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Nano Research 2010年第5期3卷 350-355页

作者： Hui Cao Jing Ma yi luo Department of Theoretical Chemistry School of BiotechnologyRoyal Institute of TechnologyS-10691 StockholmSweden School of Chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of Ministry of EducationNanjing UniversityNanjing 210093China

We have combined molecular dynamics simulations with first-principles calculations to study electron transport in a single molecular junction of perylene tetracarboxylic diimide (PTCDI) in aqueous solution under external electric gate fields. It is found that the statistics of the molecular conductance are very sensitive to the strength of the electric field. The statistics of the molecular conductance are strongly associated with the thermal fluctuation of the water molecules around the PTCDI molecule. Our simulations reproduce the experimentally observed three orders of magnitude enhancement of the conductance, as well as the temperature dependent conductance, under the electrochemical gates. The effects of the molecular polarization and the dipole rearrangement of the aqueous solution are also discussed.

关键词： Molecular junction field effect solvent effect temperature effect statistical behavior

基于边界强化混合采样的两阶段电力系统暂态稳定评估

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电力自动化设备 2024年第4期44卷 143-150页

作者：周生存罗毅易煊承吴亚宁李丁雷成华中科技大学电气与电子工程学院强电磁工程与新技术国家重点实验室湖北武汉430074 南方电网能源发展研究院有限责任公司广东广州510530

受制于样本固有的不平衡性,基于数据挖掘的暂态稳定预测方法不易用于工程实践,为此,提出一种基于边界强化混合采样的两阶段暂态稳定评估模型。在第1阶段,利用预训练的级联卷积神经网络模型确定边界和非边界样本集,利用条件生成对抗网络... 详细信息

受制于样本固有的不平衡性,基于数据挖掘的暂态稳定预测方法不易用于工程实践,为此,提出一种基于边界强化混合采样的两阶段暂态稳定评估模型。在第1阶段,利用预训练的级联卷积神经网络模型确定边界和非边界样本集,利用条件生成对抗网络合成边界集失稳样本,并对非边界集稳定样本进行欠采样,以实现边界强化;在第2阶段,利用混合采样后的重构样本集再训练卷积神经网络模型,以更好地挖掘失稳样本的隐含特征,并采用改进后的焦点损失函数加强模型对边界集样本的学习能力。新英格兰39节点系统与南方某省级电网的仿真结果表明,所建模型有效降低了对失稳样本的漏判率,提高了整体预测精度,在样本极不平衡的情况下仍有良好的评估性能。

关键词：边界强化混合采样暂态稳定不平衡分类卷积神经网络

Local Structures and Chemical Properties of Deprotonated Arginine

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Chinese Journal of Chemical Physics 2012年第6期25卷 681-686,I0003,I0004页

作者： Hong-bao Li Zi-jing Lin yi luo Hefei National Laboratory for Physical Sciences at the Microscale and Department of Physics University of Science and Technolo&y of China Hefei 230025 China Department of Theoretical Chemistry and Biology School of BiotechnoloEy Royal Institute ofTechnoloEy S-106 91 Stockholm Sweden

气体的 deprotonated 精氨酸的势能表面被第一原则计算系统地调查了。在 B3LYP/6-31G (d) 水平，除了几稳定的本地结构的鉴定，新全球最小被定位它是比什么更稳定的大约 6.56 kJ/mol 被报导了。deprotonated 精氨酸分子在羧化物组与 dep... 详细信息

气体的 deprotonated 精氨酸的势能表面被第一原则计算系统地调查了。在 B3LYP/6-31G (d) 水平，除了几稳定的本地结构的鉴定，新全球最小被定位它是比什么更稳定的大约 6.56 kJ/mol 被报导了。deprotonated 精氨酸分子在羧化物组与 deprotonation 有二种不同形式(咕咕叫) 。这二种形式被一个很高的精力障碍衔接并且拥有很不同的红外光谱侧面。我们的计算质子分离精力和精氨酸分子的煤气阶段的酸味被发现在对相应试验性的结果的好同意。预言的几何学，偶极子时刻，旋转常数，垂直电离精力和低精力 conformers 的红外系列将为未来是有用的试验性的大小。

关键词：去质子化精氨酸局域结构第一原理计算性质红外光谱实验测量全局极小值

Measuring cotton water status using water-related vegetation indices at leaf and canopy levels

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Journal of Arid Land 2012年第3期4卷 310-319页

作者： QiuXiang yi AnMing BAO yi luo Jin ZHAO Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

