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合成氨变换工序的Ω-H图法分析 被引量:4
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作者 王彦峰 冯霄 《化工进展》 EI CAS CSCD 2000年第1期63-66,70,共5页
简要介绍了Ω-H图法,并给出了化学反应过程在该图上的表示,用此方法对合成氨的变换工序进行了分析,对原流程进行了改进。结果表明,Ω-H图法是分析化工过程的有力工具。
关键词 夹点分析 化工过程 合成氮 变换工序 图法分析
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基于谓词执行信息分析的自适应缺陷定位算法 被引量:7
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作者 郝鹏 郑征 +3 位作者 张震宇 高乙超 宫成 薛云志 《计算机学报》 EI CSCD 北大核心 2014年第3期500-511,共12页
查找程序中缺陷代码所在的位置是一项值得深入开展的研究,同时也是实际软件调试过程中所面临的一个难题,这一过程往往需要耗费大量的时间和人力资源.研究软件缺陷定位的一类重要方法是基于谓词的统计学缺陷定位方法(简称PBSFL).PBSFL通... 查找程序中缺陷代码所在的位置是一项值得深入开展的研究,同时也是实际软件调试过程中所面临的一个难题,这一过程往往需要耗费大量的时间和人力资源.研究软件缺陷定位的一类重要方法是基于谓词的统计学缺陷定位方法(简称PBSFL).PBSFL通过比较程序运行成功与失败时谓词的执行信息差异来获得谓词与缺陷的关联程度.然而实验研究发现,固定算法中信息利用的强度会造成信息利用不足或过分利用现象的发生,导致现有PBSFL方法对某些缺陷定位不够准确.针对这一问题,文中设计了一种基于谓词执行信息分析的自适应缺陷定位算法,该算法通过分析测试用例运行时谓词的执行情况来动态地为每个谓词选择合适的信息利用强度.实验结果表明,该方法在Siemens和space两个程序包上表现出很好的定位效果以及定位稳定性. 展开更多
关键词 统计学缺陷定位 谓词执行信息 自适应 软件测试 程序分析图法
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油井远程在线计量优化分析系统技术在大港油田的应用 被引量:16
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作者 檀朝东 史明义 +2 位作者 易南华 关成尧 余金泽 《中国石油和化工》 2007年第20期43-48,共6页
在油井无计量站情况下,采用油井集群单井远程计量自动监测系统,并与专门的油水井计量分析软件结合,形成了油井远程监控、液量自动计量及分析优化系统,实现单井远程自动计量需要。本文简要说明该系统技术的原理与功能,重点论述该技术在... 在油井无计量站情况下,采用油井集群单井远程计量自动监测系统,并与专门的油水井计量分析软件结合,形成了油井远程监控、液量自动计量及分析优化系统,实现单井远程自动计量需要。本文简要说明该系统技术的原理与功能,重点论述该技术在整个大港油田对不同类型油井的应用效果。该系统已在大港油田先导性试验成功并推广应用,能替代或简化计量流程,降低产能建设投入和运行成本。 展开更多
关键词 油井在线计量地面简化功图法量液分析优化应用
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Context-attributed graph grammar framework for specifying visual languages
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作者 邹阳 曾晓勤 +1 位作者 韩秀清 张康 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期455-461,共7页
Since the specifications of most of the existing context-sensitive graph grammars tend to be either too intricate or not intuitive, a novel context-sensitive graph grammar formalism, called context-attributed graph gr... Since the specifications of most of the existing context-sensitive graph grammars tend to be either too intricate or not intuitive, a novel context-sensitive graph grammar formalism, called context-attributed graph grammar(CAGG), is proposed. In order to resolve the embedding problem, context information of a graph production in the CAGG is represented in the form of context attributes of the nodes involved. Moreover, several properties of a set of confluent CAGG productions are characterized, and then an algorithm based on them is developed to decide whether or not a set of productions is confluent, which provides the foundation for the design of efficient parsing algorithms. It can also be shown through the comparison of CAGG with several typical context-sensitive graph grammars that CAGG is more succinct and, at the same time, more intuitive than the others, making it more suitably and effortlessly applicable to the specification of visual languages. 展开更多
关键词 visual language graph grammar context-attributed PARSING CONFLUENCE
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索马里流系区域海温的年际变化 被引量:1
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作者 赵芳 胡瑞金 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第3期17-25,共9页
利用SODA资料对索马里流系区域海表温度(SST)的年际变化及其影响原因进行了研究。结果表明,春、秋季和冬季的索马里流系区SST呈现全区一致型的变化,但是夏季除了有全区一致型的变化外,还存在南北反位相的变化。夏季海温的这2种变化类型... 利用SODA资料对索马里流系区域海表温度(SST)的年际变化及其影响原因进行了研究。结果表明,春、秋季和冬季的索马里流系区SST呈现全区一致型的变化,但是夏季除了有全区一致型的变化外,还存在南北反位相的变化。夏季海温的这2种变化类型与ENSO、印度洋偶极子及印度季风存在密切关系。通过合成分析发现,在夏季全区一致型时,6月份热带西南印度洋、索马里沿岸的风应力旋度和大小与阿拉伯海均呈现相反的变化特点,夏季索马里流系区域海温变化主要受上升流和蒸发共同影响;在南北反位相型时,5月份的风应力变化信号最明显,且显著区域的位置和大小与全区一致型时的6月份不完全对应;夏季索马里流系南区SST异常可以利用上升流和蒸发异常进行解释,但北区的SST异常并非如此,其它因素应该起主导作用。 展开更多
关键词 海表温度(SST) 索马里流系 年际变化 SODA 合成分析图法
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平行双目视觉系统的定位误差补偿 被引量:5
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作者 樊海风 王见 《计算技术与自动化》 2019年第2期135-140,共6页
测量精度在平行双目视觉系统的应用中非常重要.为了提高测量系统的精度,提出了基于改进的BP神经网络的误差补偿策略。采用不同位置处的测量数据作为学习样本,利用训练好的网络模型预测测量系统的误差,对测量结果进行误差补偿,得到新的... 测量精度在平行双目视觉系统的应用中非常重要.为了提高测量系统的精度,提出了基于改进的BP神经网络的误差补偿策略。采用不同位置处的测量数据作为学习样本,利用训练好的网络模型预测测量系统的误差,对测量结果进行误差补偿,得到新的数据作为测量值。实验结果表明,该方法的结果值相较原始数据,误差减少了70%,为提高视觉系统的定位精度提供了一种新的思路。 展开更多
关键词 双目视觉 误差补偿 BP神经网络 预测 误差分析图法分类号:TP391文献标识码A
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Responses of some landscape trees to the drought and high temperature events during 2006 and 2007 in Yamaguchi, Japan 被引量:3
