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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第1期33卷 121-128页

作者： Zhang Yang Xue Ping Ding Yun Jia Mingyin shi zhenwei Wang Hao Institute of Plastic Machinery and Engineering Beijing University of Chemical Technology Centre of Excellence in Engineered fiber Composite University of Southern Queensland

Noil discarded fibers from fiber production for textile industry have short length and are always considered less ***,noil ramie fibers/HDPE composite is prepared using twin-screw extruder and the dynamic mechanical and thermal properties are *** influence of ramie fiber and maleic anhydride-grafted polyolefin(MA-g-PO)on mechanical,dynamic mechanical and thermal properties is *** is observed that the tensile,flexural and impact properties of the composites treated with MA-g-PO are all improved in comparison to the untreated *** mechanical properties of the composite with MA-g-PO show an increase in the storage modulus with a higherαrelaxation peak,together with the micromorphology analysis,indicating an improved interfacial bonding between fiber and matrix by the MA-g-PO ***,the change in TGA thermograms of composite caused by MA-g-PO exhibits that the addition of MA-g-PO is also helpful to increase the thermal stability of noil ramie fiber/HDPE composites.

关键词： noil ramie fiber high density polyethylene(HDPE) mechanical properties MA-g-PO natural fi ber composites

Au-catalyzed neighboring hydroxymethyl group directed cycloaddition of alkyne with diazadienes:Synthesis of polysubstituted pyrroles

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Chinese Chemical Letters 2023年第1期34卷 342-346页

作者： zhenwei shi Wenxiu Mao Zhenning Yang Shuzhe Sun Chen-Ho Tung Zhenghu Xu School of Chemistry and Chemical Engineering Shandong UniversityJi’nan 250100China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China

Polysubstituted pyrroles are very important scaffolds in many bioactive natural products and synthetic ***,a new gold-catalyzed cycloaddition of alkynes with azadienes to access tetrasubstituted pyrroles is *** neighboring hydroxylmethyl group serves a very important directing group through an addition/cycloaddition/elimination *** polysubstituted pyrroles were synthesized in good yields under mild conditions in one step,and tricyclic pyrrole containing heterocycles were easily obtained through derivatization.

关键词： Pyrrole Au Neighboring group Cascade reaction Synthetic method

Few-Shot Remote Sensing Novel View Synthesis with Geometry Constraint NeRF

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Guidance,Navigation and Control 2024年第3期4卷 70-91页

作者： Jiaming Kang Keyan Chen Zhengxia Zou zhenwei shi Image Processing Center School of Astronautics Beihang University Department of Guidance Navigation and Control School of Astronautics Beihang University

Novel View Synthesis(NVS) is an important task for 3D interpretation in remote sensing scenes, which also benefits vicinagearth security by enhancing situational awareness capabilities. Recently, NVS methods based on Neural Radiance Fields(Ne RFs) have attracted increasing attention for self-supervised training and highly photo-realistic synthesis ***, it is still challenging to synthesize novel view images in remote sensing scenes, given the complexity of land covers and the sparsity of input multi-view images. In this paper, we propose a novel NVS method named FRe SNe RF, which combines Image-Based Rendering(IBR) and Ne RF to achieve high-quality results in remote sensing scenes with sparse input. We effectively solve the degradation problem by adopting the sampling space annealing ***, we introduce depth smoothness based on the segmentation mask to constrain the scene geometry. Experiments on multiple scenes show the superiority of our proposed FRe SNe RF over other methods.

关键词： image-based rendering neural radiance field novel view synthesis remote sensing Vicinagearth security

A nowcasting model for the prediction of typhoon tracks based on a long short term memory neural network

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Acta Oceanologica Sinica 2018年第5期37卷 8-12页

作者： GAO Song ZHAO Peng PAN Bin LI Yaru ZHOU Min XU Jiangling ZHONG Shan shi zhenwei North China Sea Marine Forecasting Center of State Oceanic Administration State Oceanic Administration Qingdao 266061 China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266061 China Image Processing Center School of Astronautics Beihang University Beijing 100191 China

It is of vital importance to reduce injuries and economic losses by accurate forecasts of typhoon tracks. A huge amount of typhoon observations have been accumulated by the meteorological department, however, they are yet to be adequately utilized. It is an effective method to employ machine learning to perform forecasts. A long short term memory（LSTM） neural network is trained based on the typhoon observations during 1949–2011 in China＇s Mainland, combined with big data and data mining technologies, and a forecast model based on machine learning for the prediction of typhoon tracks is developed. The results show that the employed algorithm produces desirable 6–24 h nowcasting of typhoon tracks with an improved precision.

关键词： typhoon tracks machine learning LSTM big data

基于Transformer与注意力机制的肺部肿瘤分割方法

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广东工业大学学报 2025年第1期42卷 24-32页

作者：曾安王丹杨宝瑶张小波石镇维刘再毅潘丹广东工业大学计算机学院广东广州510006 广东工业大学自动化学院广东广州510006 广东省人民医院广东广州510080 广东技术师范大学电子与信息学院广东广州510665

肺部肿瘤的准确分割对于肿瘤的诊断和治疗具有重要作用,然而肺部肿瘤分割中存在病灶与周围组织的对比度低、肿瘤与正常组织易粘连和背景噪声大等问题。针对这些问题,本文提出了一种基于Transformer和注意力机制的肺部肿瘤分割方法。在Tr... 详细信息

