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Comparison of the Length of Stay and Medical Expenditures among Japanese Hospitals for Type 2 Diabetes Treatments: The Box-Cox Transformation Model under Heteroscedasticity 被引量:2
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作者 Kazumitsu Nawata Koichi Kawabuchi 《Health》 CAS 2016年第1期49-63,共15页
In this paper, we analyzed length of stay (LOS) in hospitals and medical expenditures for type 2 diabetes patients. LOS was analyzed by the power Box-Cox transformation model when variances differed among hospitals. W... In this paper, we analyzed length of stay (LOS) in hospitals and medical expenditures for type 2 diabetes patients. LOS was analyzed by the power Box-Cox transformation model when variances differed among hospitals. We proposed a new test and consistent estimator. We rejected the ho-moscedasticity of variances among hospitals, and then analyzed the LOS of 12,666 type 2 diabetes patients hospitalized for regular medical treatments collected from 60 general hospitals in Japan. The variables found to affect LOS were age, number of comorbidities and complications, introduced by another hospital, one-week hospitalization, 2010 revision, specific-hospitalization-period (SHP), and principal diseases E11.5, E11.6 and E11.7. There were surprisingly large differences in ALOS among hospitals even after eliminating the influence of characteristics and conditions of patients. We then analyzed daily medical expenditure (DME) by the ordinary least squares methods. The variables that affected DME were LOS, number of comorbidities and complications, acute hospitalization, hospital’s own outpatient, season, introduced by another hospital, one-week hospitalization, 2010 revision, SHP, time trend, and principal diseases E11.2, E11.4 and E117. The DME did not decrease after the SHP. After eliminating the influences of characteristics and conditions of patients, the differences among hospitals were relatively small, 12% of the overall average. LOS is the main determinant of medical expenditures, and new incentives to reduce LOS are needed to control Japanese medical expenditures. Since at least 99% of patients require medical care after leaving the hospital, systems that take proper care of patients for long periods of time after hospitalization are absolutely necessary for efficient treatment of diabetes. 展开更多
关键词 Type 2 Diabetes Medical Expenditure length of Hospital Stay Cox-Box transformation HETEROSCEDASTICITY
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An Econometric Analysis of Hospital Length of Stay for Cataract Operations in Japan by the Box-Cox Transformation Model and Hausman Tests: Evaluation of the 2010 Revision of the Medical Payment System
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作者 Kazumitsu Nawata Koichi Kawabuchi 《Open Journal of Applied Sciences》 2015年第9期559-570,共12页
