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China Foundry 2025年第1期22卷 33-44页

作者： Wei yuan Hai-dong Zhao Xu shen Chun Zou yuan Liu Qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification

Hausdorff Measure of Space Anisotropic Gaussian Processes with Non-stationary Increments

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 114-132页

作者： Jun WANG Zhen-long CHEN Wei-jie yuan Guang-jun shen School of Mathematics and Physics Anhui Polytechnic UniversityWuhu 241000China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018China Department of Mathematics Anhui Normal UniversityWuhu 241000China

Let X={X(t),t∈R+} be a centered space anisotropic Gaussian process values in R^(d) with non-stationary increments,whose components are independent but may not be identically *** certain conditions,then almost surely c_(1)≤ϕ-m(X([0,1]))≤c_(2),where ϕ denotes the exact Hausdorff measure associated with function ϕ(s)=s1/α_(k)+Σ_(i=1)k(1-αi/αk)log log 1/s for some 1≤k≤d,(α_(1),…,α_(d))∈(0,1]^(d).We also obtain the exact Hausdorff measure of the graph of X on[0,1].

关键词： Hausdorff measure self-similar Gaussian processes non-stationary increment Lamperti theorem

Gazing-detection of human eyes based on SVM

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Optoelectronics Letters 2005年第1期1卷 65-68页

作者： LI Su-mei ZHANG Yan-xin CHANG sheng-jiang shen jin-yuan Institute of Modem Optics and Key Laboratory of Opto-electronics Information Technical Science EMC Nankai University Tianjin 300071 China

A method for gazing-detection of human eyes using Support Vector Machine （SVM） based on statistic leaming theory （SLT） is proposed. According to the criteria of structural risk minimization of SVM,the errors between sample-data and model-data are minimized and the upper bound of predicting error of the model is also reduced. As a result,the generalization ability of the model is much improved. The simulation results show that, when limited training samples are used, the correct recognition rate of the tested samples can be as high as 100% ,which is much better than some previous results obtained by other methods. The higher processing speed enables the system to distinguish gazing or not-gazing in real-time.

关键词：人类眼睛凝视检测向量支持装置识别系统

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高炮炮兵训练计算机辅助模拟系统

华东理工大学学报（自然科学版） 2005年第4期31卷 542-545页

作者：沈晋源宋协辰沈新民上海应用技术学院上海200235

介绍了一个高炮炮兵训练计算机辅助模拟系统,并阐明了系统的开发实施过程。系统营造了真实性很强的全天候训练环境,保证了部队经常有效的军事训练,不仅提高了部队的训练水平,而且降低了部队的训练成本。项目开发达到了预期的目标,具有... 详细信息

介绍了一个高炮炮兵训练计算机辅助模拟系统,并阐明了系统的开发实施过程。系统营造了真实性很强的全天候训练环境,保证了部队经常有效的军事训练,不仅提高了部队的训练水平,而且降低了部队的训练成本。项目开发达到了预期的目标,具有很大的社会和经济效益。

关键词：高炮炮兵训练计算机辅助模拟 Delphi语言 3DMAX 数据库

Theoretical calculation on degradation mechanism of novel copolyesters under CALB enzyme

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Journal of Environmental Sciences 2025年第3期149卷 242-253页

作者： yuanyang Ren Zhiwen Cheng Luwei Cheng Yawei Liu Mingyue Li Tao yuan Zhemin shen School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants Shanghai 200240China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Poly(butylene succinate-co-furandicarboxylate)(PBSF)and poly(butylene adipateco-furandicarboxylate)(PBAF)are novel furandicarboxylic acid-based biodegradable copolyesters with great potential to replace fossil-derived terephthalic acid-based copolyesters such as poly(butylene succinate-co-terephthalate)(PBST)and poly(butylene adipate-co-terephthalate)(PBAT).In this study,quantum chemistry techniques after molecular dynamics simulations are employed to investigate the degradationmechanism of PBSF and PBAF catalyzed by Candida antarctica lipase B(CALB).Computational analysis indicates that the catalytic reaction follows a four-step mechanism resembling the ping-pong bibi mechanism,with the initial two steps being acylation reactions and the subsequent two being hydrolysis ***,the first step of the hydrolysis is identified as the rate-determining ***,by introducing single-point mutations to expand the substrate entrance tunnel,the catalytic distance of the first acylation step ***,energy barrier of the rate-determining step is decreased in the PBSF system by site-directed mutations on key residues increasing hydrophobicity of the enzyme’s active *** study unprecedently show the substrate binding pocket and hydrophobicity of the enzyme’s active site have the potential to be engineered to enhance the degradation of copolyesters catalyzed by CALB.

关键词： Poly(butylene succinate-co-furandicarboxylate) Poly(butylene adipate-co-furandicarboxylate) Candida antarctica lipase B Degradation mechanism Site-directed mutations

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用于复杂光谱数据压缩的自适应小波算法

物理学报 2007年第6期56卷 3613-3618页

作者：王凯张会常胜江申金媛南开大学现代光学研究所光电信息科学教育部重点实验室天津300071 郑州大学信息工程学院郑州450052

对于超短脉冲激光与气体相互作用产生的复杂光谱,提出了基于递归最小方差方法的自适应小波算法,实现了对该类光谱数据的高效压缩.在对三种气体,共计27组光谱数据进行压缩后,数据由最初的3968个点被压缩成124个点,压缩比为32∶1.选择其... 详细信息

对于超短脉冲激光与气体相互作用产生的复杂光谱,提出了基于递归最小方差方法的自适应小波算法,实现了对该类光谱数据的高效压缩.在对三种气体,共计27组光谱数据进行压缩后,数据由最初的3968个点被压缩成124个点,压缩比为32∶1.选择其中13组作为样本送入支持向量机神经网络进行训练,用剩下的14组进行检验,正确率为100%.

