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21.
针对视频序列拼接中容易造成拼接耗时较长、拼接效果不佳等问题,提出一种有效的视频序列拼接方法,首先,利用时域检测窗口对视频序列进行关键帧的提取,其次,利用相邻关键帧间特征点的匹配结合(random sample consensus)算法以及单应矩阵的级联特性,获取相邻关键帧和非相连关键帧间的匹配矩阵,最后通过融合实现了关键帧所表示的视频序列无缝拼接,效果比较理想。  相似文献   
22.
文中详细讨论了Java语言在处理汉字时所存在的问题,给出了解决问题的方案,实现了Unicode字符集与汉字内码字集的相互转换的Java类。  相似文献   
23.
吴向成  徐艳芬 《电视技术》2012,36(23):124-125,150
主要利用网管设计实现对集成了光时域反射仪(OTDR)板卡的OLT设备进行管理,达到监控管理光链路状况的目的。该方案具有自动检测和手动检测的功能,图形化的界面能实时显示测试与诊断结果。检测过程更简单,采集手段更完善,测试结论更准确,具有很强的实时性和实用性。  相似文献   
24.
研究了La掺杂PZST反铁电陶瓷在不同偏置电场下的场诱热释电特性。在0~120°C温度范围内,热释电的峰值和峰位可以用电场的大小来控制,热释电系数达到10-7C/cm2·K。  相似文献   
25.
A closed form expression for the bit error rate (BER) performance of frequency domaindifferential demodulation(FDDD) for orthogonal frequency division multiplexing system in flat fadingchannel is derived.The performance is evaluated by computer simulation and compared with the timedomain differential demodulation(TDDD).The results indicate that the performance of FDDD is betterthan that of TDDD,and the lower band of BER in the former is lower than that of the latter.  相似文献   
26.
Influenza viruses are transmitted from human to human via airborne droplets and can be transferred through contaminated environmental surfaces. Some works have demonstrated the efficacy of essential oils (EOs) as antimicrobial and antiviral agents, but most of them examined the liquid phases, which are generally toxic for oral applications. In our study, we describe the antiviral activity of Citrus bergamia, Melaleuca alternifolia, Illicium verum and Eucalyptus globulus vapor EOs against influenza virus type A. In the vapor phase, C. bergamia and M. alternifolia strongly reduced viral cytopathic effect without exerting any cytotoxicity. The E. globulus vapor EO reduced viral infection by 78% with no cytotoxicity, while I. verum was not effective. Furthermore, we characterized the EOs and their vapor phase by the head-space gas chromatography–mass spectrometry technique, observing that the major component found in each liquid EO is the same one of the corresponding vapor phases, with the exception of M. alternifolia. To deepen the mechanism of action, the morphological integrity of virus particles was checked by negative staining transmission electron microscopy, showing that they interfere with the lipid bilayer of the viral envelope, leading to the decomposition of membranes. We speculated that the most abundant components of the vapor EOs might directly interfere with influenza virus envelope structures or mask viral structures important for early steps of viral infection.  相似文献   
27.
COVID-19, resulting from infection by the SARS-CoV-2 virus, caused a contagious pandemic. Even with the current vaccines, there is still an urgent need to develop effective pharmacological treatments against this deadly disease. Here, we show that the water and ethanol extracts of the root and rhizome of Polygonum cuspidatum (Polygoni Cuspidati Rhizoma et Radix), a common Chinese herbal medicine, blocked the entry of wild-type and the omicron variant of the SARS-CoV-2 pseudotyped virus into fibroblasts or zebrafish larvae, with IC50 values ranging from 0.015 to 0.04 mg/mL. The extracts were shown to inhibit various aspects of the pseudovirus entry, including the interaction between the spike protein (S-protein) and the angiotensin-converting enzyme II (ACE2) receptor, and the 3CL protease activity. Out of the chemical compounds tested in this report, gallic acid, a phytochemical in P. cuspidatum, was shown to have a significant anti-viral effect. Therefore, this might be responsible, at least in part, for the anti-viral efficacy of the herbal extract. Together, our data suggest that the extracts of P. cuspidatum inhibit the entry of wild-type and the omicron variant of SARS-CoV-2, and so they could be considered as potent treatments against COVID-19.  相似文献   
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29.
The entire gene of carboxyltransferase(CT) domain of acetyl-CoA carboxylase(ACCase) from Chinese Spring wheat(CSW) plastid was cloned firstly,and the 2.3 kb gene was inserted into PET28a+ vector and expressed in E.coil in a soluble state.The (His)6 fusion protein was identified by SDS-PAGE and Western blot.The recombinant protein was purified by affinity chromatography,and the calculated molecular mass(Mr) was 88000.The results of the sequence analysis indicate that the cloned gene(GeneBank accession No.EU124675) was a supplement and revision of the reported ACCase CT partial cDNA from Chinese Spring wheat plastid.The recombinant protein will be significant for us to investigate the recognizing mechanism between ACCase and herbicides,and further to screen new herbicides.  相似文献   
30.
为了提升对集群无人机目标的分辨能力,提出了一种波束域方位超分辨估计算法。该方法不仅可以避免传统的稀疏表示类测角方法的计算复杂度高和需要选取超参数问题,而且在单快拍数、入射信号空间角度间隔较小等非理想情况下都具备很好的分辨能力,与相控阵雷达波束形成、距离?多普勒域处理的流程相适配。通过仿真试验,可以说明:该方法可以帮助雷达提前将密集目标分辨开,进而实现对于集群的规模(个数)、轮廓等信息进行准确估计,具有很强的应用价值。  相似文献   
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