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细观结构不均匀性对混凝土动弯拉强度的影响

水利学报 2005年第7期36卷 846-852页

作者：马怀发陈厚群黎保琨北京工业大学北京100044 中国水利水电科学研究院工程抗震研究中心北京100044

本文在随机骨料模型的基础上,提出了既能反映混凝土骨料分布随机性又能反映混凝土细观各相材料力学特性随机性的随机骨料随机参数模型。利用该模型并考虑材料的细观力学的应变率效应,对湿筛混凝土和全级配混凝土梁进行了三分点冲击弯拉... 详细信息

本文在随机骨料模型的基础上,提出了既能反映混凝土骨料分布随机性又能反映混凝土细观各相材料力学特性随机性的随机骨料随机参数模型。利用该模型并考虑材料的细观力学的应变率效应,对湿筛混凝土和全级配混凝土梁进行了三分点冲击弯拉断裂数值模拟,分析了混凝土材料参数的离散性、混凝土级配以及初始静预载水平对其动弯拉强度的影响。研究表明:(1)随混凝土材料的弹性模量和抗拉强度的离散性增大,静弯拉强度和动弯拉强度降低,但动弯拉强度增强系数得到提高;(2)一定条件下全级配的混凝土梁的动弯拉强度增强系数高于湿筛混凝土梁的动弯拉强度增强系数;(3)为了更准确地确定动弯拉强度增强系数,应该考虑混凝土级配和初始预静载水平所产生的应变率效应对其的影响。

关键词：细观力学混凝土应变率效应动弯拉强度不均匀性随机骨料随机参数模型

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塔里木河下游地区地下水空间分布动态模拟

资源科学 2006年第5期28卷 95-101页

作者：刘英包安明陈曦中国科学院新疆生态与地理研究所

塔里木河是典型的内陆河,其两岸植被主要依靠地下水维持生长,两岸的地下水埋深对以胡杨、柽柳为建群种的植被群落起着关键性作用。本文根据塔里木河下游区域地下水主要是河道补给等水文地质特征,以数字高程模型(DEM)为基础数据,利用有... 详细信息

塔里木河是典型的内陆河,其两岸植被主要依靠地下水维持生长,两岸的地下水埋深对以胡杨、柽柳为建群种的植被群落起着关键性作用。本文根据塔里木河下游区域地下水主要是河道补给等水文地质特征,以数字高程模型(DEM)为基础数据,利用有限元三角剖分Feflow时间滞后的一维线性插值方法处理河流数据,综合应用地理信息系统ArcGIS和Feflow进行地下水的空间分布模拟。本方法克服了地下水观测点很少、基础资料缺乏的缺陷,从面上直观再现了塔里木河下游典型断面阿拉干断面的地下水变化情况,动态再现地下水水位,生成地下水埋深,为分析地下水与植被关系提供了借鉴。

关键词： GIS FEFLOW DEM 地下水塔里木河下游

Chronic social stress impairs prefrontal cortical myelination in the juvenile mice

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Chronic social stress impairs prefrontal cortical myelinatio...

电石渣/偏高岭土固化铜污染土的浸泡试验研究

中国神经科学学会第十二届全国学术会议

作者： Qiu-Hui-Hong YU Xing-chen CAO Jing WANG bao-Ming LI Laboratory of Cognitive Functions and Disorders Nanchang University School of Life Science Nanchang University

Objective Chronic social stress induces permanent phenotypic changes, and impairs the cognitive functions associated with the prefrontal cortex（PFC）, a brain region particularly vulnerable to stress effects. However, the underlying mechanism remains unclear. In this work, we used chronic social defeat（CSD） model to illuminate whether CSD affects myelination of PFC, and what the underlying cellular and molecular mechanism is. Methods The male C57 BL/6 mice（Postnatal 21 days） were subjected to repeated social defeat for 10 consecutive days. We used immunohistochemistry to examine the distribution of myelin within the mice PFC over the lifespan, to investigated myelination and the number of oligodendroglial lineage cells in the PFC after CSD. Results（1） We found that P10 to P30 is a critical period of myelination in the PFC.（2） We showed that CSD reduced the myelin basic protein（MBP） staining area in the PFC, but not affected the MBP level of the motor cortex, corpus callosum, striatum and hippocampus.（3） We observed a significant decreased number of myelinating oligodendrocytes（CC1+/OLIG2+ cells） and increased number of oligodendrocyte precursor cell（PDGRFα+ cells） in the CSD group compared with CON group. Conclusion These results indicate that chronic social stress impairs myelination and oligodendrogenesis of the prefrontal cortex, which may be a potential target for researching PFC-depended cognitive function deficit.

