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大豆配方施肥效果研究 被引量:4
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作者 金泽清 王鹏程 +1 位作者 邓可红 宋晓东 《湖北农业科学》 北大核心 2002年第5期73-74,共2页
在宜昌低山、丘陵区进行了大豆配方施肥试验,系统分析了9种不同施肥配方对大豆生长发育、产量性状、子粒外观品质等方面的影响。结果表明:大豆施用N、P、K复合肥+硼肥+钼肥的配方无论是播前施,还是叶面喷洒均有明显改善大豆生长发育状... 在宜昌低山、丘陵区进行了大豆配方施肥试验,系统分析了9种不同施肥配方对大豆生长发育、产量性状、子粒外观品质等方面的影响。结果表明:大豆施用N、P、K复合肥+硼肥+钼肥的配方无论是播前施,还是叶面喷洒均有明显改善大豆生长发育状况、提高产量的效果。其次是施用油菜子饼肥也能明显提高大豆产量。 展开更多
关键词 大豆 配方 施肥效果 生长发育 方差分差
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Phase aberration correction in ultrasonic phased array non-destructive testing systems
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作者 赵霞 王召巴 刘宾 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期47-52,共6页
Phase aberration correction for medical ultrasound systems has attracted a great deal of attention. Since phased array techniques are now widely employed for industrial non-destructive testing (NDT) applications in ... Phase aberration correction for medical ultrasound systems has attracted a great deal of attention. Since phased array techniques are now widely employed for industrial non-destructive testing (NDT) applications in various fields, the problem of phase aberrations in the process of NDT testing is considered. The technique of cross-covariance for phase aberration correction is presented. The performance of the technique for phase aberration correction is tested by means of echo signals obtained in practical non-destructive testing experiment. The results show that the technique has the better accuracy of phase correction. 展开更多
关键词 ultrasonic phased array non-destructive testing phase aberration CORRECTION cross-covariance method
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Effect of Varieties on Tea Pigment and Chromatic Aberration of Black Tea Infusion 被引量:5
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作者 刘千录 江用文 +4 位作者 江和源 张建勇 滑金杰 徐斌 薛金金 《Agricultural Science & Technology》 CAS 2014年第10期1654-1659,共6页
Effects of varieties on the content of tea pigment, L*, a* and b* value of chromatic aberration of black tea infusion was studied. The correlation relationship between content of TF, TR, TB and L*, a*, b* value ... Effects of varieties on the content of tea pigment, L*, a* and b* value of chromatic aberration of black tea infusion was studied. The correlation relationship between content of TF, TR, TB and L*, a*, b* value was extremely significant at P&lt;0.05. Fresh tea leaves with plucking standard of 1 bud and 2 leaves could man-ufacture black tea with higher content of tea pigment, higher a* and b* value but lower L* value, than those of plucking standard of 1 bud and 3 leaves. But the discrepancy of certain parameter of the two plucking standards changed with vari-eties. Varieties’ quality potential could be concealed by improper plucking standards. Six varieties were divided into four groups on the basis of gross tea polyphenols in fresh tea leaves (GTP), consumption of tea polyphenols to gross tea polyphenols ratio (CTP/GTP) and gross tea pigment to consumption of tea polyphenols ratio (GP/CTP). Hybrid performed the very suitability of black tea manufacturing. To en-sure high quality of made black tea, suitable variety should be chosen and reason-able plucking standard also should be taken into consideration. 展开更多
关键词 VARIETIES Plucking Standard Tea Pigment Chromatic Aberration Correlation Analysis ANOVA Analysis
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Clarkson-Kruskal Direct Similarity Approach for Differential-Difference Equations 被引量:2
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作者 SHEN Shou-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期964-966,共3页
In this letter, the Clarkson-Kruskal direct method is extended to similarity reduce some differentialdifference equations. As examples, the differential-difference KZ equation and KP equation are considered.
