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统计学计量资料(均数)的比较方法
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《世界今日医学杂志》 2005年第4期259-259,共1页
Dunnett t检验:当多个试验组与同一个对照组比较,资料呈正态分布且方差齐时,采用此检验方法。如果方差不齐或非正态分布时,可用多个试验组与一个对照组比较的秩和检验。
关键词 计量资料(均数) 比较方法 统计学 Dunnett 正态分布 方差不齐 检验方法 秩和检验 对照组
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统计学计量资料(均数)的比较方法
2
《世界今日医学杂志》 2005年第5期310-310,共1页
Dunnett t检验:当多个试验组与同一个对照组比较,资料呈正态分布且方差齐时,采用此检验方法。如果方差不齐或非正态分布时,可用多个试验组与一个对照组比较的秩和检验。
关键词 计量资料(均数) 比较方法 统计学 Dunnett 正态分布 方差不齐 检验方法 秩和检验 对照组 T检验
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统计学计量资料(均数)的比较方法
3
《世界今日医学杂志》 2005年第3期206-206,共1页
Dunnett t检验:当多个试验组与同一个对照组比较,资料呈正态分布且方差齐时,采用此检验方法。如果方差不齐或非正态分布时,可用多个试验组与一个对照组比较的秩和检验。
关键词 计量资料(均数) 比较方法 统计学 Dunnett 正态分布 方差不齐 检验方法 秩和检验 对照组
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统计学计量资料(均数)的比较方法
4
《世界今日医学杂志》 2007年第3期184-184,共1页
Dunnettt检验:当多个试验组与同一个对照组比较,资料呈正态分布且方差齐时,采用此检验方法。如果方差不齐或非正态分布时,可用多个试验组与一个对照组比较的秩和检验。
关键词 计量资料(均数) 比较方法 统计学 Dunnett 正态分布 方差不齐 秩和检验 对照组
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统计学计量资料(均数)的比较方法
5
《世界今日医学杂志》 2006年第3期160-160,共1页
Dunnett t检验:当多个试验组与同一个对照组比较,资料呈正态分布且方差齐时,采用此检验方法。如果方差不齐或非正态分布时,可用多个试验组与一个对照组比较的秩和检验。
关键词 计量资料(均数) 比较方法 统计学 Dunnett 正态分布 方差不齐 秩和检验 对照组
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统计学计量资料(均数)的比较方法
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《世界今日医学杂志》 2006年第2期78-78,共1页
Dunnett t检验:当多个试验组与同一个对照组比较,资料呈正态分布且方差齐时,采用此检验方法。如果方差不齐或非正态分布时,可用多个试验组与一个对照组比较的秩和检验。
关键词 计量资料(均数) 比较方法 统计学 正态分布 方差不齐 检验方法 秩和检验 对照组 T检验
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统计学计量资料(均数)的比较方法
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《世界今日医学杂志》 2003年第3期189-189,共1页
关键词 统计学计量资料 (均数) 比较方法 Dunnett T检验
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统计学计量资料(均数)的比较方法
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《世界今日医学杂志》 2003年第2期102-102,共1页
关键词 统计学 计量资料(均数) 比较方法 检验
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Estimating runoff coefficient for quantity assessment of roof rainwater harvesting system 被引量:1
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作者 张炜 李思敏 唐锋兵 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期220-224,共5页
In order to accurately estimate the runoff coefficient for the quantity assessment of the roof rainwater harvesting system RRHS great differences in the value of event runoff coefficient ψERC were observed by field m... In order to accurately estimate the runoff coefficient for the quantity assessment of the roof rainwater harvesting system RRHS great differences in the value of event runoff coefficient ψERC were observed by field monitoring under different roof types roof slope and material and diverse rainfall distributions rainfall depth and intensity in three years 2010 to 2012 in Handan Hebei China.The results indicate that the distribution of ψERC is more highly correlated with the event rainfall depth than other factors. The relationship between ψERC and the rainfall depth can be well represented by the piecewise linear function.Further based on the daily rainfall data over the period from 1960 to 2008 the value of the annual runoff coefficient ψARC is calculated. Although the total rainfall depth in each year is different ψARC in Handan can be considered as a constant 0.62 approximately. The results can be used for the quantity assessment and performance analysis of the RRHS. 展开更多
关键词 roof rainwater harvesting system event runoff coefficient annual runoff coefficient rainfall depth
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A Number Theoretic Function and Its Mean Value Computation 被引量:1
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作者 李海龙 杨倩丽 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期53-56,共4页
Let p be a prime, n be any positiv e integer, α(n,p) denotes the power of p in the factorization of n! . In this paper, we give an exact computing formula of the mean value ∑ n<Nα(n,p).
