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Chinese Journal of Aeronautics 2016年第6期29卷 1575-1581页

作者： Yuan Xing tao Zhi li Haiwang tian Yitu National Key Laboratory of Science and Technology on Aero-Engine Beihang University Collaborative Innovation Center for Advanced Aero-Engine of China of Aerodynamics Beihang University

This paper experimentally investigates the effect of surface roughness on flow and heat transfer characteristics in circular microchannels. All test pieces include 44 identical, parallel circular microchannels with diameters of 0.4 mm and 10 mm in length. The surface roughness of the microchannels is R= 0.86, 0.92, 1.02 lm, and the Reynolds number ranges from 150 to *** show that the surface roughness of the circular microchannels has remarkable effects on the performance of flow behavior and heat transfer. It is found that the Poiseuille and Nusselt numbers are higher when the relative surface roughness is larger. For flow behavior, the friction factor increases consistently with the increasing Reynolds number, and it is larger than the constant theoretical value for macrochannels. The Reynolds number for the transition from laminar to turbulent flow is about 1500, which is lower than the value for macrochannels. For the heat transfer property, Nusselt number also increases with increasing Reynolds number, and larger roughness contributes to higher Nusselt number.

关键词： Circular Flow behavior Heat transfer Microchannels Roughness

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我国疟疾防治政策演变及趋势分析

中国卫生政策研究 2017年第3期10卷 70-74页

作者：咸越王曼丽邵天胡桃贺知菲刘春燕邵飘飘冯占春华中科技大学同济医学院医药卫生管理学院湖北武汉430030 湖北省人文社科重点研究基地-农村健康服务研究中心湖北武汉430030 国家卫生和计划生育委员会北京100044

建国以来,我国疟疾防治工作取得显著成效,目前已经基本建立较完备的疟疾防治政策体系。我国60多年疟疾防治工作主要分为四个阶段,政府针对各个阶段的疫情情况以及社会环境适时地制定和调整一系列防治疟疾的政策法规。本文回顾了我国疟... 详细信息

建国以来,我国疟疾防治工作取得显著成效,目前已经基本建立较完备的疟疾防治政策体系。我国60多年疟疾防治工作主要分为四个阶段,政府针对各个阶段的疫情情况以及社会环境适时地制定和调整一系列防治疟疾的政策法规。本文回顾了我国疟疾防治政策的历史演变,从各阶段疟疾疫情规模、主要政策内容及其特点等方面进行系统梳理归纳。在此基础上分析在政策指导下我国疟疾防治工作所取得的成绩以及在今后的防治工作中面临的挑战,从而提出制定和完善我国消除疟疾政策的若干建议,为我国实现消除疟疾的目标提供参考依据。

关键词：疟疾防治政策演变挑战建议

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang li-Shuo Zheng Yu-tao Zheng Yi-Wei Dong liping Huang Xiaoping Wang Wei Jiang liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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倾倒-滑移复合型倾倒变形体发育特征及渗流稳定性分析

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地质灾害与环境保护 2022年第4期33卷 33-40页

作者：江荣昊罗璟裴向军李天涛孙昊李骞地质灾害防治与地质环境保护国家重点实验室(成都理工大学) 成都610059

近年来,在山区工程建设和灾害防治中,以倾倒变形为主的岩质边坡稳定性问题越发突出,原岩在“倾倒-坠溃”作用下形成的巨块或碎石夹杂的坠覆堆积体,具有结构松散、透水性强的特点,在降雨条件下易整体滑移失稳。本文选取河北省平泉市南洞... 详细信息

近年来,在山区工程建设和灾害防治中,以倾倒变形为主的岩质边坡稳定性问题越发突出,原岩在“倾倒-坠溃”作用下形成的巨块或碎石夹杂的坠覆堆积体,具有结构松散、透水性强的特点,在降雨条件下易整体滑移失稳。本文选取河北省平泉市南洞子村倾倒变形体为研究对象,在详细调查其孕灾环境和宏观变形特征基础上,结合监测数据,探讨其变形破坏模式,并建立有限元分析模型,揭示不同重现期降雨强度下倾倒-滑移复合型倾倒变形体渗流场演化规律,分析降雨强度、历时对坡体稳定性的影响,初步确定其整体失稳的降雨阈值。结果表明:根据该变形体坡体结构和变形差异性,可将其划分为倾倒坠覆区、强烈倾倒区、轻微倾倒区和原岩区,其早期变形受控于坡体结构和上硬下软的岩性组合特征,变形破坏模式为压缩-弯曲-倾倒,而后期由于坡脚修路开挖和降雨的影响,变形破坏模式转变为蠕滑-拉裂-滑移;目前该变形体对降雨敏感度较高,降雨强度越大、历时越长,稳定性越差,并存在滞后效应;当降雨强度R≥176 mm/d(20 a一遇)时,坠覆体稳定性系数小于1,将发生整体失稳破坏。研究成果对此类变形体的安全预警及防治工作具有科学指导意义。

