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Search Results: 1 - 10 of 508432 matches for " <br>刘文燕 "
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ANALYSIS ON SAFETY FACTOR OF ANCHORED ROCK MASSES
支护岩体滑移安全系数分析

Peng Wenxuan,Liu Dongyan,Yang Jianguo,<br>彭,,杨建国
岩石力学与工程学报 , 2002,
Abstract: Constitutive model is established to take the slide surface, tear or yield of the layer into account comprehensively. With this model, the safety factor of anchored rock masses is determined against integrate slide and compared with that obtained by limit equilibrium theory.
功能性核磁成像技术在脊髓型颈椎病患者中应用及其临床意义
Functional Magnetic Resonance Imaging Application and Its Clinical Significance in the Spondylotic Myelopathy
 [PDF]

齐勇, , 林冠
Hans Journal of Surgery (HJS) , 2016, DOI: 10.12677/HJS.2016.53007
Abstract:
目的:探究功能性核磁成像技术在脊髓型颈椎病患者中应用及其临床意义。方法:选择2014年1月至2014年6月我院骨科收治的脊髓型颈椎病患者为观察对象,选择同期10例健康志愿者为对照组对象。在术前、术后6周、3月及其6月分别进行一次fMRI脑功能成像并根据日本骨科学会评分系统(JOA scores)对术后恢复情况进行评估。对照组对象同期行脑fMRI功能成像。比较两组不同时间点脑fMRI功能成像、JOA 评分和术后恢复(步长,动作完成时间)。结果:对照组健康对象在完成指定动作时,在对侧脑部主要运动区都有局部有限的皮质激活区域。脊髓型颈椎病患者fMRI图像表明激活的皮质映射区域与健康对照组相比有所扩大。脊髓减压术后皮质激活映射区有所缩小并接近健康组激活区域范围。与对照组比较,枕叶、额叶及其边缘系统是观察组患者ReHo显著降低的脑区;小脑及其边缘叶是观察组ReHo显著升高的脑区。JOA评分和术后恢复观察组患者明显(P < 0.05)。结论:fMRI可作为脊髓型颈椎病患者术前和术后皮质投射区变化的有效评定方法,通过此FMRI的评估可以有效的进行患者术后评估和术后恢复指导。
Objective: To explore the functional magnetic resonance imaging application and its clinical significance in the spondylotic myelopathy. Methods: 10 cases spondylotic myelopathy patients treated in the orthopaedic department of our hospital from January 2014 to June 2014 were selected as the observation objects, and 10 cases healthy volunteers were selected as the control objects in the same period. Functional magnetic resonance imaging and the Japanese orthopaedic society of scoring system (JOA scores) evaluating the postoperative recovery were measured in the preoperative and postoperative 6 weeks, 3 months and 6 months, respectively. The control objects in the same period were measured by functional magnetic resonance imaging. Functional magnetic resonance imaging and JOA score and postoperative recovery (time step, action) were compared between two groups at different time points. Results: The limited areas of the cortex were activated at main motor areas on the side of the brain after completing the action in the control objects. Activation of cortical map area in functional magnetic resonance imaging of the spondylotic myelopathy patients widened compared with the healthy controls. Cortical activation mapping area reduced activation area and close to the healthy group after the spinal cord decompression. Compared with the control group, the occipital lobe, the frontal lobe and the limbic system were the areas of the brain that ReHo of the observation group patients significantly reduced. The cerebellum and the edge of leaf were the areas of the brain that ReHo of the observation group patients significantly increased. The JOA score and post-operation of the observation group are more significant than those of the control group (P < 0.05). Conclusion: Functional magnetic resonance imaging can be effective evaluation methods for the preoperative and postoperative cortical projection area changes in the spondylotic myelopathy patients’ cerebral cortex. We can evaluate the postoperative
Relationship of all size-fractionated phytoplankton with environmental factors after bioremediation in black and feculent water
黑臭水体生物修复中各粒级浮游植物与环境因子的关系

