加速广义Laguerre多项式级数的Laplace变换的数值反演方法

本文利用Levin t-变换迭代法，对加速广义Laguerre多项式级数，提出了一种新的Laplace变换的数值反演方法，这种方法在精度上和数值稳定性上的效果都较好。     

草莓果实成熟期花青苷、酚类物质和类黄酮含量的变化

以春星和全明星为试材,研究了不同成熟度草莓果实酚类物质、类黄酮及花青苷的动态变化。结果表明,随着果实的成熟,酚类物质和类黄酮在绿熟期有较高的含量,之后随着果实的成熟先下降,至紫红期又开始大量积累;花青苷含量随着果实的成熟逐渐增加,紫红期达最大值;低温贮藏的草莓果实酚类物质、类黄酮含量首先下降,之后随着贮藏天数的增加而不断上升;花青苷含量逐渐增加,但增加的趋势比较缓慢。     

如何提升基层图书馆发展加速度的分析思考

为了充分发挥基层公共图书馆的整体优势和使用效益,实现文献资源的有效利用,南岗区图书馆从自身的实际出发,于2010年6月对阅览部开展了为期一个月的调查,其目的是要充分了解本馆报刊资源的利用情况,及怎样才能合理使用有限的购书经费,达到最大化满足读者的信息需求,尽快提升基层图书馆的服务水平和馆藏资源的建设。     

AN ACCELERATION SEARCH METHOD FOR UNCONSTRAINED OPTIMIZATION AND ITS APPLICATION IN MODEL PARAMETER ESTIMATION

In order to improve the convergence rate of the algorithms, an acceleration search method along a straight or curve is proposed,and the specific calculation steps of the algorithms are presented. The numerical results in model parameter estimation show that the convergence rate is improved and the calculation accords with the practical demands.     

Gastrointestinal and body growth in colostrum-deprived piglets in response to whey, casein or soy protein diets

Cow's milk stimulates growth in neonates and supplementation with specific milk proteins may benefit immuno-compromized neonates exhibiting poor growth. We investigated the effects of specific milk proteins (casein and whey) and plant protein (hydrolysed soy) on body and organ growth and bone mineralization in colostrum-deprived newborn pigs. Six days after birth, both casein and whey increased body and small intestinal weight relative to soy protein. Villus morphology and epithelial permeability were similar among groups. Casein significantly increased bone mineralization, while whey stimulated soft tissue growth (internal organs, muscle and fat). The differential effects of casein and whey proteins in the early postnatal period show that specific milk proteins rapidly affect whole body and gut development, even in a state of impaired growth induced by artificial feeding of colostrum-deprived pigs.     

Accumulation of Zinc and Molar Ratio of Phytic Acid and Zinc during Maize Grain Maturation

Dynamics of the accumulation of total ash and zinc, and their relationships with total dry matter, crude proteins and phytic acid during maize grain maturation were investigated. The investigation was carried out on normal maize hybrids grown under the same topographical and agrotechnical conditions over two consecutive vegetation years.
The amount of total ash, expressed on fresh and dry matter bases, changed significantly (P = 0.05 and P = 0.01) during grain maturation depending on maturity stage and variety. The dynamics of the accumulation of ash in fresh grain matter during maturation as well as the ash amount in dry matter of mature grains were significantly affected by environmental conditions.
The accumulation of zinc in fresh matter of developing grain was significantly affected (P = 0.05 and P = 0.01) by the degree of grain maturity and by variety, and correlates significantly (P = 0.001) and positively with the deposition of total dry matter, crude proteins as well as with phytic acid in both vegetation years.
The molar ratio of phytic acid and zinc increased significantly during grain maturation indicating a possible decrease of zinc availability.     

Identification of Acceleration Pulses of Near-Fault Earthquake Ground Motion by Wavelet

Acceleration pulses have been found in near-fault earthquake ground motions long ago and attracted lots of researchers, since such pulses, especially low frequency pulses have great impact on engineering structures. Many people previously focused on velocity pulses which result from acceleration pulses, however, recently a few researchers began to directly study acceleration pulses, such as to get high frequency pulses and low frequency pulses with empirical mode decomposition. Wavelet transform was utilized to decompose acceleration records. Subsequently high frequency and low frequency components of the records were obtained and acceleration pulses were identified. By comparisons in response spectra and structural nonlinear responses, it is proved that the decomposition of acceleration records with wavelet is reliable and the identification of acceleration pulses is correct.     

双轮驱动电动汽车防滑控制系统的研究

建立了双轮驱动电动汽车加速过程的1/4动力学模型,以滑转率为调节对象,提出了一种基于模糊自整定PID控制算法的驱动防滑控制系统.设计了双轮驱动电动汽车驱动防滑系统的模糊PID控制器,在Matlab/Simulink仿真环境下进行了动态仿真,对比仿真结果表明,模糊自整定PID控制器的性能优于单一的PID控制.