关键词： chronic social stress juvenile mice prefrontal cortex myelination oligodendrocytes

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中南大学学报（自然科学版） 2018年第3期49卷 678-683页

作者：陈永贵潘侃谭邦宏叶为民陈宝同济大学岩土及地下工程教育部重点实验室上海200092 广西交通投资集团南宁高速公路运营有限公司广西南宁530022

针对电石渣/偏高岭土地聚合物固化铜污染土开展去离子水和盐酸条件下的浸泡试验,研究固化污染土无侧限抗压强度变化规律,分析浸泡条件对固化污染土稳定性的影响。研究结果表明:在未浸泡条件下,固化污染土无侧限抗压强度随着电石渣掺量... 详细信息

针对电石渣/偏高岭土地聚合物固化铜污染土开展去离子水和盐酸条件下的浸泡试验,研究固化污染土无侧限抗压强度变化规律,分析浸泡条件对固化污染土稳定性的影响。研究结果表明:在未浸泡条件下,固化污染土无侧限抗压强度随着电石渣掺量的增加而增大;当电石渣掺量较低时,固化污染土的应力随应变增加而缓慢增大,无明显峰值;当电石渣质量分数超过9%时,应力随应变增加而较快增大,强度峰值明显;在去离子水和盐酸浸泡条件下,固化污染土的无侧限抗压强度变化趋势基本一致,随着电石渣掺量增加而增大,且明显低于未浸泡固化污染土的无侧限抗压强度;当电石渣质量分数为10%,偏高岭土质量分数为5%时,电石渣/偏高岭土地聚合物对铜污染土具有较强的抗酸稳定性,修复效果良好。

关键词：铜污染土固化/稳定化电石渣浸泡试验

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融合解析模型和综合模型的压缩感知算法

电子学报 2016年第3期44卷 613-619页

作者：练秋生韩敏石保顺陈书贞燕山大学信息科学与工程学院河北秦皇岛066004

如何利用更多的图像先验知识来提高图像的重构质量是压缩感知的一个关键问题.本文将综合稀疏模型与近几年提出的Cosparse解析模型结合,利用图像在综合字典和解析字典下的稀疏性提出了一种融合两种稀疏先验的图像重构算法,并利用交替方... 详细信息

如何利用更多的图像先验知识来提高图像的重构质量是压缩感知的一个关键问题.本文将综合稀疏模型与近几年提出的Cosparse解析模型结合,利用图像在综合字典和解析字典下的稀疏性提出了一种融合两种稀疏先验的图像重构算法,并利用交替方向乘子法(ADMM)求解对应的复杂优化问题.为进一步提高算法性能,该算法还充分利用了图像中任意位置图像块的稀疏性.实验结果表明,本文算法能有效提高图像重构质量.

关键词：压缩感知稀疏表示 Cosparse解析模型图像重构

Efficacy of Acitretin Monotherapy on Basal Cell Carcinoma:A Case Report

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International Journal of Dermatology and Venereology 2022年第3期5卷 172-174页

作者： Ping-Jiao chen Jing-Yao Liang Xin Tian Chang-Xing Li Xi-bao Zhang Department of Dermatology of Southern Hospital Southern Medical UniversityGuangzhouGuangdong 510515China Institute of Dermatology Guangzhou Medical UniversityGuangzhouGuangdong 510095China Department of Dermatology Guangzhou Institute of DermatologyGuangzhouGuangdong 510095China

Introduction:Basal cell carcinoma(BCC)is the most common skin cancer which mainly affects the population over 50 years of *** addition to surgical treatment,nonsurgical treatment is also an attractive option for some *** herein report a case of an 82-year-old man with BCC successfully treated with *** presentation:An 82-year-old man presented with BCC on his left nose wing more than 2 years *** to his unwillingness to accept treatment that may lead to pain,discomfort,or trauma,the patient was prescribed oral acitretin 25 mg twice daily[0.8 mg/(kg·d)]and was instructed to apply 2%fusidic acid cream topically once daily for trauma *** lesion progressively shrank in size after 4 weeks of treatment,and was almost completely resolved after 28 weeks of *** patient reported mild adverse effects,such as mild skin fragility and cheilitis,and apparent scaling skin,which caused minor discomfort but did not affect the continuation of ***:The pathogenesis of BCC is still unclear,but it has been demonstrated to be linked to overactive hedgehog signaling and its crosstalk with other pathways such as phosphoinositide 3-kinase and mammalian target of *** could obviously inhibit cell growth and proliferation and down-regulate AMP-dependent protein kinases that plays critical role in the blocking of malignant progression of several tumors including ***:We provide an effective alternative for the patients with BCC who are unwilling to receive surgical therapy.