关键词：非线性荧光光谱小波分析递归最小方差算法线性神经网络

New approach to extract phase feature of 3-D objects by wavelength-scanning digital holography

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Optoelectronics Letters 2006年第2期2卷 136-138页

作者： shen jin-yuan LI Xian-guo M. K. Kim CHANG sheng-jiang College of Information Engineering Zhengzhou UniversityZhengzhou 450052China Department of Physics University of South Florida Tampa Florida 33620 USA Key Laboratory of Opto-electronics Information Technical Science EMC Institute of Modern Optics Nankai UniversityTianjin 300071 China

A new approach to extract phase feature of 3-D objects based on wavelength-scanning digital holography and numerical reconstruction technique is proposed in this paper.A number of holograms are recorded on a digital camera and reconstructed numerically by a computer with different wavelengths spaced at regular *** theoretical analysis and computer simulations demonstrate that those pixels with the same phase of a 3-D object can focus on the same reconstruction *** those pixels with different phase of a 3-D object focus on the different reconstruction *** the phase information of a 3-D object can be described by a series of reconstructed images on different planes.

关键词：数字全息术波长扫描数字相机三维重建

Formation mechanism of herpetrione self-assembled nanoparticles based on p H-driven method

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Chinese Chemical Letters 2025年第1期36卷 387-391页

作者： Yuwen Zhu Xiang Deng Yan Wu Baode shen Lingyu Hang Yuye Xue Hailong yuan Department of Pharmacy Air Force Medical CenterPLAAir Force Medical UniversityBeijing 100142China Key Laboratory of Modern Preparation of Traditional Chinese Medicine Ministry of EducationJiangxi University of Chinese MedicineNanchang 330004China

The self-assembled nanoparticles(SAN)formed during the decoction process of traditional Chinese medicine(TCM)exhibit non-uniform particle sizes and a tendency for *** group found that the p H-driven method can improve the self-assembly phenomenon of Herpetospermum caudigerum Wall.,and the SAN exhibited uniform particle size and demonstrated good *** this paper,we analyzed the interactions between the main active compound,herpetrione(Her),and its main carrier,Herpetospermum caudigerum ***(HCWP),along with their self-assembly mechanisms under different p H *** binding constants of Her and HCWP increase with rising p H,leading to the formation of Her-HCWP SAN with a smaller particle size,higher zeta potential,and improved thermal *** the contributions of hydrogen bonding and electrostatic attraction to the formation of Her-HCWP SAN increase with rising p H,the hydrophobic force consistently plays a dominant *** study enhances our scientific understanding of the self-assembly phenomenon of TCM improved by p H driven method.

关键词： Traditional Chinese medicine Nanoparticles Herpetrione Interaction pH-driven method Self-assembly Isothermal titration calorimetry

Large language models:game-changers in the healthcare industry

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Science Bulletin 2025年第3期70卷 283-286页

作者： Bin Dong Li Zhang Jiajia yuan Yang Chen Quanzheng Li Lin shen Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China Center for Machine Learning Research Peking UniversityBeijing 100871China Peking University Changsha Institute for Computing and Digital Economy Changsha 410205China Center for Data Science Peking UniversityBeijing 100871China Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)Peking University Cancer Hospital and InstituteBeijing 100142China Massachusetts General Hospital Boston 02114-2696USA Harvard Medical School Boston 02115USA

The healthcare industry faces core challenges,including increasingly complex operational processes and entities,the rapid development of medical knowledge,and the rising demand for interdisciplinary *** complexity of medical processes is evident in every aspect,from patient appointments,diagnoses,and treatments to follow-up tasks,all of which involve intricate data processing and decision-making procedures.

关键词： industry expertise evident

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一种基于卷积神经网络的烟叶等级识别方法

食品与机械 2022年第2期38卷 222-227页

作者：焦方圆申金媛郝同盟郑州大学河南郑州450001 华北水利水电大学河南郑州450045

目的:解决烟叶分级准确率不高的问题。方法:提出一种改进的基于卷积神经网络的烟叶分级模型,根据VGG16网络结构,以自定义的方式搭建网络模型;将空洞卷积代替原有的传统卷积,增加图像感受野的同时避免了图像特征的损失,并将激活函数改为L... 详细信息

目的:解决烟叶分级准确率不高的问题。方法:提出一种改进的基于卷积神经网络的烟叶分级模型,根据VGG16网络结构,以自定义的方式搭建网络模型;将空洞卷积代替原有的传统卷积,增加图像感受野的同时避免了图像特征的损失,并将激活函数改为Leaky;elu,修正数据的分布,解决ReLU函数的硬饱和问题;用41种等级的烟叶图片加以测试。结果:试验改进算法分级准确率达95.89%,与传统SVM算法相比提高了10.46%,与经典VGG16算法相比提高了7.87%,损失率最终收敛于0.13。结论:与原始模型和传统特征提取的方式相比,试验算法在烟叶分级准确率性能上有所提高。

关键词：烟叶分级深度学习激活函数空洞卷积

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