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运用中风中医症征积分量表探讨中西医结合卒中单元对脑卒中患者生活质量的影响 被引量:12
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作者 张红智 张秋娟 +1 位作者 鲍春龄 张云云 《辽宁中医杂志》 CAS 北大核心 2011年第11期2126-2129,共4页
目的:通过前瞻性、多中心、队列对照的研究方法,运用中风中医症征积分量表客观地评价中西医结合卒中单元对卒中患者生活质量的影响。方法:将北京、上海四家三甲医院收集的120例急性缺血性脑卒中患者分为中西医结合卒中单元试验组和西医... 目的:通过前瞻性、多中心、队列对照的研究方法,运用中风中医症征积分量表客观地评价中西医结合卒中单元对卒中患者生活质量的影响。方法:将北京、上海四家三甲医院收集的120例急性缺血性脑卒中患者分为中西医结合卒中单元试验组和西医卒中单元对照组,每组各60例。试验组在单纯西医卒中单元常规治疗的基础上,早期介入中药、针灸、推拿、康复等为一体中西医结合综合治疗方案;对照组为西医卒中单元常规治疗结合早期康复锻炼,疗程为21天,客观评价两组之间在改善中风患者中医症状严重程度以及对日常生活影响程度方面的临床疗效。结果:中西医结合卒中单元在改善中风患者中医症状积分及中风症状对日常生活影响程度积分方面明显优于西医卒中单元对照组(P<0.05,P<0.001)。结论:中西医结合卒中单元改善缺血性中风患者中医症征积分方面具有良好的临床疗效。 展开更多
关键词 中西医结合卒中单元 中风病 中风中医症征积分量
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腰椎术后不同便秘症状积分患者的护理 被引量:9
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作者 林玲 罗春梅 骆书兰 《护理学杂志》 2011年第24期37-38,共2页
目的总结腰椎术后不同便秘症状积分患者的护理方法。方法将90例腰椎术后患者随机分为对照组和观察组各45例。对照组采用常规护理;观察组采用便秘症状积分量表对便秘症状进行评分,再根据评分结果对不同积分类别患者有针对性地采取饮食调... 目的总结腰椎术后不同便秘症状积分患者的护理方法。方法将90例腰椎术后患者随机分为对照组和观察组各45例。对照组采用常规护理;观察组采用便秘症状积分量表对便秘症状进行评分,再根据评分结果对不同积分类别患者有针对性地采取饮食调整、腹部按摩、药物应用等护理干预。结果两组患者便秘及其伴随症状发生率比较,差异有统计学意义(均P<0.01)。结论采用便秘症状积分量表评分并采取相应的护理干预,有利于患者便秘缓解。 展开更多
关键词 腰椎 手术 便秘 便秘症状积分量 护理
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一种实现CCD亚像元位移分辨率的新方法 被引量:8
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作者 姚新程 李兆霖 +2 位作者 郭红莲 程丙英 张道中 《仪器仪表学报》 EI CAS CSCD 北大核心 2002年第1期60-63,共4页
基于 CCD子窗口内四个像限的光积分量随目标位置而变化的机理 ,可从摄取的 CCD数字图像提取目标的位移信号 ,本文提出一种新的方法可实现目标位移探测的亚像元分辨率。理论及实验结果表明 ,对于直径为 1μm的球体而言 ,在± 40 0 n... 基于 CCD子窗口内四个像限的光积分量随目标位置而变化的机理 ,可从摄取的 CCD数字图像提取目标的位移信号 ,本文提出一种新的方法可实现目标位移探测的亚像元分辨率。理论及实验结果表明 ,对于直径为 1μm的球体而言 ,在± 40 0 nm的范围内 ,光积分量的变化同球体的位移关系具有良好的线性度。物方和像方位移分辨率分别可达 1nm和 1/ 3 0个像元宽度 ,可满足光镊系统位移测量要求。 展开更多
关键词 CCD 亚像元 光镊 分辨率 积分量 位移测量
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一种基于最近电平调制方式的MMC电压均衡改进方法 被引量:8
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作者 刘追 刘振兴 李翠 《电测与仪表》 北大核心 2017年第24期87-93,共7页
最近电平逼近是模块化多电平换流器的主要调制策略之一,在电平数较多的换流器中具有明显的优势。为保证均压效果,通常都需要实时采集各个子模块的电容电压进行排序,在实际工程中则需要大量的电压采集模块来实现。针对上述问题,提出了一... 最近电平逼近是模块化多电平换流器的主要调制策略之一,在电平数较多的换流器中具有明显的优势。为保证均压效果,通常都需要实时采集各个子模块的电容电压进行排序,在实际工程中则需要大量的电压采集模块来实现。针对上述问题,提出了一种替换方法,即通过桥臂电流对各个子模块投入时间的积分量来进行排序,间接实现了电容电压排序的效果,这种方法可以有效的减少传感器的数量。同时,在提出的替换方法的基础上,引入子模块间允许的电压最大偏差,在系统输出特性允许范围的前提下,大大的降低了因排序而导致的IGBT开关频率。最后通过RT-LAB仿真平台搭建了21电平的的MMC仿真模型,对两种电压均衡方法下IGBT开关频率和子模块电容电压进行比较,仿真结果验证了所提方法的可行性及有效性。 展开更多
关键词 最近电平调制 均压 积分量 电压最大偏差
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拟有限元法及其在板带热轧中的应用 被引量:1
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作者 李立新 汪凌云 《武汉科技大学学报》 CAS 2004年第2期116-119,共4页
以轧制方向单元节点速度Vx为未知量,采用Hill提出的稳态轧制过程中轧材宽度、厚度方向金属流动速度Vy,Vz与Vx的函数关系,从可压缩材料的变分原理出发来求解轧制变形区中的场变量及其积分量。由热轧轧制压力实测值及计算值的比较表明,其... 以轧制方向单元节点速度Vx为未知量,采用Hill提出的稳态轧制过程中轧材宽度、厚度方向金属流动速度Vy,Vz与Vx的函数关系,从可压缩材料的变分原理出发来求解轧制变形区中的场变量及其积分量。由热轧轧制压力实测值及计算值的比较表明,其计算精度较高,便于实际应用。 展开更多
关键词 有限元法 板带热轧 变形过程 场变量 积分量
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地基微波辐射计遥感人工触发闪电的观测研究 被引量:1
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作者 姜苏麟 王振会 +7 位作者 刘超 雷连发 潘赟 李青 张义军 吕伟涛 陈绍东 卢建平 《热带气象学报》 CSCD 北大核心 2023年第4期497-506,共10页
为了深入研究雷电产生的微波热辐射特征,从2016年初夏开始利用地基微波辐射计在中国气象局雷电野外科学实验基地开展了连续4年的观测实验,根据雷电热效应的特征,制定了观测方案,并为地基微波辐射计设置了“引雷观测模式”。结果表明,地... 为了深入研究雷电产生的微波热辐射特征,从2016年初夏开始利用地基微波辐射计在中国气象局雷电野外科学实验基地开展了连续4年的观测实验,根据雷电热效应的特征,制定了观测方案,并为地基微波辐射计设置了“引雷观测模式”。结果表明,地基微波辐射计具有对雷电热效应产生响应的能力。2017—2019年,辐射计一共成功捕获了30次人工触发闪电,观测效率逐年增长,平均为71.4%;微波亮温脉冲幅度的最大值约125K。结合其中28次触发事件的雷电流数据,分析了亮温脉冲幅度和雷电流积分量之间的相关性,并发现了最大亮温脉冲幅度与总电流作用积分之间可能存在指数关系。根据亮温观测数据估算了雷电热效应的持续时间,平均约0.5 s,其中25次触发事件的雷电流热效应持续时间与雷电流持续时间变化较为一致,相关系数约0.73。 展开更多
关键词 地基微波辐射计 人工触发闪电 雷电热效应 亮温脉冲 雷电流积分量
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Quantum key distribution and controlled quantum direct communication applying product state of qutrit 被引量:20
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作者 ZHU Ai-dong ZHANG Shou 《量子电子学报》 CAS CSCD 北大核心 2007年第3期316-322,共7页