关键词： acitretin monotherapy basal cell carcinoma

Protection of lung function by introducing single photon emission computed tomography lung perfusion image into radiotherapy plan of lung cancer

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Chinese Medical Journal 2009年第5期122卷 509-513页

作者： YIN Yong chen Jin-hu LI bao-sheng LIU Tong-hai LU jie BAI Tong DONG Xiao-ling YU Jin-ming Department of Biomedical Engineering Tianjin University Tianjin 300070 China Department of Radiation Oncology Shandong Tumor Hospital and Institute Jinan Shandong 250117 China

Background The lung functional status could be displayed on lung perfusion images. With the images, the radiotherapy plans of lung cancer could be guided to more optimized. This study aimed to assess quantitatively the impact of incorporating functional lung imaging into 3-dimensional conformal radiotherapy （3DCRT） and intensity-modulated radiation therapy （IMRT） planning for non-small cell lung cancer （NSCLC）. Methods Ten patients with NSCLC who had undergone radiotherapy were included in this study. Before radiotherapy, each patient underwent CT simulation and lung perfusion imaging with single photon emission computed tomography （SPECT）. The SPECT images were registered with simulation planning CT and used to contour functional lung （lung-F） and non-functional lung （lung-NF）. Two 3DCRT plans and two IMRT plans were designed and compared in each patient： two anatomic plans using simulation CT alone and two functional plans using SPECT-CT in addition to the simulation CT. Dosimetric parameters of the four types of plans were compared in terms of tumor coverage and avoidance of normal tissues. Total radiation dose was set at 66 Gy （2 Gyx33 fractions）. Results In incorporating perfusion information in 3DCRT and IMRT planning, the reductions on average in the mean doses to the functional lung in the functional plan were 168 cGy and 89 cGy, respectively, compared with those in the anatomic plans. The median reductions in the percentage of volume irradiated with 〉5 Gy, 〉10 Gy, 〉20 Gy, 〉30 Gy and 〉40 Gy for functional lung in the functional plans were 6.50%, 10.21%, 14.02%, 22.30% and 23.46% in 3DCRT planning, respectively, and 3.05%, 15.52%, 14.16%, 4.87%, and 3.33% in IMRT planning, respectively. No greater degree of sparing of the functional lung was achieved in functional IMRT than in 3DCRT. Conclusion Function-guided 3DCRT and IMRT plannings both appear to be effective in preserving functional lung in NSCLC patients.

关键词： lung cancer radiotherapy lung perfusion lung function

基于高阶马尔可夫随机场及非线性压缩感知的相位恢复算法

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电子学报 2017年第9期45卷 2210-2217页

作者：练秋生宋爽陈书贞石保顺燕山大学信息科学与工程学院河北秦皇岛066004

在编码衍射成像系统中,为精确重构复图像的幅值和相位,需获取大量的编码衍射图样,导致数据采集时间长.为减少编码衍射图样的数量,本文基于非线性压缩感知理论框架,利用高阶马尔可夫随机场统计先验模型,提出了一种鲁棒相位恢复算法.该方... 详细信息

在编码衍射成像系统中,为精确重构复图像的幅值和相位,需获取大量的编码衍射图样,导致数据采集时间长.为减少编码衍射图样的数量,本文基于非线性压缩感知理论框架,利用高阶马尔可夫随机场统计先验模型,提出了一种鲁棒相位恢复算法.该方法将复图像的幅值和相位分别进行正则化,并将数据保真项与幅值和相位正则项结合作为代价函数,采用Heavy-Ball算法求解所对应的非凸优化问题.实验结果表明,本文算法在编码衍射图样较少的情况下仍能获得较高的图像重构质量,且对噪声鲁棒.

关键词：非线性压缩感知相位恢复高阶马尔可夫随机场编码衍射图样

基于BIRCH-LKD的在站车辆中时异常检测算法

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北京理工大学学报 2017年第11期37卷 1122-1128页

作者：张晓栋董宝田陈光伟北京交通大学交通运输学院北京100044 中国铁路总公司中国铁路总公司信息技术中心北京100860

针对铁路车辆在站中转作业异常较多的情况,提出基于BIRCH-LKD的在站车辆中时异常检测算法.该算法以车辆中时序列为研究对象,不考虑异常值的具体形式,对序列分组,引入中时序列特征向量,做类球形簇转化;采用基于划分的显性异常检测方法得... 详细信息

针对铁路车辆在站中转作业异常较多的情况,提出基于BIRCH-LKD的在站车辆中时异常检测算法.该算法以车辆中时序列为研究对象,不考虑异常值的具体形式,对序列分组,引入中时序列特征向量,做类球形簇转化;采用基于划分的显性异常检测方法得到中时序列特征向量的聚类特征树,查找序列显性异常,缩小异常检测范围;利用隐性异常检测算法计算剩余数据对象的K距离,根据距离差值变化规律,筛选序列隐性异常;最后,利用中时序列中位数异常判定条件,排除下界异常,实现中时序列的异常检测.实验结果表明,该算法检出率高,能够快速识别中时序列异常值,有效率达85%以上,去除异常值后的中时序列符合实际情况的趋势且更加平稳.

关键词：车辆中时异常检测 BIRCH聚类算法 K距离时间序列