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Evaluating the Effect of Tillage on Carbon Sequestration Using the Minimum Detectable Difference Concept 被引量:13
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作者 X. M. YANG C. F. DRURY +1 位作者 M. M. WANDER B. D. KAY 《Pedosphere》 SCIE CAS CSCD 2008年第4期421-430,共10页
Three long-term field trials in humid regions of Canada and the USA were used to evaluate the influence of soil depth and sample numbers on soil organic carbon (SOC) sequestration in no-tillage (NT) and moldboard plow... Three long-term field trials in humid regions of Canada and the USA were used to evaluate the influence of soil depth and sample numbers on soil organic carbon (SOC) sequestration in no-tillage (NT) and moldboard plow (MP) corn (Zea mays L.) and soybean (Glycine max L.) production systems. The first trial was conducted on a Maryhill silt loam (Typic Hapludalf) at Elora, Ontario, Canada, the second on a Brookston clay loam (Typic Argiaquoll) at Woodslee, Ontario, Canada, and the third on a Thorp silt loam (Argiaquic Argialboll) at Urbana, Illinois, USA. No-tillage led to significantly higher SOC concentrations in the top 5 cm compared to MP at all 3 sites. However, NT resulted in significantly lower SOC in sub-surface soils as compared to MP at Woodslee (10-20 cm, P = 0.01) and Urbana (20-30 cm, P < 0.10). No-tillage had significantly more SOC storage than MP at the Elora site (3.3 Mg C ha-1) and at the Woodslee site (6.2 Mg C ha-1) on an equivalent mass basis (1350 Mg ha-1 soil equivalent mass). Similarly, NT had greater SOC storage than MP at the Urbana site (2.7 Mg C ha-1) on an equivalent mass basis of 675 Mg ha-1 soil. However, these differences disappeared when the entire plow layer was evaluated for both the Woodslee and Urbana sites as a result of the higher SOC concentrations in MP than in NT at depth. Using the minimum detectable difference technique, we observed that up to 1500 soil sample per tillage treatment comparison will have to be collected and analyzed for the Elora and Woodslee sites and over 40 soil samples per tillage treatment comparison for the Urbana to statistically separate significant differences in the SOC contents of sub-plow depth soils. Therefore, it is impracticable, and at the least prohibitively expensive, to detect tillage-induced differences in soil C beyond the plow layer in various soils. 展开更多
关键词 carbon sequestration minimum detectable difference moldboard plow NO-TILLAGE soil depth
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Effective path planning method for low detectable aircraft 被引量:2
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作者 Wang Lingxiao Zhou Deyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期784-789,共6页
To utilizing the characteristic of radar cross section (RCS) of the low detectable aircraft, a special path planning algorithm to eluding radars by the variable RCS is presented. The algorithm first gives the RCS ch... To utilizing the characteristic of radar cross section (RCS) of the low detectable aircraft, a special path planning algorithm to eluding radars by the variable RCS is presented. The algorithm first gives the RCS changing model of low detectable aircraft, then establishes a threat model of a ground-based air defense system according to the relations between RCS and the radar range coverage. By the new cost functions of the flight path, which consider both factors of the survival probability and the distance of total route, this path planning method is simulated based on the Dijkstra algorithm, and the planned route meets the flight capacity constraints. Simulation results show that using the effective path planning algorithm, the low detectable aircraft can give full play to its own advantage of stealth to achieve the purpose of silent penetration. 展开更多
关键词 path planning low detectable aircraft radar scattering cross section threat lever cost function
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Investigating the minimum detectable activity concentration and contributing factors in airborne gamma-ray spectrometry 被引量:2
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作者 Yi Gu Kun Sun +6 位作者 Liang-Quan Ge Yuan-Dong Li Qing-Xian Zhang Xuan Guan Wan-Chang Lai Zhong-Xiang Lin Xiao-Zhong Han 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第10期30-38,共9页
