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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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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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AI-Powered Anomaly Detection and Cybersecurity in Healthcare IoT with Fog-Edge
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作者 Fatima Al-Quayed 《Computer Modeling in Engineering & Sciences》 2026年第1期1339-1372,共34页
The rapid proliferation of Internet of Things(IoT)devices in critical healthcare infrastructure has introduced significant security and privacy challenges that demand innovative,distributed architectural solutions.Thi... The rapid proliferation of Internet of Things(IoT)devices in critical healthcare infrastructure has introduced significant security and privacy challenges that demand innovative,distributed architectural solutions.This paper proposes FE-ACS(Fog-Edge Adaptive Cybersecurity System),a novel hierarchical security framework that intelligently distributes AI-powered anomaly detection algorithms across edge,fog,and cloud layers to optimize security efficacy,latency,and privacy.Our comprehensive evaluation demonstrates that FE-ACS achieves superior detection performance with an AUC-ROC of 0.985 and an F1-score of 0.923,while maintaining significantly lower end-to-end latency(18.7 ms)compared to cloud-centric(152.3 ms)and fog-only(34.5 ms)architectures.The system exhibits exceptional scalability,supporting up to 38,000 devices with logarithmic performance degradation—a 67×improvement over conventional cloud-based approaches.By incorporating differential privacy mechanisms with balanced privacy-utility tradeoffs(ε=1.0–1.5),FE-ACS maintains 90%–93%detection accuracy while ensuring strong privacy guarantees for sensitive healthcare data.Computational efficiency analysis reveals that our architecture achieves a detection rate of 12,400 events per second with only 12.3 mJ energy consumption per inference.In healthcare risk assessment,FE-ACS demonstrates robust operational viability with low patient safety risk(14.7%)and high system reliability(94.0%).The proposed framework represents a significant advancement in distributed security architectures,offering a scalable,privacy-preserving,and real-time solution for protecting healthcare IoT ecosystems against evolving cyber threats. 展开更多
关键词 AI-powered anomaly detection healthcare IoT fog computing CYBERSECURITY intrusion detection
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A Comparative Benchmark of Deep Learning Architectures for AI-Assisted Breast Cancer Detection in Mammography Using the MammosighTR Dataset:A Nationwide Turkish Screening Study(2016–2022)
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作者 Nuh Azginoglu 《Computer Modeling in Engineering & Sciences》 2026年第1期1151-1173,共23页
Breast cancer screening programs rely heavily on mammography for early detection;however,diagnostic performance is strongly affected by inter-reader variability,breast density,and the limitations of conven-tional comp... Breast cancer screening programs rely heavily on mammography for early detection;however,diagnostic performance is strongly affected by inter-reader variability,breast density,and the limitations of conven-tional computer-aided detection systems.Recent advances in deep learning have enabled more robust and scalable solutions for large-scale screening,yet a systematic comparison of modern object detection architectures on nationally representative datasets remains limited.This study presents a comprehensive quantitative comparison of prominent deep learning–based object detection architectures for Artificial Intelligence-assisted mammography analysis using the MammosighTR dataset,developed within the Turkish National Breast Cancer Screening Program.The dataset comprises 12,740 patient cases collected between 2016 and 2022,annotated with BI-RADS categories,breast density levels,and lesion localization labels.A total of 31 models were evaluated,including One-Stage,Two-Stage,and Transformer-based architectures,under a unified experimental framework at both patient and breast levels.The results demonstrate that Two-Stage architectures consistently outperform One-Stage models,achieving approximately 2%–4%higher Macro F1-Scores and more balanced precision–recall trade-offs,with Double-Head R-CNN and Dynamic R-CNN yielding the highest overall performance(Macro F1≈0.84–0.86).This advantage is primarily attributed to the region proposal mechanism and improved class balance inherent to Two-Stage designs.One-Stage detectors exhibited higher sensitivity and faster inference,reaching Recall values above 0.88,but experienced minor reductions in Precision and overall accuracy(≈1%–2%)compared with Two-Stage models.Among Transformer-based architectures,Deformable DEtection TRansformer demonstrated strong robustness and consistency across datasets,achieving Macro F1-Scores comparable to CNN-based detectors(≈0.83–0.85)while exhibiting minimal performance degradation under distributional shifts.Breast density–based analysis revealed increased misclassification rates in medium-density categories(types B and C),whereas Transformer-based architectures maintained more stable performance in high-density type D tissue.These findings quantitatively confirm that both architectural design and tissue characteristics play a decisive role in diagnostic accuracy.Overall,the study provides a reproducible benchmark and highlights the potential of hybrid approaches that combine the accuracy of Two-Stage detectors with the contextual modeling capability of Transformer architectures for clinically reliable breast cancer screening systems. 展开更多