LIU Dong-Yan,ZHAO Min,LIN Wen-Peng,<br>,赵敏,
水生生物学报 , 2009,
Abstract: The relationships between organism and its surroundings have been widely adopted to evaluate the health of eco-system. Through the analysis of the size-fractionated phytoplankton in black and feculent water, it discussed the effect of bioremediation on all size-fractionated phytoplankton and the relationship of all size-fractionated chlorophyll-α with envi-ronmental factors to bioremediation, so as to provide biological proof for illustrating the efficiency of measures taken for the bioremediation.Comprehensive measures concerning ecology including the way of adding bioenergizer, biologic algaecide, effective microbe into water, and planting macrophyte are adopted. Group A is the contrast group, does not use any measures; Group B, C, D, E, F and G are test groups. Group B add photosynthetic bacteria and nitrifying bacteria; Group C add photosynthetic bacteria nitrifying bacteria and oxygen strengthen; Group D add photosynthetic bacteria nitrifying bacteria bioenergizer and oxygen strengthen ; Group E add photosynthetic bacteria nitrifying bacteria bioenergizer plant Eichhornia crassipes and oxygen strengthen; Group F add photosynthetic bacteria nitrifying bacteria bioenergizer and plant Eichhornia crassipes ; Group G add bioenergizer and oxygen strengthen. Beforehand, background was sampled twice on 28th of August in 2002. The experiment began from August 29, 2002. And after the engineering project, samples for water quality analyses were collected on the 29th and 31st of August, the 3rd, 6th , 9th, 12th and 17th of September respectively. Water samples for phytoplankton analyses were collected with length Niskin bottles ( for a total final volume of 10L). The samples were divided into Pico (0.2-2.0 μm), Ultra (0.2-5 μm), Nano (2-20 μm) and Net (20-200 μm) size fractions by filtration. Chlorophyll-a was determined by spectrophotometry following the methods proposed by Lorenzen on the 9th, 12th and 17th of September in 2002 respectively. Within the periods of this survey, both of CODcr and BOD5 lowered after bioremediation and the effect of cleansing were very significantly in group C, D and E, the removal rates of NH, were 71.3% , 84.0% and 93.2% ; TP were 5.2% , 64.6% and 78.0% ; TN were 46.2% , 50.3% and 75.5% separately in the three groups and the effect of group E was the best. CODcr, NH, and TP were decreased significantly compared with the contrast group A (p < 0.05 ). Bivari-ate correlate analyze was done between the content of all size-fractionated chlorophyll-a, the percentages of all size frac-tionated contents to bulk contents with all environmental factors. The result showed that the percentages of Net-Chla% significantly negatively correlated with CODcr,TN, NH, and TP and positively with NO2-N and NO3-N, while the percentage of Nano-Chla% and Pico-Chla% positively correlated with CODcr, TN, NH, and TP and negatively with NO2-N and NO3-N. As both of the TN and NH4, TP and COD are indexes reflecting the level of the water contamination
Effect of Suining Tributary ecoremediation to all size-fractionated chlorophyll-a contents
绥宁河生态修复对粒径分级叶绿素a的影响

LIU Dongyan,DA Liangjun,YOU Wenhui,SONG Yongchang,<br>,达良俊,,宋永昌
应用生态学报 , 2003,
Abstract: Through analysis of the size fractionated chlorophyll a contents in the remedied part,control part and non remedied part in Suining Tributary,this paper discussed the effect of bioremediation to all size fractionated chlorophyll a contents. The averaged Chlorophy a content of nano plus pico phytoplankton made up 85.232%, 92.402 %,95.205% of the total,respectively for the remedied, control and non remedied part. Among these,the nano fraction alone made up 78.460%,87.943%,87.211%,respectively. Nano phytoplankton contributed most to the total biomass of Chl a. Its average contribution was 84.538% to the whole tributary,whereas net phytoplankton contributed only 9.054%. Nano and pico phytoplankton was most sensitive to the test eco remedy. The remedy reduced the relative biomass of net phytoplankton,and increased the relative biomass of Pico enhance. The relative biomass of nano and ultrta phytoplankton fraction was little effected.
Effects of 4PU on the Senescence of Detached Radish Cotyledons
4PU对萝卜离体子叶衰老的影响

Zhu Chen,Liu Fei-yan,Zeng Guang-wen,<br>朱诚,,曾广
植物学报 , 1997,
Abstract: Radish (Raphanus sativus) cotyledons were used as experimental material for investigating effects of the leaf senescence by 4PU N-phenyl-N'-(4-pyridyl) urea]. 4PU treatment could retard the senescence of detached cotyledons. The contents of chlorophyll and protein in detached cotyledons treated with 4PU decreased slower than those of the control (in H20). The best concentration of 4PU was 10-1 mg/L.
Effect of Nano-Diamond Particulates on the Microstructure and Wear-Resistance of Electrodeposited Ni-Matrix Coatings
纳米金刚石对电沉积镍基复合镀层微观结构及抗磨性能的影响