Drought is one of the major environmental threats in the world. In recent years, the damage from droughts to the environment and economies of some countries has been extensive, and drought monitoring has caused widespread concerns. Remote sensing has a proven ability to provide spatial and temporal measurements of surface properties, and it offers an opportunity for the quantitative assessment of drought indicators such as the vegetation water content at different levels. In this study, sites of cotton field in Shihezi, Xinjiang, Northwest China were sampled. Four classical water content parameters, namely the leaf equivalent water thickness （EWT^e,f）, the fuel moisture content （FMC）, the canopy equivalent water thickness （EVVmcanopy） and vegetation water content （VWC） were evaluated against seven widely-used water-related vegetation indices, namely the NDII （normalized difference infrared index）, NDWI2130 （normalized difference water index）, NDVI （normalized difference vegetation index）, MSI （moisture stress index）, SRWI （simple ratio water index）, NOWI1240 （normalized difference water index） and WI （water index）, respectively. The results proved that the relationships between the water-related vegetation indices and EWTleaf were much better than that with FMC, and the relationships between vegetation indices and EWTcanopy were better than that with VWC. Furthermore, comparing the significance of all seven water-related vegetation in- dices, WI and NDII proved to be the best candidates for EWT detecting at leaf and canopy levels, with R2 of 0.262 and 0.306 for EWTlear-WI and EWTcanopy-NDII linear models, respectively. Besides, the prediction power of linear regression technique （LR） and artificial neural network （ANN） were compared using calibration and validation dataset, respectively. The results indicated that the performance of ANN as a predictive tool for water status meas- uring was as good as LR. The study should further our understanding of the relationships between water-related vegetation indices and w

关键词： artificial neural network cotton linear regression vegetation indices water parameters

Blockade of angiopoietin-2/Tie2 signaling pathway specifically promotes inflammation-induced angiogenesis in mouse cornea

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International Journal of Ophthalmology(English edition) 2017年第8期10卷 1187-1194页

作者： Zhi-Xin Yan yi luo Ning-Fei Liu Department of Plastic & Burn Surgery Affiliated Hospitalof Jiangsu University Zhenjiang 212001 Jiangsu ProvinceChina Lymphology Center of Department of Plastic & ReconstructiveSurgery Shanghai Ninth People's Hospital Shanghai JiaoTong University School of Medicine Shanghai 200011 China

AIM： To investigate angiopoietin-2 （Ang-2）/Tie2 signaling pathway involving in inflammatory angiogenesis. METHODS： Three interrupted 11-0 nylon sutures were placed into the corneal stroma of BALB/c mice （6wk old） to induce inflammatory neovascularization. Expression of Ang-2 and Tie2 protein on neovascularization were examined by immunofluorescence. The dynamic expression of Ang-2 mRNA on neovascularization was examined by quantitative real-time reverse transcriptase-polymerase chain reaction （RT-PCR）. Finally, the mouse model of suture- induced corneal neovascularization was used to assess the role of Ang-2/Tie2 signaling pathway in inflammatory angiogenesis by systemic application of L1-10, an Ang-2 specific inhibitor. Mouse corneal hemangiogenesis were evaluated by whole mount immunofluorescence. RESULTS： Both Ang-2 and Tie2 were expressed on newly generated blood vessels in inflammatory cornea. Ang-2 expression was gradually upregulated around 2wk following injury, which was concurrent with an increased number of blood vessels. Blockade of Ang-2/Tie2 signaling pathway obviously promoted angiogenesis in inflammatory cornea. CONCLUSION： Ang-2/Tie2 signaling pathway seems to play an important role during angiogenesis in inflammatory cornea. This may open new therapeutic applications in pathological processes such as corneal graft survival, wound healing and carcinogenesis.

关键词： angiogenesis angiopoietin-2 Tie2 inflammation

To image,or not to image:class-specific diffractive cameras with all-optical erasure of undesired objects

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eLight 2022年第1期2卷 165-184页

作者： Bijie Bai yi luo Tianyi Gan Jingtian Hu Yuhang Li yifan Zhao Deniz Mengu Mona Jarrahi Aydogan Ozcan Electrical and Computer Engineering Department University of CaliforniaLos AngelesCA 90095USA Bioengineering Department University of CaliforniaLos Angeles 90095USA California NanoSystems Institute(CNSI) University of CaliforniaLos AngelesCAUSA

Privacy protection is a growing concern in the digital era,with machine vision techniques widely used throughout public and private settings.Existing methods address this growing problem by,e.g.,encrypting camera images or obscuring/blurring the imaged information through digital algorithms.Here,we demonstrate a camera design that performs class-specific imaging of target objects with instantaneous all-optical erasure of other classes of objects.This diffractive camera consists of transmissive surfaces structured using deep learning to perform selective imaging of target classes of objects positioned at its input field-of-view.After their fabrication,the thin diffractive layers collectively perform optical mode filtering to accurately form images of the objects that belong to a target data class or group of classes,while instantaneously erasing objects of the other data classes at the output field-of-view.Using the same framework,we also demonstrate the design of class-specific permutation and class-specific linear transformation cameras,where the objects of a target data class are pixel-wise permuted or linearly transformed following an arbitrarily selected transformation matrix for all-optical class-specific encryption,while the other classes of objects are irreversibly erased from the output image.The success of class-specific diffractive cameras was experimentally demonstrated using terahertz(THz)waves and 3D-printed diffractive layers that selectively imaged only one class of the MNIST handwritten digit dataset,all-optically erasing the other handwritten digits.This diffractive camera design can be scaled to different parts of the electromagnetic spectrum,including,e.g.,the visible and infrared wavelengths,to provide transformative opportunities for privacy-preserving digital cameras and task-specific data-efficient imaging.