肺部肿瘤的准确分割对于肿瘤的诊断和治疗具有重要作用,然而肺部肿瘤分割中存在病灶与周围组织的对比度低、肿瘤与正常组织易粘连和背景噪声大等问题。针对这些问题,本文提出了一种基于Transformer和注意力机制的肺部肿瘤分割方法。在Transformer编码器阶段引入全局和局部的注意力机制,使得网络可以同时关注全局和局部的上下文信息;在跳跃连接阶段,使用通道优先卷积注意力机制,可以增强复杂病灶的空间感知能力和降低通道维度冗余,从而提高肿瘤的分割精度。在私有数据集GDPH和公共数据集LUNG1上的测试结果表明,本文方法相比其他8种分割方法,Dice指标在两个数据集上表现最优,分别为90.96%和88.18%,可以为临床的诊疗提供可靠辅助。

关键词：肺部肿瘤医学图像分割卷积神经网络 Transformer 注意力机制

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The effect of Pickering emulsion adjuvants on the immune efficacy of the COVID-19 polypeptide vaccine

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ChemPhysMater 2023年第3期2卷 259-266页

作者： Zhuanqing Huang Qi Sun Haoyuan shi Sen Yang Yuanyuan Li Yue Ma Fei Yang zhenwei shi Yalong Yang Ying Zhang Hui Gong Fenghua Xu Pharmaceutical Sciences Research Division Department of PharmacyMedical Supplies CentrePLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China Chinese People’s Armed Police Force Hospital of Beijing Beijing 100600China

Pickering emulsions were prepared by phacoemulsification in an ice water bath with squalene as the oil phase and an aluminum adjuvant as the particle *** effects of formulation and process conditions on the size and distribution of the Pickering emulsions were *** emulsions prepared under the optimal prescription and process conditions were mixed with a peptide antigen to obtain a peptide *** optimal prescription and process condition of the Pickering emulsion is as follows:squalene as the oil phase,ultra-pure water as the water phase with 5 mg/mL aluminum adjuvant,and an ultrasonication time of 4 min at 200 W ***/c mice were immunized with the peptide vaccine,and the ability of the Pickering emulsion as an immunological adjuvant to improve the efficacy of the peptide vaccine was *** optimal conditions,a Pickering emulsion with a small particle size(430.8 nm),uniform distribution(polydispersion index of 16.9%),and zeta potential of 31.5 mV,was *** results showed that the serum specific antibody level in the vaccinated group reached 1×104 after three *** proportion of CD4+T cells and CD4/CD8 cells was significantly higher(P<0.05)in the vaccinated groups than the blank control ***,cytokine(TNF-𝛼)secretion decreased in the aluminum adjuvant and Pickering emulsion groups but increased in the Freund’s adjuvant *** three vaccinated groups of mice exhibited low but detectable levels of IFN-𝛾secretion.

关键词： Pickering emulsions Ultrasonic emulsification Immunologic adjuvant COVID-19 Polypeptide vaccine

Research on visual differences of exits of different grades of tunnels based on machine learning

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Digital Transportation and Safety

Digital Transportation and Safety 2024年第3期3卷 75-81页

作者： Fangtong Jiao zhenwei shi Lingyu Li Wenpin Xu Qing Lan School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo 255000ShandongChina Department of Transportation Engineering Hebei University of Water Resources and Electric EngineeringCangzhou 061001HebeiChina Hebei Higher Institute of Transportation Infrastructure Research and Development Center for Digital and Intelligent Technology Application Cangzhou 061001HebeiChina

Tunnels are vital in connecting crucial transportation hubs as transportation infrastructure *** in tunnel design standards and driving conditions across different levels directly impact driver visual perception and traffic *** study employs a Gaussian hybrid clustering machine learning model to explore driver gaze patterns in highway tunnels and *** utilizing contour coefficients,the optimal number of classification clusters is *** of driver visual behavior across tunnel levels,focusing on gaze point distribution,gaze duration,and sweep speed,was *** indicate freeway tunnel exits exhibit three distinct fixation point categories aligning with Gaussian distribution,while highway tunnels display four such ***,in both tunnel types,65%of driver gaze is concentrated on the near area ahead of their *** emerge in highway tunnels due to oncoming traffic,leading to 13.47%more fixation points and 0.9%increased fixation time in the right lane compared to regular highway tunnel ***,scanning speeds predominantly fall within the 0.25-0.3 range,accounting for 75.47%and 31.14%of the total sweep speed.

关键词： Traffic safety Tunnel exit Machine learning model Fixation characteristics Scanning characteristics

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图像超分辨重建算法综述

数据采集与处理 2020年第1期35卷 1-20页

作者：史振威雷森北京航空航天大学宇航学院图像处理中心

图像超分辨重建是一种提升图像分辨率的图像处理技术,而超分辨问题是一个难解的欠定问题,近些年来研究人员主要采用基于学习的方法,从大量数据中学习图像先验信息,以实现对解空间的约束。本文介绍了近20年来主流的图像超分辨重建算法,... 详细信息

图像超分辨重建是一种提升图像分辨率的图像处理技术,而超分辨问题是一个难解的欠定问题,近些年来研究人员主要采用基于学习的方法,从大量数据中学习图像先验信息,以实现对解空间的约束。本文介绍了近20年来主流的图像超分辨重建算法,主要分为基于传统特征的方法和基于深度学习的方法。对于传统的超分辨重建算法,阐述了基于邻域嵌入的方法、基于稀疏表示的方法以及基于局部线性回归的方法。对于基于深度学习的超分辨重建算法,详细总结了网络模型结构设计、上采样方式、损失函数形式以及复杂条件下的算法设计4个方面。此外,本文简要分析了超分辨重建技术在视频超分辨、遥感图像超分辨以及在视觉高层任务方面的应用。最后,本文展望了图像超分辨重建技术的未来发展方向。

关键词：图像超分辨邻域嵌入稀疏表示局部线性回归深度学习