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系统仿真技术 2018年第1期14卷 25-29,48页

作者：李艳屈正庚商洛学院经济管理学院陕西商洛726000 商洛学院数学与计算机应用学院陕西商洛726000

分析了影响学习者特征的重要因素,包括起点水平、知识结构、学习态度、学习动机和学习风格。利用层次分析法(AHP)对5个因素进行定量与定性分析,计算得到学习者特征分值。研究结果表明:该分析方法可以为集体化、个别化教学提供理论指导。

关键词：学习者特征层次分析法(AHP) 知识结构学习态度学习动机

BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

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Research in Astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： Zhong-Mu li Cai-yan Mao Institute of Astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess con

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters

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基于生态建筑的农业垂直建筑模式

农业工程 2018年第1期8卷 50-52页

作者：李燕武彦生昆明冶金高等专科学校建工学院昆明650031 昆明冶金高等专科学校环境工程学院昆明650031

随着城市对人居环境和能源要求的提出,构建更具生态化的都市,从而提高城市利用空间和农业生产效率成为重点。在分析传统都市农业存在的问题和都市农业垂直模式的重要性前提下,提出一种都市农业垂直建筑模式。以实际的设计案例作为研究背... 详细信息

随着城市对人居环境和能源要求的提出,构建更具生态化的都市,从而提高城市利用空间和农业生产效率成为重点。在分析传统都市农业存在的问题和都市农业垂直模式的重要性前提下,提出一种都市农业垂直建筑模式。以实际的设计案例作为研究背景,对某建筑+都市农业技术进行全面设计,并就其体现出的经济效益进行综合评价,为当前都市农业中垂直建筑模式的推广应用提供借鉴与参考。

关键词：都市农业生态建筑垂直模式

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高频电磁场下柚皮中天然食用色素的浸取

食品科技 2004年第9期29卷 59-61页

作者：李巧玲李琳牟德华李艳康明丽河北科技大学生物工程学院石家庄050018 华南理工大学食品与生物工程学院广州510640

以柚皮为原料,以水为介质,在微波条件下直接从柚皮中提取天然色素。微波浸取与传统方法相比,具有提取率高、节省时间、能源消耗小、安全无污染等特点。扫描电子显微技术分析证明,微波固液浸取的机理与传统加热浸取的机理是不同的。

关键词：高频电磁场天然食用色素浸取机理

Model architecture level privacy leakage in neural networks

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Science China(Information Sciences) 2024年第3期67卷 20-32页

作者： yan li Hongyang yan Teng HUANG Zijie PAN Jiewei LAI Xiaoxue ZHANG Kongyang CHEN Jin li Institute of Artificial Intelligent and Blockchain Guangzhou University Pazhou Lab

Privacy leakage is one of the most critical issues in machine learning and has attracted growing interest for tasks such as demonstrating potential threats in model attacks and creating model *** recent years, numerous studies have revealed various privacy leakage risks(e.g., data reconstruction attack, membership inference attack, backdoor attack, and adversarial attack) and several targeted defense approaches(e.g., data denoising, differential privacy, and data encryption). However, existing solutions generally focus on model parameter levels to disclose(or repair) privacy threats during the model training and/or model interference process, which are rarely applied at the model architecture level. Thus, in this paper, we aim to exploit the potential privacy leakage at the model architecture level through a pioneer study on neural architecture search(NAS) paradigms which serves as a powerful tool to automate a neural network *** investigating the NAS procedure, we discover two attack threats in the model architecture level called the architectural dataset reconstruction attack and the architectural membership inference attack. Our theoretical analysis and experimental evaluation reveal that an attacker may leverage the output architecture of an ongoing NAS paradigm to reconstruct its original training set, or accurately infer the memberships of its training set simply from the model architecture. In this work, we also propose several defense approaches related to these model architecture attacks. We hope our work can highlight the need for greater attention to privacy protection in model architecture levels(e.g., NAS paradigms).