In this study,the theory of minimum detectable activity concentration(MDAC)for airborne gamma-ray spectrometry(AGS)was derived,and the relationship between the MDAC and the intrinsic effi-ciency of a scintillation cou... In this study,the theory of minimum detectable activity concentration(MDAC)for airborne gamma-ray spectrometry(AGS)was derived,and the relationship between the MDAC and the intrinsic effi-ciency of a scintillation counter,volume,and energy res-olution of scintillation crystals,and flight altitude of an aircraft was investigated.To verify this theory,experi-mental devices based on NaI and CeBr 3 scintillation counters were prepared,and the potassium,uranium,and thorium contents in calibration pads obtained via the stripping ratio method and theory were compared.The MDACs of AGS under different conditions were calculated and analyzed using the proposed theory and the Monte Carlo method.The relative errors found via a comparison of the experimental and theoretical results were less than 4%.The theory of MDAC can guide the work of AGS in probing areas with low radioactivity. 展开更多
关键词 Airborne gamma-ray spectrometry(AGS) Minimum detectable activity concentration(MDAC) Sensitivity
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A New Solution to Detectable Byzantine Agreement Problem
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作者 QIN Su-Juan WEN Qiao-Yan +1 位作者 MENG Luo-Ming ZHU Fu-Chen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1013-1015,共3页
We present a new quantum protocol for solving detectable Byzantine agreement problem between threeparties by employing one quantum key distribution protocol.The protocol is suggested by a special four-qubit entangleds... We present a new quantum protocol for solving detectable Byzantine agreement problem between threeparties by employing one quantum key distribution protocol.The protocol is suggested by a special four-qubit entangledstate instead of singlet states,which shows that singlet states are not necessary to achieve detectable Byzantine agreement. 展开更多
关键词 quantum protocol detectable Byzantine agreement entangled state
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Clinical Signifi cance of Angiographically Detectable Neovascularity in Patients with Cardiac Myxoma
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作者 Xiaofan Peng Yichao Xiao +7 位作者 Yanan Guo Zhaowei Zhu Liyan Liao Xiaobo Liao Xinqun Hu Zhenfei Fang Xuping Li Shenghua Zhou 《Cardiovascular Innovations and Applications》 2021年第4期99-108,共10页
Background:Myxomas are the most common primary cardiac tumors.Angiographically detectable neovascularity(ADN)of myxoma is increasingly being reported as a result of the use of coronary angiography(CAG)to detect corona... Background:Myxomas are the most common primary cardiac tumors.Angiographically detectable neovascularity(ADN)of myxoma is increasingly being reported as a result of the use of coronary angiography(CAG)to detect coronary artery disease.However,the clinical signifi cance of these fi ndings is not fully understood.Methods:We enrolled 59 patients with cardiac myxoma who also underwent CAG between January 2013 and October 2018.Patients were followed up for a mean of 28.9 months(range 1-69 months).The clinical features,echocardiography measurements,pathological examination fi ndings,CAG results,and outcomes during follow-up were compared between patients with ADN and patients without ADN.Results:ADN was found in 25 patients(42.4%).The arteries feeding the ADN included the right coronary artery(n=15),the left circumfl ex coronary artery(n=7),and both arteries(n=3).The patients with ADN had a higher proportion of eosinophils(3.2%vs.2.2%,P=0.03)and higher low-density lipoprotein cholesterol level(2.7 mmol/L vs.2.2 mmol/L,P=0.02).Myxoma pedicles were more likely to be located in the interatrial septum in patients with ADN(96%vs.73.5%,P=0.02).No signifi cant correlation was observed between the groups in clinical manifestations,atrial arrhythmia,myxoma size,cardiac chamber size,left ventricular ejection fraction,and the prevalence of complication with coronary artery disease[16%in the ADN group(n=4)vs.20.6%in the non-ADN group(n=7),P=0.66].However,patients with ADN tended to have a lower incidence of major adverse cardiac and cerebrovascular events on long-term follow-up(0%vs.14.7%,P=0.07).Conclusion:CAG-detected ADN in patients with cardiac myxoma is associated with a borderline lower rate of major adverse cardiac and cerebrovascular events. 展开更多
关键词 Cardiac myxomas coronary angiography angiographically detectable neovascularity major adverse cardiac and cerebrovascular events
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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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Minimum detectable activity for NaI(Tl) airborne γ-ray spectrometry based on Monte Carlo simulation 被引量:3
