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Te-Modulated Fe Single Atom with Synergistic Bidirectional Catalysis for High-Rate and Long-Cycling Lithium-Sulfur Battery
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作者 Jian Guo Lu Chen +4 位作者 Lijun Wang Kangfei Liu Ting He Jia Yu Hongbin Zhao 《Nano-Micro Letters》 2026年第1期827-842,共16页
Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development... Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development of highly efficient SACs and a comprehensive understanding of their structure-activity relationships remain enormously challenging.Herein,a novel kind of Fe-based SAC featuring an asymmetric FeN_(5)-TeN_(4) coordination structure was precisely designed by introducing Te atom adjacent to the Fe active center to enhance the catalytic activity.Theoretical calculations reveal that the neighboring Te atom modulates the local coordination environment of the central Fe site,elevating the d-band center closer to the Fermi level and strengthening the d-p orbital hybridization between the catalyst and sulfur species,thereby immobilizing polysulfides and improving the bidirectional catalysis of Li-S redox.Consequently,the Fe-Te atom pair catalyst endows Li-S batteries with exceptional rate performance,achieving a high specific capacity of 735 mAh g^(−1) at 5 C,and remarkable cycling stability with a low decay rate of 0.038%per cycle over 1000 cycles at 1 C.This work provides fundamental insights into the electronic structure modulation of SACs and establishes a clear correlation between precisely engineered atomic configurations and their enhanced catalytic performance in Li-S electrochemistry. 展开更多
关键词 Single-atom catalyst Coordination environment Electronic structure bidirectional catalysis Li-S batteries
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Intelligent Human Interaction Recognition with Multi-Modal Feature Extraction and Bidirectional LSTM
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作者 Muhammad Hamdan Azhar Yanfeng Wu +4 位作者 Nouf Abdullah Almujally Shuaa S.Alharbi Asaad Algarni Ahmad Jalal Hui Liu 《Computers, Materials & Continua》 2026年第4期1632-1649,共18页
Recognizing human interactions in RGB videos is a critical task in computer vision,with applications in video surveillance.Existing deep learning-based architectures have achieved strong results,but are computationall... Recognizing human interactions in RGB videos is a critical task in computer vision,with applications in video surveillance.Existing deep learning-based architectures have achieved strong results,but are computationally intensive,sensitive to video resolution changes and often fail in crowded scenes.We propose a novel hybrid system that is computationally efficient,robust to degraded video quality and able to filter out irrelevant individuals,making it suitable for real-life use.The system leverages multi-modal handcrafted features for interaction representation and a deep learning classifier for capturing complex dependencies.Using Mask R-CNN and YOLO11-Pose,we extract grayscale silhouettes and keypoint coordinates of interacting individuals,while filtering out irrelevant individuals using a proposed algorithm.From these,we extract silhouette-based features(local ternary pattern and histogram of optical flow)and keypoint-based features(distances,angles and velocities)that capture distinct spatial and temporal information.A Bidirectional Long Short-Term Memory network(BiLSTM)then classifies the interactions.Extensive experiments on the UT Interaction,SBU Kinect Interaction and the ISR-UOL 3D social activity datasets demonstrate that our system achieves competitive accuracy.They also validate the effectiveness of the chosen features and classifier,along with the proposed system’s computational efficiency and robustness to occlusion. 展开更多