关键词： neural architecture search data reconstruction attack membership inference attack

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过表达DLL3促进人胃癌细胞的增殖

南方医科大学学报 2018年第1期38卷 14-19页

作者：胡冰心叶健斌邱晓媚林彦青吴丹琳温俊杰罗美群宁立军李妍宁云山南方医科大学检验与生物技术学院生物治疗研究所广东广州510515 珠海南医大生物医药公共服务平台有限公司广东珠海519090

目的构建人全长DLL3的真核表达质粒,并分析上调和下调DLL3对人胃癌细胞增殖的影响。方法采用PCR扩增人全长DLL3基因并克隆至真核表达载体pCMV-Tag4中,通过酶切及测序鉴定后,瞬时转染HEK293T细胞,并以转染pCMV-Tag4质粒和无转染HEK293T... 详细信息

目的构建人全长DLL3的真核表达质粒,并分析上调和下调DLL3对人胃癌细胞增殖的影响。方法采用PCR扩增人全长DLL3基因并克隆至真核表达载体pCMV-Tag4中,通过酶切及测序鉴定后,瞬时转染HEK293T细胞,并以转染pCMV-Tag4质粒和无转染HEK293T细胞分别为阴性对照和空白对照,实时荧光定量PCR(qRT-PCR)和Western blot鉴定人全长DLL3基因的表达;进一步通过qRT-PCR和Western blot检测人DLL3在人正常口腔上皮细胞GES-1和AGS等3株胃癌细胞中的表达差异;当人DLL3/pCMV-Tag4瞬时转染3株胃癌细胞后,利用MTT检测DLL3过表达后胃癌细胞的增殖;同时,特异性人DLL3si RNA转染人胃癌细胞MGC803和MKN45,利用MTT检测DLL3下调后胃癌细胞的增殖。结果成功构建了人全长DLL3/pCMV-Tag4重组质粒,转染HEK293T细胞24 h后,qRT-PCR和Western blot表明DLL3在m RNA和蛋白水平上的表达显著高于对照组;MTT细胞增殖实验显示:过表达DLL3促进胃癌细胞的增殖,下调DLL3后抑制胃癌细胞的增殖。结论成功构建了人全长DLL3/pCMV-Tag4真核表达质粒并在HEK293T细胞中获得表达,过表达DLL3促进胃癌细胞的增殖,下调DLL3抑制胃癌细胞的增殖,本研究为以DLL3为新靶点对胃癌进行靶向治疗提供新思路。

关键词：人DLL3 真核表达胃癌细胞增殖

Friction between a single platelet and fibrinogen

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Friction 2024年第10期12卷 2344-2354页

作者： Yuhe WANG yan li Shuguang ZHANG Haosheng CHEN Yongjian li State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Key Laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing 100083China

Friction has been considered to mediate physiological activities of cells,however,the biological friction between a single cell and its ligand-bound surface has not been thoroughly ***,we established a friction model for single cells based on an atomic force microscopy(AFM)combined with an inverted fluorescence microscopy(IFM)to study the friction between a highly sensitive platelet and fibrinogen-coated *** study revealed that the friction between the platelet and fibrinogen-coated tip is mainly influenced by specific ligand–receptor ***,we modeled the biological friction,which consists of specific interaction,non-specific interaction,and mechanical ***,the results suggested that the velocity can also affect specific ligand–receptor interactions,resulting in the friction change and platelet adhesion to fibrinogen *** study built a friction model between a single cell and its ligand-bound surface and provided a potential method to study the biological friction by the combination of AFM and IFM.

关键词： friction single cell platelet fibrinogen atomic force microscopy(AFM)

Fusion of a rice endogenous N-methylpurine DNA glycosylase to a plant adenine base transition editor ABE8e enables A-toK base editing in rice plants

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aBIOTECH 2024年第2期5卷 127-139页

作者： Yucai li Shaoya li Chenfei li Chen Zhang Lei yan Jingying li Yubing He yan Guo Lanqin Xia Institute of Crop Sciences(ICS) Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193China Hainan Yazhou Bay Seed Laboratory/National Nanfan Research Institute(Sanya) CAASSanya 572024China