关键词： optical image specific

An improved influence function method for predicting subsidence caused by longwall mining operations in inclined coal seams

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International Journal of Coal Science & Technology 2015年第3期2卷 163-169页

作者： yi luo Department of Mining Engineering West VirginiaUniversity Morgantown WV USA

Prediction of surface subsidence caused by longwall mining operation in inclined coal seams is often very challenging. The existing empirical prediction methods are inflexible for varying geological and mining conditions. An improved influence function method has been developed to take the advantage of its fundamentally sound nature and flexibility. In developing this method, the original Knothe function has been transformed to produce a continuous and asymmetrical subsidence influence function. The empirical equations for final subsidence parameters derived from collected longwall subsidence data have been incorporated into the mathematical models to improve the prediction accuracy. A number of demonstration cases for longwall mining operations in coal seams with varying inclination angles, depths and panel widths have been used to verify the applicability of the new subsidence prediction model.

关键词：影响函数法急倾斜煤层沉陷预测长壁开采业务最终沉降经验预测采矿条件

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考虑数据缺失的图注意力网络暂态稳定评估

中国电力 2024年第5期57卷 157-167页

作者：周生存罗毅易煊承吴亚宁李丁熊逸强电磁工程与新技术国家重点实验室(华中科技大学电气与电子工程学院) 湖北武汉430074

基于人工智能的暂态稳定评估模型的性能高度依赖于系统的可观测性,而通信延迟和相量测量单元(phasor measurement units,PMU)故障等因素易导致数据缺失,使模型的评估性能下降。针对该问题,提出了一种基于图注意力网络(graph attention n... 详细信息

基于人工智能的暂态稳定评估模型的性能高度依赖于系统的可观测性,而通信延迟和相量测量单元(phasor measurement units,PMU)故障等因素易导致数据缺失,使模型的评估性能下降。针对该问题,提出了一种基于图注意力网络(graph attention network,GAT)的暂态稳定评估模型。首先,根据原始网络拓扑及PMU配置方案获得表征系统可观测性的掩码矩阵,在任意PMU缺失的条件下,利用掩码矩阵训练模型;其次,通过GAT网络的多头注意力机制提取输入节点的时空信息,利用不同的权重聚合目标节点的邻域特征,实现对可观测数据的充分利用;最后,利用焦点损失函数加强模型对失稳样本的学习能力。仿真结果表明,所提方法可以最大限度地利用可观测数据,具有高精度和强鲁棒性,并且不受网络拓扑的限制,易于迁移。

关键词：暂态稳定评估数据缺失图注意力网络掩码矩阵 PMU故障

数字公共外交的群际接触途径:现状、问题与优化路径——以“洋网红”的视频传播实践为例

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长江师范学院学报 2024年第4期40卷 87-95页

作者：罗艺武汉大学新闻与传播学院湖北武汉430072

随着互联网技术发展,国际化社交视频平台成为“洋网红”向全球受众分享在中国的经历与感悟的重要渠道。基于群际接触理论,以bilibili和YouTube两大社交平台上洋网红发布的有关视频为研究对象,通过内容分析法对“洋网红”视频中呈现的群... 详细信息

随着互联网技术发展,国际化社交视频平台成为“洋网红”向全球受众分享在中国的经历与感悟的重要渠道。基于群际接触理论,以bilibili和YouTube两大社交平台上洋网红发布的有关视频为研究对象,通过内容分析法对“洋网红”视频中呈现的群际接触行为外在表征和内在规律进行深入探究。研究发现:“洋网红”群体在分布上呈现明显的不均衡和多元性不足的特征,亲密感和相似性是触发“洋网红”与中国人群体进行接触的主要因素;此外,“洋网红”视频在连接中外群体和弘扬中华文化方面具有积极作用。因此,建议鼓励“洋网红”创作,出台相关政策引导和规范其创作内容,将“洋网红”的视频实践作为数字公共外交的有效途径,推动中外群体之间的交流与理解。

关键词：媒介群际接触洋网红 YouTube视频数字公共外交

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乾隆《潼川府志》文献学价值探析

四川图书馆学报 2024年第2期 89-94页

作者：罗伊吉林大学古籍研究所长春130012

乾隆《潼川府志》是在清代修志高潮下编纂的一部志书,不仅具有一定史料价值,更具有重要的文献学价值,主要体现在其编纂审慎、征文考据、保存佚文三个方面。是志在体例上自成一家,对所收地方文献详加考证,并辑存了一些失传文献,通过考辨... 详细信息

乾隆《潼川府志》是在清代修志高潮下编纂的一部志书,不仅具有一定史料价值,更具有重要的文献学价值,主要体现在其编纂审慎、征文考据、保存佚文三个方面。是志在体例上自成一家,对所收地方文献详加考证,并辑存了一些失传文献,通过考辨相关文献,对深入研究清代地方志编纂情况,以及清代潼川府地区的历史文化风貌提供帮助。

关键词：乾隆《潼川府志》文献学地方志地方文献