关键词 Human interaction recognition keypoint coordinates grayscale silhouettes bidirectional long shortterm memory network
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An Ultrasonic Microrobot Enabling Ultrafast Bidirectional Navigation in Confinned Tubular Environments
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作者 Meng Cui Liyun Zhen +5 位作者 Xingyu Bai Lihan Yu Xuhao Chen Jingquan Liu Qingkun Liu Bin Yang 《Nano-Micro Letters》 2026年第2期183-198,共16页
Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined sp... Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes. 展开更多
关键词 Ultrasonic microrobot Piezoelectric composite film microstructure MEMS fabrication bidirectional locomotion Confined pipeline inspection
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PI3K/Akt/mTOR-mediated bidirectional regulation of ampelopsin from Nekemias megalophylla modulates autophagy and apoptosis in cervical cancer
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作者 Shiyi Xu Siyu Liao +6 位作者 Juan Xi Ling Gong Xue Zou Xiaoli Yang Jiangxue Di Xiuqiao Zhang Chun Gui 《Food Science and Human Wellness》 2026年第2期804-822,共19页
Nekemias megalophylla is a popular folk tea consumed by people in the Western Hubei(China)of which ampelopsin(AMP)is the main active ingredient.In this study,we investigated the effect of AMP on cervical cancer and ex... Nekemias megalophylla is a popular folk tea consumed by people in the Western Hubei(China)of which ampelopsin(AMP)is the main active ingredient.In this study,we investigated the effect of AMP on cervical cancer and explored its mechanism of action,focusing on apoptosis and autophagy.Firstly,we verified that AMP strongly inhibited the growth of C-33A cells and observed apoptosis and autophagy phenomenon in vivo,and found that AMP induces C-33A cell apoptosis via death receptor or mitochondrial pathways.The results also indicated that AMP-induced autophagy occurs via the PI3K/Akt/m TOR pathway.Secondly,when autophagy was inhibited,the AMP-induced apoptosis of C-33A cells was strengthened,when apoptosis was inhibited,the AMP-induced autophagy of C-33A cells was strengthened.PI3K/Akt/m TOR pathway activation enhances AMP-induced apoptosis in C-33A cells,while its inhibition strengthens AMP-induced autophagy.Finally,we confirmed that AMP inhibited cell growth and induced apoptosis and autophagy of C-33A cells in an in vivo nude mouse model of C-33A tumor xenografts.These results elucidate that AMP bidirectionally regulates apoptosis and autophagy in human cervical cancer C-33A cells by mediating the PI3K/Akt/m TOR pathway. 展开更多
关键词 AMPELOPSIN APOPTOSIS AUTOPHAGY C-33A cell PI3K/AKT/MTOR bidirectional regulation
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基于双目视觉的BRDF绝对测量装置位姿标校技术 被引量:3
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作者 郑修文 陈洪耀 +2 位作者 李鑫 张黎明 杨宝云 《光子学报》 北大核心 2025年第8期149-163,共15页
在双向反射分布函数(BRDF)绝对测量系统中,采用串联式机械臂作为转角机构时,其末端工具坐标系的位姿误差是系统不确定度的重要来源之一。为降低机械臂位姿误差对BRDF绝对测量系统转角精度的影响,使用双目相机作为机械臂位姿测量工具,并... 在双向反射分布函数(BRDF)绝对测量系统中,采用串联式机械臂作为转角机构时,其末端工具坐标系的位姿误差是系统不确定度的重要来源之一。为降低机械臂位姿误差对BRDF绝对测量系统转角精度的影响,使用双目相机作为机械臂位姿测量工具,并根据BRDF测量装置定点多姿态的运动方式,提出一种相对BRDF测量原点的机械臂位姿校正方法。对光路入/反射天顶角角度为0~60°,方位角为0~360°时机械臂的姿态误差进行测量,采用多层感知器人工神经网络模型(MLP)对机械臂姿态误差进行训练,最后建立机械臂转角位姿误差补偿模型。在MLP模型的预测和补偿下,位置平均误差从0.626 mm降低到0.162 mm,角度平均误差从0.289°降低到0.059°。定量评估了机械臂位姿补偿不确定度,位置和姿态的补偿不确定度分别为0.07 mm和0.034°。同时分析机械臂的转角误差与BRDF测量角度误差之间的关系,结果表明由机械臂自身转角误差造成的BRDF测量角度误差与机械臂转角误差处于同一量级。 展开更多
关键词 双向反射分布函数 测量装置 串联式机械臂标定 转角变换 双目视觉测量 多层感知器人工神经网络
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生成式数据驱动BRDF参考数据库建立方法
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作者 刘彦磊 袁大庆 +3 位作者 熊行创 李舒鹏 周孝好 刘子龙 《计量学报》 北大核心 2025年第5期651-658,共8页
