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1.
基于深度学习的图像超分辨率算法通常采用递归的方式或参数共享的策略来减少网络参数,这将增加网络的深度,使得运行网络花费大量的时间,从而很难将模型部署到现实生活中。为了解决上述问题,本文设计一种轻量级超分辨率网络,对中间特征的关联性及重要性进行学习,且在重建部分结合高分辨率图像的特征信息。首先,引入层间注意力模块,通过考虑层与层之间的相关性,自适应地分配重要层次特征的权重。其次,使用增强重建模块提取高分辨率图像中更精细的特征信息,以此得到更加清晰的重建图片。通过大量的对比实验表明,本文设计的网络与其他轻量级模型相比,有更小的网络参数量,并且在重建精度和视觉效果上都有一定的提升。 相似文献
2.
Among various carbon materials, diamond stands out due to excellent physical and chemical properties. In this work, we designed Dia@SiO2@Ag composites combining diamond micropowder and Ag nanoparticles by a simple chemical method and obtained stable substrate for surface enhanced Raman scattering (SERS) owing to its high surface-to-volume ratio, low density, as well as close bond between diamond and Ag. As-prepared Dia@SiO2@Ag presented high activity to detect crystal violet and rhodamine 6G molecules, which was demonstrated by significantly enhanced SERS spectra and high enhancement factor values (108-109). Moreover, Dia@SiO2@Ag also showed desired sensitivity, which was investigated by detection limit. Therefore, our study provided more theoretical support and broadened the functional applications of diamond, particularly in Raman detection. 相似文献
3.
A random placement of large-scale sensor network in the outdoor environment often causes low coverage.An area coverage optimization algorithm of mobile sensor network (MSN) based on virtual force perturbation and Cuckoo search (VF-CS) was proposed.Firstly,the virtual force of the sensor nodes within the Thiessen polygon was analyzed based on the partitioning of Voronoi diagram of the monitoring area.Secondly,the force of polygon vertices and neighbor nodes was taken as the perturbation factor for updating the node’s location of the Cuckoo search (CS).Finally,the VF-CS guided the node to move so as to achieve the optimal coverage.The simulation results demonstrate that the proposed algorithm has higher coverage and shorter average moving distance of nodes than the Voronoi diagram based algorithms in literatures. 相似文献
4.
建立并优化一种基于高效薄层色谱和表面增强拉曼联用检测技术的方法,用于快速准确定性定量检测葡萄汁中的苏丹染料掺伪。使用石油醚/丙酮/乙酸(9/1/0.1,体积比)作为流动相在硅胶板上对目标物进行色谱分离,考察纳米银胶体浓度、外加电解质种类、浓度以及入射激光波长等参数对检测信号质量的影响。结果表明,10倍浓缩的纳米银胶体,633nm入射激光,辅以0.5~1.0mol/L NaCl最适合4种目标物的检测。优化检测条件后,检测灵敏度可达0.01~0.05mg/kg;在1~20 mg/kg浓度范围内,检测结果表现出良好的线性关系,R~20.996。不仅如此,对葡萄汁样品的测试中,该方法也表现出良好的准确性(添加回收率72%~104%)和精密度(RSD 4.5%~9.6%),因此特别适于大批量饮料和食品样品中非法色素添加的筛检。 相似文献
5.
Search results of spatio-temporal data are often displayed on a map, but when the number of matching search results is large, it can be time-consuming to individually examine all results, even when using methods such as filtered search to narrow the content focus. This suggests the need to aggregate results via a clustering method. However, standard unsupervised clustering algorithms like -means (i) ignore relevance scores that can help with the extraction of highly relevant clusters, and (ii) do not necessarily optimize search results for purposes of visual presentation. In this article, we address both deficiencies by framing the clustering problem for search-driven user interfaces in a novel optimization framework that (i) aims to maximize the relevance of aggregated content according to cluster-based extensions of standard information retrieval metrics and (ii) defines clusters via constraints that naturally reflect interface-driven desiderata of spatial, temporal, and keyword coherence that do not require complex ad-hoc distance metric specifications as in -means. After comparatively benchmarking algorithmic variants of our proposed approach – RadiCAL – in offline experiments, we undertake a user study with 24 subjects to evaluate whether RadiCAL improves human performance on visual search tasks in comparison to -means clustering and a filtered search baseline. Our results show that (a) our binary partitioning search (BPS) variant of RadiCAL is fast, near-optimal, and extracts higher-relevance clusters than -means, and (b) clusters optimized via RadiCAL result in faster search task completion with higher accuracy while requiring a minimum workload leading to high effectiveness, efficiency, and user satisfaction among alternatives. 相似文献
6.
7.
