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941.
中巴地球资源一号卫星红外多光谱扫描仪、交叉定标方法研究 总被引:2,自引:3,他引:2
建立CBERS—1上搭载的红外多光谱扫描仪(IRMSS)与FY—1C通道4及Landsat-7上ETM 波段6多星星载热红外遥感仪器交叉定标的算法模型,利用美国Landsat-7上搭载的ETM 红外通道6和FY—1C通道4分别对IRMSS热红外通道进行交叉定标,得到二组定标结果.相同地标点对比分析结果表明,二个定标结果得到的目标点亮度温度相对偏差为1.2K;IRMSS交叉定标结果与Landsat-7ETM 热红外通道在轨定标结果独立样本对比分析结果,均方根偏差为1.6K. 相似文献
942.
943.
为了解决传统的煤矿监控系统存在的信息孤岛和被动监视的问题,本文提出了一种基于物联网的煤矿检测监控系统。系统主要由基于嵌入式平台的井下人员终端、环境检测设备、ZigBee路由器和ZigBee协调器、服务器、监控中心组成。在通讯协议上,采用Zigbee协议和高层自定义协议,使各组成部分之间实现了互联互通。本系统具有结构简单、工作可靠、便于维护等特点,对于我国矿井安全监测监控系统的现代化改造,提高矿井生产效率和经济效益具有重要意义。 相似文献
944.
针对现有的高光谱图像压缩感知重构算法对图像的空谱特性利用不够充分,导致重构图像质量不够高的问题,提出了一种高光谱图像变投影率分块压缩感知结合优化谱间预测重构方案。编码端以频段聚类方式将高光谱图像的所有频段分成参考频段和普通频段,对不同频段单独采用不同精度分块压缩感知以获取高光谱数据。在解码端,参考频段直接采用稀疏度自适应匹配追踪( SAMP)算法重构,对于普通频段,则设计了一种优化谱间预测结合SAMP算法的新模型进行重构:首先通过重构的参考频段双向预测普通频段,并对其进行压缩投影,然后计算预测前后普通频段投影值的残差,最后利用SAMP算法重构该残差,以此修正预测值。实验表明,相比同类算法,该算法充分考虑了高光谱图像的空谱特性,有效改善了重构图像质量,且编码复杂度低,易于硬件实现。 相似文献
945.
946.
In January 2010, the State Council of China decided to speed up the convergence of the telecommunications network, cable network and Internet network. That means the government led practical exploration of the networks convergence. The convergence is related to the entities in the fields of telecommunications, broadcasting and the Internet industry. The authors apply the static game theory to analyze the games among the players in the fields of telecommunications and broadcasting, and point out that the games would strengthen the network infrastructures, promote the development of related industries, and profoundly influence and change the ways of thinking and social management in China. At last, the paper puts forward some policy recommendations. 相似文献
947.
Qunwei Tang Xiaoming Sun Qinghua Li Jihuai Wu Jianming Lin 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,346(1-3):91-98
Hydrogels have potential applications in many fields, but the poor mechanical strength has limited their further development. In this article, we designed a high-strength hydrogel with an interpenetrating network (IPN) structure from polyacrylamide (PAM) and poly(vinyl alcohol) (PVA). Synthesis parameters, such as PVA/AM mass ratio, crosslinker dosage and elongation time were carried out for high tensile strength and elongation. The results showed that chemical crosslinking, physical entanglement and PVA precipitates were the dominant parameters for the improvement of mechanical properties. The PVA structure transferred from crystal to amorphous due to intermolecular and intramolecular interactions (such as hydrogen bond and self-crosslinking). PVA precipitates scatterred in the brittle PAM matrix homogeneously which dispersed the applied stress and improved the hydrogel toughness. The tensile strength and elongation were extremely high, they were 2.4 MPa and 3100%, respectively. The simple method is versatile in synthesizing high-strength IPN hydrogels using many kinds of polymer species. 相似文献
948.
In this work, we present the modeling of the peak deceleration (PD) using data of the experimental drop test. Specimens with different thicknesses and areas tested in the drop test device which has adaptable height and weight. In the empirical modeling of the PD, the thickness, area, drop mass and drop height considered as separable functions. An analytical model and Neural Network (NN) was used as the empirical models. Further, the stress on the material was calculated using differential equations and the Finite Element Method (FEM). The Obtained PD from the experimental test, analytical and NN models was converted to the stress on the material using a derived differential equation. Finally, the best model for analyzing the PD and Stress on the material was presented. 相似文献
949.
Han Zhang Zhi-Yang Yan Yu-Xi Wang Ming Bai Xiao-Bo Wang 《Natural product research》2019,33(16):2368-2371
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder associated with synaptic dysfunction, pathological accumulation of β-amyloid (Aβ), and neuronal loss. Given the prevalence of AD and the lack of effective long-term therapies, there is a pressing need to discover viable leads that can be developed into clinically approved drugs with disease-modifying effects. The analysis of current reported literatures confirms the importance of the plants of Pithecellobium genus as candidate against AD. Hence, it is necessary to identify selective anti-dementia agents from this genus. To explore potential compounds with marked effect on AD in Pithecellobium genus, a compound database based on the methods of network pharmacology prediction was established in this paper by constructing the compound-disease target network. The result showed that the most effective compound in the plants of this genus might be (7′R,8′R)-7′-methoxyl strebluslignanol, and the most potential target might be Macrophage colony-stimulating factor 1 receptor. 相似文献
950.
《International journal of quantum chemistry》2018,118(3)
A global potential energy surface (PES) corresponding to the ground state of AuH2 system has been constructed based on 22 853 ab initio energies calculated by the multireference configuration interaction method with a Davidson correction. The neural network method is used to fit the PES, and the root mean square error is only 1.87 meV. The topographical features of the novel global PES are compared with previous PES which is constructed by Zanchet et al. (Zanchet PES). The global minimum energy reaction paths on the two PESs both have a well and a barrier. Relative to the Au + H2 reactants, the energy of well is 0.316 eV on the new PES, which is 0.421 eV deeper than Zanchet PES. The calculation of Au(2S) + H2(X1Σg+) → AuH(X1Σ+) + H(2S) dynamical reaction is carried out on new PES, by the time‐dependent quantum wave packet method (TDWP) with second order split operator. The reaction probabilities, integral cross‐sections (ICSs) and differential cross‐sections are obtained from the dynamics calculation. The threshold in the reaction is about 1.46 eV, which is 0.07 eV smaller than Zanchet PES due to the different endothermic energies on the two PESs. At low collision energy (<2.3 eV), the total ICS is larger than the result obtained on Zanchet PES, which can be attributed to the difference of the wells and endothermic energies. 相似文献