用复多值函数计算实积分的几个公式

本文用残数理论和实多值函数的有关知识出计算实积分的五个公式。     

18M跨度冷拔低炭钢丝预应力V形折板试验报告

一、概述: 折叠式予应力V形折板是一种新型板架合一结构,它具有显著的施工方便,节约三材,整体刚度好,抗震性能强等优点。自一九六七年出现以来,己在廿多个省市自洽区推广采用.据不完全统计已建面积近百万M2。当折板用于援外工程上时,立即得到受援国的欢迎,说明这种结构具有极大的生命力。在唐山大地震中,它又经受了最严重的地震力考验,从6度区直至震中附近的10度区,无一倒塌,在10度区的二座折板建筑,在地基下沉50公分,高层建筑外墙倒塌压在其上的情况下,仍能处于“震而不塌”,这说明它确是一种抗震性能极好的结构形式,在我国目前重视建筑的…     

Graph rigidity and localization of multi-robot formations

This paper provides theoretical foundation tor the problem ot localization in multi-robot formations. Sufficient and necessary conditions for completely localizing a formation of mobile robots/vehicles in SE(2) based on distributed sensor networks and graph rigidity are proposed. A method for estimating the quality of localizations via a linearized weighted least-squares algorithm is presented, which considers incomplete and noisy sensory information. The approach in this paper had been implemented in a multi-robot system of five car-like robots equipped with omni-directional cameras and IEEE 802.11b wireless network.     

Interaction of catechins with aluminum in vitro

Tea is one of the most popular beverages, consumed by over two thirds of the world's population; but the aluminum accumulation property of tea plant is becoming the focus of many researches because of aluminum's known adverse effect on human health. Investigation of the interactions of catechins with Al(3+) showed that during the interaction of catechins with Al(3+), the UV-vis spectrum of catechins was changed. Absorption of EGCG at 274 nm decreased and increased at 322 nm; EC and C's at 278 nm changed little. The ratio of Al(3+) to EGCG was 1:1 in pH 5.0 buffer solution; in pH 6.2 buffer solution, the ratio in the Al-EGCG complex was 1:1. Interestingly, while the ratio reached to over 2, after the complex of Al-EGCG started polymerization, the ratio in the polymer was 2:1. In pH 6.2 buffer solution, the complex behavior of C with Al(3+) was the same as that of EGCG, with a little difference for EC. When the ratio of Al(3+) to EC was <1, the complex in ratio was 1:2, but, the complex polymerized when the ratio of Al(3+) to EC was >1. It was found that the ratio of Al(3+) to EC in the polymer was 1:1. Polymerization of Al-catechin complexes might reduce aluminum absorption in the intestine. Kow value was also employed to study the properties of aluminum species in tea infusion (at gastric and intestine pH condition) and the effect of catechins and tea polyphenols on Kow in buffer solution. Results showed that Kow value rose much higher at the intestine pH than at the gastric pH. Tea polyphenols and catechins could greatly reduce aluminum Kow value in acetic buffer, indicating that these compounds may reduce aluminum absorption during tea intake.     

基于对等网络的信任模型

在Client/Server网络架构得到普遍应用的格局中,对等网络却异军突起迅速发展。针对这种新兴架构提出了与传统架构不同的一种安全信任模型。它依据网络的推荐值建立节点间的信任关系,更好地保证网络的安全性和避免恶意攻击。给出了求解信任值的数学模型和具体算法,并对信任模型的安全性能进行了理论评测。     

非线性微分方程本征值部分和的近似解法

在多粒子运动电子结构与能带问题的计算中,相当一类问题归结为用"第一原理\\"计算该系统本征值的电荷密度及能量的部分和,传统的迭代算法因计算量大而使问题的求解规模受到一定限制.文中将一类非线性微分方程本征值部分和的问题转化为非线性泛函的约束极值问题,通过空间分解和摄动原理,在二级近似下给出该泛函极小解的近似求解公式.算例表明该公式计算精度高,同时计算量可由O(n3)降至O(n2logn).     

基于卫星云图的无眼台风中心定位算法

基于数学形态学理论,采用球形结构元素设计了一种滚球滤波器,以去除红外卫星云图的噪声。采用多值自适应分割算法,生成自适应的分割模板,分割出主体台风云系。通过分析不同类型无眼台风云系的眼区特点,提出了具有自适应特性的无眼台风云系中心自动定位算法。通过红外通道和水汽通道的多谱图像融合,校验无眼台风中心的定位。实验结果表明,这种方法可以初步解决大部分无眼台风的中心定位。     

用于周期复振荡研究的微分方程解的一个结果*

提出了“组合优势条件”,并用其发民服Ｓ．Ｂａｎｋ和Ｊ．Ｌａｎｇｌｅｙ于１９９２年证明了的用于周期复振荡研究的一个重要结果,大大扩充了其适用性。