The Japanese medical costs for cataract treatments reached 270 billion yen in fiscal year 2012. Since the length of stay (LOS) in hospital is much longer than other major countries, controlling the medical costs by re... The Japanese medical costs for cataract treatments reached 270 billion yen in fiscal year 2012. Since the length of stay (LOS) in hospital is much longer than other major countries, controlling the medical costs by reducing LOS becomes an important issue in Japan. In this paper, we evaluated the effects of the 2010 revision of the Japanese medical payment system (DPC/PDPS) on LOS for cataract operations. The Box-Cox transformation model, Nawata’s estimators and Hausman tests were used in the analysis. To evaluate the effects, we analyzed a dataset obtained from 34 DPC hospitals (Hp1-34) where one-eye cataract operations were performed both before (April 2008-March 2010) and after (April 2010-March 2012) the 2010 revision and there were more than 500 patients. The dataset contained information from 32,593 patients. We did not admit the effect of the 2010 revision in this study, and there were large differences LOS among hospitals, even after removing the influences of factors such as patient characteristics and types of principal diseases. 展开更多
关键词 Diagnosis Procedure Combination (DPC) CATARACT length of Stay (LOS) Box-Cox transformATION Model
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基于正态变换的变样本容量Shewhart比例控制图设计
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作者 周思阳 张莹 柯楚贤 《计算机集成制造系统》 EI CSCD 北大核心 2024年第2期610-622,共13页
为了提高Shewhart型比例控制图的监控效率,将其与变样本容量策略结合,提出一种新的比例控制图(VSS Shewhart-RZ*控制图)来监控二元正态变量之比。基于正态变换方法设计了新的比例统计量Z*,以消除样本容量变化对比例控制图设计及使用的... 为了提高Shewhart型比例控制图的监控效率,将其与变样本容量策略结合,提出一种新的比例控制图(VSS Shewhart-RZ*控制图)来监控二元正态变量之比。基于正态变换方法设计了新的比例统计量Z*,以消除样本容量变化对比例控制图设计及使用的不利影响。采用马尔科夫链方法计算了该控制图的平均运行长度和平均样本容量,给出该控制图的参数优化算法。通过仿真分析研究了该控制图的统计性能,并与Shewhart比例控制图进行比较,结果表明VSS Shewhart-RZ*控制图的性能明显优于传统固定样本容量Shewhart比例控制图。 展开更多
关键词 变样本容量 比例分布 平均运行链长 正态变换
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分段拼接坐标系在越岭公路中的局限性分析
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作者 张程虹 《科技资讯》 2024年第5期119-121,共3页
在山区越岭公路工程中,分段投影拼接坐标系与隧道独立坐标系在隧道两端出现了控制点边长差距较大的问题。根据地面边长归化到参考椭球面的长度变形分析拼接坐标系在越岭公路的总体变形,并与以隧道工程平均高程为抵偿投影面的隧道独立坐... 在山区越岭公路工程中,分段投影拼接坐标系与隧道独立坐标系在隧道两端出现了控制点边长差距较大的问题。根据地面边长归化到参考椭球面的长度变形分析拼接坐标系在越岭公路的总体变形,并与以隧道工程平均高程为抵偿投影面的隧道独立坐标系比较,得到分段拼接坐标系与隧道独立坐标系的不一致性。以工程实例总结出分段拼接坐标系在山区公路遇到隧道工程时,其边长变形的局限性,以及在应用拼接坐标系的注意项及其对隧道贯通的影响。 展开更多
关键词 坐标系 坐标转换 控制网 投影面 长度变形 局限性
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The Coherence Cube Computing Method with Self-adaptive Time Window Based on Wavelet Transform 被引量:4
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作者 LI Ying-qi CHE Xiang-jiu 《Computer Aided Drafting,Design and Manufacturing》 2014年第2期10-14,共5页
The coherence cube technology has become an important technology for the seismic attribute interpretation, which extracts the discontinuities of the events through analyzing the similarities of adjacent seismic channe... The coherence cube technology has become an important technology for the seismic attribute interpretation, which extracts the discontinuities of the events through analyzing the similarities of adjacent seismic channels to identify the fault form. The coherence cube technology which uses constant time window lengths can not balance the shallow layers and the deep layers, because the frequency band of seismic data varies with time. When analyzing the shallow layers, the time window will crossover a lot of events, which will lead to weak focusing ability and failure to delineate the details. While the time window will not be long enough for analyzing deep