关键词 differential-difference KZ equation differential-difference KP equation direct method similarity reduction
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Finite difference method for dynamic response analysis of anchorage system 被引量:5
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作者 言志信 段建 +3 位作者 江平 刘子振 赵红亮 黄文贵 《Journal of Central South University》 SCIE EI CAS 2014年第3期1098-1106,共9页
Based on some assumptions, the dynamic analysis model of anchorage system is established. The dynamic governing equation is expressed as finite difference format and programmed by using MATLAB language. Compared with ... Based on some assumptions, the dynamic analysis model of anchorage system is established. The dynamic governing equation is expressed as finite difference format and programmed by using MATLAB language. Compared with theoretical method, the finite difference method has been verified to be feasible by a case study. It is found that under seismic loading, the dynamic response of anchorage system is synchronously fluctuated with the seismic vibration. The change of displacement amplitude of material points is slight, and comparatively speaking, the displacement amplitude of the outside point is a little larger than that of the inside point, which shows amplification effect of surface. While the axial force amplitude transforms considerably from the inside to the outside. It increases first and reaches the peak value in the intersection between the anchoring section and free section, then decreases slowly in the free section. When considering damping effect of anchorage system, the finite difference method can reflect the time attenuation characteristic better, and the calculating result would be safer and more reasonable than the dynamic steady-state theoretical method. What is more, the finite difference method can be applied to the dynamic response analysis of harmonic and seismic random vibration for all kinds of anchor, and hence has a broad application prospect. 展开更多
关键词 anchorage system dynamic response finite difference method attenuation characteristic
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Quantifying the attribution of model bias in simulating summer hot days in China with IAP AGCM 4.1 被引量:4
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作者 LIN Zhao-Hui YU Zheng +1 位作者 ZHANG He WU Cheng-Lai 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第6期436-442,共7页
Using lAP AGCM simulation results for the period 1961-2005, summer hot days in China were calculated and then compared with observations. Generally, the spatial pattern of hot days is reasonably reproduced, with more ... Using lAP AGCM simulation results for the period 1961-2005, summer hot days in China were calculated and then compared with observations. Generally, the spatial pattern of hot days is reasonably reproduced, with more hot days found in northern China, the Yangtze and Huaihe River basin, the Chuan-Yu region, and southern Xinjiang. However, the model tends to overestimate the number of hot days in the above-mentioned regions, particularly in the Yangtze and Huaihe River basin where the simulated summer-mean hot days is 13 days more than observed when averaged over the whole region, and the maximum overestimation of hot days can reach 23 days in the region. Analysis of the probability distribution of daily maximum temperature (Trnax) suggests that the warm bias in the model-simulated Tmax contributes largely to the overestimation of hot days in the model. Furthermore, the discrepancy in the simulated variance of the Tmax distribution also plays a non- negligible role in the overestimation of hot days. Indeed, the latter can even account for 22% of the total bias of simulated hot days in August in the Yangtze and Huaihe River basin. The quantification of model bias from the mean value and variability can provide more information for further model improvement. 展开更多
关键词 Hot days variance inprobability distribution bias attribution modelevaluation IAP AGCM
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The Two Patterns of High Exact Difference in Convection Equation 被引量:2
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作者 YANGHui PENGXing 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期328-330,共3页
This paper gives two patterns of high exact d ifference in solving convection equation. The error of cut section is to O(Δ t 2+Δx 4).
