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Hydration properties and thermal analysis of cement-based materials containing limestone powder

Journal of Central South University 2017年第12期24卷 2932-2939页

作者： ZHOU Wei LI Liang liu Shu-hua liu xing-hong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China School of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072 China School of Civil Engineering The University of Queensland Brisbane 4072 Australia School of Civil Engineering and Architecture Wuhan University Wuhan 430072 China

The hydration and thermal properties of cement-based materials containing various proportions of limestone powder as a partial replacement for ordinary Portland cement, were investigated and reported. Both compressive and flexural strengths of cement mortar with various contents of limestone powder were tested to study the influence of limestone powder on the strength development of resulting mixtures. The hydration heat and its rate of evolution were also tested, which clearly showed that the replacement percentage of limestone powder had significant effects on the total hydration heat but only a modest influence on the rate of heat evolution of cement-limestone binder. Importantly, the reduction coefficient of limestone powder on the hydration heat, needed for estimation of adiabatic temperature rise of cement-limestone binder, was found to be approximately 0.51. Fundamental thermal properties of these concrete mixtures containing limestone powder were also studied. Increasing the percentage of limestone powder resulted in a significant reduction in the adiabatic temperature rise but only a slight increase in other thermal properties such as thermal conductivity, thermal diffusivity and specific heat. In addition, thermal analysis using finite-element modelling indicated that inclusion of limestone powder did not significantly affect the rate of temperature rise nor the occurrence time of the highest temperature at early ages.

关键词： limestone powder cement mortar hydration properties thermal properties

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Facile Syntheses of 3-Isopentenyl Flavone and 3-Geranyl Flavone

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Chemical Research in Chinese Universities 2012年第6期28卷 994-998页

作者： HUANG Chu-sheng SHI Jian-cheng liu hong-xing CHEN Qian DUAN hong-xia College of Chemistry and Life Sciences Guangxi Teachers Education University Nanning 530001 1~ R. China" Department of Applied Chemistry College of Science China Agricultural University Beijing 100193 P. R. China

Although there was a strong steric effect,isopentenyl and geranyl moieties were successfully introduced into C3 position in flavone skeleton so as to synthesize the 3-isopentenyl flavone and 3-geranyl flavone under two cyclization conditions（AcOH/HCl and concentrated H 2 SO 4 /MeOH） in this *** was found that the optimum cyclization conditions for 3-isopentenyl flavone and 3-geranyl flavone were,respectively,AcOH/HCl and H 2 SO 4 /***,the donating electron ability is in the sequence 3-geranyl flavone3-isopentenyl flavone according to the density functional theory（DFT） calculations,suggesting the longer alkyl chain at 3-position would be more favorable for enhancing the donating electron *** present synthetic routes might reveal potential applicability in our continued studies on the total syntheses of other natural 3-alkyl flavonoids.

关键词： 3-Isopentenyl flavone 3-Geranyl flavone 3-Alkyl flavonoid

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The Improvement of ECG Parameter Estimation Obtained by Up-sampling 500 Hz Data

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Chinese Journal of Biomedical Engineering(English Edition) 2017年第1期26卷 38-46页

作者： YU Si-si liu hong-xing SUN xing-guo Nanjing University Fuwai Hospital

Nowadays, numerous commercial electrocardiographs(ECG) have500 Hz output sampling rate, i.e., 2 ms corresponding sampling interval. Medical workers who have no background of signal processing may worry about whether such low 500 Hz output sampling rate data could support high-precision estimation of electrocardiogram parameters by being up-sampled. With intention to clarify the problem to the medical workers, this paper takes some simulating experiment to illustrate *** experiment chose the RR interval and R peak amplitude as representative parameters to be estimated. The obtained results were as follows: for RR interval parameter,its estimation error can be lowered to below 0.3 ms by up-sampling; for R peak amplitude, its estimation error can be reduced to below 2.0 μV by up-sampling. It is believed that other ECG parameter estimation can also be improved similarly by up-sampling 500 Hz data.

