排序方式： 共有35条查询结果，搜索用时 15 毫秒
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为有效解决广播式自动相关监视（ADS-B）系统易被人为恶意虚假欺骗这一紧迫问题,提出了一种将全球导航卫星系统（GNSS）完好性信息与ADS-B报文完好性特征属性参数进行一致性比对的自主式防欺骗方法。设计了基于GNSS完好性信息的ADS-B自主式防欺骗算法流程,并利用ADS-B接收机接收的真实报文和模拟产生的虚假报文,对整个防欺骗过程实施了仿真实验。通过对真假ADS-B混合报文的解析,获得时间、位置和导航不确定类别（NUC）的值,根据时间和位置信息利用接收机自主完好性监视（RAIM）和高级接收机自主完好性监视（ARAIM）的完好性增强算法,获得水平保护级（HPL）的预测值,再将该预测值与NUC值进行一致性比对,从而判别ADS-B报文的真实性。仿真结果表明,提出的防欺骗方法能有效防止不含完好性信息或完好性信息与飞机位置不关联的虚假ADS-B报文的恶意欺骗,对虚假报文的识别率不会低于99%。 相似文献
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The progress in atom transfer radical polymerization (ATRP) provides an effective means for the design and preparation of functional membranes. Polymeric membranes with different macromolecular architectures applied in fuel cells, including block and graft copolymers are conveniently prepared via ATRP. Moreover, ATRP has also been widely used to introduce functionality onto the membrane surface to enhance its use in specific applications, such as antifouling, stimuli-responsive, adsorption function and pervaporation. In this review, the recent design and synthesis of advanced functional membranes via the ATRP technique are discussed in detail and their especial advantages are highlighted by selected examples extract the principles for preparation or modification of membranes using the ATRP methodology. 相似文献
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Huang JC 《Scanning》2012,34(4):264-270
This study investigates the surface conditions of silicon wafers with native oxide layers (NOL) or hydrogen passivated layers (HPL) and how they influence the processes of nano-oxidation and wet etching. We also explore the combination of nano-oxidation and wet etching processes to produce nanostructures. Experimental results reveal that the surface conditions of silicon wafers have a considerable impact on the results of nano-oxidation when combined with wet etching. The height and width of oxides on NOL samples exceeded the dimensions of oxides on HPL samples, and this difference became increasingly evident with an increase in applied bias voltage. The height of oxidized nanolines on the HPL sample increased after wet etching; however, the width of the lines increased only marginally. After wet etching, the height and width of oxides on the NOL were more than two times greater than those on the HPL. Increasing the applied bias voltage during nano-oxidation on NOL samples increased both the height and width of the oxides. After wet etching however, the increase in bias voltage appeared to have little effect on the height of oxidized nanolines, but the width of oxidized lines increased. This study also discovered that the use of higher applied bias voltages on NOL samples followed by wet etching results in nanostructures with a section profile closely resembling a curved surface. The use of this technique enabled researchers to create molds in the shape of a silicon nanolens array and an elegantly shaped nanoscale complex structures mold. 相似文献
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Kedage VV Tilak JC Dixit GB Devasagayam TP Mhatre M 《Critical reviews in food science and nutrition》2007,47(2):175-185
Grapes (Vitis vinifera L.) are a major fruit crop in the world. Grapes seem to confer health benefits due to their antioxidant activity. We have evaluated the antioxidant potential of 11 grapes varieties from India and nearby Asian countries. The assays employed involve different levels of antioxidant action like ferric reducing antioxidant power, radical scavenging by 1,1-diphenyl-2-picrylhydrazyl, ferrylmyoglobin/2,2'-azobis-3-ethylbenzthiazoline-6-sulfonic acid, oxygen radical absorbance capacity (ORAC), and inhibition of lipid peroxidation. The total phenolic and flavonoids contents were also estimated. Our study indicates that cv. Mango is the most potent followed by Sharad Seedless. Ethanolic extracts were found to be more effective than aqueous extracts. Cv. Sharad Seedless, Mango, and Manikchaman also had high ORAC values. Their HPLC analysis showed the presence of various antioxidant polyphenols. In conclusion our studies identified some varieties of grapes with high antioxidant activities and showed that their high antioxidant potential may be due to their phenolic and flavonoid contents. 相似文献
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HPL是高性能计算广泛采用的Linpack测试软件包,传统HPL算法中,求解矩阵将以块为单位循环分布到所有处理器,由于国产加速器(China Accelerator)的底层矩阵乘接口仅支持定制接口,传统HPL算法已不适合CPU+China Accelerator异构系统,因此,必须基于定制接口完成矩阵分布细致划分与封装dPEM,以提供一个通用的HPL测试配置环境;同时,为了充分发挥国产异构系统的效率,设计了异构协同矩阵乘调度算法OA4MM,以提高国产异构系统的效率。实验验证了dPEM的有效性和OA4MM算法的高效性,OA4MM较传统的异构HPL调度算法性能提升近10%。 相似文献
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并行集群系统的Linpack性能测试分析 总被引：2，自引：0，他引：2
§1.引言 近些年随着计算机软硬件技术的提高,尤其是网络部件性能的提高,集群技术得到不断的发展。传统的PVP(Parallel Vector Processor)超级计算机以及MPP(Massively Parallel 相似文献
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R. F. Barrett T. H. F. Chan E. F. D'Azevedo E. F. Jaeger K. Wong R. Y. Wong 《Concurrency and Computation》2010,22(5):573-587
This paper describes our effort to enhance the performance of the AORSA fusion energy simulation program through the use of high‐performance LINPACK (HPL) benchmark, commonly used in ranking the top 500 supercomputers. The algorithm used by HPL, enhanced by a set of tuning options, is more effective than that found in the ScaLAPACK library. Retrofitting these algorithms, such as look‐ahead processing of pivot elements, into ScaLAPACK is considered as a major undertaking. Moreover, HPL is configured as a benchmark, but only for real‐valued coefficients. We therefore developed software to convert HPL for use within an application program that generates complex coefficient linear systems. Although HPL is not normally perceived as a part of an application, our results show that the modified HPL software brings a significant increase in the performance of the solver when simulating the highest resolution experiments thus far configured, achieving 87.5 TFLOPS on over 20 000 processors on the Cray XT4. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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基于HPL测试的集群系统性能分析与优化 总被引：1，自引：0，他引：1
集群系统以很高的性价比和良好的可扩展性而成为当今高性能研究的一大新熟点,如何评价与优化集群系统的特性也成为一个很关键的问题。本文通过采用全世界TOP500计算机排名所用的HPL基准测试,对集群的浮点运算性能进行评测和分析,根据在集群系统上进行的HPL基准测试的结果分析总结了影响其整体性能的重要因素,并对这些方面一一给出具体的分析,提出了针对集群系统具有实际意义和研究价值的优化方向和优化方法。 相似文献