以测量数据为基础,结合微面元理论提出了一种双向反射分布函数(BRDF)参考数据库建立方法,并开发了相应的系统,包括数据读取、法线密度分布函数、遮挡因子、模型结构。首先,采用模拟退火算法以角度信息量I模拟为目标函数,研究了不同采样... 以测量数据为基础,结合微面元理论提出了一种双向反射分布函数(BRDF)参考数据库建立方法,并开发了相应的系统,包括数据读取、法线密度分布函数、遮挡因子、模型结构。首先,采用模拟退火算法以角度信息量I模拟为目标函数,研究了不同采样角度个数对拟合和反演效果的影响;其次,采用将BRDF模型拆解并模块化的方式建立了能够描述目标表面信息的模块,通过各个模块的组合建立BRDF模型库;最后,以少量的测量数据为基础,通过模型的选择、参数的设定、反演效果的评定等环节生成可靠的BRDF数据。该方法一方面能够减弱对海量测量数据的依赖,另一方面以少量的测量数据为“框架”有效避免了多模型的不一致性。以锌的半球空间BRDF为实例对测量和反演结果进行了对比,验证了该方法的可靠性。 展开更多
关键词 光学计量 双向反射分布函数 采样方式 模型库 参考数据库 微面元理论
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基于多角度实测的湖冰BRDF特性研究
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作者 肖扬 李略 +3 位作者 杨倩 刘焕军 郝晓华 林楠 《冰川冻土》 2025年第1期282-293,共12页
双向反射分布函数(Bidirectional Reflectance Distribution Function,BRDF)描述地表反射的各向异性分布特征,是定量遥感研究的重要参数。本研究利用ASD Field Spec 4便携式地物光谱仪和多角度观测支架采集查干湖冰封期不同类型积雪和湖... 双向反射分布函数(Bidirectional Reflectance Distribution Function,BRDF)描述地表反射的各向异性分布特征,是定量遥感研究的重要参数。本研究利用ASD Field Spec 4便携式地物光谱仪和多角度观测支架采集查干湖冰封期不同类型积雪和湖冰BRDF,并利用Savitzky-Golay滤波法处理光谱数据,基于地面观测数据分析黑冰、白冰、灰冰、蓝冰和雪的BRDF反射特性,同时探索气泡及杂质对冰雪BRDF反射光谱特性的影响。结果显示,湖冰和积雪表面反射率随天顶角的增加而增加,当方位角为0°和45°时,呈现出明显的各向异性。不同种类的湖冰光谱反射率具有共同的变化特征:当波长位于350~600 nm,湖冰反射率随波长的增大而增大,在600 nm附近反射率达到峰值;当波长位于600~1300 nm,反射率随波长增大而减小,直至完全被吸收。对比不同气泡大小的黑冰光谱特性发现,气泡主要影响350~1000 nm范围内的反射率,气泡的存在增加了黑冰反射率。本研究旨在为湖冰遥感反演算法提供实测数据和机理研究。 展开更多
关键词 湖冰 积雪 双向反射分布函数 地面观测 反射光谱特性
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变温条件下的红外偏振BRDF快速测量系统
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作者 黄昂 王景辉 +4 位作者 董伟 孟凡山 黄帅 李益文 冯国进 《光谱学与光谱分析》 北大核心 2025年第3期650-657,共8页
在变温条件下的红外偏振BRDF能准确反映材料表面的辐射特性,为表面光学特性研究提供基础数据,在热成像和红外目标检测等领域有广泛的应用前景。然而,目前的偏振BRDF测量系统主要采用离散逐点扫描方式,单角度扫描时间在5 min以上,完整BRD... 在变温条件下的红外偏振BRDF能准确反映材料表面的辐射特性,为表面光学特性研究提供基础数据,在热成像和红外目标检测等领域有广泛的应用前景。然而,目前的偏振BRDF测量系统主要采用离散逐点扫描方式,单角度扫描时间在5 min以上,完整BRDF测量时间达数小时,并且分辨率较低。在应用于变温测量时,需要长时间保持样品表面的高温,这会导致能耗增加且实施困难。因此,迫切需要研究快速测量方法。研制一套可实现室温~1000℃便携式样片加热的红外偏振BRDF测量系统,克服机械臂的负载和耐温问题。针对研制系统构建测量模型,并提出一种基于机械臂的偏振BRDF连续扫描方法,通过机械臂离散转动-环轨连续扫描和环轨离散转动-机械臂连续扫描两种方式实现不同偏振态下的三维BRDF快速连续测量,在提高测量速度的同时提高了测量分辨率,单角度扫描时间在1 min以内,完整BRDF测量时间缩短至约1 h,更适用于变温BRDF测量。将所提出的测量方法应用于镜面反射较强的磨砂不锈钢样片表面变温BRDF测量,针对强反射位置附近进行精细连续扫描,获得6.1×10^(-6)、1.37×10^(-5)和3.81×10^(-5) sr三种探测立体角度下的局部偏振BRDF三维分布。立体角越大,空间滤波效果越强,显现出更小的测量峰值,这与BRDF理论测量模型相吻合。因此,在进行强镜面反射材料的BRDF测量时,需要采用小立体角探测,减小空间滤波效应,不锈钢样片测量采用6.1×10^(-6) sr的立体角。在变温实验中,当温度升高时,不锈钢样片表面发生氧化反应,S和P偏振BRDF峰值均随温度升高而降低,两个偏振态下的最大测量标准差相比于BRDF平均值占比分别为0.56%和0.24%,不同温度下BRDF测量重复性较好,且两者变化趋于一致,说明了研制系统的偏振BRDF测量的有效性。 展开更多
关键词 双向反射分布函数 偏振测量 变温环境 红外反射
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Effect of etomidate added to propofol target-controlled infusion in bidirectional endoscopy:A randomized clinical trial 被引量:2
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作者 Hui-Rong Luo An-Di Chen +6 位作者 Jing-Fang Lin Peng Ye Ying-Jie Chen Ming-Xue Lin Pin-Zhong Chen Xiao-Hui Chen Xiao-Chun Zheng 《World Journal of Gastrointestinal Endoscopy》 2025年第2期55-64,共10页
BACKGROUND Propofol has been widely used in bidirectional gastrointestinal endoscopy sedation;however,it frequently leads to cardiovascular adverse events and respiratory depression.Propofol target-controlled infusion... BACKGROUND Propofol has been widely used in bidirectional gastrointestinal endoscopy sedation;however,it frequently leads to cardiovascular adverse events and respiratory depression.Propofol target-controlled infusion(TCI)can provide safe sedation but may require higher dosages of propofol.On the contrary,etomidate offers hemodynamic stability.AIM To evaluate the effect of different dose etomidate added to propofol TCI sedation during same-visit bidirectional endoscopy.METHODS A total of 330 patients from Fujian Provincial Hospital were randomly divided into three groups:P,0.1EP,and 0.15EP.Patients in the P group received propofol TCI only,with an initial effect-site concentration of the propofol TCI system of 3.0 mg/mL.Patients in the 0.1EP and 0.15EP groups received 0.1 and 0.15 mg/kg etomidate intravenous injection,respectively,followed by propofol TCI.RESULTS Patients in the 0.15EP group had higher mean blood pressure after