关键词： electrocardiograph output data RR interval R peak amplitude estimation up-sampling

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Relationship between coronary atherosclerosis plaque characteristics and high sensitivity C-reactive proteins, interleukin-6

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Chinese Medical Journal 2011年第16期124卷 2452-2456页

作者： LAI Chun-lin JI You-rui liu Xiao-hong xing Jin-ping ZHAO Jian-qiang Department of Cardiology Shanxi Provincial People's HospitalTaiyuan Shanxi 030012 China

Background The relationship between inflammatory markers and the characteristics of coronary atherosclerosis plaques is uncertain. The aim of the present study was to evaluate the relationship between the characteristics of coronary atherosclerosis plaques and inflammatory markers such as high sensitivity C-reactive proteins （Hs-CRP） and interleukin-6 （IL-6）. Methods All patients suspected of having coronary heart disease （CHD） underwent Siemens 64-slice CT angiography （64-SCTA） to distinguish the quality of plaque of coronary artery lesions. Blood samples were taken to measure levels of serum Hs-CRP and IL-6 in different plaque groups and the control group and compared with the value of 64-SCTA for detection of coronary artery plaque. Results The sensitivity of detecting coronary artery plaque by 64-SCTA was 87.4%, the specificity was 87.1%, the positive predictive value was 82.2%, and the negative predictive value was 91.0%. Comparing the levels of serum Hs-CRP and IL-6 among plaque groups, the mean levels of serum Hs-CRP and IL-6 in three plaque groups were significantly higher than those in the control group （P 〈0.01）. The mean levels of serum Hs-CRP and IL-6 in the soft plaque group and mixed plaque group were significantly higher than those in hard plaque group （P〈0.01）. Plaque burden in the soft plaque group and mixed plaque group was significantly higher than in the hard plaque group （P 〈0.01）, but there was no statistical difference between the soft plaque group and mixed plaque group （P=-0.246）. There was a negative correlation between the CT scale and Hs-CRP and IL-6 levels in the soft plaque group （r= -0.621, P〈0.01, and r= -0.593, P 〈0.01 respectively）. There was a positive correlation between the plaque burden and Hs-CRP and IL-6 levels in the soft plaque group （r=0.579, P〈0.05 and r=0.429, P〈0.05 respectively）. Conclusions 64-SCTA is an effective way to distinguish the different quality of coronary atherosclerosis plaque. Serum Hs-CRP and IL-6 levels

关键词： coronary heart disease high sensitivity C-reactive protein interleukin-6 coronary atherosclerosis plaque

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High-precision Q modeling and Q migration technology and its applications in loess plateau regions

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Applied Geophysics 2024年第4期21卷 835-847,882页

作者： Xu Wei liu hong-xing Mi hong-Gang Zhang Bing Guo Jun-Chao Ge Yong You Jun China United Coalbed Methane Co. Ltd.Beijing 100015China Beijing Geotarget Research Co. Ltd.Beijing 101102China

The propagation of seismic waves in viscous media,such as the loess plateau and shallow gas regions,alters their amplitude,frequency,and phase due to absorption attenuation,resulting in reductions in the resolution and fi delity of seismic profi les and the inaccurate identifi cation of subtle structure and lithology.Q modeling and Q migration techniques proposed in this paper are used to compensate for the energy and frequency attenuation of seismic waves,obtain high-quality depth imaging results,and further enhance structural imaging to address the aforementioned ***,various prior information is utilized to construct an initial Q model.Q tomography techniques are employed to further optimize the precision of the initial Q model and build a high-precision Q ***,Q prestack depth migration technology is employed to compensate for absorption and attenuation in the three-dimensional space along the seismic wave propagation path and correct the travel times,realizing the purposes of amplitude compensation,frequency recovery,and phase correction,which can help improve the wave group characteristics while enhancing the *** data and practical application results demonstrate that high-precision Q modeling and Q migration techniques can substantially improve the imaging quality of underground structures and formations in the loess plateau region with extremely complex surface and near-surface *** resolution and fi delity of seismic data,as well as the capability to identify reservoirs,can be improved using these techniques.