关键词 Deep learning MAMMOGRAPHY breast cancer detection object detection BI-RADS classification
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Impact of Data Processing Techniques on AI Models for Attack-Based Imbalanced and Encrypted Traffic within IoT Environments
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作者 Yeasul Kim Chaeeun Won Hwankuk Kim 《Computers, Materials & Continua》 2026年第1期247-274,共28页
With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comp... With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy. 展开更多
关键词 Encrypted traffic attack detection data sampling technique AI-based detection IoT environment
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Deep Learning-Based Toolkit Inspection:Object Detection and Segmentation in Assembly Lines
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作者 Arvind Mukundan Riya Karmakar +1 位作者 Devansh Gupta Hsiang-Chen Wang 《Computers, Materials & Continua》 2026年第1期1255-1277,共23页
Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone t... Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone to errors and lacks consistency,emphasizing the need for a reliable and automated inspection system.Leveraging both object detection and image segmentation approaches,this research proposes a vision-based solution for the detection of various kinds of tools in the toolkit using deep learning(DL)models.Two Intel RealSense D455f depth cameras were arranged in a top down configuration to capture both RGB and depth images of the toolkits.After applying multiple constraints and enhancing them through preprocessing and augmentation,a dataset consisting of 3300 annotated RGB-D photos was generated.Several DL models were selected through a comprehensive assessment of mean Average Precision(mAP),precision-recall equilibrium,inference latency(target≥30 FPS),and computational burden,resulting in a preference for YOLO and Region-based Convolutional Neural Networks(R-CNN)variants over ViT-based models due to the latter’s increased latency and resource requirements.YOLOV5,YOLOV8,YOLOV11,Faster R-CNN,and Mask R-CNN were trained on the annotated dataset and evaluated using key performance metrics(Recall,Accuracy,F1-score,and Precision).YOLOV11 demonstrated balanced excellence with 93.0%precision,89.9%recall,and a 90.6%F1-score in object detection,as well as 96.9%precision,95.3%recall,and a 96.5%F1-score in instance segmentation with an average inference time of 25 ms per frame(≈40 FPS),demonstrating real-time performance.Leveraging these results,a YOLOV11-based windows application was successfully deployed in a real-time assembly line environment,where it accurately processed live video streams to detect and segment tools within toolkits,demonstrating its practical effectiveness in industrial automation.The application is capable of precisely measuring socket dimensions by utilising edge detection techniques on YOLOv11 segmentation masks,in addition to detection and segmentation.This makes it possible to do specification-level quality control right on the assembly line,which improves the ability to examine things in real time.The implementation is a big step forward for intelligent manufacturing in the Industry 4.0 paradigm.It provides a scalable,efficient,and accurate way to do automated inspection and dimensional verification activities. 展开更多
关键词 Tool detection image segmentation object detection assembly line automation Industry 4.0 Intel RealSense deep learning toolkit verification RGB-D imaging quality assurance
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YOLO-SDW: Traffic Sign Detection Algorithm Based on YOLOv8s Skip Connection and Dynamic Convolution
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作者 Qing Guo Juwei Zhang Bingyi Ren 《Computers, Materials & Continua》 2026年第1期1433-1452,共20页
Traffic sign detection is an important part of autonomous driving,and its recognition accuracy and speed are directly related to road traffic safety.Although convolutional neural networks(CNNs)have made certain breakt... Traffic sign detection is an important part of autonomous driving,and its recognition accuracy and speed are directly related to road traffic safety.Although convolutional neural networks(CNNs)have made certain breakthroughs in this field,in the face of complex scenes,such as image blur and target occlusion,the traffic sign detection continues to exhibit limited accuracy,accompanied by false positives and missed detections.To address the above problems,a traffic sign detection algorithm,You Only Look Once-based Skip Dynamic Way(YOLO-SDW)based on You Only Look Once version 8 small(YOLOv8s),is proposed.Firstly,a Skip Connection Reconstruction(SCR)module is introduced to efficiently integrate fine-grained feature information and enhance the detection accuracy of the algorithm in complex scenes.Secondly,a C2f module based on Dynamic Snake Convolution(C2f-DySnake)is proposed to dynamically adjust the receptive field information,improve the algorithm’s feature extraction ability for blurred or occluded targets,and reduce the occurrence of false detections and missed detections.Finally,the Wise Powerful IoU v2(WPIoUv2)loss function is proposed to further improve the detection accuracy of the algorithm.Experimental results show that the average precision mAP@0.5 of YOLO-SDW on the TT100K dataset is 89.2%,and mAP@0.5:0.95 is 68.5%,which is 4%and 3.3%higher than the YOLOv8s baseline,respectively.YOLO-SDW ensures real-time performance while having higher accuracy. 展开更多
关键词 Traffic sign detection YOLOv8 object detection deep learning
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