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喷油器弹簧鞍下杆凹陷引起柴油机机油稀释

内燃机车 2000年第2期 42-44页

作者：刘同锋王国建洛阳分局机务分处河南省洛阳市471000

就柴油机出现批量机油稀释进行了原因分析,为机务段排除类似故障提供了参考。

关键词：机油稀释喷油器内燃机车柴油机

Complexity and characteristic frequency studies in ECG signals of mice based on multiple scale factors

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Science China(Life Sciences) 2011年第6期54卷 544-552页

作者： YANG XiaoDong HE AiJun liu Peng SUN tongfeng NING XinBao School of Computer Science and Technology China University of Mining and TechnologyXuzhou 221116China School of Electronic Science and Engineering Institute for Biomedical Electronic EngineeringNanjing UniversityNanjing 210093China

Existing methods of physiological signal analysis based on nonlinear dynamic theories only examine the complexity difference of the signals under a single sampling *** developed a technique to measure the multifractal characteristic parameter intimately associated with physiological activities through a frequency scale *** parameter is highly sensitive to physiological and pathological *** received various drugs to imitate different physiological and pathological conditions,and the distributions of mass exponent spectrum curvature with scale factors from the electrocardiogram (ECG) signals of healthy and drug injected mice were ***,we determined the characteristic frequency scope in which the signal was of the highest complexity and most sensitive to impaired cardiac function,and examined the relationships between heart rate,heartbeat dynamic complexity,and sensitive frequency scope of the ECG *** found that all animals exhibited a scale factor range in which the absolute magnitudes of ECG mass exponent spectrum curvature achieve the maximum,and this range (or frequency scope) is not changed with calculated data points or maximal coarse-grained scale ***,the heart rate of mice was not necessarily associated with the nonlinear complexity of cardiac dynamics,but closely related to the most sensitive ECG frequency scope determined by characterization of this complex dynamic features for certain heartbeat ***,we found that the health status of the hearts of mice was directly related to the heartbeat dynamic complexity,both of which were positively correlated within the scale factor around the extremum region of the multifractal *** increasing heart rate,the sensitive frequency scope increased to a relatively high *** conclusion,these data provide important theoretical and practical data for the early diagnosis of cardiac disorders.

关键词： ECG multifractality complexity frequency scale factor characteristic frequency

激光雨滴谱仪与翻斗式雨量计降水量观测结果对比分析

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甘肃林业科技 2024年第3期49卷 73-78页

作者：王翠英仲怡铭仁增草陈徵尼宗文贞刘通峰凌雷甘肃兴隆山国家级自然保护区管护中心甘肃兰州730199 甘肃省林业科学研究院甘肃兰州730020 甘肃兴隆山森林生态系统国家定位观测研究站甘肃兰州730020 北京威瑞泰科技有限公司北京101100

为探究激光雨滴谱仪和翻斗式雨量计在降水量观测中的差异,本文利用兴隆山森林生态系统国家定位观测研究站林外标准气象场内激光雨滴谱仪与翻斗式雨量计观测的降水数据,对比分析了两种仪器在小、中、大三种降水强度下的降水量、月降水量... 详细信息

为探究激光雨滴谱仪和翻斗式雨量计在降水量观测中的差异,本文利用兴隆山森林生态系统国家定位观测研究站林外标准气象场内激光雨滴谱仪与翻斗式雨量计观测的降水数据,对比分析了两种仪器在小、中、大三种降水强度下的降水量、月降水量的差异以及差异产生的原因。结果表明:(1)两种仪器观测的累计降水量在小雨强度下差异最大,主要是由于降水强度很小时,雨滴小而雨速较缓,翻斗式雨量计达到了应翻转雨量才会翻动,反应滞后;(2)两种仪器观测的小时累计降水量相关关系随着雨强的增大而变大;(3)2023年5月—2024年5月,激光雨滴谱仪观测的降水量相对翻斗式雨量计的偏高,其中2023年5—9月差值较小,而2023年10月至次年2月差值较大,主要是由于激光雨滴谱仪能够识别雨夹雪、雪等小粒子。综上所述,激光雨滴谱仪和翻斗式雨量计各有优缺点,在实际应用中可根据具体需求和野外观测条件将两种仪器结合起来进行降水量观测。

