaption to Real, 3D Surface Detected Geometry Data
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作者 Sebastian Katona Michael Koch +1 位作者 Tobias C. Spruegel Sandro Wartzack 《Journal of Mechanics Engineering and Automation》 2015年第7期387-394,共8页
Within today's product development process, various FE-simulations (finite element) for the functional validation of the desired characteristics are made to avoid expensive testing with real components. Those simul... Within today's product development process, various FE-simulations (finite element) for the functional validation of the desired characteristics are made to avoid expensive testing with real components. Those simulations are performed with great effort for discretization, use of simulations conditions, like taking different non-linearities (i.e., material behavior, etc.) into account, to create meaningful results. Despite knowing the effects of deformations occurring during the production processes, always the non-deformed design model of a CAD-system (computer aided design) is used for the FE-simulations. It seems rather doubtful that further refinement of simulation methods makes sense, if the real manufactured geometry of the component is not considered for in the simulation. For an efficient exploit of the potential of simulation methods, an approach has been developed which offers a geometry model for simulation based on the existing CAD-model but with integrated production deviations as soon as a first prototype is at hand by adapting the FE-mesh to the real, 3D surface detected geometry. 展开更多
关键词 FEA (finite element analysis) PREPROCESSING simulation 3D surface detection RE (reverse engineering)
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Effects of Standing Time during Pretreatment on the Nitrite Concentration Detected by Spectrophotometric Method
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作者 Yingfei Zeng Juan Hu +2 位作者 Xianglong Bian Qianfeng Xia Tingwei Hu 《Journal of Materials Science and Chemical Engineering》 2024年第2期73-83,共11页
Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a... Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a great influence on the concentration of nitrite tested by spectrophotometric method. In this context, three kinds of food samples are prepared, including canned mustard, canned fish and home-made pickled water. A series of standing times are placed during the sample pretreatments and the corresponding nitrite contents in these samples are detected by spectrophotometric method based on N-ethylenediamine dihydrochloride. This study aims to find out a reasonable standing time during the pretreatment of food sample, providing influence factor for precise detection of nitrite. 展开更多
关键词 Standing Time Spectrophotometric Method Nitrite Detection
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Exploring the depth of the maize canopy LAI detected by spectroscopy based on simulations and in situ measurements
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作者 Jinpeng Cheng Jiao Wang +9 位作者 Dan Zhao Fenghui Duan Qiang Wu Yongliang Lai Jianbo Qi Shuping Xiong Hongbo Qiao Xinming Ma Hao Yang Guijun Yang 《Plant Phenomics》 2025年第3期323-336,共14页
The vertical distribution of leaves plays a crucial role in the growth process of maize.Understanding the vertical spectral characteristics of maize leaves is crucial for monitoring their growth.However,accurate estim... The vertical distribution of leaves plays a crucial role in the growth process of maize.Understanding the vertical spectral characteristics of maize leaves is crucial for monitoring their growth.However,accurate estimation of the vertical distribution of leaf area remains a significant challenge in practical investigations.To address this,we used a 3D RTM to simulate the layered canopy spectra of maize,revealing the impact of canopy structure on remote sensing penetration depth across different growth stages and planting densities.The results of this study revealed differences in detection depth across growth stages.During the early growth stage,the depth was concentrated in the bottom 1 to 3 leaves of the canopy,reaching 1 to 4 leaves at the ear stage and 1 to 7 leaves during the grain-filling stage.The planting density had a notable effect on the detection depth at the