layers, which will lead to low accuracy because the coherences near the zero points of the events are heavily influenced by noise. For solving the problem, we should make a research on the coherence cube technology with self-adaptive time window. This paper determines the sample points&#39; time window lengths in real time by computing the instantaneous frequency bands with Wavelet Transformation, which gives a coherence computing method with the self-adaptive time window lengths. The result shows that the coherence cube technology with self-adaptive time window based on Wavelet Transformation improves the accuracy of fault identification, and supresses the noise effectively. The method combines the advantages of long time window method and short time window method. 展开更多
关键词 coherence cube time window length Wavelet transformation seismic attribute
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Optimum Optical Length of the Gas Cell Used for Monitoring Gas-In-Oil with FTIR 被引量:1
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作者 刘先勇 黄风雷 +1 位作者 王霞 周方洁 《Journal of Beijing Institute of Technology》 EI CAS 2003年第1期59-63,共5页
Dedicated experiments are designed to collect the infrared spectra of dissolved gas-in-oil of power transformers. Spectra of diagnostic gases are collected by 3 different laboratorial FTIR spectrometers using 3 differ... Dedicated experiments are designed to collect the infrared spectra of dissolved gas-in-oil of power transformers. Spectra of diagnostic gases are collected by 3 different laboratorial FTIR spectrometers using 3 different gas cells with various sets of equipment parameters. A formula is deduced to calculate the shortest optical length to detect a specific concentration according to measurements on gases with known concentrations near to the minimum detection limit. Collected spectra and calculated results suggested that the optimum optical length of the gas cell should be 150 mm to realize on-line monitoring of diagnostic gases within the required concentration range. At the end, an economic novel design of the gas cell is proposed based on the optimum length. 展开更多
关键词 FTIR gas cell power transformer DGA optical length dissolved gas-in-oil
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Estimation of structural modal parameters by fourier transform with an optimal window 被引量:1
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作者 朱宏平 万信华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第5期595-598,共4页
关键词 快速傅立叶变换 时频分析 时间序列 光谱分析
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Evaluation of Length of Hospital Stay Joining Educational Programs for Type 2 Diabetes Mellitus Patients: Can We Control Medical Costs in Japan? 被引量:4
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作者 Kazumitsu Nawata Koichi Kawabuchi 《Health》 2015年第2期256-269,共14页