关键词：激光雨滴谱仪翻斗式雨量计降水量月际变化

Smoking Is a Risk Factor of Colorectal Advanced Adenomas Compared to Nonadvanced Adenomas

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Open Journal of Gastroenterology 2022年第10期12卷 278-285页

作者： Siyong Chen Hailing liu tongfeng Zhao Department of Endocrinology The Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases The Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China Department of Pathology The Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China

Background: It is uncertain that whether smoking is a risk factor of colorectal advanced adenomas compared to nonadvanced adenomas, so we peformed the case-control study to explore this issue. Material and Methods: The cases were defined as patients with advanced adenomas and the controls were patients with nonadvanced adenomas. Clinical data were extracted from the hospital information system. Missing data were imputed with the multiple imputation of chained equations method, and the effect of smoking on the risk of advanced adenomas was calculated by binary logistic regression models to obtain odds ratios (ORs) and 95% confidence interval. Results: Current smoking rate in patients with advanced adenomas was significantly higher than that in patients with nonadvanced adenomas (31.6% VS 23.1%), the OR of advanced adenoma for current smoking compared with nonsmoking was 1.54 (1.09, 2.18), P = 0.013, and the weighted ORs ranged from 1.50 (1.01, 2.23) to 1.58 (1.09, 2.30), and the results of sensitivity analyses were still consistent. Conclusion: In adults with Han ethnicity in South China, current smoking is a risk factor of colorectal advanced adenomas compared to nonadvanced adenomas.

关键词： Smoking Colorectal Adenomas Advanced Adenomas

Should We Pay More Attention to Endotracheal Tube Fixation during Anesthesia—Surveys from Chinese Anesthesiologists for Endotracheal Tube Fixation and Endotracheal Tube Displacement in 2014 and 2020

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Open Journal of Anesthesiology 2021年第8期11卷 243-258页

作者： Dongxue Li tongfeng Luo Chuling liu Xi Hong Sanqing Jin Department of Anesthesia The Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China

Background: Displacement of endotracheal tube (ETT) can result in endobronchial intubation and accidental extubation that severely threatens safety of surgical patients. However, few surveys have investigated intraoperative ETT displacement experienced by anesthesiologists. The objective of these surveys was to investigate ETT fixation method and ETT displacement during general anesthesia experienced by anesthesiologists in China in 2014 and 2020. Methods: A questionnaire was designed with twenty questions and randomly distributed to anesthesiologists in two survey methods. In 2014, we collected responses from anesthesiologists who participated in the 22nd annual meeting of the Chinese Society of Anesthesiology in a face-to-face setting;in 2020, anesthesiologists from twenty-eight provinces completed the questionnaire through an online questionnaire survey platform. Differences in the responses from the anesthesiologists in 2014 and 2020 were assessed with a chi-square test. Results: In total, 568 questionnaires were collected, of which 541 questionnaires were valid (valid response rate 95.2%). A majority of the respondents (65.6%) had experienced ETT displacement, and 4.3% of respondents had experienced serious complications due to ETT displacement. Three hundred and twenty-nine respondents (60.8%) fixed the ETT with adhesive tape in the shape of the letter X. A majority of respondents considered the influence of surgical site, body position (97.8% of all respondents), and age (77.1% of all respondents) on fixing the ETT. Adhesive tape was the most commonly used material to fix the ETT (90.4% of the respondents). Conclusion: During clinical anesthesia, a majority of anesthesiologists experienced ETT displacement that can result in serious consequences. Therefore, the management of ETT should be a priority during the operation.

关键词： Anesthesia Endotracheal Tube Displacement Fixation Questionnaires

VTD-Net: Depth Face Forgery Oriented Video Tampering Detection based on Convolutional Neural Network

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VTD-Net: Depth Face Forgery Oriented Video Tampering Detecti...

