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固硫灰渣中无水石膏分布规律研究

粉煤灰综合利用 2010年第4期24卷 3-4,8页

作者：徐惠忠宋远明王志娟烟台大学环境与材料工程学院山东烟台264005

流化床燃煤固硫灰渣(简称固硫灰渣)中的硫元素多以无水石膏形式存在。本文采用筛分和密度分离的方法,测定固硫灰渣中不同粒径及不同密度组分中的无水石膏含量。研究结果显示:固硫灰渣中的无水石膏易富集在粒径小、密度大的颗粒中。

关键词：固硫灰渣无水石膏分布粒径密度

急性颅脑损伤患者CT评分变化及血清乳酸、NSE、CRP的相关性分析

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临床神经外科杂志 2024年第2期21卷 198-201页

作者：黄海源许慧中颜庆华张猛刘枫东台市人民医院神经外科东台224200

目的探讨急性颅脑损伤(ACI)患者计算机断层扫描(CT)评分变化与血清乳酸(LA)、神经元特异性烯醇化酶(NSE)及C-反应蛋白(CRP)水平的关系及其对预后的预测价值。方法选取2020年1月—2022年1月东台市人民医院收治的50例急性颅脑损伤患者作... 详细信息

目的探讨急性颅脑损伤(ACI)患者计算机断层扫描(CT)评分变化与血清乳酸(LA)、神经元特异性烯醇化酶(NSE)及C-反应蛋白(CRP)水平的关系及其对预后的预测价值。方法选取2020年1月—2022年1月东台市人民医院收治的50例急性颅脑损伤患者作为疾病组,根据患者治疗后格拉斯哥预后评分(GOS)分为预后良好组(32例)和预后不良组(18例);选取50例行健康体检受试者作为健康组。受试者工作特征曲线(ROC)评估血清乳酸、NSE、CRP水平与CT评分对急性颅脑损伤患者预后的评估价值。结果疾病组血清乳酸、NSE、CRP水平均高于健康组(P<0.05);预后不良组乳酸、NSE、CRP水平和CT评分均高于预后良好组;经Spearman相关分析,急性颅内损伤患者血清中乳酸、NSE、CRP水平与CT评分呈正相关(r=0.431、r=0.345、r=0.226,均P<0.05);ROC曲线分析显示,血清乳酸、NSE、CRP水平、CT评分联合预测急性颅内感染预后的曲线下面积(AUC)高于单一指标检测(P<0.05)。结论急性颅脑损伤患者CT评分与患者入院血清乳酸、NSE、CRP水平呈正相关,联合诊断对患者预后评估有一定价值。

关键词：急性颅脑损伤 CT评分乳酸神经元特异性烯醇化酶 C-反应蛋白预后

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Feature Extraction and Recognition for Rolling Element Bearing Fault Utilizing Short-Time Fourier Transform and Non-negative Matrix Factorization

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 96-105页

作者： GAO huizhong LIANG Lin CHEN Xiaoguang xu Guanghua School of Mechanical Engineering Xi'an Jiaotong University The 705 Research Institute China Shipbuilding Industry Corporation Key Laboratory for Modern Design and Rotor-Bearing System of Education Ministry Xi'an Jiaotong University State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

Due to the non-stationary characteristics of vibration signals acquired from rolling element bearing fault, thc time-frequency analysis is often applied to describe the local information of these unstable signals smartly. However, it is difficult to classitythe high dimensional feature matrix directly because of too large dimensions for many classifiers. This paper combines the concepts of time-frequency distribution（TFD） with non-negative matrix factorization（NMF）, and proposes a novel TFD matrix factorization method to enhance representation and identification of bearing fault. Throughout this method, the TFD of a vibration signal is firstly accomplished to describe the localized faults with short-time Fourier transform（STFT）. Then, the supervised NMF mapping is adopted to extract the fault features from TFD. Meanwhile, the fault samples can be clustered and recognized automatically by using the clustering property of NMF. The proposed method takes advantages of the NMF in the parts-based representation and the adaptive clustering. The localized fault features of interest can be extracted as well. To evaluate the performance of the proposed method, the 9 kinds of the bearing fault on a test bench is performed. The proposed method can effectively identify the fault severity and different fault types. Moreover, in comparison with the artificial neural network（ANN）, NMF yields 99.3% mean accuracy which is much superior to ANN. This research presents a simple and practical resolution for the fault diagnosis problem of rolling element bearing in high dimensional feature space.

关键词： time-frequency distribution non-negative matrix factorization rolling element bearing feature extraction

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基于分子印迹的荧光传感技术及其应用研究

中国科学：化学 2020年第4期50卷 463-475页

作者：韩笑笑齐骥宋志花石雅君刘丰张昱韩京龙徐惠忠李博伟烟台大学环境与材料工程学院烟台264005 中国科学院烟台海岸带研究所海岸带环境过程与生态修复重点实验室山东省海岸带环境工程技术研究中心烟台264003 烟台大学药学院分子药理和药物评价教育部重点实验室新型制剂与生物技术药物研究山东省高校协同创新中心烟台264005

分子印迹技术(molecular imprinting technology, MIT)是针对某一特定模板分子制备具有特异选择性印迹聚合物(molecularly imprinted polymer, MIPs)的技术.以MIPs为分子识别元件,结合高度灵敏的荧光检测构建分子印迹荧光传感器(molecul... 详细信息

分子印迹技术(molecular imprinting technology, MIT)是针对某一特定模板分子制备具有特异选择性印迹聚合物(molecularly imprinted polymer, MIPs)的技术.以MIPs为分子识别元件,结合高度灵敏的荧光检测构建分子印迹荧光传感器(molecular imprinting-based fluorescence sensors, MI-FL sensors)在环境有机污染物的痕量检测领域备受关注.根据荧光发射信号的不同表达模式,本文介绍了多种不同分子印迹荧光传感器的构建策略和对环境中农药残留、雌激素、抗生素等有机污染物的检测应用,并展望了其面临的机遇与挑战.