induction than the other groups(P group:78 mmHg,0.1EP group:82 mmHg,0.15EP group:88 mmHg;P<0.05).Total doses of propofol consumption significantly decreased in the 0.15EP group compared with that in the other groups(P group:260.6 mg,0.1EP group:228.1 mg,0.15EP group:201.2 mg;P<0.05).The induction time was longer in the P group than in the other groups(P group:1.9±0.7 minutes,0.1EP group:1.2±0.4 minutes,0.15EP group:1.1±0.3 minutes;P<0.01).The recovery time was shorter in the 0.15EP group than in the other groups(P group:4.8±2.1 minutes,0.1EP group:4.5±1.6 minutes,0.15EP group:3.9±1.4 minutes;P<0.01).The incidence of hypotension(P group:36.4%,0.1EP group:29.1%,0.15EP group:11.8%;P<0.01)and injection pain was lower in the 0.15EP group than in the other groups(P<0.05).Furthermore,the incidence of respiratory depression was lower in the 0.15EP group than in the P group(P<0.05).Additionally,the satisfaction of the patient,endoscopist,and anesthesiologist was higher in the 0.15EP group than in the other groups(P<0.05).CONCLUSION Our findings suggest that 0.15 mg/kg etomidate plus propofol TCI can significantly reduce propofol consumption,which is followed by fewer cardiovascular adverse events and respiratory depression,along with higher patient,endoscopist,and anesthesiologist satisfaction. 展开更多
关键词 PROPOFOL ETOMIDATE Target-controlled infusion bidirectional endoscopy Adverse reactions
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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni_(2)P for lithium-sulfur batteries 被引量:2
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作者 Lin Peng Yu Bai +3 位作者 Hang Li Meixiu Qu Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第1期760-769,共10页
Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish ... Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox dynamics.Herein,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur conversion.The study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur species.Meanwhile,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation processes.Thus,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion. 展开更多
关键词 B-doped atoms P vacancies Nickel phosphide bidirectional sulfur conversion Lithium-sulfur batteries
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基于BRDF的多角度光谱曲线反演模型
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作者 刘振 孙旭 +3 位作者 沙建军 孙赫 王德港 高连如 《中国空间科学技术(中英文)》 北大核心 2025年第4期37-47,共11页
为了解决先验光谱库与实测高光谱图像采集倾角不同导致匹配探测精度较低的问题,提出了一种基于核驱动双向反射分布函数BRDF的倾斜光谱曲线反演模型。首先将光谱曲线按照波段拆分,再依据BRDF方程拟合各波段反射率与探测倾角的变化关系,... 为了解决先验光谱库与实测高光谱图像采集倾角不同导致匹配探测精度较低的问题,提出了一种基于核驱动双向反射分布函数BRDF的倾斜光谱曲线反演模型。首先将光谱曲线按照波段拆分,再依据BRDF方程拟合各波段反射率与探测倾角的变化关系,建立反射率反演模型。针对特定倾角采集的高光谱图像,采用反演算法反演出相应倾角下的先验光谱,并进行匹配探测。实验中,使用自主设计组装的野外多角度光谱测量系统,采集了荒漠伪装网及其背景干枯草地的多角度光谱数据,并对其光谱特征进行了分析,同时对比了多种反演算法的性能。实验结果表明,不同地物的反射率分别以相似的趋势随探测倾角变化,拟合光谱曲线与实测光谱曲线差异较小,两者的决定系数均超过0.83,光谱夹角均小于1°。与不同倾角采集的先验光谱相比,反演模型生成的与图像采集角度一致的先验光谱在匹配探测中的AUC值有所提高。本研究丰富了多角度遥感的相关研究,并有效地将多角度遥感应用于高光谱目标探测领域。通过建立的反演模型,提高了高光谱图像匹配探测的精度,具有理论和实际意义。 展开更多
关键词 多角度遥感 双向反射分布函数 光谱曲线反演 倾斜测量 高光谱目标探测
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Analysis of scattering characteristics of coating materials through coupling of BRDF spectral polarization imaging with Torrance-Sparrow model
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作者 CHEN Feng CHEN Guibo +3 位作者 ZHANG Ye WANG Jianbo LIU Yanli XUE Fang 《Optoelectronics Letters》 2025年第5期271-277,共7页