关键词 convection equation the pattern of difference the e rror of cut section
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Influence of process parameters on deep drawing of AA6111 aluminum alloy at elevated temperatures 被引量:8
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作者 马闻宇 王宝雨 +2 位作者 傅垒 周靖 黄鸣东 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1167-1174,共8页
To gain a deep insight into the hot drawing process of aluminum alloy sheet, simulations of cylindrical cup drawing at elevated temperatures were carried out with experimental validation. The influence of four importa... To gain a deep insight into the hot drawing process of aluminum alloy sheet, simulations of cylindrical cup drawing at elevated temperatures were carried out with experimental validation. The influence of four important process parameters, namely,punch velocity, blank holder force(BHF), friction coefficient and initial forming temperature of blank on drawing characteristics(i.e.minimum thickness and thickness deviation) was investigated with the help of design of experiments(DOE), analysis of variance(ANOVA) and analysis of mean(ANOM). Based on the results of ANOVA, it is shown that the blank holder force has the greatest influence on minimum thickness. The importance of punch velocity for thickness deviation is 44.35% followed by BHF of 24.88%,friction coefficient of 15.77% and initial forming temperature of blank of 14.995%. After determining the significance of each factor on forming characteristics, how the individual parameter affects characteristics was further analyzed by ANOM. 展开更多
关键词 aluminum process parameters finite element method hot drawing analysis of variance analysis of mean
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Analysis of passenger boarding time difference between adults and seniors based on smart card data
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作者 Lei Da Chen Xuewu +1 位作者 Cheng Long Luo Ronggen 《Journal of Southeast University(English Edition)》 EI CAS 2019年第1期97-102,共6页
As an essential component of bus dwelling time, passenger boarding time has a significant impact on bus running reliability and service quality. In order to understand the passengers’ boarding process and mitigate pa... As an essential component of bus dwelling time, passenger boarding time has a significant impact on bus running reliability and service quality. In order to understand the passengers’ boarding process and mitigate passenger boarding time, a regression analysis framework is proposed to capture the difference and influential factors of boarding time for adult and elderly passengers based on smart card data from Changzhou. Boarding gap, the time difference between two consecutive smart card tapping records, is calculated to approximate passenger boarding time. Analysis of variance is applied to identify whether the difference in boarding time between adults and seniors is statistically significant. The multivariate regression modeling approach is implemented to analyze the influences of passenger types, marginal effects of each additional boarding passenger and bus floor types on the total boarding time at each stop. Results show that a constant difference exists in boarding time between adults and seniors even without considering the specific bus characteristics. The average passenger boarding time decreases when the number of passenger increases. The existence of two entrance steps delays the boarding process, especially for elderly passengers. 展开更多
关键词 elderly passengers smart card data boarding time differences analysis of variance regression analysis marginal effect
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Affective Meaning of Pronouns in a Russian Sample
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作者 Leonid Dorfman 《Journal of Literature and Art Studies》 2016年第9期1042-1055,共14页
The present study examines affective meaning of pronouns (in Russian) represented by the semantic differential. Of direct relevance to the present study is the theory of affective meaning propounded by Osgood. Two h... The present study examines affective meaning of pronouns (in Russian) represented by the semantic differential. Of direct relevance to the present study is the theory of affective meaning propounded by Osgood. Two hypotheses were tested. According to a "magnitude" hypothesis, affective dimensions (each of evaluation, potency, and activity taken separately) differ in their magnitude across pronouns I, My, Me, and They. A "structural" hypothesis stated that the affective dimensions yield latent factors across (the generality) and within (the concept-scale interaction) the pronoun concepts. Repeated-measures analysis of variance (1-way ANOVA) and confirmatory factor analysis were employed to process data. It was found that each of the evaluation and potency measures yield a significant magnitude change across the pronouns, but there was indicated no significant change across the pronouns with respect to the activity dimension. Therewith, the pronoun My gained a salient value and the pronoun They the smallest value. Using confirmatory factor analysis five models were tested. Among them one model was good fit to the data. It engaged a four-factor solution resulted in that four pronouns are latent affective distinct but related factors and the evaluation, potency, and activity are their indicators. 展开更多