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作者 WANG Fei Haruhiko Yamamoto Yasuomi Ibaraki 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第3期254-260,共7页
Extreme weather events were analyzed based on the meteorological data from the year of 1967 to 2007 for Yamaguchi, Japan. The responses from landscape trees were also investigated mainly by the analysis of image pixel... Extreme weather events were analyzed based on the meteorological data from the year of 1967 to 2007 for Yamaguchi, Japan. The responses from landscape trees were also investigated mainly by the analysis of image pixel and spectral reflectance, Results show that after the dry, hot and windy summer in 2007, many landscape trees in Yamaguchi City tended to respond the extreme weather events by re- ducing their leaf surface area and receiving less radiation energy. Premature leaf discoloration or defoliation appeared on some landscape tree species and leaf necrosis occurred on tip and margin of many Kousa dogwood (Comus kousa) trees at unfavorable sites. Described by image pixel analysis method, the leaf necrotic area percentage (LNAP) of sampled dogwood trees averaged 41.6% and the sampled Sasanqua camellia (Camelia sasanqua) tree also showed fewer flowers in flower season of 2007 than that in 2006. By differential analysis of partial discolored crown, it presented a logistic differential equation of crown color for sweet gum (Liquidambar styraciflua) trees. It suggested that the persistent higher temperature and lower precipitation could be injurious to the sensitive landscape trees at poor sites, even in relative humid area like Yamaguchi. 展开更多
关键词 extreme meteorological event drought and high temperature landscape tree image pixel analysis response
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An insulinoma with clinical and electroencephalographic features resembling complex partial seizures 被引量:3
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作者 Shuang WANG Hai-tao HU Shu-qun WEN Zhong-jin WANG Bao-rong ZHANG Mei-ping DING 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第6期496-499,共4页
We described a female patient with insulinoma who experienced recurrent episodes of automatism, confusion and convulsion. Furthermore, her electroencephalography (EEG) findings resembled the pattern in complex parti... We described a female patient with insulinoma who experienced recurrent episodes of automatism, confusion and convulsion. Furthermore, her electroencephalography (EEG) findings resembled the pattern in complex partial seizures with secondary generalization. The interictal EEG showed spikes and sharp waves, as well as focal slowing over the left temporal lobe, and the ictal EEG revealed generalized spikes and sharp waves associated with diffused slowing. She was initially misdiagnosed as pharmacoresistant epilepsy. After the insulinoma was found and surgically removed, her EEG turned normal and she was seizure-free during the 4-year follow-up. This report highlights the need for careful reassessment of all seizures refractory to medication, even for the oatients associated with eoileotiform discharges on EEG. 展开更多
关键词 INSULINOMA HYPOGLYCEMIA Electroencephalography (EEG) SEIZURE
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Chromatographic fingerprint analysis of Fructus Aurantii Immaturus by HPLC-DAD and chemometric methods 被引量:4
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作者 徐小娜 蒋军辉 +3 位作者 梁逸曾 李晓如 易伦朝 成金乐 《Journal of Central South University》 SCIE EI CAS 2011年第2期353-360,共8页
An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array de... An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array detector (HPLC-DAD) procedure coupled with chemometric methods was developed for fingerprint analysis,qualitative analysis and quantitative determination of this herb. In qualitative and quantitative analyses,heuristic evolving latent projection (HELP) method was employed to resolve the overlapping peaks of the tested samples. Two bioactive components,namely hesperidin and naringin,are confirmed and determined,together with four flavonoids compounds tentatively identified including two new ones. From fingerprint analysis,the fingerprint data were processed with correlation coefficients for quantitative expression of their similarity and dissimilarity. The developed method based on an integration of chromatographic fingerprint and quantitative analysis is scientific,and the obtained results can be applied to the quality control of herb medicine. 展开更多