To identify coatings and analyze the anti-detection capabilities of camouflage patterns, material samples can be prepared using the super-pixel segmentation method. A spectral polarization imaging system is developed,... To identify coatings and analyze the anti-detection capabilities of camouflage patterns, material samples can be prepared using the super-pixel segmentation method. A spectral polarization imaging system is developed, based on the principle of bidirectional reflectance distribution function(BRDF), to obtain spectral reflection intensities of coatings at full spatial angles, and use polarization images to calculate the refractive index by the Fresnel equation. The index is then coupled into TorranceSparrow model to simulate the spectral scattering intensity to mutually verify the experimental results. The spectral scattering characteristics of standard camouflage patterns are then revealed and pinpoint the signature band and the angle of reflecting sensitivity. 展开更多
关键词 coating materials brdf spectral polarization imaging fresnel equation polarization images torrancesparrow mod spectral polarization imaging system calculate refractive index bidirectional reflectance distribution function brdf
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基于多角度遥感的湖泊BRDF仿真模型研究
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作者 韩泽莹 乔体洲 +2 位作者 尹中义 胡铂奇 郑佳怡 《科技创新与应用》 2025年第9期37-40,45,共5页
BRDF是湖泊水体光学特性研究与辐射传输仿真研究的重要模型,该文通过对常用海洋方向辐射仿真模型在内陆湖泊的应用,对中国太湖这一典型浑浊内陆湖泊进行适用性分析。根据太湖自然地理特征,将太湖划分为7个湖湾区域。根据5个半经验BRDF模... BRDF是湖泊水体光学特性研究与辐射传输仿真研究的重要模型,该文通过对常用海洋方向辐射仿真模型在内陆湖泊的应用,对中国太湖这一典型浑浊内陆湖泊进行适用性分析。根据太湖自然地理特征,将太湖划分为7个湖湾区域。根据5个半经验BRDF模型(MAG2002、Lee2004、Park-Ruddick2005、Woerd-Pasterkamp2008和Lee2011)计算方向辐射仿真结果,与多角度MISR卫星遥感数据大气校正后的方向辐射进行定量拟合比较。综合结果表明,Woerd-Pasterkamp2008和Lee2011具有最好的拟合效果,是内陆湖泊适用性最好的模型。 展开更多
关键词 多角度遥感 湖泊 brdf 辐射传输 仿真
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Effects of bidirectional interaction on inelastic seismic response:When is its effect significant?
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作者 Atanu Santra Rana Roy 《Earthquake Engineering and Engineering Vibration》 2025年第1期113-134,共22页
Motivated by the early works on bidirectional interaction and the breakthrough to estimate seismic response to bidirectional shaking via unidirectional analysis,it is essential to answer the question:When is the inter... Motivated by the early works on bidirectional interaction and the breakthrough to estimate seismic response to bidirectional shaking via unidirectional analysis,it is essential to answer the question:When is the interaction effect significant?Early works concluded that the effect of interaction is pronounced for stiff systems;consequently,the straightforward method for estimating seismic response to bidirectional excitation by using unidirectional analyses is verified primarily for short period systems.Hence,it is essential to identify the domain of significance for bidirectional interaction before adopting this simple methodology in design.Several parametrically defined systems with elastoplastic and degrading hysteresis models are studied under near-fault motions,assuming strength-independent and strength-dependent stiffness.The force-based and displacement-based analyses,conducted in parallel,reveal that the interaction effect is considerable for stiff systems,especially with degrading characteristics in a relatively low inelasticity range.However,the bidirectional effect may be significant even for highly flexible systems,especially for residual deformation,which in earlier works was shrouded.The range of significance depends on the hysteresis model,system parameters,and response indices.Regression analysis is carried out with the results of the case studies,and the derived regression models may be used for a preliminary assessment of the impact of interaction in advance. 展开更多
关键词 bidirectional RESIDUAL forward-directive fling force-based displacement-based regression
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Dual-Channel Attention Deep Bidirectional Long Short Term Memory for Enhanced Malware Detection and Risk Mitigation
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作者 Madini O.Alassafi Syed Hamid Hasan 《Computer Modeling in Engineering & Sciences》 2025年第8期2627-2645,共19页