关键词 personal pronouns affective meaning semantic differential GENERALITY concept-scale interaction
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An Investigation of Buckled of Column on Liner Elastic foundation by Using Finite-Difference Mode
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作者 Huan Luo QinghuaYang 《International Journal of Technology Management》 2014年第8期162-163,共2页
The use of columns on elastic foundation is very common in Civil Engineering, like bridge pier, the foundation of the buildings etc. So, it will be useful to find the critical load for the structure, the problem in th... The use of columns on elastic foundation is very common in Civil Engineering, like bridge pier, the foundation of the buildings etc. So, it will be useful to find the critical load for the structure, the problem in this paper will be solved by Finite-Difference Mode, that' s simple and has an extensive use. The way it works is that by dividing the component into many units. Finite-difference methods (FDM) are numerical methods for anoroximating, the solutions to differential eauations usine finite difference equations to approximate derivatives. 展开更多
关键词 Finite-difference methods (FDM) BUCKLING liner function buckling load
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Maximum Posterior Adjustment of Extended Network and Estimation Formulae of Its Variance Components
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作者 汪善根 《Journal of China University of Mining and Technology》 2001年第2期108-112,共5页
This paper derives the maximum posterior adjustment formulae of the extended network and the estimation formulaes of variance components of Helmert, Welsch and Frstner types when there are two types of uncorrelated ob... This paper derives the maximum posterior adjustment formulae of the extended network and the estimation formulaes of variance components of Helmert, Welsch and Frstner types when there are two types of uncorrelated observations in it, and perfects the theory of the maximum posterior adjustment. 展开更多
关键词 common parameter priori weight extended network variance components
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A Finite Volume Backward Euler Difference Method for Nonlinear Parabolic Integral-differential Equation
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作者 王波 王强 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第3期370-377,共8页
The Finite volume backward Euler difference method is established to discuss two-dimensional parabolic integro-differential equations.These results are new for finite volume element methods for parabolic integro-diffe... The Finite volume backward Euler difference method is established to discuss two-dimensional parabolic integro-differential equations.These results are new for finite volume element methods for parabolic integro-differential equations. 展开更多
关键词 finite volume element integro-differential equations initial boundary problem optimal error estimates
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Analysis and Translation Strategies on Cultural Differences Between Chinese and Western
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作者 GAO Bei ZHOU Wei 《Sino-US English Teaching》 2014年第12期952-961,共10页
Language and culture are interactive and interdependent. Translation is not only the transfer between two languages, but also between two cultures. Therefore, cultural difference plays a significant role in translatio... Language and culture are interactive and interdependent. Translation is not only the transfer between two languages, but also between two cultures. Therefore, cultural difference plays a significant role in translation. In the past decades, translation study has shifted from the purely linguistic level to cultural perspective, and study on cultural differences has brought a new world for the sake of translation studies. This paper tries to illustrate the connection between language and culture, the correlation between culture and translation, analyze the main aspects of cultural differences between Chinese and Western, and sum up translation strategies of domestication and foreignization as well as specific translation methods on the consideration of cultural differences. Finally, the paper proposes that translators should pay attention to cultural differences and adjust target text in accordance with cultural differences 展开更多
关键词 cultural differences translation strategies DOMESTICATION FOREIGNIZATION