关键词：倾倒变形降雨变形破坏模式渗流稳定性数值模拟

Machine learning aided design of perovskite oxide materials for photocatalytic water splitting

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Journal of Energy Chemistry 2021年第9期30卷 351-359页

作者： Qiuling tao tian Lu Ye Sheng Long li Wencong Lu Minjie li Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China

Suffering from the inefficient traditional trial-and-error methods and the huge searching space filled by millions of candidates, discovering new perovskite visible photocatalysts with higher hydrogen production rate(RH_(2)) still remains a challenge in the field of photocatalytic water splitting(PWS). Herein, we established structural-property models targeted to RH_(2) and the proper bandgap(Eg) via machine learning(ML) technology to accelerate the discovery of efficient perovskite photocatalysts for PWS. The Pearson correlation coefficients(R) of leave-one-out cross validation(LOOCV) were adopted to compare the performances of different algorithms including gradient boosting regression(GBR), support vector regression(SVR), backpropagation artificial neural network(BPANN), and random forest(RF). It was found that the BPANN model showed the highest R values from LOOCV and testing data of 0.9897 and 0.9740 for RH_(2),while the GBR model had the best values of 0.9290 and 0.9207 for Eg. Furtherly, 14 potential PWS perovskite candidates were screened out from 30,000 ABO3-type perovskite structures under the criteria of structural stability, Eg, conduction band energy, valence band energy and RH_(2). The average RH_(2) of these14 perovskites is 6.4% higher than the highest value in the training data set. Moreover, the online web servers were developed to share our prediction models, which could be accessible in http://***/ocpmdm/material_api/ahfga3d9puqlknig(E_g prediction) and http://***/ocpmdm/material_api/i0 ucuyn3 wsd14940(RH_(2) prediction).

关键词： Perovskite Machine learning Online web service Photocatalytic water splitting Bandgap Hydrogen production rate

Promoting performance of lithium-sulfur battery via in situ sulfur reduced graphite oxide coating

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Rare Metals 2021年第2期40卷 417-424页

作者： Yuan li Xiao-tian Guo Song-tao Zhang Huan Pang Department of Pharmacy Jiangsu Food and Pharmaceutical Science CollegeHuai’an223003China School of Chemistry and Chemical Engineering Guangling CollegeYangzhou UniversityYangzhou225000China

Activated graphene/sulfur structure sheathed in a flexible graphene layer is presented as the cathode material of lithium-sulfur *** surface coating graphite oxide sheets are reduced by a one-step in situ sulfur reduction method under vacuum at 600℃without any additional *** high reduction degree of in situ sulfur reduced graphite oxide(RGO)coating layer will facilitate the rapid charge transfer at high current *** flexible encapsulated RGO structure will retard the diffusion of polysulfides and adjust the volume change of sulfur in *** a result,the electrochemical evaluation of the RGO-activated graphene(AG)/S electrode demonstrates superior capacity,cycling and rate *** RGO-AG/S electrode with 60 wt%sulfur loading achieves a stable cyclability over 2000 galvanostatic charge/discharge process(capacity-fade rate of only 0.03%per cycle at1600 mA·g^(-1)).The average Coulombic efficiency remains at~96%with no electrolyte additives(such as liNO_(3)).The outstanding property of RGO-AG/S electrode is attributed to the distinctive in situ sulfur RGOcoated hierarchical texture.

关键词： lithium-sulfur battery Surface coating In situ Activated graphene Long-term stability

Strong Current-State Opacity Verification of Discrete-Event Systems Modeled With Time Labeled Petri Nets

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 54-68页

作者： tao Qin li Yin Gaiyun liu Naiqi Wu Zhiwu li the Institute of Systems Engineering Macau University of Science and Technology IEEE the School of Electro-Mechanical Engineering Xidian University

This paper addresses the verification of strong currentstate opacity with respect to real-time observations generated from a discrete-event system that is modeled with time labeled Petri nets. The standard current-state opacity cannot completely characterize higher-level security. To ensure the higher-level security requirements of a time-dependent system, we propose a strong version of opacity known as strong current-state opacity. For any path(state-event sequence with time information)π derived from a real-time observation that ends at a secret state, the strong current-state opacity of the real-time observation signifies that there is a non-secret path with the same real-time observation as π. We propose general and non-secret state class graphs, which characterize the general and non-secret states of time-dependent systems, respectively. To capture the observable behavior of non-secret states, a non-secret observer is ***, we develop a structure called a real-time concurrent verifier to verify the strong current-state opacity of time labeled Petri nets. This approach is efficient since the real-time concurrent verifier can be constructed by solving a certain number of linear programming problems.