Over the past few years,Malware attacks have become more and more widespread,posing threats to digital assets throughout the world.Although numerous methods have been developed to detect malicious attacks,these malwar... Over the past few years,Malware attacks have become more and more widespread,posing threats to digital assets throughout the world.Although numerous methods have been developed to detect malicious attacks,these malware detection techniques need to be more efficient in detecting new and progressively sophisticated variants of malware.Therefore,the development of more advanced and accurate techniques is necessary for malware detection.This paper introduces a comprehensive Dual-Channel Attention Deep Bidirectional Long Short-Term Memory(DCADBiLSTM)model for malware detection and riskmitigation.The Dual Channel Attention(DCA)mechanism improves themodel’s capability to concentrate on the features that aremost appropriate in the input data,which reduces the false favourable rates.The Bidirectional Long,Short-Term Memory framework helps capture crucial interdependence from past and future circumstances,which is essential for enhancing the model’s understanding of malware behaviour.As soon as malware is detected,the risk mitigation phase is implemented,which evaluates the severity of each threat and helps mitigate threats earlier.The outcomes of the method demonstrate better accuracy of 98.96%,which outperforms traditional models.It indicates the method detects and mitigates several kinds of malware threats,thereby providing a proactive defence mechanism against the emerging challenges in cybersecurity. 展开更多
关键词 CYBERSECURITY risk mitigation malware detection bidirectional long short-termmemory dual-channel attention
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Bidirectional relationship between depression and the risk and prognosis of gastric cancer
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作者 Zhe Chen Ting-Jie Gong Lu Zhao 《World Journal of Gastrointestinal Oncology》 2025年第12期38-44,共7页
Gastric cancer(GC)is a highly prevalent and life-threatening malignant tumor worldwide,posing a serious threat to human health.Depression is also highly prevalent among patients with GC.A complex bidirectional relatio... Gastric cancer(GC)is a highly prevalent and life-threatening malignant tumor worldwide,posing a serious threat to human health.Depression is also highly prevalent among patients with GC.A complex bidirectional relationship exists between the two.A total of 52 articles were included in this study to synthesize the evidence on the association between depression and the risk of GC as well as the prognosis of affected patients.The findings indicated that depression can activate the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis,promote the release of catecholamine neurotransmitters,and influence the proliferation,invasion,and metastasis of GC through signaling pathways such as theβ2-adrenergic receptor.Furthermore,the severity of depression is positively correlated with indicators of GC progression.At the same time,GC can induce or aggravate depression through psychological and cognitive factors,social environment interactions,and diverse pathophysiological mechanisms,including tumor biological characteristics,treatment-related damage,and metabolic disorders.These interactions form a vicious cycle.This minireview summarizes the existing evidence and provides a theoretical basis for clinical interventions aimed at improving treatment outcomes and quality of life in patients with GC. 展开更多
关键词 Gastric cancer DEPRESSION bidirectional relationship Psychological factors Quality of life
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Dynamic Interaction-Aware Trajectory Prediction with Bidirectional Graph Attention Network