关键词 FINGERPRINT quality control Fructus Aurantii Immaturus high-performance liquid chromatography heuristic evolvinglatent projection method HESPERIDIN NARINGIN
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ECT Image Analysis Methods for Shear Zone Measurements during Silo Discharging Process 被引量:1
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作者 Krzysztof Grudzien Zbigniew Chaniecki +2 位作者 Andrzej Romanowski Maciej Niedostatkiewicz Dominik Sankowski 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期337-345,共9页
The paper covers the electrical capacitance tomography(ECT) data analysis on shear zones formed during silo discharging process.This is due to the ECT aptitude for detection of slight changes of material concentration... The paper covers the electrical capacitance tomography(ECT) data analysis on shear zones formed during silo discharging process.This is due to the ECT aptitude for detection of slight changes of material concentration.On the basis of ECT visualisations,wall-adjacent shear zone profiles are analysed for different wall roughness parameters.The analysis on changes of material concentration,based on ECT images,enables the calculation for the characteristic parameters of shear zones-size and material concentration inside the shear zone in a dynamic process of silo discharging.In order to verify the methodology a series of experiments on gravitational flow of bulk solids under various conditions were conducted with different initial granular material packing densities and silo wall roughness.The investigation shows that the increase in container wall roughness is an effective method for reducing the dynamic effects during the material discharging,since these effects are resulted from the resonance between hopper construction and trembling material.Such effects will damage industrial equipment in practical applications and need further investigation. 展开更多
关键词 electrical capacitance tomography silo flow shear zone
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A Closed Form Solution to Segment 3D Motion Using Straight-line Optical Flow 被引量:2
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作者 张婧 石繁槐 +1 位作者 马文娟 刘允才 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期76-80,共5页
A closed form solution to the problem of segmenting multiple 3D motion models was proposed from straight-line optical flow. It introduced the multibody line optical flow constraint (MLOFC), a polynomial equation relat... A closed form solution to the problem of segmenting multiple 3D motion models was proposed from straight-line optical flow. It introduced the multibody line optical flow constraint (MLOFC), a polynomial equation relating motion models and line parameters. The motion models can be obtained analytically as the derivative of the MLOFC at the corresponding line measurement, without knowing the motion model associated with that line. Experiments on real and synthetic sequences were also presented. 展开更多
关键词 SEGMENTATION optical flow LINE generalized principal component analysis (GPCA)
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MR-CLOPE: A Map Reduce based transactional clustering algorithm for DNS query log analysis 被引量:2
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作者 李晔锋 乐嘉锦 +2 位作者 王梅 张滨 刘良旭 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3485-3494,共10页
DNS(domain name system) query log analysis has been a popular research topic in recent years. CLOPE, the represented transactional clustering algorithm, could be readily used for DNS query log mining. However, the alg... DNS(domain name system) query log analysis has been a popular research topic in recent years. CLOPE, the represented transactional clustering algorithm, could be readily used for DNS query log mining. However, the algorithm is inefficient when processing large scale data. The MR-CLOPE algorithm is proposed, which is an extension and improvement on CLOPE based on Map Reduce. Different from the previous parallel clustering method, a two-stage Map Reduce implementation framework is proposed. Each of the stage is implemented by one kind Map Reduce