超超临界汽轮发电机组N+1支撑轴系失衡振动特性分析

建立了1000MW超超临界汽轮发电机组N+1支撑轴系的有限元动力学模型，对该种轴系的动力学特性及不平衡振动故障进行了仿真分析，归纳了该轴系轴向不同位置不平衡激起的轴系振动响应特性及转子间的相互影响规律，为该类机组的故障诊断及现场动平衡提供参考和依据。     

基于供应链业务流程改造的模块化设计

首先通过对A公司供应链业务流程现状进行分析,发现存在的问题,然后从模块化的角度对业务流程进行改造,并进一步对改造后的业务流程所涉及的4个模块进行了设计.所提出的供应链模块化设计,可将复杂流程简单化,使供应链管理更加明确、清晰,对于提高供应链的运作效率,缩短对需求响应时间具有重要作用.     

Image separation using wavelet-complex shearlet dictionary

This paper presents a new method for image separation through employing a combined dictionary consisting of wavelets and complex shearlets. Because the combined dictionary sparsely represents points and curvilinear singularities respectively, the image can be decomposed into pointlike and curvelike parts as accurate as possible. The proposed method based on the geo- metric separation theory introduced by Donoho in 2005 shows that accurate geometric separation of the morphologically distinct fea- tures of points and curves can be achieved by l1 minimization. The experimental results show that the proposed method can not only be effective but also greatly reduce the computing time.     

An important functional group,benzo[1,3]dioxole,of alkaloids induces the formation of the human telomeric DNA G-quadruplex

Over the past few decades, numerous molecules have been discovered or designed to interact efficiently and selectively with a peculiar DNA structure named G-quadruplex. Some of these molecules have been developed as anticancer agents. To aid the design of anticancer agents, the ability of alkaloids possessing Protoberberine and Benzophenanthridine groups to induce the formation of G-quadruplexes were studied using CD spectroscopy. By careful examination of their structures, we found that a benzo[1,3]dioxole group plays an important role in influencing their inductive properties. The more functional groups the alkaloids have, the stronger their G-quadruplex inductive ability.     

Geometric error control in the parabola-blending linear interpolator

This paper considers geometric error control in the parabola-blending linear interpolation method （Zhang, et al., 2011）. Classical model of chord error by approximation with contact circle on the parabolas leads to incorrect result. By computing the geometric error directly without accumulating the approximation error and chord error, the authors realize correct geometric error control by establishing inequality constraints on the accelerations of the motion.     

离子液体[C2mim]NO3与[C2mim][MetSO4]的热力学性能研究

采用MDY-2型密度仪在常压、一定温度范围内对离子液体1-乙基-3-甲基咪唑硝酸盐(简写为[C2mim]NO3)和1-乙基-3-甲基咪唑硫酸甲酯盐(简写为[C2mim][MetSO4])的密度进行了测定.结果表明,离子液体的密度随温度升高呈线性下降的趋势.由离子液体的密度值计算得到离子液体[C2mim]NO3和[C2m...     

Microstructure and properties of in-situ synthesized Cu-1 wt%TiC alloy followed by ECAP and post-annealing

A dispersion-strengthened copper alloy with 1 wt% TiC for commercial electrical-contact wires was prepared by in-situ reaction casting, grain-ultrafining by equal-channel angular pressing (ECAP) and subsequent annealing with aim to obtain excellent comprehensive performance. The results showed that fine TiC particles were in-situ synthesized in the as-cast Cu matrix and aggregated in clusters, and thus mechanical properties of the as-cast alloy deemed insufficient. Continued ECAP at 473 K significantly refined the grains of the as-cast alloy and improved the distribution of TiC particles. Due to multiple strengthening mechanisms, the ECAP-processed alloys maintained good conductivity with obviously enhanced tensile strength and hardness values. After post-ECAP annealing, the elongation and conductivity of the fine-grained copper alloy increased with the adequate tensile strength. The novel combined process endows the alloy appropriate performance to serve current high-frequency electrification railway systems.     

灰色理论在股市预测中的应用

灰色理论是上世纪八十年代发展起来的一门新学科,已经被成功地应用到经济、控制、工程等领域中。本文将灰色GM(1,1)模型应用于对股市的预测,并将所得值与由RBF网络预测的值进行线性组合以提高预测的精度。     

前S1抗原的检测及其与HBV血清标志物之间关系的探讨

目的了解前S1抗原和乙型肝炎病毒(HBV)血清标志物常见模式之间的关系,探讨前S1抗原检测的临床意义.方法采用双抗体夹心ELISA法对269例HbsAg阳性血清进行前S1抗原检测,并与相应的HBV血清标志物模式进行比较分析.结果HbeAg阳性组的前S1抗原阳性率无显著差别(P>0.05),HbsAg阳性组的前S1抗原阳性率也无显著差别(P>0.05).而HbeAg阳性组和HbsAg阳性组之间前S1抗原阳性率则存在显著差别(P<0.01),后者阳性率较高.结论前S1抗原与HBV血清标志物之间有一定关系,临床上宜将两者结合起来检测,综合判断.     

北斗一号卫星信号高灵敏度捕获方法

研究在复杂环境下弱北斗一号卫星信号的捕获方法.利用北斗一号卫星在同一频率上发射两个波束和帧头与卷尾组成已知连续信息序列的特点,可以对两个波束做长时间相干联合捕获.从增加捕获信号功率和减小非相干累加损失两个方面提高捕获灵敏度.仿真和实测结果表明,联合捕获方法可以捕获低于—133 dBm的信号,性能优于单波束串行搜索捕获方法.