WANG Li-ping~,<br>王立平,,薛群基,,徐洮
摩擦学学报 , 2004,
Abstract: The microcrystalline Ni- and nanocrystalline Ni-based composite coatings incorporated with diamond nano-particulates were prepared making used of electrodeposition. The effect of the nano-diamond particulates on the surface morphology, microstructure, hardness, and wear-resistance of the two types of Ni-matrix coatings were investigated. Thus the Ni-matrix coatings with and without the nano-diamond particulates were characterized by means of X-ray diffraction and scanning electron microscopy. The friction and wear behaviors of the coatings sliding against AISI1045 steel under unlubricated condition in a ball-on-disc configuration were evaluated using a UMT-2MT friction and wear tester. The worn surfaces morphologies of the coatings were also analyzed by means of scanning electron microscopy. It was found that the incorporation of the nano-diamond particulates contributed to greatly increase the hardness and wear resistance of the microcrystalline Ni-matrix coating, but it had little effect on the hardness of the nanocrystalline Ni-matrix coating. Moreover, the nano-diamond particulates were harmful to the wear-resistance of the nanocrystalline Ni-matrix coating. The increased wear-resistance of the microcrystalline Ni-matrix coating in the presence of the nano-diamond particulates was attributed to the dispersive strengthening effect of the nnaoparticulates, which helped to increase the ability of the coating to resist plastic deformation and adhesion as well.
基于多任务联合稀疏和低秩表示的高分辨率遥感图像分类
High Resolution Remote Sensing Image Classification Using Multitask Joint Sparseand Low-rank Representation

, 祁昆仑, 吴柏, 吴华意<br>LIU Wenxuan, QI Kunlun, WU Baiyan, WU Huayi
- , 2018, DOI: 10.13203/j.whugis20160044
Abstract: 多任务学习(multitask learning,MTL)是一种利用多个任务间共享信息并行学习以提高模型泛化性能的机器学习方法,研究表明该方法可以提升高分辨率遥感图像的分类精度。提出一种基于多任务联合稀疏和低秩表示(multitask joint sparse and low-rank representation,MJSLR)的高分辨率遥感图像分类模型,并采用加速近似梯度法求解凸的光滑函数和非光滑约束的组合优化问题。实验对比分析了多任务和单任务的学习模型,并比较了MJSLR、多核学习方法和多任务联合稀疏表达方法的图像分类准确率,结果表明多任务学习模型能够获得优于单任务学习模型的分类精度,而且融合低秩约束能够一定程度上提高多任务分类模型的精度
某超高层办公楼结构设计

工业建筑 , 2014, DOI: 10.13204/j.gyjz2001412027
Abstract: 某超限高层办公楼地下3层,地上57层,结构主屋面高度为296m,采用带加强层的钢-混凝土混合框架-核心筒结构体系。采用ETABS和PMSAP等软件进行多遇地震弹性分析和楼盖舒适度验算。结果表明,结构的周期比、层间位移角、楼板舒适度均满足要求。伸臂桁架典型节点有限元分析结果表明,节点区应力低于钢材设计强度,没有出现应力集中现象。为保证结构“大震不倒”的目标,采用Perform3D软件分析结构在罕遇地震下的反应,结果表明,核心筒、框架柱和伸臂桁架均未屈服,少量框架梁和连梁屈服,结构整体性能、构件变形和耗能指标均符合要求。
Study on the thermal interface resistance of the helix slow-wave structure
螺旋线慢波结构中界面热阻率的研究

Han Yong,Liu Yan-Wen,Ding Yao-Gen,Liu Pu-Kun,<br>韩勇,,丁耀根,濮鲲
物理学报 , 2009,
Abstract: 通过理论和实验的方法,对螺旋线慢波结构中的界面热阻率进行了研究.分析了两个接触处的界面热阻率对慢波结构散热性能的不同影响.提出了一种计算界面热阻率的方法,并对其准确性和可行性进行了验证.该方法可以分别估算两个接触处的界面热阻率,并考虑了组件材料属性随温度变化的特性.利用该方法研究了夹持杆材料和装配方法对螺旋线慢波结构界面热阻率的影响.
Effect of the nanopariculate metal film on heat radiation
金属纳米粒子薄膜对辐射散热的影响的研究

Han Yong,Liu Yan-Wen,Ding Yao-Gen,Liu Pu-Kun,<br>韩勇,,丁耀根,濮鲲
物理学报 , 2010,
Abstract: The effect of the nanoparticulate metal film on the heat radiation performance has been studied by evaluating the thermal conduction of different helix slow-wave structures (SWS). The heat dissipation capabilities of the SWSs with normal barrel, with normal Ir film deposited barrel and nano-Ir deposited barrel have been analyzed and compared by experiments and simulations. With the measured data, the radiation emissivities of the employed materials have been estimated, and the accuracy has been verified by computer simulation. The experimental results and the simulation results make perfect agreement, suggesting that the nanoparticulate metal film gives much better heat radiation performance.
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