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21.
鉴于高斯混合模型对背景变化快时无法精确检测出目标和目标跟踪的适应性差等瑕疵,提出了基于加权似然跟踪器来改进高斯混合模型实现运动目标跟踪算法。主要引入了自适应高斯混合模型来实时检测运动目标,然后空间加权似然来进行视频中的目标定位,引入加权似然期望值来改进高斯混合模型处理视频中的多尺度、多角度变化的目标跟踪不精准问题。通过VOT 2014 dataset对比实验结果表明提出的基于加权似然跟踪(Weighted Likelihood Tracking,WLT)和改进高斯混合模型(Improved Gaussian Mixture Model,IGMM)的目标跟踪算法较传统高斯混合模型跟踪算法在跟踪的精度有较大提高。在应对多尺度、多角度变化的目标跟踪表现出了较大的优势。  相似文献   
22.
In this paper, we estimate the parameter values of a fractional-order model of supercapacitors involving fractional derivatives of Liouville-Caputo, Caputo-Fabrizio, and Atangana-Baleanu and fractional conformable derivative in the Liouville-Caputo sense. We present the exact solution of the considered model using the properties of the Laplace transform operator together with the convolution theorem. They developed numerical simulations using each one of the fractional derivatives; the results were compared graphically with experimental data obtained from different supercapacitors using standard laboratory equipment. The nonlocal parameters involved in the equivalent electrical circuit for the supercapacitor model are recalculated for each fractional derivative using a particle swarm optimization algorithm for generating optimal solutions.  相似文献   
23.
This study investigates the unsteady electro-osmotic flow (EOF) of a fractional second-grade fluid through a vertical microchannel with convection heat transfer. The fractional Cattaneo heat flux model will be used to modify the heat equation. The solutions for the velocity and the temperature have been derived by employing the Laplace and finite Fourier sine transforms and their numerical inverses. The results show that at the beginning of the time period, the fractional parameter postpones the movement of the fluid. Furthermore, the results show that at the high values of retardation time (non-Newtonian case), the required time for the velocity and the flow rate to reach the steady state increases. Moreover, the heat relaxation time reduces the heat transfer until a critical time, and then the effect reverses.  相似文献   
24.
Robust Parametric Sensitivity Analysis (PSA) is a prerequisite for efficient shape optimisation via parametric modelling. A major challenge PSA has to handle is related to the fact that a parameter can be sensitive in certain local areas of the design space but become insensitive in others. Therefore, setting an applicable space for this analysis becomes a difficult task. In this paper, we introduce the concept of intra-sensitivity to identify parameters whose perturbation has a major impact on the sensitivity index of the remaining parameters. For this purpose, we firstly appeal to Active Subspace Method (ASM) and develop an ASM-based regional sensitivity analysis, which investigates parametric sensitivity in local regions of the design space and aids conducing to parameters’ intra-sensitivity. This regional analysis is applied in conjunction with a Dynamic Propagation Sampling approach, for tackling the computational complexity arising when high-dimensional problems are concerned. Once sensitive and intra-sensitive parameters are identified, then free-form features, correlated to these parameters, are evaluated using a feature saliency map built with the aid of Hausdorff distance. The so resulting methodology has been validated in the area of computer-aided ship design using two parametric modellers: the first one is a Procedural Deformation (PD) modeller which is based on T-splines and involves 24 parameters while the second one is based on Free-Form Deformation (FFD) and involves 104 parameters. The corresponding design spaces have been generated using a parent hull close to the KCS container ship and are analysed against hull’s volume of displacement and total resistance. Finally, the convergence performance of the various components of this approach is compared with state-of-the-art techniques.  相似文献   
25.
While technological transformations have redrawn the boundaries of regional innovation systems, the effect of such transformations on the development of cross-border regional innovation systems (CBRISs) – defined here as the innovation system spanning neighboring territories belonging to different nation-states – has not been well understood. The Hong Kong-Shenzhen region presents a unique opportunity to study the potential of CBRISs, as Hong Kong and Shenzhen are adjacent to each other though there is a border between them and the two cities have their own political and legal systems under the “one country, two systems” arrangement. In this research, we examine the development of the Hong Kong-Shenzhen region by focusing on cognitive proximity, innovation actors, collaboration, and global connectivity through an analysis of patent and publication data for the 2001–2015 period. Our findings point to a good potential given the growing convergence in scientific research among the two cities, steadily increasing collaboration output, and a complementarity among innovation actors. However, compared with other cross-border regions, the technological linkages between Hong Kong and Shenzhen remain limited.  相似文献   
26.
Knowledge distillation has become a key technique for making smart and light-weight networks through model compression and transfer learning. Unlike previous methods that applied knowledge distillation to the classification task, we propose to exploit the decomposition-and-replacement based distillation scheme for depth estimation from a single RGB color image. To do this, Laplacian pyramid-based knowledge distillation is firstly presented in this paper. The key idea of the proposed method is to transfer the rich knowledge of the scene depth, which is well encoded through the teacher network, to the student network in a structured way by decomposing it into the global context and local details. This is fairly desirable for the student network to restore the depth layout more accurately with limited resources. Moreover, we also propose a new guidance concept for knowledge distillation, so-called ReplaceBlock, which replaces blocks randomly selected in the decoded feature of the student network with those of the teacher network. Our ReplaceBlock gives a smoothing effect in learning the feature distribution of the teacher network by considering the spatial contiguity in the feature space. This process is also helpful to clearly restore the depth layout without the significant computational cost. Based on various experimental results on benchmark datasets, the effectiveness of our distillation scheme for monocular depth estimation is demonstrated in details. The code and model are publicly available at : https://github.com/tjqansthd/Lap_Rep_KD_Depth.  相似文献   
27.
本文从传统和地域的角度回顾了木构建筑在瑞士及阿尔卑斯地区的历史发展过程,并论述了其在生产技术方面的进步对设计过程和造型的影响。  相似文献   
28.
通过对南平市文博园博物馆的设计实践,从空间设计、平面布局、细部设计等方面阐述建筑功能、内涵、造型三者之间的关系,论述建筑设计中现代主义与地域文化传承之间的关系。  相似文献   
29.
李正涛 《山西建筑》2005,31(8):14-15
阐述了地域因素是贯穿建筑历史研究的一根线索,揭示出对于建筑地域性的研究,把建筑放在完整的社会、历史、环境背景中,是在动态中研究,指出建筑地域性的研究,对于建筑发展的多元化具有积极的意义。  相似文献   
30.
近年来快速城镇化过程中,西北乡 村建设与地域文化发展出现了种种问题。 在乡村振兴战略的背景下,如何在复杂的城 乡系统中找到合适的切入点打通症结,解决 文化、空间、生态多系统的“乡村病”值得深 思。本文针对乡村发展的现实问题,以当地 普遍建设的生土建筑为切入点,以生态宜居 建设与地域文化传承为目标,提出一系列相 关保护与更新策略,并以定西市通渭县为例 探讨。策略包括在提炼当地传统民居生态特 性的基础上,以工程技术手段优化生土建筑 的材料性能与建筑结构,扩大生态与社会可 持续效益;凝练生土建筑文化特性为设计建 设基础,以技术研究、绿色教育与艺术活动 激活文化内生动力,并完善法规规范支持地 域文化传承。实现将生土建筑发展成果有策 略地整合,为西北乡村振兴实践提供参考。  相似文献   
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