Spatial Perceptual Quality Aware Adaptive Volumetric Video Streaming

Volumetric video offers a highly immersive viewing experience, but poses challenges in ensuring quality of experience (QoE) due to its high bandwidth requirements. In this paper, we explore the effect of viewing distance introduced by six degrees of freedom (6DoF) spatial navigation on user's perceived quality. By considering human visual resolution limitations, we propose a visual acuity model that describes the relationship between the virtual viewing distance and the tolerable boundary point cloud density. The proposed model satisfies spatial visual requirements during 6DoF exploration. Additionally, it dynamically adjusts quality levels to balance perceptual quality and bandwidth consumption. Furthermore, we present a QoE model to represent user's perceived quality at different viewing distances precisely. Extensive experimental results demonstrate that, the proposed scheme can effectively improve the overall average QoE by up to 26% over real networks and user traces, compared to existing baselines.Comment: Accepted byIEEE Globecom 202

Cross-modal and Cross-domain Knowledge Transfer for Label-free 3D Segmentation

Current state-of-the-art point cloud-based perception methods usually rely on large-scale labeled data, which requires expensive manual annotations. A natural option is to explore the unsupervised methodology for 3D perception tasks. However, such methods often face substantial performance-drop difficulties. Fortunately, we found that there exist amounts of image-based datasets and an alternative can be proposed, i.e., transferring the knowledge in the 2D images to 3D point clouds. Specifically, we propose a novel approach for the challenging cross-modal and cross-domain adaptation task by fully exploring the relationship between images and point clouds and designing effective feature alignment strategies. Without any 3D labels, our method achieves state-of-the-art performance for 3D point cloud semantic segmentation on SemanticKITTI by using the knowledge of KITTI360 and GTA5, compared to existing unsupervised and weakly-supervised baselines.Comment: 12 pages,4 figures,accepte

Variation in ovine DGAT1 and its association with carcass muscle traits in Southdown sheep

Diacylglycerol O-acyltransferase 1 (DGAT1) is a microsomal enzyme that plays a key role in the synthesis of triglycerides. Its gene (DGAT1) is regarded as a candidate gene for variation in milk and meat traits in cattle. The objective of this study was to use a PCR single-strand conformation polymorphism approach to explore sequence variation in two regions of ovine DGAT1 and to assess its effect on meat traits in New Zealand Southdown sheep. Three variant nucleotide sequences were identified in each region, with two single nucleotide polymorphisms (SNPs) and one nucleotide deletion being detected in intron 1 and two SNPs being found in exon 17. The effect of the exon 17 variation was not investigated due to one variant being predominant and the other two variants occurring at low frequencies. In intron 1, one variant (B₁) was found to be associated with increase loin meat yield, suggesting that this may have value as a gene marker for improving meat traits

Variation in the Yak calpastatin gene (CAST)

Calpastatin (CAST) is a specific inhibitor of calpain (calcium-dependent cysteine protease). This study investigated the potential for variation in yak (Bos grennies) CAST. PCR-SSCP analysis of exon 6 of yak CAST revealed three unique patterns (named A-C). Sequencing of the amplicons revealed two nucleotide substitutions. One substitution (c.398G/C) would nominally change the amino acid sequence (p.S133T) of yak calpastatin. The variant sequence A which carried c.398C was the most common in the yaks tested (95.1%). This is the first report that found yak CAST is variable, and as in pigs, sheep and cattle, this variation may affect animal production traits

GAMNet: Global attention via multi‐scale context for depth estimation algorithm and application

Abstract Deep neural networks significantly enhance the accuracy of the stereo‐based disparity estimation. Some current methods suffer from inefficient use of the global context information, which will lead to the loss of structural details in ill‐posed areas. To this end, a novel stereo network GAMNet is designed, composed of three core components (GDA, MPF, DCA) for estimating the depth prediction in challenging real‐world environments. First, a lightweight attention module is presented, integrating the global semantic cues for every feature position across the channel and spatial dimensions. Next, the MPF module is constructed to fuse the diverse semantic and contextual information from different levels of the feature pyramid. Finally, cost volume is aggregated with a stacked encoder‐decoder composed of the DCA module and 3D convolutions, filtering the transmission of matching clues and capturing the rich global contexts. Substantial experiments conducted on KITTI 2012, KITTI 2015, SceneFlow, and Middlebury‐v3 datasets manifest that GAMNet surpasses preceding methods with contour‐preserving disparity predictions. In addition, the first 3D scene reconstruction linear evaluation strategy on spatial grasping points for the end‐to‐end stereo networks in an unsupervised mode is proposed, and it is deployed on the designed robot vision‐guided system. In application experiments, the method can produce densely high‐precision 3D reconstructions to implement the grasping task in complex real‐world scenes, and achieve excellent robust performance with competitive inference efficiency