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作者 GONG ChunHui ZENG GuoQiang +2 位作者 GE LiangQuan TANG Xiaobin TAN ChengJun 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第9期1840-1845,共6页
The determination of the effective minimum detectable activity (MDA) of radionuclides by a detection system plays an im- portant role in environmental radiation monitoring. In this study, the responses of an NaI(TI... The determination of the effective minimum detectable activity (MDA) of radionuclides by a detection system plays an im- portant role in environmental radiation monitoring. In this study, the responses of an NaI(TI) airborne γ ray spectrometry (AGRS) system to different radionuclides (137Cs and 131I) were investigated using the Monte Carlo technique. The MDA values were determined under different conditions according to the counting spectra obtained from the Monte Carlo simulation. The equivalent mass thickness method was applied to the Monte Carlo modeling for monitoring ground radiation to reduce sta- tistical uncertainty. The secondary source method was used to monitor both air and ground radiation. A quadratic relationship was found between the MDA and activity concentration. An exponential relationship was found between the MDA and altitude The MDA of a specific radionuclide from external detectors was found to be superior to that obtained from internal detectors under the same conditions. The MDA values in an NaI(Tl) AGRS system under different conditions can be estimated based on the results of this study. 展开更多
关键词 NaI(TI) airborne γ-ray spectrometry minimum detectable activity Monte Carlo simulation
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Improved Minimum Detectable Velocity in Bistatic Space-Based Radar 被引量:1
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作者 李华 汤俊 彭应宁 《Tsinghua Science and Technology》 SCIE EI CAS 2008年第1期30-34,共5页
Single orbit bistatic space-based radar (SBR) is composed of two radars in the same orbit. The characteristics of the clutter Doppler-angle spectrum of a single orbit bistatic SBR show that the slope of the mainbeam... Single orbit bistatic space-based radar (SBR) is composed of two radars in the same orbit. The characteristics of the clutter Doppler-angle spectrum of a single orbit bistatic SBR show that the slope of the mainbeam clutter spectrum is highly sensitive to the cone angles. Therefore, the minimum detectable velocity of the bistatic system is dependent on the cone angle. Then a new combined working mode of singleorbit bistatic SBR system was developed in which one radar will act as the transmitter and another as the receiver to improve detection performance for all angles. Simulation results by space-time adaptive processing verify the improved detection performance. The new design also reduces the average power of each radar system and the size and weight of the on-board solar array-battery system. 展开更多
关键词 bistatic space based radar minimum detectable velocity CLUTTER space-time adaptive processing
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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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Automated Pipe Defect Identification in Underwater Robot Imagery with Deep Learning 被引量:1
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作者 Mansour Taheri Andani Farhad Ameri 《哈尔滨工程大学学报(英文版)》 2026年第1期197-215,共19页
Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challeng... Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challenge due to factors such as light scattering,absorption,restricted visibility,and ambient noise.The advancement of deep learning has introduced powerful techniques for processing large amounts of unstructured and imperfect data collected from underwater environments.This study evaluated the efficacy of the You Only Look Once(YOLO)algorithm,a real-time object detection and localization model based on convolutional neural networks,in identifying and classifying various types of pipeline defects in underwater settings.YOLOv8,the latest evolution in the YOLO family,integrates advanced capabilities,such as anchor-free detection,a cross-stage partial network backbone for efficient feature extraction,and a feature pyramid network+path aggregation network neck for robust multi-scale object detection,which make it particularly well-suited for complex underwater environments.Due to the lack of suitable open-access datasets for underwater pipeline defects,a custom dataset was captured using a remotely operated vehicle in a controlled environment.This application has the following assets available for use.Extensive experimentation demonstrated that YOLOv8 X-Large consistently outperformed other models in terms of pipe defect detection and classification and achieved a strong balance between precision and recall in identifying pipeline cracks,rust,corners,defective welds,flanges,tapes,and holes.This research establishes the baseline performance of YOLOv8 for underwater defect detection and showcases its potential to enhance the reliability and efficiency of pipeline inspection tasks in challenging underwater environments. 展开更多