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Correction of Dynamic Error Result from Measurement System Limitations 被引量:1
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作者 张志杰 王代华 +1 位作者 王文廉 王巍 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期307-311,共5页
The main cause of dynamic errors is due to frequency response limitation of measurement system. One way of solving this problem is designing an effective inverse filter. Since the problem is ill-conditioned, a small u... The main cause of dynamic errors is due to frequency response limitation of measurement system. One way of solving this problem is designing an effective inverse filter. Since the problem is ill-conditioned, a small uncertainty in the measurement will came large deviation in reconstncted signals. The amplified noise has to be suppressed at the sacrifice of biasing in estimation. The paper presents a kind of designing method of inverse filter in frequency domain based on stabilized solutions of Fredholm integral equations of the fast kind in order to reduce dynamic errors. Compared with previous several work, the method has advantage of generalization. Simulations with different Signal-to-Noise ratio (SNR) are investigated. Flexibility of the method is verified. Application of correcting dynamic error is given. 展开更多
关键词 dynamic error inverse filters oorrection of dynamic dlaracteristic measurement system
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Risk in the Prices of Fossil Fuels for Japanese Electric Utility Sector
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作者 K. Suzuki D. Masukawa Y. Uchiyama 《Journal of Energy and Power Engineering》 2010年第10期9-16,共8页
A risk in the prices of fossil fuels is a major concern to importing countries of them. This study analyzes the risk of an increase in the cost for Japanese electric utility sector during the period 1978-2007 consider... A risk in the prices of fossil fuels is a major concern to importing countries of them. This study analyzes the risk of an increase in the cost for Japanese electric utility sector during the period 1978-2007 considering the uncertainty in the prices of fossil fuels. The mean-semivariance model, which uses an upper semivariance as an index of the risk, is adopted for the purpose. The result confirms that the semivariance is the better index of the risk than the variance. Furether, the semivariance is decomposed into two factors; the risk caused by price changes in an individual fossil fuel source and the risk caused by correlations among the changes in the prices of fossil fuel sources. The former has been kept at a low level as it appears to be easy to estimate, while the latter has not been maintained at the lowest level as it appears to be difficult to estimate. The Japanese electric utility sector followed the minimum-risk fossil fuel mix up until 2001, but discontinued the same post 2001. 展开更多
关键词 Mean-semivariance model energy security fossil fuel mix Japan.
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Gender Differences in Auditory Perception and Computational Divided Attention Tasks
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作者 Bankole K. Fasanya Maranda E. McBride: +1 位作者 Regina Pope-Ford Celestine Ntuen 《Computer Technology and Application》 2012年第9期636-641,共6页
Women have been stereotyped as better multitaskers when compared to their male counterparts. The purpose of this study is to investigate whether there are differences in gender performance when performing cognitive co... Women have been stereotyped as better multitaskers when compared to their male counterparts. The purpose of this study is to investigate whether there are differences in gender performance when performing cognitive combined tasks. Twenty-four graduate students (twelve females and twelve males) volunteered to participate in the study. The task requires participants to indicate when they perceive a change in the intensity of an auditory signal while simultaneously solving algebraic problems. Multivariate Analysis of Variance (MANOVA) results reveal no significant differences between genders when performing the combined tasks (p = 0.1831 and 2 = 0.7891) although the average number of false alarms made during the combined tasks by males is nearly 11% higher than the average number of false alarms made by females. However, (Multivariate Analysis of Variance) ANOVA results for the combined tasks show that males outperform females on the computational task while listening for changes in the auditory signal F(1, 22) - 5.09, p 〈 0.03, but there are no significant differences in their ability to detect noise intensity variation or in the number of false alarms made while multitasking. For the single task analysis the ANOVAs indicate no significant differences in signal detection task performance, computational task performance, or the number of false alarms made by males and females. 展开更多
关键词 Pink noise background noise tolerance level (BNTL) multitasking acoustic chamber azimuths.