Variation in the ovine hormone-sensitive lipase gene (HSL) and its association with growth and carcass traits in New Zealand Suffolk sheep

The hormone-sensitive lipase (HSL) plays an important role in the regulation of lipolysis in adipose tissues, by catalysing a rate-limiting step in triglyceride hydrolysis. Variation within the human HSL gene (HSL) has been associated with an increased risk of obesity. In this study, variation within three regions (exon 3-4, exon 5-6 and exon 9) of ovine HSL was investigated in 538 Suffolk lambs bred from 13 independent sires using PCR-SSCP. Four sequence variants of intron 5 (designated A-D) and two variants of exon 9 (designated a and b) of ovine HSL were detected. No variation was found in exon 3-4 of the gene. The associations of the variation within ovine HSL with post-weaning growth and carcass traits including eye muscle depth (EMD), eye muscle width (EMW) and fat depth above the eye muscle (FDM) were assessed in 262 of the above 538 lambs using general linear mixed-effects models. In the single variant models, the presence of intron 5 A in a lamb's genotype was associated with reduced EMD (P = 0.036) and EMW (P = 0.018), whereas the presence of intron 5 C was associated with increased EMD (P < 0.001), EMW (P < 0.001) and FDM (P = 0.017). The association of C with increased EMD (P = 0.002) and EMW (P = 0.002) persisted in the multi-variant model. No association between HSL intron 5 variants and post-weaning growth, or between HSL exon 9 variants, post-weaning growth or carcass traits, were found. © 2014 Springer Science+Business Media Dordrecht

Variation in the ovine PRKAG3 gene

The 5'AMP-activated protein kinase (AMPK) is a heterotrimeric enzyme that controls cellular energy homeostasis in response to environmental or nutritional stress. The PRKAG3 gene (PRKAG3) encodes the γ3 subunit of the AMPK. Variation in this gene has been found to be associated with meat quality traits in pigs. In this study, we used polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) to investigate variation in exon 3 and exons 4-6 of ovine PRKAG3. In 160 New Zealand Suffolk sheep, two variant sequences (named a and b) were identified in the exon 3 region of the gene and three variant sequences (named A, B and C) were identified in the exon 4-6 region of the gene, respectively. A total of three nucleotide substitutions were revealed and these were located in intron 4, exon 4 and intron 5, respectively. The nucleotide substitution identified in the exon 4 (g.2656 C > T) could nominally lead to an amino acid substitution of tryptophan to arginine at position 230 (R230W) in ovine PRKAG3. In comparison with the PRKAG3 amino acid sequences in other species, this R230W substitution appeared to occur only in sheep. This is the first report of genetic variation in ovine PRKAG3, and the variation found in this study could be functionally important for AMPK activity, which in turn may affect meat quality traits in sheep

Genetic variation in the ovine uncoupling protein 1 gene: Association with carcass traits in New Zealand (NZ) Romney sheep, but no association with growth traits in either NZ Romney or NZ Suffolk sheep

The uncoupling protein 1 (UCP1) plays an important role in the regulation of lipolysis and thermogenesis in adipose tissues. Genetic variation within three regions (the promoter, intron 2 and exon 5) of the ovine UCP1 gene (UCP1) was investigated using polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) analyses. These revealed three promoter variants (designated A, B and C) and two intron 2 variants (a and b). The association of this genetic variation with variation in lamb carcass traits and postweaning growth was investigated in New Zealand (NZ) Romney and Suffolk sheep. The presence of B in a lamb's genotype was associated with decreased subcutaneous carcass fat depth (V-GR) (p = 0.004) and proportion of total lean meat yield of loin meat (p = 0.005), and an increased proportion of total lean meat yield of hind-leg meat (p = 0.018). In contrast, having two copies of C was associated with increased V-GR (p < 0.001) and proportion of total lean meat yield of shoulder meat (p = 0.009), and a decreased hind-leg yield (p = 0.032). No associations were found with postweaning growth. These results suggest that ovine UCP1 is a potential gene marker for carcass traits