铝酸盐水泥掺量对早强聚丙烯纤维砂浆性能影响研究

第三十九届中国控制会议

作者： tongfeng Yang Jian Wu Lihua liu Xu Chang Guorui Feng Shandong University of Political Science and Law

Face is the basis of identity authentication in many software, and the rise of generative adversary network makes the forgery of face easier than ever, which brings great challenges to information security. We propose a novel deep convolution neural network called VTD-Net to recognize faces generated by adversarial learning. The network is full-pipeline which composed of face location, interception, scaling and detection. In the experiment, we use the latest challenging face forgery dataset Celeb-DF, evaluated the forgery detection performance at frame level and video level, and achieved state-of-the-art results.

关键词： Image Forensics Generative Adversary Network Face Swap

来源： cnki会议评论

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施工技术 2014年第5期43卷 1-4页

作者：孙长征刘欢赵同峰沈阳建筑大学土木工程学院辽宁沈阳110168 沈阳建筑大学建筑设计研究院辽宁沈阳110015 辽宁省交通高等专科学校道路与桥梁工程系辽宁沈阳110122

通过向4种不同砂率的水泥砂浆中分别掺入3种不同百分比的铝酸盐水泥进行对比分析试验，找出最佳铝酸盐水泥掺量。在此基础上，为了进一步改善砂浆的力学性能，通过向早强砂浆中掺入6种不同体积掺量的聚丙烯纤维，进行对比分析试验，提... 详细信息

通过向4种不同砂率的水泥砂浆中分别掺入3种不同百分比的铝酸盐水泥进行对比分析试验，找出最佳铝酸盐水泥掺量。在此基础上，为了进一步改善砂浆的力学性能，通过向早强砂浆中掺入6种不同体积掺量的聚丙烯纤维，进行对比分析试验，提出聚丙烯纤维的最佳掺量。结果表明：当铝酸盐水泥掺量为5％时，聚丙烯纤维体积掺量在0．2％～0．4％时，基体3d抗折、抗压强度可分别达到12．1MPa和57．3MPa，且强度后期不倒缩，28d抗压强度可达到91．7MPa。该体系的SEM微观图貌显示，水泥水化充分，结构致密无裂纹。

关键词：砂浆早强砂率聚丙烯纤维

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方钢管钢骨混凝土轴压短柱极限承载力计算

辽宁工程技术大学学报（自然科学版） 2010年第2期29卷 220-223页

作者：赵同峰李宏男刘宏大连理工大学土木水利学院辽宁大连116024 沈阳建筑大学土木工程学院辽宁沈阳110004

为了进一步探讨方钢管钢骨混凝土轴心受压短柱极限承载力计算方法,在修正的方钢管钢骨混凝土混凝土本构模型基础上,采用有限元法建立了轴压短柱的计算模型,通过模型计算了载荷-轴向变形关系曲线,并与相关文献的试验曲线进行了对比,计算... 详细信息

为了进一步探讨方钢管钢骨混凝土轴心受压短柱极限承载力计算方法,在修正的方钢管钢骨混凝土混凝土本构模型基础上,采用有限元法建立了轴压短柱的计算模型,通过模型计算了载荷-轴向变形关系曲线,并与相关文献的试验曲线进行了对比,计算曲线与相关试验曲线吻合较好。通过对计算结果的回归分析,得出了实用的轴压承载力计算公式,利用该公式可进行方钢管钢骨混凝土轴压短柱的极限承载力进行预测。

关键词：方钢管混凝土轴压短柱有限元承载力计算公式

UV-H_2O_2法去除亚硝酸盐氮和氨氮的研究

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环境科学研究 1999年第1期12卷 15-16,26页

作者：何杰刘玉林谢同凤淮南工业学院化工系

用Ｈ２Ｏ２、紫外光（ＵＶ）辐射促进Ｈ２Ｏ２方法考察了水中ＮＯ－２和ＮＨ＋４的氧化，结果表明，ＮＯ－２能被Ｈ２Ｏ２有效地氧化，而ＮＨ＋４不能被ＮＯ－２和Ｈ２Ｏ２氧化，但ＵＶ辐射均有助于反应进行，使反应速率加快。

关键词：氧化硝酸盐氮氨氮化合物 UV辐射