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101.
徐红梅 《四川职业技术学院学报》2006,16(2):117-118
数据库存取技术在计算机应用系统中涉及很广泛,本文主要阐述了在Java中用使用JDBC访问数据库的方法,连接数据及其主流存取技术。 相似文献
102.
103.
刘智斌 《宁夏师范学院学报》2003,24(6):1-6
用R(L)-值下半连续函数引入了R(L)型诱导空间的概念.讨论了它的一些基本性质.证明了R(L)型诱导空间保持笛卡尔积;(L^x,δ)是连通空间当且仅当其R(L)型诱导空间是连通空间,给出了LF拓扑空间集与R(L)型诱导空间集之间建立的映射和生成映射ω的可交换性. 相似文献
104.
INTRODUCTION When the flexural load-carrying capacities of existing R. C. or P. C. structures are not sufficient for the service loads, structural strengthening becomes necessary. Using steel plates to strengthen concrete members is a traditional method (Raithby, 1980) and is still an important and popular way at the present time. Fiber-reinforced polymer (FRP) sheets and plates have been used recently as an alternative to steel plates for strengthening concrete structures be-cause th… 相似文献
105.
The promise of time-series designs for educational research and evaluation is reviewed. Ten time-series designs are presented and discussed in the context of threats to internal and external validity. The advantages and disadvantages of various visual and statistical data-analysis techniques are presented. It is argued that time-series research paradigms are useful when researchers (a) wish to involve a single subject in experimental research (individuals as units of analysis) or conduct program-evaluation studies (aggregates as units of analysis), (b) are interested in nearly continuous measurement, (c) cannot meet conventional design and statistical assumptions, or (d) wish to specify individual differences through N = 1 research strategies. It is also suggested that more research endeavors be devoted to combining unique characteristics of time-series research with conventional multi-unit paradigms. 相似文献
106.
付仁栋 《雁北师范学院学报》2004,20(5):103-106
该文介绍了能量转化与守恒定律发现的背景,并以迈耳、亥姆霍兹、焦耳等重要人物为线索,论述了能 量转化与守恒定律的发现过程. 相似文献
107.
陈潮华 《闽西职业技术学院学报》2007,9(2):86-88
生产实践表明,通过优化原材料的配方,改进工艺过程,利用粉煤灰,替代部分粘土原料,稳定生产32.5R普通硅酸盐水泥是可能的。 相似文献
108.
以阮冈纳赞的分面分类理论为切入点,阐述分面组配式分类法的特性、主题法及整个情报检索语言的发展趋势等问题。 相似文献
109.
To study the function of transforming growth factor β1 (TGF-β1) and transforming growth factor-β type II receptor (TGF-βR II) in varying stages of colorectal adenoma during neoplastic
transformation, fiftyfive cases of resected colorectal adenomas were examined immunohistochemically. Our results showed that
the expression of TGF-β1 ranged from high to low, with the progression of low-grade to high-grade dysplasia of adenomas to carcinoma. And there was
significantly different expression of TGF-β1 between moderate and high dysplasia adenomas (P<0.05), but no significantly different expression of TGF-β R II was found among varying stages of adenomas. Our results suggested
that the quantities of TGF-β1 secreted by adenoma cells decrease dramatically in moderate to severe dysplasia colorectal adenomas. It is the decreased
secretion of TGF-β1, rather than the mutated TGF-βR II that may play an important role in transforming colorectal adenomas to adenocarcinomas. 相似文献
110.
Yujiao Mai 《Structural equation modeling》2018,25(4):650-658
Multilevel modeling is a statistical approach to analyze hierarchical data that consist of individual observations nested within clusters. Bayesian method is a well-known, sometimes better, alternative of Maximum likelihood method for fitting multilevel models. Lack of user friendly and computationally efficient software packages or programs was a main obstacle in applying Bayesian multilevel modeling. In recent years, the development of software packages for multilevel modeling with improved Bayesian algorithms and faster speed has been growing. This article aims to update the knowledge of software packages for Bayesian multilevel modeling and therefore to promote the use of these packages. Three categories of software packages capable of Bayesian multilevel modeling including brms, MCMCglmm, glmmBUGS, Bambi, R2BayesX, BayesReg, R2MLwiN and others are introduced and compared in terms of computational efficiency, modeling capability and flexibility, as well as user-friendliness. Recommendations to practical users and suggestions for future development are also discussed. 相似文献