On basis of the nonlocality without entanglement proposed by Bennett,the properties of an orthogonal set of product states of two qutrits are revealed,i.e.,the transformation among different composite spaces can be re... On basis of the nonlocality without entanglement proposed by Bennett,the properties of an orthogonal set of product states of two qutrits are revealed,i.e.,the transformation among different composite spaces can be realized by using three unitary operations,and the correlation between two composite spaces is found.These properties can be used to quantum communication and quantum cryptography.As examples,we propose a scheme of controlled quantum secure direct communication and one of quantum key distribution.It is shown that applying the product state of qutrit to quantum information processing not only is of the advantages of large capacity and high efficiency,but ensures the security. 展开更多
关键词 quantum information NONLOCALITY QUTRIT product state quantum communication quantum key distribution
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Computation and measurement for distributions of temperature and soot volume fraction in diffusion flames 被引量:1
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作者 张引弟 娄春 +2 位作者 谢明亮 方庆艳 周怀春 《Journal of Central South University》 SCIE EI CAS 2011年第4期1263-1271,共9页
A combined computational and experimental investigation to examine temperature and soot volume fraction in coflow ethylene-air diffusion flames was presented.A numerical simulation was conducted by using a relatively ... A combined computational and experimental investigation to examine temperature and soot volume fraction in coflow ethylene-air diffusion flames was presented.A numerical simulation was conducted by using a relatively detailed gas-phase chemistry and complex thermal and transport properties coupled with a semi-empirical two-equation soot model.Thermal radiation was calculated using the discrete ordinates method.An image processing technique and a decoupled reconstruction method were used to simultaneously measure the distributions of temperature and soot volume fraction.The results show that the maximum error for temperature does not exceed 10% between the prediction and the measurement.And the maximum error is 6.9% for soot volume fraction between prediction and measurement.Additional simulations were performed to explore the effects of global equivalence ratio on diffusion flames and the soot formation.The results display that the soot formation increases with decreasing the coflow air velocity.And the soot formation in each case appears in the annular region,where the temperature ranges from about 1 000 K to 2 000 K and the profile becomes taller and wider when the coflow air is decreased. 展开更多
关键词 TEMPERATURE soot volume fraction SIMULATION MEASUREMENT diffusion flame
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Photocatalytic oxidation of nitric oxide from simulated flue gas by wet scrubbing using ultraviolet/TiO_2/H_2O_2 process 被引量:2
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作者 张波 仲兆平 付宗明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期82-87,共6页
Nitric oxide(NO) from flue gas is hard to remove because of low solubility and reactivity. A new technology for photocatalytic oxidation of NO using ultraviolet(UV)/TiO2/H2O2 process is studied in an efficient laborat... Nitric oxide(NO) from flue gas is hard to remove because of low solubility and reactivity. A new technology for photocatalytic oxidation of NO using ultraviolet(UV)/TiO2/H2O2 process is studied in an efficient laboratory-scale reactor. Effects of several key operational parameters on NO removal efficiency are studied, including TiO2 content, H2O2 initial concentration, UV lamp power, NO initial content, oxygen volume fraction and TiO2/H2O2 solution volume. The results illustrate that the NO removal efficiency increases with the increasing of H2O2 initial concentration or UV lamp power. Meanwhile, a lower NO initial content or a higher TiO2/H2O2 solution volume will result in higher NO removal efficiency. In addition, oxygen volume fraction has a little effect.The highest NO removal efficiency is achieved at the TiO2 content of 0.75 g/L, H2O2 initial concentration of 2.5 mol/L, UV lamp power of 36 W, NO initial content of 206×10-6 and TiO2/H2O2 solution volume of 600 m L. It is beneficial for the development and application of NO removal from coal-fired flue gas with UV/TiO2/H2O2 process. 展开更多