Diabetes has become a growing concern in Japan, both medically and financially. The medical cost of diabetes was estimated at 1215 billion yen for fiscal year 2011. We analyzed the length of stay (LOS) in a hospital f... Diabetes has become a growing concern in Japan, both medically and financially. The medical cost of diabetes was estimated at 1215 billion yen for fiscal year 2011. We analyzed the length of stay (LOS) in a hospital for type 2 diabetes mellitus patients who participated in educational programs to determine factors affecting LOS. Data on 991 patients obtained from 28 Red Cross hospitals in 2008 were used. For the analysis, we used the Box-Cox transformation model and Hausman test. The results revealed that patients aged 75 years and above and those with comorbidities and complications were prone to longer LOS. The analysis also revealed significant differences in LOS across the hospitals, even after controlling for patient characteristics. Finally, we applied the least squares method to determine the effects of hospital and regional factors and revealed that patients’ LOS was affected by the region’s average LOS. Regional corporations and networks appeared to be important in improving educational programs. 展开更多
关键词 Medical COST DIABETES Type 2 DIABETES MELLITUS PATIENTS length of Stay (LOS) EDUCATIONAL Program Box-Cox transformation Model
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Very Low Bit-Rate Video Coding by Combining H.264/AVC Standard and 2-D Discrete Wavelet Transform
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作者 Ali Aghagolzadeh Saeed Meshgini +1 位作者 Mehdi Nooshyar Mehdi Aghagolzadeh 《Wireless Sensor Network》 2010年第4期328-336,共9页
In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is a... In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is applied on each video frame independently to extract the low frequency components for each frame and then the low frequency parts of all frames are coded using H.264/AVC codec. On the other hand, the high frequency parts of the video frames are coded by Run Length Coding algorithm, after applying a threshold to neglect the low value coefficients. Experiments show that our proposed method can achieve better rate-distortion performance at very low bit-rate applications below 16 kbits/s compared to applying H.264/AVC standard directly to all frames. Applications of our proposed video coding technique include video telephony, video-conferencing, transmitting or receiving video over half-rate traffic channels of GSM networks. 展开更多
关键词 Video CODING H.264/AVC STANDARD RUN length CODING Two-Dimensional WAVELET transform
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基于坐标变换的强间断问题伪弧长算法
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作者 陈泽平 王晨涛 +1 位作者 李坤 马天宝 《兵器装备工程学报》 CAS CSCD 北大核心 2023年第4期68-76,共9页
针对爆炸冲击波数值模拟中经常要面临的强间断奇异性问题,在一维或多维空间中引入弧长参数,通过添加一个约束方程,致使原网格自适应移动变形而能够在强间断区域分布较多的网格点,以此提高大梯度物理量捕捉的分辨率。针对非均匀变形物理... 针对爆炸冲击波数值模拟中经常要面临的强间断奇异性问题,在一维或多维空间中引入弧长参数,通过添加一个约束方程,致使原网格自适应移动变形而能够在强间断区域分布较多的网格点,以此提高大梯度物理量捕捉的分辨率。针对非均匀变形物理空间中格式构造困难的问题,提出了坐标变换,将物理空间中的控制方程映射至均匀正交的弧长计算空间。基于MUSCL格式编写了伪弧长算法相应的一维、二维程序,并对其开展人为解方法验证。将伪弧长算法(PALM)的数值结果同有限体积法进行比较,经过误差分析,验证了伪弧长算法在间断附近具有较高的分辨率。 展开更多
关键词 爆炸冲击波 数值模拟 伪弧长算法 坐标变换 精度验证
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Lorentz Transform in Multi-Dimensional Space
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作者 I. A. Urusovskii 《Journal of Modern Physics》 2012年第11期1749-1756,共8页