关键词 number theoretic function mean value computing formula
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Strategic equilibrium price analysis and numerical simulation of preponderant high-tech metal mineral resources 被引量:3
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作者 钟美瑞 谌杰宇 +1 位作者 朱学红 黄健柏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3153-3160,共8页
Based on exploitation compensation value system of preponderant high-tech metal mineral resources and distortion of pricing mechanism, social utility function was constructed to modify decision utility function of dev... Based on exploitation compensation value system of preponderant high-tech metal mineral resources and distortion of pricing mechanism, social utility function was constructed to modify decision utility function of developers, and was extended to Stackelberg production decision model of preponderant high-tech metal mineral resources development. Analyzing the influences on market monopoly, output and price decision-making exerted by altruistic preferences, inequity aversion and sequential reciprocity fairness belief equilibrium, game fairness equilibrium which is significant in experimental economics can be obtained and verified by numerical simulation. In process of strategic pricing, method that uses the variation of producer surplus to measure strategic value from psychological preferences was proposed for the first time and technical support to improve exploitation compensation value system of preponderant metal mineral resources was available. 展开更多
关键词 METAL high-tech mineral mineral resources equilibrium price numerical simulation
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Seismic data analysis based on spatial subsets 被引量:2
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作者 蔡希玲 刘学伟 +2 位作者 李虹 钱宇明 吕英梅 《Applied Geophysics》 SCIE CSCD 2009年第4期384-392,395,共10页
There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from ... There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from common shot gathers or other datasets located at certain points or along lines. We propose a novel method in this paper to observe seismic data on time slices from spatial subsets. The composition of a spatial subset and the unique character of orthogonal or oblique subsets are described and pre-stack subsets are shown by 3D visualization. In seismic data processing, spatial subsets can be used for the following aspects: (1) to check the trace distribution uniformity and regularity; (2) to observe the main features of ground-roll and linear noise; (3) to find abnormal traces from slices of datasets; and (4) to QC the results of pre-stack noise attenuation. The field data application shows that seismic data analysis in spatial subsets is an effective method that may lead to a better discrimination among various wavefields and help us obtain more information. 展开更多
关键词 spatial subset 3D visualization high density sampling noise attenuation data analysis
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Construction of a database of average cross-sections in Chinese proximal femurs
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作者 马如宇 王冬梅 +2 位作者 薛文东 戴尅戎 王成焘 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期191-194,共4页
The process of constructing a database of average cross-sections in Chinese proximal femurs is described. The main goal of creating the database is for designing hip stems for Chinese patients. Methods for constructin... The process of constructing a database of average cross-sections in Chinese proximal femurs is described. The main goal of creating the database is for designing hip stems for Chinese patients. Methods for constructing the database are introduced. According to some existing software and programs developed by the authors, a database of average cross-sections in Chinese proximal femurs was built based on CT images of eighty femur-specimens. 3-D shape of a patient's proximal femurs can be reconstructed according to the database and X-ray radiographs. Theoretical analyses and results of clinical application indicate that the database can be used to design hip stems for Chinese patients. 展开更多
关键词 Computerized tomography Database systems Hip prostheses X ray films
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Numerical Simulation of the Influence of Mean Sea Level Rise on Typhoon Storm Surge in the East China Sea 被引量:3
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作者 高志刚 韩树宗 +2 位作者 刘克修 郑运霞 于华明 《Marine Science Bulletin》 CAS 2008年第2期36-49,共14页
In this paper, ECOMSED (Estuarine Coastal Ocean Model with sediment transport) model is employed to simulate storm surge process caused by typhoon passing across East China Sea in nearly years. Capability of ECOMSED... In this paper, ECOMSED (Estuarine Coastal Ocean Model with sediment transport) model is employed to simulate storm surge process caused by typhoon passing across East China Sea in nearly years. Capability of ECOMSED to simulate storm surge is validated by comparing model result with observed data. Sensitivity experiments are designed to study the influence of sea level rise on typhoon storm surge. Numerical experiment shows that influence of mean sea level rise on typhoon storm surge is non-uniform spatially and changes as typhoon process differs. Maybe fixed boundary method would weaken the influence of mean sea level rise on storm surge, and free boundary method is suggested for the succeeding study. 展开更多
关键词 Storm surge simulation ECOMSED model East China Sea sea level rise
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Inhomogeneity of density and mechanical properties of A357 aluminum alloy backward extruded in semi-solid state 被引量:6
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作者 杜之明 陈刚 +1 位作者 程远胜 谢水生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第10期2285-2293,共9页
The inhomogeneity of density and mechanical properties of A357 aluminum alloy in the semi-solid state were investigated.Numerical simulation and backward extrusion were adopted to study the preparation of cup shells.T... The inhomogeneity of density and mechanical properties of A357 aluminum alloy in the semi-solid state were investigated.Numerical simulation and backward extrusion were adopted to study the preparation of cup shells.The results show that the relative density of the wall is the lowest in samples,and that of the base is the highest.With increasing the billet height,more time is needed for relative density of the corner to reach the maximum value,and the relative densities in every region improve evidently with increasing the pressure.The tensile stress was simulated to be the largest at the corner,and the hot tearings were forecasted to mainly appear at the corner too.By employing proper billet height and pressure,the extruded samples consisted of fine and uniform microstructures,and can obtain excellent mechanical properties and Brinell hardness. 展开更多
关键词 A357 aluminum alloy INHOMOGENEITY semi-solid state backward extrusion numerical simulation
