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1.
Interface shear strength of geosynthetic clay liners (GCL) with the sand particles is predominantly influenced by the surface characteristics of the GCL, size and shape of the sand particles and their interaction mechanisms. This study brings out the quantitative effects of particle shape on the interaction mechanisms and shear strength of GCL-sand interfaces. Interface direct shear tests are conducted on GCL in contact with a natural sand and a manufactured sand of identical gradation, eliminating the particle size effects. Results showed that manufactured sand provides effective particle-fiber interlocking compared to river sand, due to the favorable shape of its grains. Further, the role of particle shape on the hydration of GCL is investigated through interface shear tests on GCL-sand interfaces at different water contents. Bentonite hydration is found to be less in tests with manufactured sand, leading to better interface shear strength. Grain shape parameters of sands, surface changes related to hydration and particle entrapment in GCL are quantified through image analysis on sands and tested GCL surfaces. It is observed that the manufactured sand provides higher interface shear strength and causes lesser hydration related damages to GCL, owing to its angular particles and low permeability.  相似文献   
2.
The muon radiography imaging technique for high-atomic-number objects(Z) and large-volume objects via muon transmission imaging and muon multiple scattering imaging remains a popular topic in the field of radiation detection imaging. However, few imaging studies have been reported on low and medium Z objects at the centimeter scale. This paper presents an imaging system that consists of three layers of a position-sensitive detector and four plastic scintillation detectors. It acquires data by co...  相似文献   
3.
The main aim of this work is to improve the security of data hiding for secret image sharing. The privacy and security of digital information have become a primary concern nowadays due to the enormous usage of digital technology. The security and the privacy of users’ images are ensured through reversible data hiding techniques. The efficiency of the existing data hiding techniques did not provide optimum performance with multiple end nodes. These issues are solved by using Separable Data Hiding and Adaptive Particle Swarm Optimization (SDHAPSO) algorithm to attain optimal performance. Image encryption, data embedding, data extraction/image recovery are the main phases of the proposed approach. DFT is generally used to extract the transform coefficient matrix from the original image. DFT coefficients are in float format, which assists in transforming the image to integral format using the round function. After obtaining the encrypted image by data-hider, additional data embedding is formulated into high-frequency coefficients. The proposed SDHAPSO is mainly utilized for performance improvement through optimal pixel location selection within the image for secret bits concealment. In addition, the secret data embedding capacity enhancement is focused on image visual quality maintenance. Hence, it is observed from the simulation results that the proposed SDHAPSO technique offers high-level security outcomes with respect to higher PSNR, security level, lesser MSE and higher correlation than existing techniques. Hence, enhanced sensitive information protection is attained, which improves the overall system performance.  相似文献   
4.
在神威高性能多核服务器上,自动并行化编译系统为识别和申明程序中的并行性,产生的OpenMP程序没有经过充分的优化,其采用简单的fork-join模型,存在大量的并行循环嵌套,导致运行效率低。为提升自动并行化编译系统产生的OpenMP程序的运行效率,提出一种并行域重构优化技术。并行域重构技术通过合并程序中的并行域和扩展嵌套循环中的并行域范围,减少OpenMP程序的并行域数目,降低线程组频繁创建和合并等控制开销,将简单fork-join模型的OpenMP程序转换为性能更为高效的单程序多数据模型的OpenMP程序。实验结果表明,在新一代神威高性能多核服务器SW1621平台上,并行域重构技术在NPB3.3-OMP测试集和SPEC OMP2012测试集上的运行效率分别提高了10.77%和7.94%的,可有效提升自动并行化编译系统OpenMP程序的执行效率。  相似文献   
5.
基于机器视觉的列车部件故障诊断方法提高了人工巡检的速度和准确率,是近年来机器视觉技术的研究热点之一。通过对机器视觉技术在列车故障诊断方面的研究成果的回顾,对其中的图像配准和故障诊断等关键技术进行综述,总结相关原理、优缺点、国内外发展现状。3D技术的发展为列车故障诊断提供了新的研究方向。对3D检测技术的原理及其在列车部件故障诊断方面的应用进行详细介绍。对目前列车部件故障诊断研究中存在的问题和未来发展趋势进行总结和展望。  相似文献   
6.
为了达到良好的图像去雾效果,提出一种高斯自适应多尺度加权滤波去雾算法。通过多尺度最小值加权滤波得到暗通道图像,建立最小通道与高斯函数的关系,线性约束后并经过自适应参数对像素灰度值的调整得到粗级透射率,紧接着对得到的粗级透射率图像进行多尺度加权引导滤波得到优化透射率,结合加权大气光强并依据大气散射模型对图像进行去雾复原处理。实验结果表明,该方法有效地将单幅有雾图像进行了处理,与其他经典算法相比较得到的图像细节显示效果好,很好地恢复了场景的对比度,增加了图像的可见度,具备一定的优异性。  相似文献   
7.
为准确有效识别出农作物病虫害类别及位置,构建一款农作物病虫害图像识别App系统,为广大农户、研究人员及管理者提供智能信息服务。该系统基于Android平台开发,在所收集的大量病虫害数据集上,开展了Darknet、YOLO等深度网络模型训练和测试,并使用批量正则化、维度聚类和课程设计学习等技术优化模型,实现了181种作物病虫害图像的在线识别检测,为复杂环节下农作物病害及虫害在线识别、监管防控、综合治理等提供技术依据。  相似文献   
8.
介绍支持Scratch人工智能插件的可编程机器人,包括机器人和配套无线配置小程序的实现架构及使用流程;阐述造型与背景、图像分类等典型插件和关键积木;通过制作一个鲜花识别机器人,阐述人工智能的基本思想和过程。  相似文献   
9.
Image velocimetry for open channel is safe, efficient and environmentally friendly and large-scale particle image velocimetry (LSPIV) is one of the most adopted methods. Furthermore, robust LSPIV algorithms strongly rely on the error vector filtering strategy. However, previous works mainly conduct filtering by median filtering, main orientation filtering and maximum filtering, and these strategies are not stable enough due to the lack of taking both the visibility and stability of tracer particles into consideration. Meanwhile, statistical property like SNR (Signal-to-Noise Ratio) and peak cross-correlation are unable to estimate the tracer visibility. In order to improve the accuracy, we propose a robust and effective filtering strategy called PPSR (Peak-Peak-Sidelobe-Ratio) from the image matching perspective to ensure the visibility and stability of tracers. We conduct a serial of experiments on the public dataset Brenta and Tiber to prove the effectiveness of the proposed algorithm.  相似文献   
10.
Multi-channel and single-channel image denoising are on two important development fronts. Integrating multi-channel and single-channel image denoisers for further improvement is a valuable research direction. A natural assumption is that using more useful information is helpful to the output results. In this paper, a novel multi-channel and single-channel fusion paradigm (MSF) is proposed. The proposed MSF works by fusing the estimates of a multi-channel image denoiser and a single-channel image denoiser. The performance of recent multi-channel image denoising methods involved in the proposed MSF can be further improved at low additional time-consuming cost. Specifically, the validity principle of the proposed MSF is that the fused single-channel image denoiser can produce auxiliary estimate for the involved multi-channel image denoiser in a designed underdetermined transform domain. Based on the underdetermined transformation, we create a corresponding orthogonal transformation for fusion and better restore the multi-channel images. The quantitative and visual comparison results demonstrate that the proposed MSF can be effectively applied to several state-of-the-art multi-channel image denoising methods.  相似文献   
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