It is shown that in Euclidean space with any number of spatial dimensions more than three, the Lorentz transform holds true if the proper time of each elementary particle is proportional to the length of its path in t... It is shown that in Euclidean space with any number of spatial dimensions more than three, the Lorentz transform holds true if the proper time of each elementary particle is proportional to the length of its path in the extra-dimensional subspace, and all elementary particles move at the speed of light in the complete space. The six-dimensional treatment of the Coulomb force of interaction between two charges is given. The electric force is due to the motion of charges in the extra-dimensional subspace and is equal to the corresponding Lorentz force. 展开更多
关键词 LORENTZ transform Euclidean Multi-Dimensional Space COMPTON Wave length De BROGLIE Waves SPIN and Isotopic SPIN HEISENBERG Uncertainty CPT Symmetry COULOMB Force
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基于“区域-时间-长度算法”的傅里叶变换分析华北地区6级以上地震活动性变化规律
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作者 贺劲松 卫超 《山西地震》 2023年第4期13-18,共6页
“区域-时间-长度算法”(Region-Time-Length algorithm)是描述某地区地震活动水平与其本底地震活动水平偏离程度的一种研究方法,在国外多个强震中前得到应用检验。本文利用这一方法对1970年以来华北地区8次有较大影响的6.0级以上强震... “区域-时间-长度算法”(Region-Time-Length algorithm)是描述某地区地震活动水平与其本底地震活动水平偏离程度的一种研究方法,在国外多个强震中前得到应用检验。本文利用这一方法对1970年以来华北地区8次有较大影响的6.0级以上强震前的地震活动变化进行检验,全部出现地震活动增强的现象,异常持续时间在5~24个月,异常幅度偏离背景值幅度较大,异常现象较明显,为华北地区区域地震活动性异常指标研究提供新的参考。同时运用傅里叶变换,将得到的时域值转换为频域值,进一步提升这种方法的可操作性。通过研究发现,其在变化过程中持续上升的量值很难把控,异常达到具体阈值时还需做进一步的分析研究。 展开更多
关键词 地震活动性 区域-时间-长度算法 傅里叶变换 华北中强地震
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基于PADC-PCNN与平稳小波变换多焦距绿色植株图像融合算法
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作者 李嘉豪 瞿宏俊 +2 位作者 高名喆 仝德之 郭亚 《智慧农业(中英文)》 CSCD 2023年第3期121-131,共11页
[目的/意义]构建绿色植株三维点云模型需大量清晰图像,受镜头景深限制,在采集大纵深植株图像时图像会部分失焦,导致出现边缘模糊、纹理细节丢失等问题,现有的处理算法难以兼顾处理质量和处理速度。本研究目的是提出一种新型算法,提高融... [目的/意义]构建绿色植株三维点云模型需大量清晰图像,受镜头景深限制,在采集大纵深植株图像时图像会部分失焦,导致出现边缘模糊、纹理细节丢失等问题,现有的处理算法难以兼顾处理质量和处理速度。本研究目的是提出一种新型算法,提高融合图像质量问题的同时兼顾处理速度。[方法]提出了一种基于非下采样剪切波变换(Non-Subsampled Shearlet Transform,NSST)的参数自适应双通道脉冲耦合神经网络(Parameter Adaptation Dual Channel Pulse Coupled Neural Network,PADC-PCNN)与平稳小波变换(Stationary Wavelet Transform,SWT)的植株图像融合方法。首先对植株的RGB图像进行通道分离,针对含纹理细节等特征较多的G通道进行NSST分解,低频子带使用梯度能量融合规则,高频子带使用PADC-PCNN融合规则;对轮廓信息和背景信息多的R、B通道,采用速度快且具备平移不变性的平稳小波变换,用以抑制伪Gibbs效应。自建了480幅图像共8组数据,以光照环境、距离和植株颜色为变量,同时采集不同焦距图像验证算法性能。[结果和讨论]基于PADCPCNN-SWT算法与常用的快速导向滤波算法(Fast Guided Filter,FGF)、随机游走算法(Random Walk,RW)、非下采样剪切波变换的脉冲耦合神经网络算法(Nonsubsampled Shearlet Transform based Pulse-Coupled Neural Network,NSST-PCNN)、平稳小波变换算法(Stationary Wavelet Transform,SWT)和非下采样剪切波变换的参数自适应双通道脉冲耦合神经网络(Nonsubsampled Shearlet Transform based Parameter-Adaptive Dual-Channel Pulse-Coupled Neural Network,NSST-PADC)等五种算法相比,在清晰度上比前四种算法分别提高了5.6%、8.1%、6.1%和17.6%,在空间频率上比前四种算法分别提高了2.9%、4.8%、7.1%和15.9%,而相较于融合效果最好的NSSTPADC算法在处理速度方面平均提升200.0%,同时调焦范围约6 mm。[结论]本研究提出的基于PADC-PCNNSWT多焦距图像融合算法实现了在保障融合质量的同时,提高了融合图像的效率,为搭建绿色植株三维点云模型提供高质量数据的同时节省了时间。 展开更多
关键词 多焦距 图像融合 平稳小波变换 参数自适应 脉冲耦合 神经网络
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大采长工作面高承压水底板注浆改造技术研究 被引量:2
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作者 段李宏 《矿业安全与环保》 CAS 北大核心 2023年第4期110-115,共6页
为解决陈四楼煤矿大采长工作面高承压水区域底板水害治理难题,在矿井典型2517大采长工作面采用底板注浆改造技术解放受底板太原组灰岩水威胁的煤层。通过资料调研和数据计算,选取改造层位并进行钻孔设计,基于底板注浆改造钻孔的涌水量... 为解决陈四楼煤矿大采长工作面高承压水区域底板水害治理难题,在矿井典型2517大采长工作面采用底板注浆改造技术解放受底板太原组灰岩水威胁的煤层。通过资料调研和数据计算,选取改造层位并进行钻孔设计,基于底板注浆改造钻孔的涌水量和注浆量数据,对各含水层富水性、注浆量、主要可注裂隙、不同级别充水裂隙注浆材料消耗及平均单孔耗浆量规律进行对比分析。结果表明,含水层富水区主要受裂隙、断层和褶皱等构造的影响,L_(10)灰岩和L_(8)灰岩含水层富水性强,分布较均匀,连通性较好,其含水层以中小型和大型裂隙为主且中小型裂隙较多;工作面平均单孔耗浆量约是充水裂隙涌水量的3.4倍。3次物探结果显示,底板注浆改造效果显著,基本解决了陈四楼煤矿高承压水工作面底板突水问题,可为其他矿区矿井水害治理提供借鉴。 展开更多