关键词 YOLO8 Underwater robot Object detection Underwater pipelines Remotely operated vehicle Deep learning
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Establishment of a quintuple PCR detection method for ginger soil-borne pathogens
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作者 YANG Wei-chao LAN Da-yu +5 位作者 HUANG Hao WEN Jun-li LI Hong-lei CHE Jiang-lü ZHOU Sheng-mao YUAN Gao-qing 《南方农业学报》 北大核心 2026年第2期474-485,共12页
【Objective】This study aimed to establish a quintuple PCR method for rapid and simultaneous detection of Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provided tech... 【Objective】This study aimed to establish a quintuple PCR method for rapid and simultaneous detection of Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provided technical support for early diagnosis of various soil-borne diseases on ginger.【Method】For five types of soil-borne pathogens causing ginger bacterial wilt and rhizome rot,specific primer combinations were designed and screened,the optimal quintuple reaction system was established by exploring optimal primer concentrations,annealing temperature,and sensitivity,and was applied to detect field plant samples to verify its utility.【Result】Specific primers pairs Rs1F/Rs1R,En1F/En1R,and Py1F/Py1R were designed according to flic gene of Ralstonia solanacearum,rpoB gene of Enterobacter spp.,and 18S rDNA of Pythium spp.,and combined with reported Fusarium spp.specific primers Fu3/Fu4 and specific primers 23SPecF/23SPecR of Pectobacterium spp.,a quintuple PCR reaction system for ginger soil-borne pathogens has been established(25.00μL):above primer dosage was 1.20,0.20,0.60,1.60,and 0.15μL respectively;2×PCR Mix 12.50μL;DNA templates of different pathogens were 1.00μL each;added ddH_(2)O to 25.00μL.Annealing temperature was optimized to 55.4℃.The specific fragments with sizes of 516,370,266,207,and 159 bp could be amplified simultaneously in the established quintuple PCR system,and the detection limit of this system for Ralstonia solanacearum,Enterobacter spp.and Pythium spp.reached 10^(-1)pg/μL,for Fusarium spp.and Pectobacterium spp.was 1 pg/μL,and for detecting five pathogens simultaneously was 10^(3)pg/μL.The multiplex PCR system established in this study could successfully detect the diseased plant samples from the field.【Conclusion】The quintuple PCR system established is able to rapid ly and accurately detect Ralstonia solanacearum,Fusarium spp.,Pectobacterium spp.,Enterobacter spp.,and Pythium spp.,which provides a useful tool for timely diagnosis and epidemic monitoring of various soil-borne diseases of ginger. 展开更多
关键词 GINGER soil-borne pathogen quintuple PCR detection system epidemic monitoring
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Dual-Signal Colorimetric/Fluorescent Detection of Vibrio parahaemolyticus in Seafood Using a Multifunctional Aptamer-Conjugated Magnetic Covalent Organic Framework-CuO/Au Nanozyme
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作者 SUN Di YANG Xuewen +6 位作者 WANG Hui LIN Hongyong HE Xiaoxia HUO Zhenting LIU Yu YU Zhongjie JIANG Wei 《食品科学》 北大核心 2026年第6期23-40,共18页
In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detec... In this study,a multifunctional aptamer-conjugated magnetic covalent organic framework(COF)-CuO/Au nanozyme(MCOF-CuO/Au@apt)was developed as a“three-in-one”platform for dual-signal colorimetric and fluorescent detection of Vibrio parahaemolyticus.The nanozyme integrated magnetic separation,peroxidase-like catalytic activity,and specific target recognition through an aptamer-based strategy.Upon binding to V.parahaemolyticus,the catalytic oxidation of tetra-aminophenylethylene(TPE-4A)by the nanozyme was selectively inhibited,resulting in distinct colorimetric and fluorescent signals that significantly enhanced the detection accuracy and reliability.The proposed method exhibited high sensitivity,with limits of detection(LOD)of 21 and 7 CFU/mL for the colorimetric and fluorescent assays,respectively.The performance of this method was validated using real seafood samples,including Penaeus vannamei,Mytilus coruscus,and Crassostrea gigas,which showed high recovery rates(101.11%-107.30%)and excellent reproducibility.The system also demonstrated strong specificity and accuracy under various conditions,confirming its robustness and practical applicability.Collectively,this innovative platform presents a promising solution for the rapid,versatile,and sensitive detection of V.parahaemolyticus in seafood,with considerable potential to advance food safety diagnosis and on-site monitoring. 展开更多
