单位宽度轧制力对热轧带钢凸度的影响规律

为了建立高精度的热轧带钢凸度计算数学模型 ,根据带钢凸度计算理论 ,采用影响函数法开发了四辊轧机带钢凸度影响率计算软件 ,系统地分析了单位宽度轧制力、轧辊直径和压下量对单位宽度轧制力影响率的影响规律·结果表明单位宽度轧制力影响率随带钢宽度的增加呈抛物线变化 ;轧辊直径和压下量对单位宽度轧制力影响率有一定的影响 ;建立了高精度单位宽度轧制力影响率的数学模型 ,确定了单位宽度轧制力影响率基本值及工作辊直径、支撑辊直径、压下量对单位宽度轧制力影响率修正系数的 6次拟合系数 ,为板形控制系统模型的建立及参数优化提供了理论依据     

非正交码移键控和码索引调制算法

针对正交码移键控(code shift keying, CSK)误比特率(bit error rate, BER)性能下降和非正交码索引调制(non-orthogonal-code index modulation, N-CIM)未能充分利用扩频码自相关性的不足,提出一种非正交CSK和码索引调制(non-orthogonal-CSK-code index modulation, N-CSK-CIM)算法。发送端信息比特分为调制比特和扩频码映射比特;调制比特用来进行符号调制,映射比特映射为扩频码的索引和码相位索引。首先根据调制比特进行符号调制,然后利用映射比特映射的扩频码索引选择同一原始扩频码,并根据码相位索引进行码移键控产生新的扩频码,调制后的符号实部与虚部分别用这一新的扩频码进行扩频。仿真结果表明,在加性高斯白噪声(additive white Gaussian noise, AWGN)信道和瑞利衰落信道中,相同信噪比时, N-CSK-CIM算法的BER性能优于N-CIM算法和正交CSK算法。     

高性能混凝干早期抗裂研究

为减小高性能混凝土早期开裂,利用非接触测量技术,测量了高性能混凝土早期自生及单面干燥条件下的收缩,研究了减缩剂、聚丙烯纤维等几种作用机理不同的物质对高性能混凝土早期自生及干燥收缩的影响.在此基础上,利用板式混凝土早期收缩开裂试验架,对高性能混凝土进行了约束试验,研究了减缩剂、减缩剂+聚丙烯纤维等对高性能混凝土早期抗裂的作用.结果表明:减缩剂、聚丙烯纤维、减缩剂+聚丙烯纤维及渗透结晶防水涂料均有减缩抗裂效果,其作用大小为渗透结晶防水涂料＞减缩剂＞减缩剂+聚丙烯纤维＞聚丙烯纤维.     

ABg型树枝状高分子生长物理缺陷的理论研究

根据超支化高分子生长的空间位阻效应,通过利用简单的统计模型分析了ABg型反应体系在临界生长代数时形成缺陷结构的物理过程,进一步给出了临界反应代数与官能团之间的关系,扼要地讨论了超支化高分子的折光指数随生长代数的变化情况.     

Identification of two related pentapeptides from the brain with potent opiate agonist activity.

Enkephalin, a natural ligand for opiate receptors is composed of the pentapepides H-Tyr-Gly-Gly-Phe-Met-OH and H-Tyr-Gly-Gly-Phe-Leu-OH. The evidence is based on the determination of the amino acid sequence of natural enkephalin by the dansyl-Edman procedure and by mass spectrometry followed by synthesis and comparison of the natural and synthetic peptides.     

Pleiotropic fitness effects of the Tre1-Gr5a region in Drosophila melanogaster

The abundance of transposable elements and DNA repeat sequences in mammalian genomes raises the question of whether such insertions represent passive evolutionary baggage or may influence the expression of complex traits. We addressed this question in Drosophila melanogaster, in which the effects of single transposable elements on complex traits can be assessed in genetically identical individuals reared in controlled environments. Here we demonstrate that single P-element insertions in the intergenic region between the gustatory receptor 5a (Gr5a, also known as Tre) and trapped in endoderm 1 (Tre1), which encodes an orphan receptor, exert complex pleiotropic effects on fitness traits, including selective nutrient intake, life span, and resistance to starvation and heat stress. Mutations in this region interact epistatically with downstream components of the insulin signaling pathway. Transposon-induced sex-specific and sex-antagonistic effects further accentuate the complex influences that intergenic transposable elements can contribute to quantitative trait phenotypes.     

Identification of the gene responsible for methylmalonic aciduria and homocystinuria, cblC type

Methylmalonic aciduria and homocystinuria, cblC type (OMIM 277400), is the most common inborn error of vitamin B(12) (cobalamin) metabolism, with about 250 known cases. Affected individuals have developmental, hematological, neurological, metabolic, ophthalmologic and dermatologic clinical findings. Although considered a disease of infancy or childhood, some individuals develop symptoms in adulthood. The cblC locus was mapped to chromosome region 1p by linkage analysis. We refined the chromosomal interval using homozygosity mapping and haplotype analyses and identified the MMACHC gene. In 204 individuals, 42 different mutations were identified, many consistent with a loss of function of the protein product. One mutation, 271dupA, accounted for 40% of all disease alleles. Transduction of wild-type MMACHC into immortalized cblC fibroblast cell lines corrected the cellular phenotype. Molecular modeling predicts that the C-terminal region of the gene product folds similarly to TonB, a bacterial protein involved in energy transduction for cobalamin uptake.     

基于IMM的高动态GPS接收机载波跟踪算法

利用交互式多模型的带宽自适应调整特性实现了高动态与静态环境下通用的GPS信号载波跟踪算法。仿真结果表明,该算法在保证满足高动态GPS信号载波跟踪要求的前提下,降低了静态时的频率跟踪误差,避免了不同动态环境下多个载波跟踪算法及切换方案的设计。     

光学纤维面板熔压设备的研究与开发

为解决生产光学纤维面板的传统熔压设备存在的控制精度低和重复精度低的问题,基于液压比例反馈技术和传感器检测技术,开发了一种光学纤维面板自动熔压设备.介绍了其熔压原理、工艺流程及结构特点,并对设备改造的核心部分液压控制系统的原理进行了详细的说明.实验测试结果表明:该设备自动化程度高,工艺参数控制精度不低于国内外同类先进设备,温度控制精度达±0.1℃,真空度控制精度为±2 Pa,压力控制精度达±1%,为光纤面板加工和工艺研发提供了一种新的手段.     

基于Rough Sets-C4.5的故障征兆提取与判别

针对原始信息系统往往存在大量重复样本和冗余属性,从而影响实际故障诊断的精度和速度这一问题,介绍了一种基于粗糙集和决策树C4.5算法相融合的故障诊断模型,用于设备的精确和快速故障诊断.利用粗糙集具有较强的处理不确定和不完备信息的能力,对原始样本集进行离散化及约简处理;同时,利用决策树C4.5算法对约简后的决策表进行快速学习并形成树状故障分类器.以实例介绍了利用该模型进行故障诊断的完整过程.