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991.
随着业务的不断扩展和信息化的持续深入,银行信息系统越来越复杂,对信息系统的依赖程度也越来越高,信息系统运行的稳定与否直接关系到业务连续性。有关专家认为,如何合理地利用IT资源、有效地控制IT风险和提高IT服务质量已成为银行业高度关注的课题。ITIL(IT基础设施库)的引入和应用,可以解决企业IT系统的运维难题,提高企业IT运维效率和IT服务满意度。 相似文献
992.
A micro-envioment for nerve cells and tissue growth were designed and constructed via surface modification of poly(L-lactide-co-glycolide)(PLGA)
with chitosan and hydroxyapatite(HA). The poly(L-lactide-co-glycolide)/chitosan/hydroxyapatite (PLGA/chitosan/HA) conduits
were manufactured by a combined solvent casting and particulate leaching technique. The conduits were highly porous with an
interconnected pore structure and 76.5% porosity. Micropores with 50–100 micrometer diameter were formed in the conduits.
In vivo application of PLGA/chitosan/HA conduits for reconstruction of 10 mm sciatic nerve defect was assessed by the walking
track analysis, the quantifying of the wet weight of tibialis anterior muscle and the histological assessment. The conduits
in host rats in vivo can not only be an effective in promoting regenerating of nerves but can also lead to favorable nerve
functional recovery.
Funded by the National Natural Science Foundation of China(No.50774096) 相似文献
993.
周杰 《武汉理工大学学报(材料科学英文版)》2009,24(2):330-332
A new method was used to evaluate the fatigue properties of the bonding layer used in the bridge deck pavement. The shear
fatigue test of three bonding layers was conducted on a dynamic shear rheometer(DSR). The fatigue formulas were gained for
these layers. The experimental results indicate that, at the same torque level or at the same frequency, neoprene latex asphalt
bonding layer exhibits excellent fatigue performance when compared to other two bonding layers.
Funded by the National Natural Science Foundation of China (No. 50878171) 相似文献
994.
陈文怡 《武汉理工大学学报(材料科学英文版)》2009,24(1):38-41
A stainless steel/10wt%TiC nanocomposite particles were prepared by high-energy ball-milling method using stainless steel,
carbon and titanium as raw materials. The evolution of phase composition, microstructure and specific surface area of the
stainless steel/TiC nanocomposite particles with increasing ball-milling time in the range of 0–100 h were investigated by
XRD, SEM, TEM and BET techniques. The results showed that the stainless steel/TiC nanocomposite particles were fabricated
when the ball-milling time was longer than 20 h. However, the nanocomposite particles were soldered and agglomerated again
when the ball-milling time was longer than 60 h. The microstructure of the composite particles transformed from lamellar structure
to nanostructure during the repeated process of the cold welding and cracking. TEM image reveals clearly that the in-situ
TiC nanoparticles with grain size of 3–8 nm are in the interior of the stainless steel/TiC nanocomposite particles obtained
by ball-milling 100 h.
Funded by the Natural Science Foundation of Hubei Province (No. 2006ABA304) 相似文献
995.
模态语言是讨论关系结构的一种简洁的语言。基本模态语言是仅有一个模态算子◇的模态语言,用ML(◇)表示此语言,但基本模态语言对框架关系的表达力并不是完全的,加入新的模态算子是增强模态语言表达力的方法之一。在基本模态语言ML(◇)基础上增加全局性模态词“E”得到ML(◇,E)语言,这种更丰富的语言对关系模型和关系框架的表达力明显强于基本模态语言。 相似文献
996.
利用火力发电厂中循环水管道与凝汽器之间连接所形成的弯管,首先从弯管流量测量基本理论入手,分别用自由涡流理论和强制涡流理论,建立了循环水在弯管内流动过程中,弯管内外径的压力差与循环水流量之间关系的数学关系模型.其次,利用实验室实验确定循环水流量与弯管内外径之间压差的关系,实现了利用弯管对流体流量进行测量. 相似文献
997.
网格平滑是实现三维模型离散造型的主要方法。为了实现数字人体几何模型的光顺效果,本文提出一种基于Loop细分算法的三维人体模型的网格平滑方法。细分曲面是用低分辨率的控制网格和定义在控制网格上的一种细分规则来表示曲面的,它能有效改善三维人体几何模型的表面不光滑以及分辨率低的缺点。实验证明,该方法对基于参数化建模方法的、多曲率网格人体模型取得了很好的效果,实现简单高效,特征保持效果也很好。 相似文献
998.
Two-dimensional plain-weave silicon carbide fiber fabric reinforced silicon carbide (2D-SiC/SiC) composites were molded by
stacking method and densified through precursor infiltration and pyrolysis (PIP) process. SiC coating was deposited as the
fiber/matrix interphase layer by chemical vapor deposition (CVD) technique. Fiber/matrix debonding and relatively long fiber
pullouts were observed on the fracture surfaces. Additionally, the flexural strength and elastic modulus of the composites
with and without fiber/matrix interphase layer were investigated using three-point bending test and single-edge notched beam
test. The results show that the fiber fraction and the porosity of 2D-SiC/SiC composites with and without coating are 27.2%
(volume fraction) and 11.1%, and 40.7% (volume fraction) and 7.5%, respectively. And the flexural strength and elastic modulus
of 2D-SiC/SiC composites with and without coating are 363.3 MPa and 127.8 GPa, and 180.2 MPa and 97.2 GPa, respectively. With
a proper thickness, the coating can effectively adjust the fiber/matrix interface, thus causing a dramatic increase in the
mechanical properties of the composites.
Foundation item: Project(NCET-07-0228) support by the New Century Excellent Talents in University 相似文献
999.
XU Zhi-wei ZENG Kai-hua WEI Zhou LIU Zhi-qiang ZHAO Xiao-dong TIAN Qiu-hong 《中国矿业大学学报(英文版)》2009,19(1):129-132
Exact calculations of the static earth pressure from a thick alluvium require accurate K0 values. These calculations influence the sinking cost and the safety of the freezing method. The static earth pressure coefficient (K0) of thick and deep soil was analyzed using laboratory tests. The results show that the static earth pressure coefficient of thick and deep soils is nonlinear and different from that of superficial soils. The constant of superficial soils is usually invariant and the total stress or incremental stress definitions used in traditional geo-mechanics give the same value. The influence of load increments when calculating for superficial soil is ignored. The difference in values of K0 for thick alluvium defined by the total stress or the incremental stress methods is over 10%. The effects of the thick alluvium on K0 should be considered during the design of frozen shaft projects. Such things as the frozen shaft thickness and the excavated section height should be chosen to assure the rationality of the design and to avoid potential faults and accidents. 相似文献
1000.
MathML是一个W3C推荐标准.目前,测览器对MathML的支持比较复杂,(X)HTML+MathML存在多种文档方案,这些方案对运行环境往往有一定的要求和限定,为适应多样化应用的需要,必须考虑保留多种文档方案,导致了数据的大量冗余.本文阐述了现有(X)HTML+MathML文档方案的局限性,提出了一种基于JavaScript的HTML+MathML通用方案.该方案使用JavaScript包含MathML,使得同一个HTML+MathML文档能够实现跨平台、跨浏览器、跨插件的应用,简洁实用,有效地解决了通用性的应用需求. 相似文献