Chemical looping glycerol reforming for hydrogen production by Ni@ZrO2 nanocomposite oxygen carriers
Bo Jiang Lin Li Zhoufeng Bian Ziwei Li Yang Sun Zhehao Sun Dawei Tang Sibudjing Kawi Binlin Dou Maria A. Goula 《International Journal of Hydrogen Energy》2018,43(29):13200-13211
The research describes the synthesis of nanocomposite Ni@ZrO2 oxygen carriers (OCs) and lanthanide doping effect on maintaining the platelet-structure of the nanocomposite OCs. The prepared OCs were tested in chemical looping reforming of glycerol (CLR) process and sorption enhanced chemical looping reforming of glycerol (SE-CLR) process. A series of characterization techniques including N2 adsorption-desorption, X-ray diffraction (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), high resolution transmission electron microscopy (HRTEM), H2 temperature-programmed reduction (H2-TPR), H2 pulse chemisorption and O2 temperature-programmed desorption (O2-TPD) were used to investigate the physical properties of the fresh and used OCs. The results show that the platelet-stack structure of nanocomposite OCs could significantly improve the metal support interaction (MSI), thus enhancing the sintering resistance. The effect of lanthanide promotion on maintaining this platelet-stack structure increased with the lanthanide radius, namely, La3+ > Ce3+ > Pr3+ > Yb3+. Additionally, the oxygen mobility was also enhanced because of the coordination of oxygen transfer channel size by doping small radius lanthanide ions. The CeNi@ZrO2 showed a moderate ‘dead time’ of 220 s, a high H2 selectivity of 94% and a nearly complete glycerol conversion throughout a 50-cycle CLR test. In a 50-cycle SE-CLR stability test, the CeNi@ZrO2CaO showed high H2 purity of 96.3%, and an average CaCO3 decomposition percentage of 53% without external heating was achieved. 相似文献
8.
文章首先总结了电力企业信息管理系统的现状,提出了多源信息管理系统融合集成的邦联、子集和完全融合3种方式,分析了3种方式的优缺点,以建设企业"互联网搜索"型数字引擎为目标,提出了融合基于本体的图数据库建模,多维关联与路径因果分析,和人机共生互动可视化决策于一体的企业信息管理系统技术发展趋势;在系统分析目前正在快速发展的图数据库技术与传统关系数据库之间的本质区别基础上,总结原创的电力图计算平台技术的特点;在此基础上讨论"电网一张图"在建设能源互联网时空信息管理平台数据关联索引图中的核心作用,提出了支持能源互联网建设的"电网一张图"时空信息管理系统的技术架构与特点,最后总结"电网一张图"时空信息管理系统在提高电网安全运行水平、提升客户服务水平、增强清洁能源消纳水平、改善经营绩效水平、以及为综合能源服务和建设能源生态等提供数据服务方面的广阔应用场景。 相似文献
9.
微地震监测技术通过对非常规储层压裂改造引发的震源点进行成像,实时提供压裂施工过程中产生的裂隙高度、长度、宽度和方位角等信息,为致密储层压裂提供指导,以提高油气采收率。在地面布设站点进行监测时,因微地震信号传播距离较远、近地表吸收衰减严重、地面有源噪声较多,微地震数据具有信号能量弱、噪声干扰强和信噪比低等特点,严重制约微地震事件的定位精度。噪声源多分布于地表,根据有源噪声与由储层向上传播的微地震事件在能量、频率、传播速度和源位置等方面的差异,本文提出微地震有源噪声自动识别与匹配方法。综合长短时窗能量比与微地震量板方法,自动识别有源噪声干扰,并进行噪声源位置和传播速度的三维最优并行搜索;利用同时确定的最优噪声源位置和传播速度对微地震数据进行动校正处理,得到噪声标准道,通过能量自适应匹配处理压制有源噪声。正演模拟数据和实际微地震数据去噪效果证明,本文方法能有效压制有源噪声,显著提高微地震数据品质,为后续微地震事件精确定位奠定了基础。 相似文献
10.
Mohammad Hosein Emami Baghdadi Houman Darvish Hosein Zanbouri Karim Rouhibakhsh 《Petroleum Science and Technology》2018,36(11):787-792
Recently the studies expressed that the noticeable number of oil reservoirs in all over the world are heavy oil and bitumen reservoirs. So the importance of enhancement of oil recovery (EOR) processes for heavy oil and bitumen reservoirs is highlighted. The Dilution of the reservoir fluid by solvents such as tetradecane is one of well-known methods for these types of reservoirs which effects oil recovery by decreasing viscosity. In the present study, Fuzzy c-means (FCM) algorithm was coupled with Adaptive neuro-fuzzy inference system (ANFIS) to predict viscosity of bitumen and tetradecane in terms of temperature, pressure and weight percent of tetradecane. The coefficients of determination for training and testing steps were calculated such as 0.9914 and 0.9613. The comparison of results and experimental data expressed that FCM-ANFIS algorithm has great potential for estimation of viscosity of bitumen and tetradecane. 相似文献