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作者 Jun Li Kai Xu +4 位作者 Baozhu Chen Xiaohan Yang Mengting Sun Guojun Li HaoJie Du 《Computers, Materials & Continua》 2025年第11期3349-3368,共20页
Pedestrian trajectory prediction is pivotal and challenging in applications such as autonomous driving,social robotics,and intelligent surveillance systems.Pedestrian trajectory is governed not only by individual inte... Pedestrian trajectory prediction is pivotal and challenging in applications such as autonomous driving,social robotics,and intelligent surveillance systems.Pedestrian trajectory is governed not only by individual intent but also by interactions with surrounding agents.These interactions are critical to trajectory prediction accuracy.While prior studies have employed Convolutional Neural Networks(CNNs)and Graph Convolutional Networks(GCNs)to model such interactions,these methods fail to distinguish varying influence levels among neighboring pedestrians.To address this,we propose a novel model based on a bidirectional graph attention network and spatio-temporal graphs to capture dynamic interactions.Specifically,we construct temporal and spatial graphs encoding the sequential evolution and spatial proximity among pedestrians.These features are then fused and processed by the Bidirectional Graph Attention Network(Bi-GAT),which models the bidirectional interactions between the target pedestrian and its neighbors.The model computes node attention weights(i.e.,similarity scores)to differentially aggregate neighbor information,enabling fine-grained interaction representations.Extensive experiments conducted on two widely used pedestrian trajectory prediction benchmark datasets demonstrate that our approach outperforms existing state-of-theartmethods regarding Average Displacement Error(ADE)and Final Displacement Error(FDE),highlighting its strong prediction accuracy and generalization capability. 展开更多
关键词 Pedestrian trajectory prediction spatio-temporal modeling bidirectional graph attention network autonomous system
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The Joint Model of Multi-Intent Detection and Slot Filling Based on Bidirectional Interaction Structure
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作者 WANG Changjing ZENG Xianghui +2 位作者 WANG Yuxin SUN Yuxin ZUO Zhengkang 《Wuhan University Journal of Natural Sciences》 2025年第1期21-31,共11页
Intent detection and slot filling are two important components of natural language understanding.Because their relevance,joint training is often performed to improve performance.Existing studies mostly use a joint mod... Intent detection and slot filling are two important components of natural language understanding.Because their relevance,joint training is often performed to improve performance.Existing studies mostly use a joint model of multi-intent detection and slot-filling with unidirectional interaction,which improves the overall performance of the model by fusing the intent information in the slot-filling part.On this basis,in order to further improve the overall performance of the model by exploiting the correlation between the two,this paper proposes a joint multi-intent detection and slot-filling model based on a bidirectional interaction structure,which fuses the intent encoding information in the encoding part of slot filling and fuses the slot decoding information in the decoding part of intent detection.Experimental results on two public multi-intent joint training datasets,MixATIS and MixSNIPS,show that the bidirectional interaction structure proposed in this paper can effectively improve the performance of the joint model.In addition,in order to verify the generalization of the bidirectional interaction structure between intent and slot,a joint model for single-intent scenarios is proposed on the basis of the model in this paper.This model also achieves excellent performance on two public single-intent joint training datasets,CAIS and SNIPS. 展开更多