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Dimension-down iterative algorithm for the mixed transportation network design problem
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作者 陈群 姚加林 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期236-239,共4页
An optimal dimension-down iterative algorithm (DDIA) is proposed for solving a mixed (continuous/ discrete) transportation network design problem (MNDP), which is generally expressed as a mathematical programmin... An optimal dimension-down iterative algorithm (DDIA) is proposed for solving a mixed (continuous/ discrete) transportation network design problem (MNDP), which is generally expressed as a mathematical programming with equilibrium constraints (MPEC). The upper level of the MNDP aims to optimize the network performance via both the expansion of existing links and the addition of new candidate links, whereas the lower level is a traditional Wardrop user equilibrium (UE) model. The idea of the proposed DDIA is to reduce the dimensions of the problem. A group of variables (discrete/continuous) are fixed to altemately optimize another group of variables (continuous/discrete). Some continuous network design problems (CNDPs) and discrete network design problems (DNDPs) are solved repeatedly until the optimal solution is obtained. A numerical example is given to demonstrate the efficiency of the proposed algorithm. 展开更多
关键词 mixed network design problem (MNDP) dimension-down iterative algorithm (DDIA) mathematical programming with equilibrium constraint (MPEC)
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Qo E-based resource allocation protocols in cognitive OFDMA network with hybrid model
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作者 鲍煦 张雷 宋铁成 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期1-4,共4页
A resource allocation protocol is presented in an orthogonal frequency division multiple access (OFDMA) cognitive radio (CR) network with a hybrid model which combines overlay and underlay models. Without disrupti... A resource allocation protocol is presented in an orthogonal frequency division multiple access (OFDMA) cognitive radio (CR) network with a hybrid model which combines overlay and underlay models. Without disrupting the primary user (PU) transmissions, the overlay model allows the secondary user (SU) to utilize opportunistically the idle sub-channels; the underlay model allows the SU to occupy the same sub-channels with PU. The proposed protocols are designed for maximizing the quality of experience (QoE) of CR users and switching dynamically between the overlay and underlay models. QoE is measured by the mean opinion score (MOS) rather than simply fulfilling the physical and medium access control (MAC) layer requirements. The simulations considering the file transfer and video stream services show that the proposed resource allocation strategy is spectrum efficient. 展开更多
关键词 resource allocation cognitive radio network orthogonal frequency division multiple access (OFDMA) quality of user experience mean opinion score
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Parameter estimation methods in generalized weighted functional mean combining forecasting model
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作者 万玉成 盛昭瀚 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期117-121,共5页
A kind of combining forecasting model based on the generalized weighted functional mean is proposed. Two kinds of parameter estimation methods with its weighting coefficients using the algorithm of quadratic programmi... A kind of combining forecasting model based on the generalized weighted functional mean is proposed. Two kinds of parameter estimation methods with its weighting coefficients using the algorithm of quadratic programming are given. The efficiencies of this combining forecasting model and the comparison of the two kinds of parameter estimation methods are demonstrated with an example. A conclusion is obtained, which is useful for the correct application of the above methods. 展开更多
关键词 Forecasting Quadratic programming
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Effect of local thermal sensation on whole-body thermal sensation under stable non-uniform environment
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作者 丁千茹 金权 +1 位作者 李祥立 端木琳 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期238-242,共5页
To reveal the principles of human thermal responses and find out the effects of body parts on whole-body thermal sensation,through a subjective survey,experimental investigations on human responses are carried out whe... To reveal the principles of human thermal responses and find out the effects of body parts on whole-body thermal sensation,through a subjective survey,experimental investigations on human responses are carried out when a single body part is thermally stimulated.Cooling airflow is sent to seven body parts,respectively.Totally 94 samples are tested.To eliminate the obvious multicollinearity of thermal sensation among different body parts,the principal component regression approach is adopted to obtain the principal components for the body parts under different experimental conditions.Through regression and analysis of principal components,the weighting factors of the seven body parts are obtained.A predictive model on whole-body thermal sensation is obtained based on the weighting factors.The results show that the different characteristics of trunk and limbs are clearly seen.The weighting factors of local thermal sensation are integrated values,and there is little difference among values of different body parts. 展开更多
关键词 local thermal sensation whole-body thermal sensation non-uniform environment weighting factor
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A New Class of Biased Linear Estimators in Deficient-rank Linear Models 被引量:1
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作者 归庆明 段清堂 +1 位作者 周巧云 郭建锋 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期71-78,共8页
In this paper, we define a new class of biased linear estimators of the vector of unknown parameters in the deficient_rank linear model based on the spectral decomposition expression of the best linear minimun bias es... In this paper, we define a new class of biased linear estimators of the vector of unknown parameters in the deficient_rank linear model based on the spectral decomposition expression of the best linear minimun bias estimator. Some important properties are discussed. By appropriate choices of bias parameters, we construct many interested and useful biased linear estimators, which are the extension of ordinary biased linear estimators in the full_rank linear model to the deficient_rank linear model. At last, we give a numerical example in geodetic adjustment. 展开更多
关键词 deficient_rank model best linear minimum bias estimator generalized principal components estimator mean squared error condition number
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