bottom of the canopy.Moreover,compared with the other spectral bands,the near-infrared spectral range exhibited greater sensitivity to density variations.In terms of LAI inversion,a FuseBell-Hybrid model was constructed.We analyzed VIs across different planting density and canopy structural scenarios and found that compared with lower layers,increased density reduced the relative change rate in the upper leaf layers.The sensitivity patterns differed between plant architectures:VIred exhibited density-dependent sensitivity,with distinct responses be-tween plant types,and MTVI2 demonstrated optimal performance for mid-canopy monitoring.This study highlights the influence of the heterogeneous structural characteristics of maize canopies on remote sensing detection depth during different phenological stages,providing theoretical support for enhancing multilayer crop monitoring in precision agriculture. 展开更多
关键词 3D radiative transfer model Vertical LAI distribution UAV remote sensing MAIZE Detection depth
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中国丹顶鹤迁徙路线湿地景观格局演化模式及其驱动因素
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作者 尹梓烨 那晓东 《生态学报》 北大核心 2026年第4期1800-1814,共15页
探究丹顶鹤迁徙路线上的湿地景观格局演化模式及驱动因素,有利于构建促进物种迁徙的生态廊道、科学制定湿地修复策略、维护湿地生态系统稳定。以丹顶鹤迁徙路线上的湿地为对象,获取1990—2020年共七期土地利用/覆被数据,基于改进过后的... 探究丹顶鹤迁徙路线上的湿地景观格局演化模式及驱动因素,有利于构建促进物种迁徙的生态廊道、科学制定湿地修复策略、维护湿地生态系统稳定。以丹顶鹤迁徙路线上的湿地为对象,获取1990—2020年共七期土地利用/覆被数据,基于改进过后的景观格局状态与演化识别模型(SEDM)研究湿地格局演化模式的时空分布特征,并利用地理探测器分析其驱动因素。结果表明:(1)1990—2015年间湿地面积减少了7994km^(2),湿地萎缩严重,大量湿地转化为耕地、人工表面。2015—2020年湿地面积增加,而转入湿地的主要类型为耕地、水域和林地。(2)湿地景观格局的演化具有明显的阶段性特征,1990—2000年间湿地格局演化以破碎类型为主,收缩与减少模式占主导;2000—2015年湿地面积减少趋势放缓,发生演化的格网数量显著减少,湿地格局演化模式由减少模式向新增模式过渡;2015—2020年湿地景观格局演化以扩张类型为主,增加与新增演化模式为主导,湿地得到有效恢复。(3)湿地格局演化频数较高的区域集中在东北松嫩平原、三江平原、黄河三角洲与盐城滨海地区,气温、降水和耕地对湿地格局演化影响最为显著。其中在东北地区的松嫩和三江平原湿地格局演化频繁主要受气候变化、耕地扩张影响,而黄河三角洲和盐城湿地格局演化主要受人类活动的影响。总体来看,气候变化虽然是湿地格局演化的关键因素,但湿地格局演化从破碎转向扩张模式,主要是受人为因素的驱动。 展开更多
关键词 湿地 the state-and-evolution detection models(SEDM)模型 景观格局演化模式 地理探测器 丹顶鹤
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Stuxnet detected, Pc breaks down 被引量:1
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作者 Xudong Wu 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第11期1202-1203,共2页
Polycomb group (PcG) proteins were originally identified in Drosophila. They generally maintain gene silencing by forming multimeric complexes. Two main complexes, namely Polycomb repressive complex 2 (PRC2) and P... Polycomb group (PcG) proteins were originally identified in Drosophila. They generally maintain gene silencing by forming multimeric complexes. Two main complexes, namely Polycomb repressive complex 2 (PRC2) and PRC1, have been described. PRC2 methylates histone H3 on lysine 27 (H3K27). PRC1, mainly composed of Polycomb (Pc), Polyhomeotic (Ph), Posterior sex combs (Psc) and dRing/Sce, has been shown to directly compact chromatin in vitro. 展开更多
关键词 PRC Stuxnet detected UBL Pc breaks down
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Global-local feature optimization based RGB-IR fusion object detection on drone view 被引量:1
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作者 Zhaodong CHEN Hongbing JI Yongquan ZHANG 《Chinese Journal of Aeronautics》 2026年第1期436-453,共18页
Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still st... Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still struggle to deal with the complex and changing scenarios captured by drones,mainly due to two reasons:(A)RGB-IR fusion detectors are susceptible to inferior inputs that degrade performance and stability.(B)RGB-IR fusion detectors are susceptible to redundant features that reduce accuracy and efficiency.In this paper,an innovative RGB-IR fusion detection framework based on global-local feature optimization,named GLFDet,is proposed to improve the detection performance and efficiency of drone-captured objects.The key components of GLFDet include a Global Feature Optimization(GFO)module,a Local Feature Optimization(LFO)module and a Channel Separation Fusion(CSF)module.Specifically,GFO calculates the information content of the input image from the frequency domain and optimizes the features holistically.Then,LFO dynamically selects high-value features and filters out low-value features before fusion,which significantly improves the efficiency of fusion.Finally,CSF fuses the RGB and IR features across the corresponding channels,which avoids the rearrangement of the channel relationships and enhances the model stability.Extensive experimental results show that the proposed method achieves the best performance on three popular RGB-IR datasets Drone Vehicle,VEDAI,and LLVIP.In addition,GLFDet is more lightweight than other comparable models,making it more appealing to edge devices such as drones.The code is available at https://github.com/lao chen330/GLFDet. 展开更多