关键词 natural language understanding multi-intent detection slot filling bidirectional interaction joint training
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Bone-organ axes: bidirectional crosstalk
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作者 An-Fu Deng Fu-Xiao Wang +3 位作者 Si-Cheng Wang Ying-Ze Zhang Long Bai Jia-Can Su 《Military Medical Research》 2025年第4期600-632,共33页
In addition to its recognized role in providing structural support, bone plays a crucial role in maintaining the functionality and balance of various organs by secreting specific cytokines(also known as osteokines). T... In addition to its recognized role in providing structural support, bone plays a crucial role in maintaining the functionality and balance of various organs by secreting specific cytokines(also known as osteokines). This reciprocal influence extends to these organs modulating bone homeostasis and development, although this aspect has yet to be systematically reviewed. This review aims to elucidate this bidirectional crosstalk, with a particular focus on the role of osteokines. Additionally, it presents a unique compilation of evidence highlighting the critical function of extracellular vesicles(EVs) within bone-organ axes for the first time. Moreover, it explores the implications of this crosstalk for designing and implementing bone-on-chips and assembloids, underscoring the importance of comprehending these interactions for advancing physiologically relevant in vitro models. Consequently, this review establishes a robust theoretical foundation for preventing, diagnosing, and treating diseases related to the bone-organ axis from the perspective of cytokines, EVs, hormones, and metabolites. 展开更多
关键词 Bone-organ axes bidirectional crosstalk Cytokines Osteokines Extracellular vesicles(EVs) HORMONES Metabolites
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Bidirectional regulation of the gut microbiome-immune axis in the immune microenvironment of colorectal cancer and targeted interventions
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作者 Xin-Xin Liu Bing Yang Dong-Xin Tang 《World Journal of Gastrointestinal Oncology》 2025年第10期124-137,共14页
The initiation and progression of colorectal cancer(CRC)are profoundly influenced by the complex interplay between the gut microbiota and the immune system,underscoring the clinical importance of exploring the bidirec... The initiation and progression of colorectal cancer(CRC)are profoundly influenced by the complex interplay between the gut microbiota and the immune system,underscoring the clinical importance of exploring the bidirectional regulatory mechanisms of the microbiota-immune axis within the CRC immune microenvironment.Emerging evidence indicates that the composition and functional capacity of the gut microbiota play a vital role in modulating the host’s immune responses,while the immune system,in turn,can reciprocally regulate the structure and function of the microbiota.Despite significant insights into the role of the microbiota-immune axis in CRC progression,several critical questions remain unanswered-including how microbial heterogeneity affects therapeutic outcomes and the specific consequences of dysregulated regulatory mechanisms on the immune microenvironment.This review aims to provide a comprehensive analysis of the compositional features of the CRC immune microenvironment,examine the bidirectional molecular mechanisms underpinning the microbiotaimmune axis,and evaluate the potential of targeted therapeutic strategies,thereby offering novel research perspectives and clinical applications for CRC treatment. 展开更多
关键词 Microbiota-immune axis Colorectal cancer Immune microenvironment bidirectional regulation Targeted intervention
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