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Mathematical Model for Takeoff Simulation of a Wing in Proximity to the Ground
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作者 Omer Kemal Kinaci 《Journal of Marine Science and Application》 CSCD 2016年第2期136-143,共8页
Aircraft flying close to the ground benefit from enhanced efficiency owing to decreased induced drag and increased lift. In this study, a mathematical model is developed to simulate the takeoff of a wing near the grou... Aircraft flying close to the ground benefit from enhanced efficiency owing to decreased induced drag and increased lift. In this study, a mathematical model is developed to simulate the takeoff of a wing near the ground using an Iterative Boundary Element Method (IBEM) and the finite difference scheme. Two stand-alone sub-codes and a mother code, which enables communication between the sub-codes, are developed to solve for the self-excitation of the Wing-In-Ground (WIG) effect. The aerodynamic force exerted on the wing is calculated by the first sub-code using the IBEM, and the vertical displacement of the wing is calculated by the second sub-code using the finite difference scheme. The mother code commands the two sub-codes and can solve for the aerodynamics of the wing and operating height within seconds. The developed code system is used to solve for the force, velocity, and displacement of an NACA6409 wing at a 4° Angle of Attack (AoA) which has various numerical and experimental studies in the literature. The effects of thickness and AoA are then investigated and conclusions were drawn with respect to generated results. The proposed model provides a practical method for understanding the flight dynamics and it is specifically beneficial at the pre-design stages of a WIG effect craft. 展开更多
关键词 wing-in-ground effect ground proximity flightdynamics iterative boundary element method mathematical model takeoff simulation
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Regression Model to Analyze Differential Response to Treatment in Randomized Controlled Clinical Trial
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作者 A.K. Mathai B.N. Murthy 《Journal of Mathematics and System Science》 2013年第9期419-425,共7页
The primary aim of clinical trials is to investigate whether a treatment is effective for a particular disease or condition. Randomized controlled clinical trials are considered to be the gold standard for evaluating ... The primary aim of clinical trials is to investigate whether a treatment is effective for a particular disease or condition. Randomized controlled clinical trials are considered to be the gold standard for evaluating the effect of a certain intervention. However, in clinical trials, even after randomization, there are situations where the patients differ substantially with respect to the baseline value of the outcome variable. Many a times the response to interventions depends on the baseline values of the outcome variable. When there are baseline-dependent treatment effects, differences among treatments vary as a function of baseline level. Although variation in outcome associated with baseline value is accounted for in ANCOVA, analysis of individual differences in treatment effect is precluded by the homogeneity of regression assumption. This assumption requires that expected differences in outcome among treatments be constant across all baseline levels. To overcome this difficulty, Weigel and Narvaez [7] proposed a regression model for two treatment groups to analyze individual response to treatments in randomized controlled clinical trials. The authors reviewed the model suggested by Weigel and Narvaez and extended further for three or more treatment groups. The utility of the model was demonstrated with real life data from a randomized controlled clinical trial of bronchial asthma. 展开更多
关键词 Regression model differential response placebo effect clinical trial.
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Optimal l~∞ error estimates of finite difference methods for the coupled Gross-Pitaevskii equations in high dimensions 被引量:11
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作者 WANG TingChun ZHAO XiaoFei 《Science China Mathematics》 SCIE 2014年第10期2189-2214,共26页
Due to the difficulty in obtaining the a priori estimate,it is very hard to establish the optimal point-wise error bound of a finite difference scheme for solving a nonlinear partial differential equation in high dime... Due to the difficulty in obtaining the a priori estimate,it is very hard to establish the optimal point-wise error bound of a finite difference scheme for solving a nonlinear partial differential equation in high dimensions(2D or 3D).We here propose and analyze finite difference methods for solving the coupled GrossPitaevskii equations in two dimensions,which models the two-component Bose-Einstein condensates with an internal atomic Josephson junction.The methods which we considered include two conservative type schemes and two non-conservative type schemes.Discrete conservation laws and solvability of the schemes are analyzed.For the four proposed finite difference methods,we establish the optimal convergence rates for the error at the order of O(h^2+τ~2)in the l~∞-norm(i.e.,the point-wise error estimates)with the time stepτand the mesh size h.Besides the standard techniques of the energy method,the key techniques in the analysis is to use the cut-off function technique,transformation between the time and space direction and the method of order reduction.All the methods and results here are also valid and can be easily extended to the three-dimensional case.Finally,numerical results are reported to confirm our theoretical error estimates for the numerical methods. 展开更多
关键词 coupled Gross-Pitaevskii equations finite difference method SOLVABILITY conservation laws pointwise convergence optimal error estimates
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