349 research outputs found

    Learning Clothing and Pose Invariant 3D Shape Representation for Long-Term Person Re-Identification

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    Long-Term Person Re-Identification (LT-ReID) has become increasingly crucial in computer vision and biometrics. In this work, we aim to extend LT-ReID beyond pedestrian recognition to include a wider range of real-world human activities while still accounting for cloth-changing scenarios over large time gaps. This setting poses additional challenges due to the geometric misalignment and appearance ambiguity caused by the diversity of human pose and clothing. To address these challenges, we propose a new approach 3DInvarReID for (i) disentangling identity from non-identity components (pose, clothing shape, and texture) of 3D clothed humans, and (ii) reconstructing accurate 3D clothed body shapes and learning discriminative features of naked body shapes for person ReID in a joint manner. To better evaluate our study of LT-ReID, we collect a real-world dataset called CCDA, which contains a wide variety of human activities and clothing changes. Experimentally, we show the superior performance of our approach for person ReID.Comment: 10 pages, 7 figures, accepted by ICCV 202

    Using GPUs to Compute Large Out-of-card FFTs

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    ABSTRACT The optimization of Fast Fourier Transfer (FFT) problems that can fit into GPU memory has been studied extensively. Such on-card FFT libraries like CUFFT can generally achieve much better performance than their counterparts on a CPU, as the data transfer between CPU and GPU is usually not counted in their performance. This high performance, however, is limited by the GPU memory size. When the FFT problem size increases, the data transfer between system and GPU memory can comprise a substantial part of the overall execution time. Therefore, optimizations for FFT problems that outgrow the GPU memory can not bypass the tuning of data transfer between CPU and GPU. However, no prior study has attacked this problem. This paper is the first effort of using GPUs to efficiently compute large FFTs in the CPU memory of a single compute node. In this paper, the performance of the PCI bus during the transfer of a batch of FFT subarrays is studied and a blocked buffer algorithm is proposed to improve the effective bandwidth. More importantly, several FFT decomposition algorithms are proposed so as to increase the data locality, further improve the PCI bus efficiency and balance computation between kernels. By integrating the above two methods, we demonstrate an out-of-card FFT optimization strategy and develop an FFT library that efficiently computes large 1D, 2D and 3D FFTs that can not fit into the GPU's memory. On three of the latest GPUs, our large FFT library achieves much better double precision performance than two of the most efficient CPU based libraries, FFTW and Intel MKL. On average, our large FFTs on a single GeForce GTX480 are 46% faster than FFTW and 57% faster than MKL with multiple threads running on a four-core Intel i7 CPU. The speedup on a Tesla C2070 is 1.93× and 2.11× over FFTW and MKL. A peak performance of 21GFLOPS is achieved for a 2D FFT of size 2048 × 65536 on C2070 with double precision

    Vegetation restoration in Northern China: A contrasted picture

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    China started a long- term effort to mitigate desertification and ensure the sustainability of its environment by implementing multiple large- scale national ecological restoration projects since 1978, but their success has been highly debated for a long time. Here, we estimated the change of vegetation fraction cover (VFC) in the Three- North Shelterbelt Programme (TNSP) region over the past three decades on the basis of the Normalized Difference Vegetation Index dataset from the Global Inventory Monitoring and Modeling System. We evaluate the national strategy of vegetation restoration in North China by comparing rainfall patterns, vegetation change, and national ecological restoration programs on the basis of the Global Meteorological Forcing Dataset and the China Forestry Statistical Yearbooks. We find that the western, central, and eastern parts of the TNSP region exhibited a distinct increase in vegetation coverage. The western region had the highest increase of annual precipitation, but this did not result in the highest VFC increase. We infer that ecological restoration activities are the factor leading to the observed increase in VFC in the eastern and central region compared with the western region. The low survival rate of planted trees in the forest of the TNSP region indicates that it is necessary to improve the mode of vegetation restoration to obtain optimal returns and avoid excessive investment. The success of new strategies, for example, natural restoration and quasinatural afforestation are promising as an alternative method. China’s experiences in reforestation will be very beneficial for other countries to promote land degradation mitigation and vegetation improvement in the arid and semiarid areas.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154888/1/ldr3314_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154888/2/ldr3314.pd

    Large-scale analyses of heat shock transcription factors and database construction based on whole-genome genes in horticultural and representative plants