关键词 Object detection Deep learning RGB-IR fusion DRONES Global feature Local feature
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基于DETR的视频时刻检索方法综述
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作者 高杜娟 吴媛媛 +3 位作者 林文龙 谢天圻 嘉昊阳 冯昭天 《计算机工程与应用》 北大核心 2026年第5期18-38,共21页
视频时刻检索旨在根据自然语言查询精确定位视频中的特定片段,是视频理解下的重要任务之一。传统方法依赖冗余候选生成和手工特征设计,难以兼顾检索精度与计算效率。近年来,基于Detection Transformer(DETR)的端到端方法借助可学习查询... 视频时刻检索旨在根据自然语言查询精确定位视频中的特定片段,是视频理解下的重要任务之一。传统方法依赖冗余候选生成和手工特征设计,难以兼顾检索精度与计算效率。近年来,基于Detection Transformer(DETR)的端到端方法借助可学习查询机制和直接回归预测策略,简化了框架的同时提升了检索性能。对DETR在视频时刻检索中的关键技术进展进行了系统综述,回顾了DETR模型的基础原理及其在该任务中的适配改进;对DETR的模型框架结构的优化研究方法进行了分类,细分为基于输入建模的特征增强、基于跨模态对齐的交互机制优化以及基于解码器结构与时刻回归机制这三个优化方向。对主流方法进行了系统梳理与检索精度比较;结合实验结果,分析了不同优化策略对模型性能的影响,并总结了各方法在主流数据集上的表现差异。最后,针对面向真实应用场景的泛化、跨模态交互走向语义整合机制以及面向开放领域与个性化检索的扩展这三个未来发展方向进行了讨论展望,为后续研究提供理论参考与实践指导。 展开更多
关键词 视频时刻检索 Detection Transformer(DETR) 深度学习
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Deep Feature-Driven Hybrid Temporal Learning and Instance-Based Classification for DDoS Detection in Industrial Control Networks
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作者 Haohui Su Xuan Zhang +2 位作者 Lvjun Zheng Xiaojie Shen Hua Liao 《Computers, Materials & Continua》 2026年第3期708-733,共26页
Distributed Denial-of-Service(DDoS)attacks pose severe threats to Industrial Control Networks(ICNs),where service disruption can cause significant economic losses and operational risks.Existing signature-based methods... Distributed Denial-of-Service(DDoS)attacks pose severe threats to Industrial Control Networks(ICNs),where service disruption can cause significant economic losses and operational risks.Existing signature-based methods are ineffective against novel attacks,and traditional machine learning models struggle to capture the complex temporal dependencies and dynamic traffic patterns inherent in ICN environments.To address these challenges,this study proposes a deep feature-driven hybrid framework that integrates Transformer,BiLSTM,and KNN to achieve accurate and robust DDoS detection.The Transformer component extracts global temporal dependencies from network traffic flows,while BiLSTM captures fine-grained sequential dynamics.The learned embeddings are then classified using an instance-based KNN layer,enhancing decision boundary precision.This cascaded architecture balances feature abstraction and locality preservation,improving both generalization and robustness.The proposed approach was evaluated on a newly collected real-time ICN traffic dataset and further validated using the public CIC-IDS2017 and Edge-IIoT datasets to demonstrate generalization.Comprehensive metrics including accuracy,precision,recall,F1-score,ROC-AUC,PR-AUC,false positive rate(FPR),and detection latency were employed.Results show that the hybrid framework achieves 98.42%accuracy with an ROC-AUC of 0.992 and FPR below 1%,outperforming baseline machine learning and deep learning models.Robustness experiments under Gaussian noise perturbations confirmed stable performance with less than 2%accuracy degradation.Moreover,detection latency remained below 2.1 ms per sample,indicating suitability for real-time ICS deployment.In summary,the proposed hybrid temporal learning and instance-based classification model offers a scalable and effective solution for DDoS detection in industrial control environments.By combining global contextual modeling,sequential learning,and instance-based refinement,the framework demonstrates strong adaptability across datasets and resilience against noise,providing practical utility for safeguarding critical infrastructure. 展开更多
关键词 DDoS detection transformer BiLSTM K-Nearest Neighbor representation learning network security intrusion detection real-time classification
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