关键词 大采长工作面 高承压水 灰岩含水层 涌水量 底板注浆改造
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基于第二类椭圆积分的子午线弧长公式变换及解算 被引量:13
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作者 过家春 赵秀侠 +2 位作者 徐丽 田劲松 高飞 《大地测量与地球动力学》 CSCD 北大核心 2011年第4期94-98,共5页
通过推导,将子午线弧长公式变换为基于第二类椭圆积分的两种形式:"形式Ⅰ"将子午线弧长公式表达为一个有理函数和第二类椭圆积分之和,建立了以大地纬度B为自变量的子午线弧长公式与第二类椭圆积分之间的关系;"形式Ⅱ&qu... 通过推导,将子午线弧长公式变换为基于第二类椭圆积分的两种形式:"形式Ⅰ"将子午线弧长公式表达为一个有理函数和第二类椭圆积分之和,建立了以大地纬度B为自变量的子午线弧长公式与第二类椭圆积分之间的关系;"形式Ⅱ"给出了以归化纬度μ为自变量、直接利用第二类椭圆积分计算子午线弧长的公式。利用此两种形式的子午线弧长公式,在Matlab中编写程序,调用第二类椭圆积分函数EllipticE(x,k)计算子午线弧长,精度和计算效率均优于经典算法。对CGCS2000所采用的地球椭球子午线弧长的计算表明,此两种形式的子午线弧长公式建立了子午线弧长公式与第二类椭圆积分的关系,结构简洁,易于展开,一定程度上完善了子午线弧长理论,且便于手工计算及计算机程序实现。 展开更多
关键词 子午线弧长 公式变换 椭圆积分 大地纬度 归化纬度
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茧丝纤度序列长度的变换方法 被引量:8
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作者 费万春 罗军 +1 位作者 黎霞 白伦 《苏州大学学报(工科版)》 CAS 2003年第2期17-23,共7页
对于有限长度的连续变化茧丝纤度序列,为了对其进行模拟生成及自回归预测,本文给出了两种序列长度归一化的变换方法,并对茧丝纤度序列进行变换试验,分析变换误差。变换方法可用于有限长度时间序列的预处理。
关键词 茧丝纤度 序列长度 变换方法 时间序列分析 制丝
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大跨自锚式悬索桥吊索张拉与体系转换技术研究 被引量:18
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作者 袁明 王同民 黄晓航 《世界桥梁》 北大核心 2015年第3期15-19,共5页
为快速实现大跨自锚式悬索桥体系转换,以(160+406+160)m的双塔三跨自锚式悬索桥——桃花峪黄河大桥为背景,研究以吊索引出量控制为主、索力控制为辅的吊索张拉与体系转换技术。建立实桥有限元模型,计算吊索无应力长度,定义索头引伸出下... 为快速实现大跨自锚式悬索桥体系转换,以(160+406+160)m的双塔三跨自锚式悬索桥——桃花峪黄河大桥为背景,研究以吊索引出量控制为主、索力控制为辅的吊索张拉与体系转换技术。建立实桥有限元模型,计算吊索无应力长度,定义索头引伸出下锚垫板的长度值为引出量;采用引出量控制,从塔根向远离桥塔方向对称张拉吊索(每次8组),跨中几组吊索采取纵向相邻2组同时装千斤顶,在n号吊索张拉的同时,预拉(n+1)号吊索;进行主桥缩尺模型试验,对该方案进行验证及细节优化。研究结果及实际工程表明:采用该体系转换技术方案,主缆与吊索张力、临时墩反力、主梁应力计算值等均满足要求;缩尺模型实测应力、位移与有限元计算值吻合;主梁线形质量好,吊索索力精度高,快速实现了体系转换。 展开更多
关键词 自锚式悬索桥 吊索张拉 引出量 无应力长度 体系转换 长度控制 施工技术
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Ronchi光栅Talbot效应长焦距测量的准确度极限研究 被引量:10
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作者 孙琛 沈亦兵 +2 位作者 白剑 侯西云 杨国光 《光子学报》 EI CAS CSCD 北大核心 2004年第10期1214-1217,共4页
针对基于Ronchi光栅Talbot效应的长焦距测量方法 ,分析了利用傅里叶变换求取莫尔条纹角度的准确度限制 ,提出了通过傅里叶变换的多次迭代逼近来提高角度计量准确度 ,从而提高长焦距测量准确度的方法 。
关键词 焦距测量 傅里叶变换 莫尔条纹
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肌动蛋白基因在棉花纤维中的作用研究 被引量:8
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作者 范小平 范博红 +2 位作者 李学宝 杨维才 徐子勤 《华北农学报》 CSCD 北大核心 2008年第5期73-75,共3页
运用农杆菌介导法将肌动蛋白RNAi表达载体PBI121-GhACT1转化棉花,经胚胎发生获得再生植株。非转化组培再生苗作为对照。以NPTII制备探针,Southern杂交结果表明,获得8个独立遗传转化系,其中3个系有2个拷贝插入;其余6个系为多拷贝。显微... 运用农杆菌介导法将肌动蛋白RNAi表达载体PBI121-GhACT1转化棉花,经胚胎发生获得再生植株。非转化组培再生苗作为对照。以NPTII制备探针,Southern杂交结果表明,获得8个独立遗传转化系,其中3个系有2个拷贝插入;其余6个系为多拷贝。显微镜下观察开花后第5天的幼胚珠孔端,对照纤维长度约是RNAi载体转基因的3-5倍。成熟后绒长F测验结果表明,RNAi载体转化株与对照差异显著,RNAi转基因植株的绒长显著短于对照。说明GhACT1基因对纤维有延缓和抑制作用,并且主要作用于纤维发育早期。 展开更多
关键词 RNAi表达载体 肌动蛋白 转化 绒长
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Z变换和Δ变换的有限字长特性研究 被引量:11
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作者 陈宗基 高金源 张建贵 《自动化学报》 EI CSCD 北大核心 1992年第6期662-670,共9页
计算机的有限字长对数字控制器的实现有重要影响。本文介绍了△变换及其δ算子的数字控制器的实现方法,证明了δ算子实现方法在系数有限字长表示、运算中对舍入及截尾误差的影响;有限字长非线性因素对极限环振荡的影响等方面,都优于常用... 计算机的有限字长对数字控制器的实现有重要影响。本文介绍了△变换及其δ算子的数字控制器的实现方法,证明了δ算子实现方法在系数有限字长表示、运算中对舍入及截尾误差的影响;有限字长非线性因素对极限环振荡的影响等方面,都优于常用的z变换及其q算子的数字控制器实现方法。本文还提供了某型飞机的数字控制器在z变换和△变换下的不同有限字长特性的数字仿真。 展开更多
关键词 有限字长 Z变换 △变换 数字控制器
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