关键词： absorption compensation Q modeling Q tomography inversion Q migration amplitude preserved loess plateau region

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Domain generalization with semi-supervised learning for people-centric activity recognition

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Science China(Information Sciences) 2025年第1期68卷 171-188页

作者： Jing liu Wei ZHU Di LI xing HU Liang SONG Academy for Engineering & Technology Fudan University Shanghai East-bund Research Institute on Networking Systems of AI School of Optoelectronic Information and Computer Engineering University of Shanghai for Science & Technology

People-centric activity recognition is one of the most critical technologies in a wide range of real-world applications,including intelligent transportation systems, healthcare services, and brain-computer interfaces. Large-scale data collection and annotation make the application of machine learning algorithms prohibitively expensive when adapting to new tasks. One way of circumventing this limitation is to train the model in a semi-supervised learning manner that utilizes a percentage of unlabeled data to reduce the labeling burden in prediction tasks. Despite their appeal, these models often assume that labeled and unlabeled data come from similar distributions, which leads to the domain shift problem caused by the presence of distribution gaps. To address these limitations, we propose herein a novel method for people-centric activity recognition,called domain generalization with semi-supervised learning(DGSSL), that effectively enhances the representation learning and domain alignment capabilities of a model. We first design a new autoregressive discriminator for adversarial training between unlabeled and labeled source domains, extracting domain-specific features to reduce the distribution gaps. Second, we introduce two reconstruction tasks to capture the task-specific features to avoid losing information related to representation learning while maintaining task-specific consistency. Finally, benefiting from the collaborative optimization of these two tasks, the model can accurately predict both the domain and category labels of the source domains for the classification task. We conduct extensive experiments on three real-world sensing datasets. The experimental results show that DGSSL surpasses the three state-of-the-art methods with better performance and generalization.

关键词： activity recognition deep learning domain generalization semi-supervised learning adversarial training

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导数平方和准则与SVM参数优化

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系统仿真学报 2008年第12期20卷 3150-3154,3159页

作者：肇莹刘红星高敦堂南京大学电了科学与工程系南京江苏210093

支持向量机(SVM)的性能与SVM参数的选择有关。SVM参数的优化需要一个准则。针对核函数选择RBF形式的情况,提出了一个新的SVM参数优化的准则,称作导数平方和准则。与著名的SVM参数优化方法如交叉验证或Radius/Margin Bound准则方法相比,... 详细信息

支持向量机(SVM)的性能与SVM参数的选择有关。SVM参数的优化需要一个准则。针对核函数选择RBF形式的情况,提出了一个新的SVM参数优化的准则,称作导数平方和准则。与著名的SVM参数优化方法如交叉验证或Radius/Margin Bound准则方法相比,利用提出的参数优化准则得到的分类面能够在原空间对样本集"平分秋色",体现了SVM分类器的结构风险最小化的原则,而且算法简单、计算量小、更易于实现。

关键词：准则参数优化支持向量机 RBF核函数

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前言:信息处理的智能化方法及应用

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南京大学学报（自然科学版） 2009年第4期45卷 439-441页

作者：刘红星南京大学电子科学与工程系南京210093

1947年、1950年英国的阿兰·图林(Turing)分别发表了"智能机器"、"计算机与智能"两文[1] ,提出了检验智能的一个标准:将问答双方互相隔开,问的一方为人,答的一方可以完全是计算机程序,也可以是人;如果提出的问题实际是由计算机程序来回... 详细信息

1947年、1950年英国的阿兰·图林(Turing)分别发表了"智能机器"、"计算机与智能"两文[1] ,提出了检验智能的一个标准:将问答双方互相隔开,问的一方为人,答的一方可以完全是计算机程序,也可以是人;如果提出的问题实际是由计算机程序来回答的,而在一定的范围内提问者又不能区分回答者是人还是机器,则可称这一机器是具有智能的.

关键词：智能化方法信息处理计算机程序应用智能机器

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