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    Heat shock transcription factor (Hsf) plays a critical role in regulating heat resistance. Here, 2950 Hsf family genes were identified from 111 horticultural and representative plants. More Hsf genes were detected in higher plants than in lower plants. Based on all Hsf genes, we constructed a phylogenetic tree, which indicated that Hsf genes of each branch evolved independently after species differentiation. Furthermore, we uncovered the evolutionary trajectories of Hsf genes by motif analysis. There were only six motifs (M1–M6) in lower plants, and then four novel motifs (M7–M10) appeared in higher plants. However, the motifs of some Hsf genes were lost in higher plants, indicating that Hsf genes have undergone sequence variation during their evolution. The number of Hsf genes lost was greater than the number of genes that were duplicated after whole-genome duplication in higher plants. The heat response network was constructed using 24 Hsf genes and 2421 downstream and 222 upstream genes of Arabidopsis. Further enrichment analysis revealed that Hsf genes and other transcription factors interacted with each other in the response to heat stress. Global expression maps were illustrated for Hsf genes under various abiotic and biotic stresses and several developmental stages in Arabidopsis. Syntenic and phylogenetic analyses were conducted using Hsf genes of Arabidopsis and the pan-genome of 18 Brassica rapa accessions. We also performed expression pattern analysis of Hsf and six Hsp family genes using expression values from different tissues and heat treatments in B. rapa. The interaction network between the Hsf and Hsp gene families was constructed in B. rapa, and several core genes were detected in the network. Finally, we constructed an Hsf database (http://hsfdb.bio2db.com) for researchers to retrieve Hsf gene family information. Therefore, our study will provide rich resources for the study of the evolution and function of Hsf genes

    Large-scale analyses of heat shock transcription factors and database construction based on whole-genome genes in horticultural and representative plants

    Get PDF
    Heat shock transcription factor (Hsf) plays a critical role in regulating heat resistance. Here, 2950 Hsf family genes were identified from 111 horticultural and representative plants. More Hsf genes were detected in higher plants than in lower plants. Based on all Hsf genes, we constructed a phylogenetic tree, which indicated that Hsf genes of each branch evolved independently after species differentiation. Furthermore, we uncovered the evolutionary trajectories of Hsf genes by motif analysis. There were only six motifs (M1–M6) in lower plants, and then four novel motifs (M7–M10) appeared in higher plants. However, the motifs of some Hsf genes were lost in higher plants, indicating that Hsf genes have undergone sequence variation during their evolution. The number of Hsf genes lost was greater than the number of genes that were duplicated after whole-genome duplication in higher plants. The heat response network was constructed using 24 Hsf genes and 2421 downstream and 222 upstream genes of Arabidopsis. Further enrichment analysis revealed that Hsf genes and other transcription factors interacted with each other in the response to heat stress. Global expression maps were illustrated for Hsf genes under various abiotic and biotic stresses and several developmental stages in Arabidopsis. Syntenic and phylogenetic analyses were conducted using Hsf genes of Arabidopsis and the pan-genome of 18 Brassica rapa accessions. We also performed expression pattern analysis of Hsf and six Hsp family genes using expression values from different tissues and heat treatments in B. rapa. The interaction network between the Hsf and Hsp gene families was constructed in B. rapa, and several core genes were detected in the network. Finally, we constructed an Hsf database (http://hsfdb.bio2db.com) for researchers to retrieve Hsf gene family information. Therefore, our study will provide rich resources for the study of the evolution and function of Hsf genes

    Decreasing Coalbed Methane Formation Damage Using Microfoamed Drilling Fluid Stabilized by Silica Nanoparticles

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    Coalbed methane (CBM) reservoirs in China are featured in remarkable nanosized pores below 200 nm, acknowledged natural cleats, and tectonic fractures. This paper discussed the possibility that a clay free microfoamed drilling fluid could be stabilized by silica nanoparticles (CFMDF-NP) so as to avoid formation damage of CBM drilling. In accordance with the experimental results of foaming capacity and foam stability test, basic drilling fluid performance appraisal, micromorphology observation, swelling test, and gas permeability test, the mechanism of the CFMDF-NP was discussed in this paper. The results indicated that, with 10–20 nm nano-SiO2, the foaming volume of traditional foamed drilling fluid could be improved by up to 50% and an increased half-life period by up to 200%. Chemically treated nano-SiO2 dispersions functioned as a foam stabilizer and a foaming agent as well. The CFMDF-NP had controllable density (0.7~1 g/cm3) and excellent rheological and sealing properties, which could satisfy the drilling requirements of the low pressure coal seams. With 5–8 mm slicing on the contaminated side of coal cores, the contaminated zone could be removed and the recovery rate of gas permeability could reach up to 70%. The CFMDF-NP laid good technical foundation to decrease formation damage of CBM reservoir
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