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71.
通过检测原子团离于MCs 和MAs-(M是基体元素)对AlxGa1-xAs基体组分进行了定量的分析,考察了MIQ-156SIMS上所测这些原子团离子的能量分布及其对分析结果的影响,并对正、负SIMS测量方法做出比较。 相似文献
72.
73.
1.5 mu m band travelling-wave semiconductor optical amplifiers (TWAs), characterised by their window facet structure and symmetrised active waveguide, have been developed. 1.5 dB spectral gain ripple and 1.3 dB TE-TM mode gain difference at 22 dB signal gain were achieved simultaneously. An average facet reflectivity as low as 0.06% was estimated.<> 相似文献
74.
介绍油田普遍使用的一种测井方法-微球形聚焦测井。它用于测量地层冲洗带电阻率。文中还介绍了微球形聚焦测井仪在使用过程中所出现问题解决的措施,并提出了在测井仪器选用中的一种思路-强强联合。经技术改造后的仪器,在现场应用,取得Rxo、Rmc,dH三条全优曲线,取得较好的效果。 相似文献
75.
Suk-Keun Cha Jeong-Hoon Lee Joon Jae Yoo Jung Hoon Kang Han Gyu Kim Dong Hoon Kim Jun Yeob Song 《测试科学与仪器》2010,(Z1):192-198
<正>The first tier of automotive manufacturers has faced to pressures about move,modify,updating tasks for manufacturing resources in production processes from demand response of production order sequence for motor company and process innovation purpose for productivity. For meets this requirements,it has to require absolutely lead time to re-wiring of physical interface for production equipment,needs for change existing program and test over again.For prepare this constraints,it needs studying an auto-configuration functions that build for both visibility and flexibility based on the 4M(Man,Machine,Material, Method)group management which is supports from WSN (Wireless Sensor Network)of the open embedded device called M2M(Machine to Machine)and major functions of middleware including point manager for real-time device communication,real-time data management,Standard API (Application Program Interface)and application template management.To be application system to RMS (Reconfigurable Manufacturing System)for rapidly response from various orders and model from motor company that is beginning to establishing the mapping of manufacturing resources of 4M using WSN. 相似文献
76.
Artemisia lavandulaefolia has been utilized in traditional medicines for the treatment of several diseases. In this study, we attempted to determine
whether the essential oil and 1,8-cineole of A. lavandulaefolia induce apoptosis in KB cells. The oil and 1,8-cineole induced the cell death of KB cells as evidenced by the increased cell
population in the sub-G1 phase, the appearance of condensed and/or fragmented nuclei, and the generation of a cleaved PARP
product. The treatment of the cells with the oil also induced changes in the mitochondrial level of Bcl-2 and Bax, thereby
inducing the release of cytochrome c into the cytosol. Furthermore, the oil increased the phosphorylation of extracellular signal-regulated kinase (ERK), c-jun
N-terminal kinase, and p38 MAPK, but 1,8-cineole activated pp38 and pJNK at the same concentrations. These findings show that
the mitochondrial and MAPKs pathways might be involved in the oil-induced apoptosis, and may enhance our current understanding
of the anticancer functions of the oil to a greater degree than 1,8-cineole. 相似文献
77.
本文阐述了构建安全体系结构的意义,以及安全体系结构所包括的主要内容.重点以企业网为例介绍了应当如何根据自身实际,以安全体系为指导,构建其安全防护体系. 相似文献
78.
本文对在填困区一和布克赛尔县沙尔布尔山地区发现的铜矿化点的地质概况、矿物组合及地化元素组合特征进行了初步研究,并对矿化规律及矿化标志提出了认识,为今后进一步开展找矿工作提供依据. 相似文献
79.
察可文 《山东轻工业学院学报》1989,(Z2)
对于重积分的计算(主要是二重积分和三重积分的计算),在《数学分析》和《高等数学》的教科书中都有讲述。本文提出一种不用画几何图形而用解不等式组的代数方法,此法对n(n≥3)重积分和变更单积分的顺序更为有效。 相似文献
80.
Cha Zhang Jin Li 《Multimedia, IEEE Transactions on》2005,7(6):1170-1182
In this paper, we describe a system for wandering in a realistic environment over the Internet. The environment is captured by the concentric mosaic, compressed via the reference block coder (RBC), and accessed and delivered over the Internet through the virtual media (Vmedia) access protocol. One of the key contributions of the paper is the proposal of the RBC concentric mosaic coder. The RBC coder not only compresses the huge dataset of the concentric mosaic very efficiently, but also produces a well-organized bitstream that can be accessed just-in-time (JIT). To reconstruct a virtual view, only a portion of the RBC bitstream needs to be accessed and decoded. This greatly reduces the memory and computation requirement of the viewer compared with first decoding the entire concentric mosaic data set and then rendering from the decoded data. Our second contribution is the employment of the Vmedia protocol to deliver the compressed concentric mosaic bitstream just-in-time over the Internet. Only the bitstream segments corresponding to the current view are streamed over the Internet. The delivered bitstream segments are managed by a local Vmedia cache, so that frequently used bitstream segments do not need to be streamed over the Internet repeatedly, and a RBC bitstream larger than the memory capacity can be easily handled. Combining RBC and Vmedia, a concentric mosaic interactive browser is developed through which the user can freely wander in a realistic environment, e.g., rotate around, walk forward/backward, and sidestep, even under a tight bandwidth. 相似文献