关键词：

A hybrid Wavelet-CNN-LSTM deep learning model for short-term urban water demand forecasting

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Frontiers of Environmental Science & Engineering 2023年第2期17卷 97-110页

作者： Zhengheng Pu Jieru Yan Lei Chen Zhirong li Wenchong tian tao tao Kunlun Xin College of Environmental Science and Engineering Tongji UniversityShanghai 200092China Smart Water Joint Innovation RD Center Tongji UniversityShanghai 200092China

Short-term water demand forecasting provides guidance on real-time water allocation in the water supply network, which help water utilities reduce energy cost and avoid potential accidents. Although a variety of methods have been proposed to improve forecast accuracy, it is still difficult for statistical models to learn the periodic patterns due to the chaotic nature of the water demand data with high temporal resolution. To overcome this issue from the perspective of improving data predictability, we proposed a hybrid Wavelet-CNN-LSTM model, that combines time-frequency decomposition characteristics of Wavelet Multi-Resolution Analysis (MRA) and implement it into an advanced deep learning model, CNN-LSTM. Four models - ANN, Conv1D, LSTM, GRUN - are used to compare with Wavelet-CNN-LSTM, and the results show that Wavelet-CNN-LSTM outperforms the other models both in single-step and multi-steps prediction. Besides, further mechanistic analysis revealed that MRA produce significant effect on improving model accuracy.

关键词： Short-term water demand forecasting Long-short term memory neural network Convolutional Neural Network Wavelet multi-resolution analysis Data-driven models

2001-2015年中国乙型病毒性肝炎流行特征研究的文献计量学分析

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医学动物防制 2018年第4期34卷 349-351,354页

作者：杨燕妮张丽田娟陶沁杨敬源贵州医科大学公共卫生学院贵阳550004 贵州省疾病预防控制中心

目的了解中国乙型病毒性肝炎(hepatitis B,HB)流行特征的研究现状及其发展趋势。方法采用文献计量学方法对2001-2015年"中国知网(CNKI)数据库"收录的有关中国乙型病毒性肝炎流行特征的相关研究文献进行定量统计分析。结果 2001-2015年... 详细信息

目的了解中国乙型病毒性肝炎(hepatitis B,HB)流行特征的研究现状及其发展趋势。方法采用文献计量学方法对2001-2015年"中国知网(CNKI)数据库"收录的有关中国乙型病毒性肝炎流行特征的相关研究文献进行定量统计分析。结果 2001-2015年共检索到乙型病毒性肝炎流行特征相关文献415篇,15年间国内刊物上该领域发表的文献数量呈逐年上升趋势,发文量排前3位的年份依次是2012年56篇、2015年54篇、2014年49篇。该研究领域拥有一支较广泛的作者队伍,主要科研力量集中在江苏、山东、浙江等7个省,发文量占发文总量的43.86%。收录文献较多的是《预防医学论坛》、《职业与健康》等10种期刊,占34.70%。93.19%的文献采用描述流行病学方法对乙型病毒性肝炎三间分布进行描述性分析并对防制策略进行探讨,有关乙型病毒性肝炎疫苗免疫策略实施以及规范监测效果评价的前瞻性及分析流行病学等方法的研究文献较为少见。结论乙型病毒性肝炎流行特征研究存在地区发展不平衡、研究机构局限、研究内容单一等情况,建议拓宽研究领域,加强机构间的合作,加大乙型病毒性肝炎规范监测体系、育龄妇女等重点人群乙型病毒性肝炎流行特征以及疫苗免疫策略效果评价方法学等方面的研究力度。

关键词：乙型病毒性肝炎流行特征文献计量学分析

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基于多学科诊疗模式的胰腺癌综合治疗

临床肝胆病杂志 2025年第12期40卷 2548-2552页

作者：马坦途李星霏李涛北京大学人民医院肝胆外科北京 100044

胰腺癌是消化道常见的恶性肿瘤之一，近年发病率逐步升高。其病理类型主要包括导管腺癌、小腺体癌、腺泡细胞癌等，其中导管腺癌是最常见的病理类型。多学科诊疗（MDT）是胰腺癌的新诊疗模式，通过集合不同的医疗团队，包括肝胆外科、... 详细信息

胰腺癌是消化道常见的恶性肿瘤之一，近年发病率逐步升高。其病理类型主要包括导管腺癌、小腺体癌、腺泡细胞癌等，其中导管腺癌是最常见的病理类型。多学科诊疗（MDT）是胰腺癌的新诊疗模式，通过集合不同的医疗团队，包括肝胆外科、消化内科、内分泌科、影像科和放疗科等，共同讨论患者的病情、制订治疗方案及后续管理，以确定最佳的个体化治疗方案。随着精准治疗的概念不断明确和发展、相关基因突变的发现，使得胰腺癌治疗前景更加广泛，个体化治疗更加深入，为改善患者治疗结果提供了机会。本文归纳了在MDT医疗模式下各学科之间的交互情况，并总结该模式下胰腺癌治疗方案的发展趋势和选择方向，指出了目前正在开展的工作及围绕未来胰腺癌MDT的研究方向。

关键词：胰腺肿瘤学科间信息交流诊断治疗学