关键词 Vibrio parahaemolyticus dual-signal detection aptamer-based nanozyme magnetic covalent organic framework seafood safety
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Intelligent analysis of direct coal liquefaction diesel components by near-infrared spectroscopy
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作者 WANG Xiwu LI Haowei +4 位作者 QI Zhendong WANG Xingbao FENG Jie ZHU Yimeng LI Wenying 《燃料化学学报(中英文)》 北大核心 2026年第4期17-28,共12页
Diesel accounts for over 60%of the products derived from direct coal liquefaction(DCL).Compared to petroleum-based diesel,DCL diesel exhibits a cetane number ranging from 30 to 40,which fails to meet the automotive di... Diesel accounts for over 60%of the products derived from direct coal liquefaction(DCL).Compared to petroleum-based diesel,DCL diesel exhibits a cetane number ranging from 30 to 40,which fails to meet the automotive diesel standard requirement of≥45.Therefore,rapid and accurate analysis of its chemical composition is crucial for property optimization to meet fuel specifications by component blending.Thought traditional methods like gas chromatography offer high accuracy,they are unsuitable for rapid online analysis under industrial conditions.Near-infrared(NIR)spectroscopy can provide advantages in rapid,non-destructive analysis.Its application however,is limited by the complexity of spectral data interpretation.Machine learning(ML)is effective method for extracting valuable information from spectra and establishing high-precision prediction models.This study integrates NIR spectroscopy with ML to construct a spectral-composition database for DCL diesel.Feature extraction was performed using the correlation coefficient and mutual information methods to screen key wavelength variables and reduce data dimensionality.Subsequently,the predictive performance of three ML models—Lasso,SVR and XGBoost—was compared.Results indicate that excluding spectral data with absorbance greater than 1 significantly enhances model accuracy,increasing the test set R^(2) from 0.85 to 0.96.After feature extraction,the optimal number of wavelength variables was reduced to 177,substantially improving computational efficiency.Among the models evaluated,the SVR-MI-0.9 model,based on mutual information feature selection,demonstrated the best performance,achieving training and test set R^(2) values both exceeding 0.98.This model enables precise prediction of paraffin,naphthene,and aromatic hydrocarbon contents.This research provides a robust methodology for intelligent online quality monitoring.An intelligent NIR spectroscopy data analysis software was independently developed based on the established model.Compared with comprehensive two-dimensional gas chromatography,the software reduced the analysis time by over 98%,with an absolute prediction error below 0.2%.Thus,rapid analysis of DCL diesel components was successfully realized. 展开更多
关键词 direct coal liquefaction diesel real-time spectral detection machine learning feature extraction component prediction
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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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A Dual-Detection Method for Cashew Ripeness and Anthrax Based on YOLOv11-NSDDil
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作者 Ran Liu Yawen Chen +1 位作者 Dong Yang Jingjing Yang 《Computers, Materials & Continua》 2026年第2期1919-1941,共23页
In the field of smart agriculture,accurate and efficient object detection technology is crucial for automated crop management.A particularly challenging task in this domain is small object detection,such as the identi... In the field of smart agriculture,accurate and efficient object detection technology is crucial for automated crop management.A particularly challenging task in this domain is small object detection,such as the identification of immature fruits or early stage disease spots.These objects pose significant difficulties due to their small pixel coverage,limited feature information,substantial scale variations,and high susceptibility to complex background interference.These challenges frequently result in inadequate accuracy and robustness in current detection models.This study addresses two critical