task. In the first stage, the DNS query logs are divided into multiple splits and the CLOPE algorithm is executed on each split. The second stage usually tends to iterate many times to merge the small clusters into bigger satisfactory ones. In these two stages, a novel partition process is designed to randomly spread out original sub clusters, which will be moved and merged in the map phrase of the second phase according to the defined merge criteria. In such way, the advantage of the original CLOPE algorithm is kept and its disadvantages are dealt with in the proposed framework to achieve more excellent clustering performance. The experiment results show that MR-CLOPE is not only faster but also has better clustering quality on DNS query logs compared with CLOPE. 展开更多
关键词 DNS data mining MR-CLOPE algorithm transactional clustering algorithm Map Reduce framework
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Correlation analysis-based image segmentation approach for automatic agriculture vehicle 被引量:1
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作者 张方明 应义斌 +1 位作者 蒋焕煜 SHIN Beom-soo 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1158-1162,共5页
It is important to segment image correctly to extract guidance information for automatic agriculture vehicle. If we can make the computer know where the crops are, we can extract the guidance line easily. Images were ... It is important to segment image correctly to extract guidance information for automatic agriculture vehicle. If we can make the computer know where the crops are, we can extract the guidance line easily. Images were divided into some rec-tangle small windows, then a pair of 1-D arrays was constructed in each small windows. The correlation coefficients of every small window constructed the features to segment images. The results showed that correlation analysis is a potential approach for processing complex farmland for guidance system, and more correlation analysis methods must be researched. 展开更多
关键词 Image segmentation Machine vision Correlation analysis GUIDANCE
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Free Energy Level Correction by Monte Carlo Resampling with Weighted Histogram Analysis Method
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作者 Seyoung Chung Sun Mi Choi +2 位作者 Wook Lee Kwang Hyun Cho Young Min Rhee 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第2期183-195,I0003,I0010-I0017,共22页
Free energy calculations may provide vital information for studying various chemical and biological processes.Quantum mechanical methods are required to accurately describe interaction energies,but their computations ... Free energy calculations may provide vital information for studying various chemical and biological processes.Quantum mechanical methods are required to accurately describe interaction energies,but their computations are often too demanding for conformational sampling.As a remedy,level correction schemes that allow calculating high level free energies based on conformations from lower level simulations have been developed.Here,we present a variation of a Monte Carlo(MC)resampling approach in relation to the weighted histogram analysis method(WHAM).We show that our scheme can generate free energy surfaces that can practically converge to the exact one with sufficient sampling,and that it treats cases with insufficient sampling in a more stable manner than the conventional WHAM-based level correction scheme.It can also provide a guide for checking the uncertainty of the levelcorrected surface and a well-defined criterion for deciding the extent of smoothing on the free energy surface for its visual improvement.We demonstrate these aspects by obtaining the free energy maps associated with the alanine dipeptide and proton transfer network of the KillerRed protein in explicit water,and exemplify that the MC resampled WHAM scheme can be a practical tool for producing free energy surfaces of realistic systems. 展开更多
关键词 Free energy level correction Weighted histogram analysis method Monte Carlo resampling
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Multi-resolution graph-based clustering analysis for lithofacies identifi cation from well log data: Case study of intraplatform bank gas fi elds, Amu Darya Basin 被引量:13
