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11.
Aykut Avci Jan De CockPeter Lambert Roel BeernaertJelle De Smet Lawrence BogaertYouri Meuret Hugo ThienpontHerbert De Smet 《Journal of Visual Communication and Image Representation》2012,23(2):287-292
An efficient disparity estimation algorithm for multi-view video sequences, recorded by a two-dimensional camera array in which the cameras are spaced equidistantly, is presented. Because of the strong geometrical relationship among views, the disparity vectors of a certain view can for most blocks be derived from the disparity vectors of other views. A frame constructed using that idea is called a D frame in this work. Three new prediction schemes which contain D frames are proposed for encoding 5 × 3 multi-view video sequences. The schemes are applied to several multi-view image sequences taken from a camera-array and they are compared in terms of quality, bit-rate and complexity. The experimental results show that the proposed prediction schemes significantly decrease the complexity of the encoder at a very low cost of quality and/or bit-rate. 相似文献
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本文的主要针对基于ZigBee的温室大棚环境监控硬件系统需求,构建无线传感器网络的节点端、中间件和客户端,使用Lab VIEW平台开发监控系统客户端界面,在Mote Works中开发一些自组网技术的节点端,负责对传感器采集的到的一些数据进行存储转发,而中间件是由Xserve去实现并对组建的模拟系统进行测试。 相似文献
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“内容中心网络”(Content Centric Networking,CCN)是未来互联网架构体系群中极具前景的架构之一。CCN的核心思想在于内容命名,即用户不需要根据数据的地址而仅根据数据的名字来获取目标内容。在设计上,CCN是一种基于拉(pull-based)的网络,即用户为了获取相应的内容,必须向网络发送一个兴趣包(Interest)以便获取同名数据包(Data),也就是说CCN是一个用户驱动的网络。安全对任何一种网络架构来说,都是不容忽视的一个问题,其中,拒绝服务攻击(DoS)是TCP/IP网络中最为常见的攻击手法之一,这里研究了CCN中常见的DoS攻击,并提出了具有针对性的解决方案。 相似文献
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Mahmoud Emam Doaa R. Abdel-Haleem Maha M. Salem Lina Jamil M. Abdel-Hafez Rasha R. Abdel Latif Shaimaa Mahmoud Farag Mansour Sobeh Mohamed A. El Raey 《Molecules (Basel, Switzerland)》2021,26(6)
Infections associated with the emergence of multidrug resistance and mosquito-borne diseases have resulted in serious crises associated with high mortality and left behind a huge socioeconomic burden. The chemical investigation of Lavandula coronopifolia aerial parts extract using HPLC–MS/MS led to the tentative identification of 46 compounds belonging to phenolic acids, flavonoids and their glycosides, and biflavonoids. The extract displayed larvicidal activity against Culex pipiens larvae (LC50 = 29.08 µg/mL at 72 h). It significantly inhibited cytochrome P-450 monooxygenase (CYP450), acetylcholinesterase (AChE), and carboxylesterase (CarE) enzymes with the comparable pattern to the control group, which could explain the mode of larvae toxification. The extract also inhibited the biofilm formation of Pseudomonas aeruginosa by 17–38% at different Minimum Inhibitory Concentrations (MICs) (0.5–0.125 mg/mL) while the activity was doubled when combined with ciprofloxacin (ratio = 1:1 v:v). In conclusion, the wild plant, L. coronopifolia, can be considered a promising natural source against resistant bacteria and infectious carriers. 相似文献
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Abdirahman Elmi Fatouma Mohamed Abdoul-Latif Rosella Spina Franois Dupire Stphanie Philippot Champy Marie-France Hugues Jacobs Dominique Laurain-Mattar 《Molecules (Basel, Switzerland)》2021,26(10)
For the first time, the study of the antioxidant activity, the characterization of the phytoconstituants, and the evaluation of in vitro and in vivo toxicity of A. djiboutiensis leave and latex are performed. The antioxidant activity of both latex (ADL) and the methanolic extract of leaves (ADM) is determined using 1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) scavenging radical methods and ferric reducing/antioxidant power (FRAP) assay. The phytochemical study of latex is done using Liquid Chromatography-Mass Spectrometry (LC-MS/MS) and a molecular networking-based approach. The evaluation of in vivo toxicity is performed on mice by oral gavage with a suspension of ADL. Our results show that weak antioxidant activity of ADL and ADM in opposition to their high polyphenol, 83.01 mg and 46.4 mg expressed in gallic acid equivalent (GAE)/g of dry weight (DW), respectively, and flavonoid contents 13.12 mg and 4.25 mg expressed in quercetin equivalent (QE)/g dry weight (DW), respectively. Using the Global Natural Products Social Molecular Networking (GNPS) website, nine (9) anthraquinones derivatives, ten (10) chromones derivatives, two (2) flavonols/ chromones isomers are annotated in the molecular network. The treated mice do not display abnormalities in their general physical appearance and biochemistry parameters, compared to the controls. Only glucose and calcium levels are slightly higher in male treated mice compared to the vehicles. 相似文献
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This paper presents a novel parallel processing-based frame synchronous methodology for 155·520 Mbit/s high speed networks according to ITU-T Recommendations G.707, G.708 and G.709. This scheme is expected to relax operating speed requirements of the circuits used in the system. The proposed methodology can be implemented using off-the-shelf low-rate integrated circuits (ICs). The performance of the devised methodology is analysed and found to be similar to that of traditional approaches. Finally, the proposed scheme is efficient and easy to implement at low cost without sacrificing performance. 相似文献