needs in the cashew cultivation industry—fruitmaturity and anthracnose detection—by proposing an improved YOLOv11-NSDDil model.The method introduces three key technological innovations:(1)The SDDil module is designed and integrated into the backbone network.This module combines depthwise separable convolution with the SimAM attention mechanism to expand the receptive field and enhance contextual semantic capture at a low computational cost,effectively alleviating the feature deficiency problem caused by limited pixel coverage of small objects.Simultaneously,the SDmodule dynamically enhances discriminative features and suppresses background noise,significantly improving the model’s feature discrimination capability in complex environments;(2)The introduction of the DynamicScalSeq-Zoom_cat neck network,significantly improving multi-scale feature fusion;and(3)The optimization of the Minimum Point Distance Intersection over Union(MPDIoU)loss function,which enhances bounding box localization accuracy byminimizing vertex distance.Experimental results on a self-constructed cashew dataset containing 1123 images demonstrate significant performance improvements in the enhanced model:mAP50 reaches 0.825,a 4.6% increase compared to the originalYOLOv11;mAP50-95 improves to 0.624,a 6.5% increase;and recall rises to 0.777,a 2.4%increase.This provides a reliable technical solution for intelligent quality inspection of agricultural products and holds broad application prospects. 展开更多
关键词 Deep learning object detection multi-scale fusion small object detection miss detection false detection
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Motion Planning of an Autonomous Underwater Vehicle via the Integrated Design of Detection,Communication and Control
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作者 Tianyi Guo Jing Yan +2 位作者 Xian Yang Tianyi Zhang Xinping Guan 《IEEE/CAA Journal of Automatica Sinica》 2026年第1期218-220,共3页
Dear Editor,This letter studies the motion planning issue for an autonomous underwater vehicle(AUV)in obstacle environment.We propose a novel integrated detection-communication waveform that enables simultaneous obsta... Dear Editor,This letter studies the motion planning issue for an autonomous underwater vehicle(AUV)in obstacle environment.We propose a novel integrated detection-communication waveform that enables simultaneous obstacle detection and self-localization. 展开更多
关键词 communication waveform motion planning obstacle detection autonomous underwater vehicle integrated detection simultaneous obstacle detection autonomous underwater vehicle auv obstacle environment
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ZeroDefense:An adaptive hybrid fusion-based intrusion detection system for zero-day threat detection in IoT networks
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作者 Abubakar Wakili Sara Bakkali 《Journal of Electronic Science and Technology》 2026年第1期29-45,共17页
Zero-day attacks present a critical cybersecurity challenge for Internet of things(IoT)infrastructures,where the inability of signature-based intrusion detection systems(IDSs)to recognize novel threat behaviors compro... Zero-day attacks present a critical cybersecurity challenge for Internet of things(IoT)infrastructures,where the inability of signature-based intrusion detection systems(IDSs)to recognize novel threat behaviors compromises both system reliability and operational continuity.Existing hybrid IDS solutions often struggle to balance accurate classification of known attacks with reliable anomaly detection,particularly under the computational constraints of IoT environments.To address this gap,we introduce ZeroDefense,an adaptive fusion-based IDS designed for simultaneous detection of known intrusions and emerging zero-day threats.The framework employs a four-layer architecture consisting of i)feature standardization and class balancing,ii)anomaly detection using isolation forest,autoencoder,and local outlier factor,iii)fine-grained attack classification via random forest,extreme gradient boosting(XGBoost),light gradient boosting machine(LightGBM),and attentive interpretable tabular learning(TabNet),and iv)a confidence-aware fusion engine that adaptively selects the most reliable decision path.Suspicious or previously unseen traffic is isolated early through fused anomaly scoring,while benign and known-malicious flows are processed through supervised classification for precise attack labeling.With an anomaly cascaded decision pipeline,a dynamic confidence-driven fusion mechanism,and a deploymentconscious design,ZeroDefense enables real-time inference on IoT edge gateways.Evaluation on the CICIoT2023 benchmark demonstrates 99.94% overall accuracy and 95.64%macro-average F1-score for known attacks,while 5.76% of traffic is successfully flagged as potential zero-day activity,with inference latency maintained below 100 ms/flow.These results indicate that ZeroDefense offers a scalable,resilient,and practically deployable defense capability for modern IoT infrastructures. 展开更多