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作者 Tian Yu Xu Hong +4 位作者 Zhang Xing-Yang Wang Hong-Jun Guo Tong-Cui Zhang Liang-Jie Gong Xing-Lin 《Applied Geophysics》 SCIE CSCD 2016年第4期598-607,736,共11页
In this study, we used the multi-resolution graph-based clustering (MRGC) method for determining the electrofacies (EF) and lithofacies (LF) from well log data obtained from the intraplatform bank gas fields loc... In this study, we used the multi-resolution graph-based clustering (MRGC) method for determining the electrofacies (EF) and lithofacies (LF) from well log data obtained from the intraplatform bank gas fields located in the Amu Darya Basin. The MRGC could automatically determine the optimal number of clusters without prior knowledge about the structure or cluster numbers of the analyzed data set and allowed the users to control the level of detail actually needed to define the EF. Based on the LF identification and successful EF calibration using core data, an MRGC EF partition model including five clusters and a quantitative LF interpretation chart were constructed. The EF clusters 1 to 5 were interpreted as lagoon, anhydrite flat, interbank, low-energy bank, and high-energy bank, and the coincidence rate in the cored interval could reach 85%. We concluded that the MRGC could be accurately applied to predict the LF in non-cored but logged wells. Therefore, continuous EF clusters were partitioned and corresponding LF were characteristics &different LF were analyzed interpreted, and the distribution and petrophysical in the framework of sequence stratigraphy. 展开更多
关键词 Multi-resolution graph-based clustering method electrofacies lithofacies intraplatform bank gas fields Amu Darya Basin
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基于DRGEPSA方法的甲烷燃烧简化机理的构建及验证
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作者 徐传义 邵亚丽 +3 位作者 卢平 宋涛 张海楠 黄震 《上海电力大学学报》 CAS 2022年第5期415-420,426,共7页
采用耦合误差传播和敏感性分析的直接关系图(DRGEPSA)法,对甲烷燃烧详细反应机理(Gri Mech 3.0机理)进行了简化,构建出了一套含有23种组分和110步基元反应的简化机理。为验证该简化机理的合理性和可靠性,采用充分搅拌反应器模型和一维... 采用耦合误差传播和敏感性分析的直接关系图(DRGEPSA)法,对甲烷燃烧详细反应机理(Gri Mech 3.0机理)进行了简化,构建出了一套含有23种组分和110步基元反应的简化机理。为验证该简化机理的合理性和可靠性,采用充分搅拌反应器模型和一维层流预混反应器模型分别对甲烷燃烧反应过程进行模拟,并对温度和组分摩尔分数分布进行了对比分析。结果显示:利用简化机理分析得到的预测数据与详细机理吻合良好。结合该简化机理,建立了二维数值模型对带伴流的甲烷/空气Flame D进行数值模拟仿真研究,流场的温度和组分分布均与实验值吻合度较好,进一步表明所提甲烷燃烧简化机理具有较高的模拟精度。 展开更多
关键词 机理简化 甲烷 耦合误差传播和敏感性分析的直接关系图法 燃烧数值模拟
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Impact of renal transplantation on cardiac morphological and functional characteristics in children and adults
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作者 Sahier Omar El-Khashab Eman El-Sayed Mohamed +2 位作者 Mahmoud A Soliman Hussein Heshmat Kassem Amin Roshdy Soliman 《World Journal of Nephrology》 2016年第6期517-523,共7页
AIM To compare the effects of renal transplantation on cardiac functions in children and adults.METHODS One hundred and ten patients attending the nephrology outpatient clinic were enrolled in this study and were divi... AIM To compare the effects of renal transplantation on cardiac functions in children and adults.METHODS One hundred and ten patients attending the nephrology outpatient clinic were enrolled in this study and were divided into six groups. The first two groups consisted each of 30 renal transplant patients who had a successful renal transplantation more than six months, but less than one year. Group Ⅰ were less than 18 years and group Ⅱ were more than 18 years. The third and fourth groups, each were 20 chronic renal failure patients on regular hemodialysis. Again, group Ⅲ were less than 18 years and group Ⅳ were more than 18 years. Group Ⅴ and Ⅵ(The control Groups) consisted each of 5 subjects below and above 18 years of age, respectively with normal kidney functions. All patients were subjected to history and examination. The kidney functions and the hemoglobin were analyzed. Afterobtaining informed consent, echocardiography was done to all patients.RESULTS There was a statistically significant improvement(P < 0.0001) in all cardiac parameters. A regression in left ventricular end diastolic volume(LVED) both in children(4.7 ± 0.8 to 4.2 ± 0.5) and in adults(5.9 ± 0.7 to 4.9 ± 0.6) were found. There was a regression in left ventricular end systolic volume(LVES) both in children(3.1 ± 0.6 to 2.4 ± 0.4) and in adults(4.1 ± 0.9 to 3.1 ± 0.5). Fractional shortening improves both in children(32.6 ± 5.3 to 41.7 ± 7.6) and in adults(29.0 ± 6.6 to 36.5 ± 4.1). The improvement in ejection fraction(EF) was higher in children(59.7 ± 7.0 to 71.9 ± 6.1) than in adults(52.0 ± 12.5 to 64.8 ± 5.9). However, this degree of improvement(in children: 12.2 ± 5.1) did not show statistical difference(P-value 0.8), when compared to adults(12.7 ± 9.8). CONCLUSION After renal transplantation cardiac functions and morphology(EF/LVED/LVES) do improve markedly and rapidly in both children and adults. 展开更多