Engineering of a new type of plant base editor for simultaneous adenine transition and transversion within the editing window will greatly expand the scope and potential of base editing in directed evolution and crop ***,we isolated a rice endogenous hypoxanthine excision protein,N-methylpurine DNA glycosylase(OsMPG),and engineered two plant A-to-K(K=G or T)base editors,rAKBE01 and rAKBE02,for simultaneous adenine transition and transversion base editing in rice by fusing OsMPG or its mutant mOsMPG to a plant adenine transition base editor,*** further coupled either OsMPG or mOsMPG with a transactivation factor VP64 to generate rAKBE03 and rAKBE04,*** these four rAKBEs,at five endogenous loci in rice protoplasts,indicated that rAKBE03 and rAKBE04 enabled higher levels of A-to-G base transitions when compared to ABE8e and ***,whereas rAKBE01 only enabled A-to-C/T editing at one endogenous locus,in comparison with rAKBE02 and rAKBE03,rAKBE04 could significantly improve the A-to-C/T base transversion efficiencies by up to 6.57-and 1.75-fold in the rice protoplasts,***,although no stable lines with A-to-C transversion were induced by rAKBE01 and rAKBE04,rAKBE04 could enable simultaneous A-to-G and A-to-T transition and transversion base editing,at all the five target loci,with the efficiencies of A-to-G transition and A-to-T transversion editing ranging from 70.97 to 92.31%and 1.67 to 4.84%in rice stable lines,***,these rAKBEs enable different portfolios of editing products and,thus,now expands the potential of base editing in diverse application scenario for crop improvement.

关键词： Rice(Oryza sativa L) Rice N-methylpurine DNA glycosylase(OsMPG) A-to-K base editor(AKBE) Transactivation module VP64

Enhancing Tea Leaf Disease Identification with lightweight MobileNetV2

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Computers, Materials & Continua 2024年第7期80卷 679-694页

作者： Zhilin li Yuxin li Chunyu yan Peng yan Xiutong li Mei Yu Tingchi Wen Benliang Xie College of Big Data and Information Engineering Guizhou UniversityGuiyang550025China Power Semiconductor Device Reliability Engineering Center of the Ministry of Education Guiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China The Mushroom Research Centre Guizhou UniversityGuiyang550025China The Engineering Research Center of Southwest Bio-Pharmaceutical Resources Ministry of EducationGuizhou UniversityGuiyang550025China

Diseases in tea trees can result in significant losses in both the quality and quantity of tea *** monitoring can help to prevent the occurrence of large-scale diseases in tea ***,existingmethods face challenges such as a high number of parameters and low recognition accuracy,which hinders their application in tea plantation monitoring *** paper presents a lightweight I-MobileNetV2 model for identifying diseases in tea leaves,to address these *** proposed method first embeds a Coordinate Attention(CA)module into the originalMobileNetV2 network,enabling the model to locate disease regions ***,a Multi-branch Parallel Convolution(MPC)module is employed to extract disease features across multiple scales,improving themodel’s adaptability to different disease ***,the AutoML for Model Compression(AMC)is used to compress themodel and reduce computational *** results indicate that our proposed algorithm attains an average accuracy of 96.12%on our self-built tea leaf disease dataset,surpassing the original MobileNetV2 by 1.91%.Furthermore,the number of model parameters have been reduced by 40%,making itmore suitable for practical application in tea plantation environments.

关键词： Disease identification coordinate attention mechanism multi-scale feature extraction model pruning

Impact Performance Research of Re-Entrant Octagonal Negative Poisson’s Ratio Honeycomb with Gradient Design

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 3105-3119页

作者： Yiyuan li Yongjing li Shilin yan Pin Wen Department of Engineering Structure and Mechanics Wuhan University of TechnologyWuhan430070China Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan430070China

Based on the traditional re-entrant honeycomb,a novel re-entrant octagon honeycomb(ROH)is *** deformation mode of the honeycomb under quasi-static compression is analyzed by numerical simulation,and the results are in good agreement with the experimental *** deformation modes,mechanical properties,and energy absorption characteristics of ROH along the impact and perpendicular directions gradient design are investigated under different *** results indicated that the deformation mode of ROH is affected by gradient design along the direction of impact and impact *** addition,gradient design along the direction of impact can increase the initial peak stress of ROH and accelerate its densification *** design perpendicular to the impact direction can enhance the energy absorption performance of ROH,especially for ROH,with wall thickness increasing from the inside *** to ROH with uniform wall thickness at the same relative density,ROH with a gradient design can increase the plateau stress by over *** the elevation of impact velocity,the plateau stress and specific energy absorption exhibit an upward trend,aligning with the dynamic performance pattern observed in conventional *** results can be used as a reference for the design and application of honeycomb and provide a new idea for developing more efficient and reliable energy-absorbing materials.

关键词： Re-entrant honeycomb gradient design finite element analysis additive manufacturing technologies