关键词 Anomaly detection Hybrid fusion Internet of things(IoT) Intrusion detection system IoT security Resilient digital infrastructure Zero-day detection
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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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CLF-YOLOv8:Lightweight Multi-Scale Fusion with Focal Geometric Loss for Real-Time Night Maritime Detection
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作者 Zhonghao Wang Xin Liu +1 位作者 Changhua Yue Haiwen Yuan 《Computers, Materials & Continua》 2026年第2期1667-1689,共23页
To address critical challenges in nighttime ship detection—high small-target missed detection(over 20%),insufficient lightweighting,and limited generalization due to scarce,low-quality datasets—this study proposes a... To address critical challenges in nighttime ship detection—high small-target missed detection(over 20%),insufficient lightweighting,and limited generalization due to scarce,low-quality datasets—this study proposes a systematic solution.First,a high-quality Night-Ships dataset is constructed via CycleGAN-based day-night transfer,combined with a dual-threshold cleaning strategy(Laplacian variance sharpness filtering and brightness-color deviation screening).Second,a Cross-stage Lightweight Fusion-You Only Look Once version 8(CLF-YOLOv8)is proposed with key improvements:the Neck network is reconstructed by replacing Cross Stage Partial(CSP)structure with the Cross Stage Partial Multi-Scale Convolutional Block(CSP-MSCB)and integrating Bidirectional Feature Pyramid Network(BiFPN)for weighted multi-scale fusion to enhance small-target detection;a Lightweight Shared Convolutional and Separated Batch Normalization Detection-Head(LSCSBD-Head)with shared convolutions and layer-wise Batch Normalization(BN)reduces parameters to 1.8M(42% fewer than YOLOv8n);and the FocalMinimum Point Distance Intersection over Union(Focal-MPDIoU)loss combines Minimum Point Distance Intersection over Union(MPDIoU)geometric constraints and Focal weighting to optimize low-overlap targets.Experiments show CLFYOLOv8 achieves 97.6%mAP@0.5(0.7% higher than YOLOv8n)with 1.8 M parameters,outperforming mainstream models in small-target detection,overlapping target discrimination,and adaptability to complex lighting. 展开更多
关键词 Nighttime ship detection lightweight model small object detection BiFPN LSCSBD-Head Focal-MPDIoU YOLOv8
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A Comprehensive Literature Review on YOLO-Based Small Object Detection:Methods,Challenges,and Future Trends
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作者 Hui Yu Jun Liu Mingwei Lin 《Computers, Materials & Continua》 2026年第4期258-309,共52页
Small object detection has been a focus of attention since the emergence of deep learning-based object detection.Although classical object detection frameworks have made significant contributions to the development of... Small object detection has been a focus of attention since the emergence of deep learning-based object detection.Although classical object detection frameworks have made significant contributions to the development of object detection,there are still many issues to be resolved in detecting small objects due to the inherent complexity and diversity of real-world visual scenes.In particular,the YOLO(You Only Look Once)series of detection models,renowned for their real-time performance,have undergone numerous adaptations aimed at improving the detection of small targets.In this survey,we summarize the state-of-the-art YOLO-based small object detection methods.This review presents a systematic categorization of YOLO-based approaches for small-object detection,organized into four methodological avenues,namely attention-based feature enhancement,detection-head optimization,loss function,and multi-scale feature fusion strategies.We then examine the principal challenges addressed by each category.Finally,we analyze the performance of thesemethods on public benchmarks and,by comparing current approaches,identify limitations and outline directions for future research. 展开更多
关键词 Small object detection YOLO real-time detection feature fusion deep learning
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