建筑墙体表面传热系数辨识研究

对实验房间南向墙体内表面中心区域的换热过程进行实验，发现当风速在0－5．5m/s之间时，表面传热系数在8－18W（m^2.K）之间波动，而风向对墙体表面传热系数影响不大；用辅助变量法分析墙体表面传热过程，并结合实验推导出墙体表面传热系数。模型的预测结果与实测结果吻合良好。     

三峡地下电站变顶高尾水洞水动力特性

在国内首次应用模型水轮发电机组对三峡地下电站变顶高尾水洞方案进行水力过渡过程试验研究。对水轮机导叶实行分段关闭 ,并求出了二段关闭的最佳拐点 ,试验证实了二段关闭对减小尾水管进口的负压和机组转速上升有明显的作用。通过有关水力参数的测试 ,认为变顶高尾水洞可以满足各项技术要求 ,是一个减少山体开挖、节省投资的新型设计方案。在地下电站中具有广泛的应用前景     

A Bayesian propensity score adjustment for latent variable modeling and MCMC algorithm

The estimation of the differences among groups in observational studies is frequently inaccurate owing to a bias caused by differences in the distributions of covariates. In order to estimate the average treatment effects when the treatment variable is binary, Rosenbaum and Rubin [1983. The central role of the propensity score in observational studies for causal effects. Biometrika 70, 41-55] proposed an adjustment method for pre-treatment variables using propensity scores. Imbens [2000. The role of the propensity score in estimating dose-response functions. Biometrika 87, 706-710] extended the propensity score methodology for estimation of average treatment effects with multivalued treatments.However, these studies focused only on estimating the marginal mean structure. In many substantive sciences such as the biological and social sciences, a general estimation method is required to deal with more complex analyses other than regression, such as testing group differences on latent variables. For latent variable models, the EM algorithm or the traditional Monte Carlo methods are necessary. However, in propensity score adjustment, these methods cannot be used because the full distribution is not specified.In this paper, we propose a quasi-Bayesian estimation method for general parametric models that integrate out the distributions of covariates using propensity scores. Although the proposed Bayes estimates are shown to be consistent, they can be calculated by existing Markov chain Monte Carlo methods such as Gibbs sampler. The proposed method is useful to estimate parameters in latent variable models, while the previous methods were unable to provide valid estimates for complex models such as latent variable models.We also illustrated the procedure using the data obtained from the US National Longitudinal Survey of Children and Youth (NLSY1979-2002) for estimating the effect of maternal smoking during pregnancy on the development of the child's cognitive functioning.     

未结盟大学的联盟

通过梳理管理学界对战略联盟的定义，发现价值链的鸸释同样适用于大学问的战略联盟。通过对已有的大学战略联盟的分析，提出了名校联盟与非名校联盟间的若干差异，最后提出了我国大学联盟战略的若干建议。     

变频器在暖通空调行业中的应用

本文提出中央空调系统的一种变频调速改造方案，介绍了该系统的结构组成及运行原理，对系统各部分的作用进行了讨论。     

高速逆流色谱(HSCCC)在食品色素制备中的应用

综述了高速逆流色谱在食品色素制备中的应用情况，包括溶剂选择、色素种类等。     

Heterogeneous chain propagation in low-pressure flames

An analysis of papers on hydrogen combustion at low pressures is performed, which refines the contribution of the catalytic reactions on the reactor wall to the gas-phase part of the process. A new model for the heterogeneous loss of active reaction centers was proposed and tested experimentally to explain inconsistencies that occur in some papers. In this model, the diffusion region of chain termination is formed under standard experimental conditions in vacuum oxyhydrogen flames at a reactor gas pressure a thousand times lower than the boundary pressure postulated by the previous models as the pressure below which the diffusion region of chain termination cannot be formed. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 2, pp. 10–18, March–April, 2006.     

靶向抗癌药格列卫与其治疗白血病疗效监测

Gleevec是抑制致癌的融合蛋白BCR-ABL的一种分子靶向治疗药物,BCR-ABL是一种与慢性髓细胞性白血病(CML)有关的酪氨酸激酶抑制剂。用Gleevec选择性地抑制BCR-ABL活性在治疗CML中显示出很好的效果,特别是在CML慢性期,因此,监测疗效非常重要。现就Gleevec的研究进展及如何监测其在CML中的疗效作一简单综述。     

马尔可夫链在企业经济预测上的应用

为了科学的预测企业所关心的各项经济指标 ,以便为企业的未来做出正确的决策方案 ,需用适当的数学模型和方法对企业的经济活动进行定量的研究 .基于经济活动的复杂、多变性及带有许多随机性因素的特点 ,针对这两种常见的经济问题 ,分别建立了相应的马尔可夫链模型 .应用马尔可夫链的相关理论、巧妙的构造转移概率矩阵 ,只通过简单的矩阵运算 ,便迅速解决问题 .实例表明 ,马尔可夫链模型及方法在企业经济活动分析中是可行和适用的 ,可广泛用于解决企业中常见的预测及决策问题 .     

Extracellular polysaccharides production by Arthrobacter viscosus

In this study the production of extracellular polysaccharides by the non-pathogenic soil bacteria Arthrobacter viscosus has been investigated. Different variables affecting extracellular polysaccharide production such as the carbon source (glucose or xylose), the agitation speed and the pH have been analysed.

In a first stage, experiments in shaken conical flasks (250 ml), containing 50 ml of culture medium, were carried out. Using xylose (25 g/l) as the carbon source at an initial pH 8 improved the extracellular polysaccharides levels obtained.

In a second stage, the experiments were scaling in bioreactors. Cultivation was carried out in discontinuous mode and with/without pH control. Polysaccharide production reached a maximum of 10 g of crude product per litre of growth medium after 14 days and the relationship between product formation and cell growth of A. viscosus is 2.7 g polysaccharide per gram biomass. This production was obtained at the optimal conditions determined with pH control at pH 7, xylose as carbon source (25 g/l) and an agitation rate of 800 rpm.