关键词 photocatalytic oxidation nitric oxide UV/TiO2/H2O2 process
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Parametric analysis of mixed lubrication characteristics in work zone of strip rolling 被引量:3
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作者 吴建清 梁小平 潘复生 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3153-3159,共7页
A theoretical model for mixed lubrication with more accurate contact length has been developed based on the average volume flow model and asperity flattening model,and the lubricant volume flow rate and outlet speed r... A theoretical model for mixed lubrication with more accurate contact length has been developed based on the average volume flow model and asperity flattening model,and the lubricant volume flow rate and outlet speed ratio are determined by integrating differential equations based on rolling parameters.The lubrication characteristics at the roll-strip interface with different surface roughness,rolling speed,reduction and lubricant viscosity are analyzed respectively.Additionally,the average volume flow rates of lubricant under different rolling conditions are calculated and used to explain the change rule of lubrication characteristics.The developed scheme is able to determine the total pressure,lubricant pressure,film thickness and real contact area at any point within the work zone.The prediction and analysis of mixed lubrication characteristics at the interface is meaningful to better control the surface quality and optimize the rolling process. 展开更多
关键词 mixed lubrication ROLLING film thickness real contact area
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Correspondence of bubble size and frother partitioning in flotation 被引量:5
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作者 张炜 Jan E.Nesset James A.Finch 《Journal of Central South University》 SCIE EI CAS 2014年第6期2383-2390,共8页
The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most impor... The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction. 展开更多
关键词 FLOTATION frother bubble size frother partitioning total organic carbon (TOC) analysis concentration gradient
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Resolution performance analysis of cumulants-based rank reduction estimator in presence of unexpected modeling errors
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作者 王鼎 吴瑛 《Journal of Central South University》 SCIE EI CAS 2013年第11期3116-3130,共15页
Compared to the rank reduction estimator (RARE) based on second-order statistics (called SOS-RARE), the RARE employing fourth-order cumulants (referred to as FOC-RARE) is capable of dealing with more sources and... Compared to the rank reduction estimator (RARE) based on second-order statistics (called SOS-RARE), the RARE employing fourth-order cumulants (referred to as FOC-RARE) is capable of dealing with more sources and mitigating the negative influences of the Gaussian colored noise. However, in the presence of unexpected modeling errors, the resolution behavior of the FOC-RARE also deteriorate significantly as SOS-RARE, even for a known array covariance matrix. For this reason, the angle resolution capability of the FOC-RARE was theoretically analyzed. Firstly, the explicit formula for the mathematical expectation of the FOC-RARE spatial spectrum was derived through the second-order perturbation analysis method. Then, with the assumption that the unexpected modeling errors were drawn from complex circular Gaussian distribution, the theoretical formulas for the angle resolution probability of the FOC-RARE were presented. Numerical experiments validate our analytical results and demonstrate that the FOC-RARE has higher robustness to the unexpected modeling en'ors than that of the SOS-RARE from the resolution point of view. 展开更多
关键词 performance analysis rank reduction estimator (RARE) fourth-order cumulants (FOC) spatial spectrum angle resolution probability unexpected modeling errors
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