关键词 Echocardiography chronic renal disease Renal transplantation Cardiac problems
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Teaching method for reading views by analyzing lines and planes
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作者 张庆伟 《Journal of Chongqing University》 CAS 2006年第3期137-142,共6页
This paper deals with the teaching method in reading engineering drawing. It introduces the basic theory and fundamental ideas as well as the approach of reading views by analyzing lines and planes. It gives out the s... This paper deals with the teaching method in reading engineering drawing. It introduces the basic theory and fundamental ideas as well as the approach of reading views by analyzing lines and planes. It gives out the steps for completing the third view based on the other two views. As it is easy and quick for students to read and understand views by this method, it is welcome by students in teaching practice. 展开更多
关键词 projection rule reading view analyzing lines and planes: parallel PERPENDICULAR
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HYPOXIA CONCOMITANT WITH SERUM DEPRIVATION INDUCES ENDOTHELIAL PROGENITOR CELL DEATH
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作者 连锋 顾萍 +2 位作者 范关荣 薛松 朱洪生 《Medical Bulletin of Shanghai Jiaotong University》 CAS 2010年第1期10-14,共5页
Objective To evaluate the effects endothelial progenitor cells (EPCs) survival in vitro of serum deprivation (SD) and hypoxia on the bone marrow Methods Rat bone marrow EPCs were exposed for 48 h to 02 deprivation... Objective To evaluate the effects endothelial progenitor cells (EPCs) survival in vitro of serum deprivation (SD) and hypoxia on the bone marrow Methods Rat bone marrow EPCs were exposed for 48 h to 02 deprivation, serum deprivation ( SD ) , and prolonged ( 120 h) hypoxia concomitant with serum deprivation. Cell death was assessed by Live/Dead staining and image analysis. Reaulta The EPCs death rate seemed not affected by 48 h hypoxia ( P 〉 0. 05 ), but affected by SD ( P 〈 0. 01 ). Prolonged hypoxia concomitant with SD resulted in the death of nearly all EPCs from 72 h, but this rate was remarkably reduced when with 20% fetal bovine serum( P 〈 0. 01 ). Conclusion Our findings indicate that EPCs are sensitive to hypoxia/SD stimuli, while serum may be the more important factor for EPCs survival. 展开更多
关键词 endothelial progenitor cells hypoxia serum deprivation
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Positioning of grid points in wave front construction 被引量:6
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作者 Han Fuxing Sun Jianguo +1 位作者 Sun Zhangqing Yang Hao 《Applied Geophysics》 SCIE CSCD 2009年第3期248-258,300,共12页
In view of the relative positioning problem between non-regular quadrilateral grids and regular rectangle grid nodes in the wave front construction method, concrete realization problems with four grid positioning meth... In view of the relative positioning problem between non-regular quadrilateral grids and regular rectangle grid nodes in the wave front construction method, concrete realization problems with four grid positioning methods (vector cross product judgment, angle sum, intersection-point, and signs comparison algorithms) in wave front construction which are commonly used in computer graphics are compared and analyzed in this paper. Based on the stability analysis of the location method, the calculation examples show that the vector cross product judgment method is faster and more accurate than other methods in the realization of the relative positioning between non-regular quadrilateral grids and regular rectangle grid nodes in wave front construction. It provides precise grid point attribute values for the next steps of migration and demigration. 展开更多
关键词 wave front construction grid localization grid nodes wave front quadrilateral
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