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Chiani M. Win M.Z. Zanella A. Winters J.H. 《Wireless Communications, IEEE Transactions on》2004,3(1):12-16
We derive a simple closed-form upper bound on the symbol error probability for coherent detection of M-ary phase-shift keying using antenna arrays with optimum combining, in the presence of multiple uncorrelated equal-power cochannel interferers and thermal noise in a Rayleigh fading environment. The new bound, based on Laguerre polynomials, is valid for an arbitrary number of antenna elements as well as arbitrary number of interferers, and it is proven to be asymptotically tight. Comparisons with Monte Carlo simulation are also provided, showing that our bound is useful in many cases of interest. 相似文献
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The dependences of both oxidation-resistant and self-aligned silicidation properties on the thicknesses of top amorphous-Si (a-Si) and Ti metal in an a-Si/Ti bilayer process are presented. It is shown that a thin silicide layer formed during the reaction between a-Si and Ti films becomes a stable oxidation and nitridation barrier for oxygen- and nitrogen-related impurities. Moreover, the formation sequence of the silicide phase depends not only on the annealing temperature but also on the thickness of the Ti film. In addition, the preferential orientation of the silicide phase after annealing at high temperature also shows a strong dependence on the thickness of Ti film, which is attributed to the difference of the grain size in the polycrystalline silicide film. The allowed process window for the a-Si thickness can be determined experimentally and a reproducible and homogeneous self-aligned TiSi2 film can be easily obtained by using the a-Si/Ti bilayer process in salicide applications despite high-level contaminations of oxygen impurities in both the as-deposited Ti film and the annealing ambient 相似文献
5.
Joe A. Potter Gareth W. Price Chelsy L. Cliff Colin R. Green Paul E. Squires Claire E. Hills 《International journal of molecular sciences》2021,22(7)
Chronic Kidney Disease (CKD) is associated with sustained inflammation and progressive fibrosis, changes that have been linked to altered connexin hemichannel-mediated release of adenosine triphosphate (ATP). Kidney fibrosis develops in response to increased deposition of extracellular matrix (ECM), and up-regulation of collagen I is an early marker of renal disease. With ECM remodeling known to promote a loss of epithelial stability, in the current study we used a clonal human kidney (HK2) model of proximal tubular epithelial cells to determine if collagen I modulates changes in cell function, via connexin-43 (Cx43) hemichannel ATP release. HK2 cells were cultured on collagen I and treated with the beta 1 isoform of the pro-fibrotic cytokine transforming growth factor (TGFβ1) ± the Cx43 mimetic Peptide 5 and/or an anti-integrin α2β1 neutralizing antibody. Phase microscopy and immunocytochemistry observed changes in cell morphology and cytoskeletal reorganization, whilst immunoblotting and ELISA identified changes in protein expression and secretion. Carboxyfluorescein dye uptake and biosensing measured hemichannel activity and ATP release. A Cytoselect extracellular matrix adhesion assay assessed changes in cell-substrate interactions. Collagen I and TGFβ1 synergistically evoked increased hemichannel activity and ATP release. This was paralleled by changes to markers of tubular injury, partly mediated by integrin α2β1/integrin-like kinase signaling. The co-incubation of the hemichannel blocker Peptide 5, reduced collagen I/TGFβ1 induced alterations and inhibited a positive feedforward loop between Cx43/ATP release/collagen I. This study highlights a role for collagen I in regulating connexin-mediated hemichannel activity through integrin α2β1 signaling, ahead of establishing Peptide 5 as a potential intervention. 相似文献
6.
Cliff Tubbe 《橡胶工业》2002,49(2):104-105
为满足用户日新月异的需求 ,多年来人们致力于挤出机技术的改进工作。最简单的就是热喂料挤出机 ,它最多只能称作是在一个圆筒内工作的阿基米德螺杆 ,通常用来将没有定型的不连续的胶料制成一定横截面和尺寸均一的连续胶条。但是不能小看这种装置 ,这种古老的热喂料挤出机是很有用的 ,它可以生产轮胎零部件和其它许多工业橡胶制品 ,包括胶带和胶管。至今仍有许多热喂料挤出机在使用中。冷喂料挤出机代替热喂料挤出机有几个很重要的原因 ,其中之一就是热喂料挤出机要求母炼胶充分预热 ,而热炼机费用极为昂贵 ,而且这些价格不菲的庞大装置占地… 相似文献
7.
Dalaijargal Purevsuren Saif ur Rehman Gang Cui Jianmin Bao Nwe Nwe Htay Win 《哈尔滨工业大学学报(英文版)》2015,22(6):76-84
As the number of objectives increases, the performance of the Pareto dominance-based Evolutionary Multi-objective Optimization (EMO) algorithms such as NSGA-II, SPEA2 severely deteriorates due to the drastic increase in the Pareto-incomparable solutions. We propose a sorting method which classifies these incomparable solutions into several ordered classes by using the decision maker's (DM) preference information. This is accomplished by designing an interactive evolutionary algorithm and constructing convex cones. This method allows the DMs to drive the search process toward a preferred region of the Pareto optimal front. The performance of the proposed algorithm is assessed for two, three, and four-objective knapsack problems. The results demonstrate the algorithm's ability to converge to the most preferred point. The evaluation and comparison of the results indicate that the proposed approach gives better solutions than that of NSGA-II. In addition, the approach is more efficient compared to NSGA-II in terms of the number of generations required to reach the preferred point. 相似文献
8.
Cliff Miller 《程序员》2010,(9):59-59
MeeGo,正在成为移动直联网领域的一颗新星。
在今年2月的世界3GSM大会上,诺基亚与英特尔一起宣布了新一代专门针对移动终端的智能操作平台——MeeGo的诞生。MeeGo是英特尔的Moblin与诺基亚的Maemo的组合体,是为下一代计算设备打造的基于Linux系统的开源软件平台,它完全开放源代码,能够将服务、内容与用户体验相结合,为消费者带来全新的移动互联的操作体验。目前MeeGo由国际非盈利性组织Linux基金会进行管理。 相似文献
9.
As part of the Bristol Wearable Computing Initiative, we are exploring location-sensing systems suitable for use with wearable
computing. In this paper we present our findings, and in particular a wearable application — the ‘Shopping Jacket’ — which
relies on a minimal infrastructure to be effective. We use two positioning devices, ‘pingers’ and GPS. The pinger is used
to signal the presence of a shop, and to indicate the type of shop and its website. The GPS is used to disambiguate which
branch of a high street chain is being passed. The wearable uses this information to determine whether the wearer needs to
be alerted that they are passing an interesting shop, or to direct the wearer around a shopping mall. The Shopping Jacket
integrates a wearable CardPC, GPS and pinger receivers, a near-field radio link, hand-held display, GSM data telephone and
a speech interface into a conventional sports blazer. 相似文献
10.
A realization problem for a class of linear hereditary systems is formulated and state space representations are constructed from inputoutput relations. The resulting hereditary models are shown to be Euclidean controllable, and comparisons are made between these hereditary realizations and other recently developed theories.This research was supported in part by the Air Force Flight Dynamics Laboratory under grant AFOSR-77-3221. 相似文献