关键词：分子印迹荧光传感器单发射型比率型农药残留雌激素抗生素

磺化石墨烯/多壁碳纳米管/二氧化锰复合材料的制备及其在超级电容器中的应用

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青岛科技大学学报（自然科学版） 2017年第3期38卷 66-70页

作者：赵杰许慧忠刘法谦李伟华中国科学院海洋研究所海洋环境腐蚀与生物污损重点实验室山东青岛266071 中国科学院大学北京100049 青岛科技大学高性能聚合物研究院山东青岛266042

通过冷冻干燥法制备了磺化石墨烯/多壁碳纳米管(简称碳纳米管)三维自支撑材料,并通过水热法成功在三维材料表面负载二氧化锰纳米颗粒。采用了具有良好导电性和水溶性的磺化石墨烯和碳纳米管作为二氧化锰的支撑基体,且所制备的材料呈现... 详细信息

通过冷冻干燥法制备了磺化石墨烯/多壁碳纳米管(简称碳纳米管)三维自支撑材料,并通过水热法成功在三维材料表面负载二氧化锰纳米颗粒。采用了具有良好导电性和水溶性的磺化石墨烯和碳纳米管作为二氧化锰的支撑基体,且所制备的材料呈现三维多孔结构,克服了传统二氧化锰材料导电性差等缺点。扫描电镜结果表明,石墨烯纳米片和碳纳米管相互支撑形成三维多孔结构;透射电镜结果表明,二氧化锰成功负载在石墨烯/碳纳米管材料之上;循环伏安测试表明,复合材料呈现良好的双电层电容特征;充放电测试结果表明,复合材料的具有优良的比电容。

关键词：磺化石墨烯碳纳米管二氧化锰超级电容器

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基于实时数据库的配电网开关站综合监测平台

上海电力学院学报 2015年第B5期31卷 43-45页

作者：孙富连阮远峰蔡金明徐惠中国网浙江德清县供电公司集体资产经营中心浙江德清313200

针对德清城区配电网开关站运行管理中无法实时在线监控的问题，提出并设计了基于PI实时数据库的配电网开关站综合监测平台，实现了对开关站环网设备运行及环境状态的管理及趋势分析，提高了开关站的安全运行水平．

关键词： PI实时数据库开关站综合监测

建设工程全过程项目管理中的BIM技术集成管理研究

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建筑施工 2019年第6期41卷 1174-1176页

作者：戴晶徐惠中马华明石盛玉杜杨上海市工程建设咨询监理有限公司上海200433 上海市浦东新区建设市场管理站上海200135

根据建设工程全过程项目管理的要求,梳理了建设工程项目管理和BIM技术应用的发展现状,并通过标准规范的查询对工程项目管理与BIM技术集成内容进行分析,最后以某工程全过程项目管理为例,介绍项目管理中BIM技术集成管理的框架搭建。

关键词：全过程项目管理 BIM技术集成管理框架管理方案

Ensemble Strategy for Insider Threat Detection from User Activity Logs

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Computers, Materials & Continua 2020年第11期65卷 1321-1334页

作者： Shihong Zou huizhong Sun Guosheng xu Ruijie Quan School of Cyberspace Security Beijing University of Posts and TelecommunicationBeijingChina Faculty of Engineering and Information Technology University of Technology SydneySydneyAustralia

In the information era,the core business and confidential information of enterprises/organizations is stored in information ***,certain malicious inside network users exist hidden inside the organization;these users intentionally or unintentionally misuse the privileges of the organization to obtain sensitive information from the *** existing approaches on insider threat detection mostly focus on monitoring,detecting,and preventing any malicious behavior generated by users within an organization’s system while ignoring the imbalanced ground-truth insider threat data impact on *** this end,to be able to detect insider threats more effectively,a data processing tool was developed to process the detected user activity to generate information-use events,and formulated a Data Adjustment(DA)strategy to adjust the weight of the minority and majority ***,an efficient ensemble strategy was utilized,which applied the extreme gradient boosting(XGBoost)model combined with the DA strategy to detect anomalous *** CERT dataset was used for an insider threat to evaluate our approach,which was a real-world dataset with artificially injected insider threat *** results demonstrated that the proposed approach can effectively detect insider threats,with an accuracy rate of 99.51%and an average recall rate of 98.16%.Compared with other classifiers,the detection performance is improved by 8.76%.

关键词： Insider threat data adjustment imbalanced data ensemble strategy

The age of the "old red sand" on the coasts of south Fujian and west Guangdong, China

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Chinese Science Bulletin 2000年第13期45卷 1216-1221页

作者： WU Zheng WANG Wei TAN huizhong xu Fengyu Department of Geography South China Normal UniversityGuangzhou 510631China Guangzhong Geography Institute Guangzhou 510070China City and Environment Department Xuzhou Normal UniversityXuzhou 221009China

The sedimentary strata and deposition ages of the 'old red sand' distributed along the coasts of south Fujian and west Guangdong are determined by lithostratigraphy, magnetic stratigraphy and earth chemistry combined with TL, ESR and 14C-dating techniques. The research shows that the 'old red sand' was aeolian sediments deposited from 55 400 to 9 000 aBP, the last glacial period in the middle and later age of Late Pleistocene. Most of them deposited in two periods of 56-42 ka and 30-10 ka. The 'old red sand' deposited in the period of 30-10 ka, the later Wurm glacier substage (Q33), developed on the largest scale with the widest distribution.

关键词： “old red sand” classification of sedimentary strata age of deposition coasts of south Fujian and west Guangdong.