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111.
基于无线传感器网络的粮虫声信号采集系统设计 总被引:7,自引:2,他引:5
为了解决现有储粮害虫声信号采集系统存在的扩展性差、智能化程度不高、性价比较低、灵活性不强、数据传输能力较弱等问题,该文分析了现有储粮害虫声信号采集系统存在的局限性,在此基础上,利用无线传感器网络和压缩感知技术,设计了一种新型储粮害虫声信号采集系统,给出了系统结构和软硬件实现方法,并将其用于采集储粮罐内赤拟谷盗成虫的爬行声。试验结果表明,系统设计方案合理可行,且由于使用了压缩感知技术,在采样频率为10 KHz的情况下,可实现20个采集节点所产生的声信号原始采样数据的远程、实时、可靠无线传输。该研究为无线传感器网络在储粮害虫防治中的应用做出了探索。 相似文献
112.
基于神经网络预测的无线传感器网络田间射频信号路径损耗 总被引:2,自引:2,他引:0
为解决应用无线传感器网络技术监测农田信息时无法快速预测射频信号路径损耗的问题,基于神经网络理论研究了田间路径损耗与其影响因素间的关系。试验中选取915和2 470 MHz 2个载波频率,在冬小麦的不同生长阶段测量射频信号在田间各影响因素作用下的路径损耗,建立和验证基于神经网络的射频信号田间路径损耗预测模型。所建立模型模拟值与实测值的相关系数为0.92,应用建立的神经网络预测田间射频信号路径损耗并与实测值对比,最大预测误差绝对值为4.186 dB,最大预测标准差为2.759 dB,预测准确度为94.2%。所建立的BP网络可以对田间射频信号路径损耗进行预测。 相似文献
113.
G-protein-coupled receptor kinases (GRKs) are a family of serine/threonine protein kinases. The investigators pay much attention to the roles of GRKs in the signal transduction through G-protein-coupled receptors (GPCRs) with arrestin ever since a long time ago. Due to the physiological and pathological observations with the methods of deletion or overexpression, GRKs are considered as new drug targets. The kinases play a role in the pathogenesis of hypertension and cell migration through GPCRs and Hedgehog signaling pathways. As the development of research techniques, especially bioluminescence resonance energy transfer (BRET) and fluorescence resonance energy transfer (FRET), the special mechanism of GRKs for GPCRs is more evident. In this review, we discuss the recent achievement in the roles of GRKs signaling and the related newest research techniques. 相似文献
114.
钙调磷酸酶-活化T细胞核因子信号途径在骨骼肌细胞生长和发育中生理作用的研究进展 总被引:1,自引:0,他引:1
钙调磷酸酶-活化T细胞核因子(nuclear factor of activated T cells,NFAT)信号途径作为肌肉细胞内重要的生物信号转导途径,在肌肉细胞中起到调节枢纽的作用,与肌肉生长及肌纤维的类型有密切关系.而肌肉组织降解在动物肌肉嫩化过程中具有重要的意义.因此,钙调磷酸酶-NFAT信号途径可能与肌肉... 相似文献
115.
The hemibiotrophic fungus Colletotrichum orbiculare forms appressoria as infection structures and primarily establishes biotrophic infection in cucumber epidermal cells. Subsequently, it develops necrotrophic infection. In the pre-invasion stage, morphogenesis of appressoria of C. orbiculare is triggered by signals from the plant surface. We found that C. orbiculare PAG1 (Perish-in-the-Absence-of-GYP1), a component of MOR [morphogenesis-related NDR (nuclear Dbf2-related) kinase network] plays an essential role as a key component of the plant-specific signaling pathway and that hydrolysis of cutin by a spore surface esterase creates a cutin monomer that constitutes a key plant-derived signal. Development of the infection structure of C. orbiculare is strictly regulated by the cell cycle and we found that proper regulation of G1/S progression via two-component GAP genes, consisting of BUB2 (Budding-Uninhibited-by-Benomyl-2) and BFA1 (Byr-Four-Alike-1) is essential for the establishment of successful infection. In the post-invasion stage, the establishment of the biotrophic phase of hemibiotrophic fungi is crucial for successful infection. We found that C. orbiculare WHI2 (WHIsky-2), an Saccharomyces cerevisiae stress regulator homolog, is involved in the phase transition from biotrophy to necrotrophy through TOR (Target of Rapamycin) signaling, and is thus essential for full pathogenesis. 相似文献
116.
Notch信号通路是一条进化上十分保守的信号转导系统,在调节干细胞增殖、分化和凋亡方面起到重要作用。研究表明,鹿生茸区骨膜和角柄骨膜分别含有鹿茸发生和再生的干细胞。应用RT-PCR的方法对离体培养生茸区骨膜和角柄骨膜细胞进行检测,得出Notch信号通路各信号因子在2种细胞中的表达情况。结果:Notch-1、Notch-2、Notch-4、Dll-4J、agged-1J、agged-2、Hes-1等信号因子在这2种干细胞中均有不同程度的表达,说明Notch信号通路可能参与了他们的增殖、分化的调控。 相似文献
117.
CAI Jing zhi 《保鲜与加工》2003,(4):93-95
With the development and application of information and internet and virtual instrument technology ,the virtual globular company based on internet arises .To study remote state monitoring, remote fault detection and diagnosis about large scale, complicated and integrative equipment become very important. In the whole fault diagnosis system , the detecting ,data acquisition is original ,processing; transform and extracting features with the signal detected is a key factor. The theories and methods used in mechanical fault diagnosis is stated. The application of signal process and its feature extracting methods is introduced which are time domain, frequency domain and time frequency domain analysis, in state monitoring and fault diagnosis with its signal analysis. The processing method of random time variant special signal is given also. 相似文献
118.
119.
论述了监控系统图象信号传输中同轴电缆、双绞线和光纤的特点和传输特性,并对其技术性能进行了分析。 相似文献
120.
LIU Lian YU Rong-jie DAI Yun ZENG Zhi-xing GUO Xiao-ling JI Qing-shan ZHONG Jing-xiang 《园艺学报》2015,31(1):135-140
AIM: To construct the prokaryotic expression system containing protein transduction domain (PTD) with heat shock protein 27 (HSP27) in order to prepare and purify the recombinant protein, and to verify whether the recombinant protein PTD-HSP27 has the ability to penetrate the human lens epithelial cell (HLEC) membrane and the rabbit cornea. METHODS: The plasmid pKYB-PTD-HSPB1-6His was constructed by the technique of overlap extension PCR. The plasmid was transformed and PTD-HSP27 was purified through nickel affinity chromatography column and identified by Western blotting. PTD-HSP27-6His was labeled with the fluorescein isothiocyanate (FITC). The penetrating ability of PTD-HSP27 into HLECs and rabbit cornea was tested. RESULTS: The recombinant PTD-HSP27 plasmid was successfully cloned and effectively expressed. The correctness of the recombinant protein PTD-HSP27 was demonstrated. Fluorescence microscopic examination showed that PTD-HSP27-FITC was internalized by HLECs. Fluorescent labeled PTD-HSP27 was then observed in the rabbit aqueous humor. CONCLUSION: The recombined gene PTD-HSPB1 was constructed by overlap extension PCR technique and the PTD-HSP27 fusion protein was prepared and purified by nickel affinity chromatography column. Using the technique of PTD-fusion protein, HSP27 was transduced into HLECs and passed through the cornea. 相似文献