176 research outputs found
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A Tale of Two Villages: Debordering and Rebordering in the Bordered Community Scenic Area
Border is part of the entrenched history and reality of tourist mobility. This study takes the concept of border as the theorical basis to analyze how local borders are produced, developed and transformed in tourism communities. Taking China’s Hongcun Village, a bordered UNESCO World Cultural Heritage Site, and its neighboring community Jicun as the study cases, the authors conducted interviews and observation to explore how local borders are developed. The results show that local borders can be understood from five perspectives in Hongcun Scenic Area: administrative, physical, social-economic, functional and psychological. They are not fixed but interacting with each other and constantly changing. This paper contributes to the literature as it reveals that local borders are always driven by external forces and actors, strongly supported by the market economy. And it conceptualizes borders as processes including bordering, debordering and rebordering, which provides a dynamic perspective to understand tourism impacts
R2P: A Deep Learning Model from mmWave Radar to Point Cloud
Recent research has shown the effectiveness of mmWave radar sensing for
object detection in low visibility environments, which makes it an ideal
technique in autonomous navigation systems. In this paper, we introduce Radar
to Point Cloud (R2P), a deep learning model that generates smooth, dense, and
highly accurate point cloud representation of a 3D object with fine geometry
details, based on rough and sparse point clouds with incorrect points obtained
from mmWave radar. These input point clouds are converted from the 2D depth
images that are generated from raw mmWave radar sensor data, characterized by
inconsistency, and orientation and shape errors. R2P utilizes an architecture
of two sequential deep learning encoder-decoder blocks to extract the essential
features of those radar-based input point clouds of an object when observed
from multiple viewpoints, and to ensure the internal consistency of a generated
output point cloud and its accurate and detailed shape reconstruction of the
original object. We implement R2P to replace Stage 2 of our recently proposed
3DRIMR (3D Reconstruction and Imaging via mmWave Radar) system. Our experiments
demonstrate the significant performance improvement of R2P over the popular
existing methods such as PointNet, PCN, and the original 3DRIMR design.Comment: arXiv admin note: text overlap with arXiv:2109.0918
3D Reconstruction of Multiple Objects by mmWave Radar on UAV
In this paper, we explore the feasibility of utilizing a mmWave radar sensor
installed on a UAV to reconstruct the 3D shapes of multiple objects in a space.
The UAV hovers at various locations in the space, and its onboard radar senor
collects raw radar data via scanning the space with Synthetic Aperture Radar
(SAR) operation. The radar data is sent to a deep neural network model, which
outputs the point cloud reconstruction of the multiple objects in the space. We
evaluate two different models. Model 1 is our recently proposed 3DRIMR/R2P
model, and Model 2 is formed by adding a segmentation stage in the processing
pipeline of Model 1. Our experiments have demonstrated that both models are
promising in solving the multiple object reconstruction problem. We also show
that Model 2, despite producing denser and smoother point clouds, can lead to
higher reconstruction loss or even loss of objects. In addition, we find that
both models are robust to the highly noisy radar data obtained by unstable SAR
operation due to the instability or vibration of a small UAV hovering at its
intended scanning point. Our exploratory study has shown a promising direction
of applying mmWave radar sensing in 3D object reconstruction
VGDiffZero: Text-to-image Diffusion Models Can Be Zero-shot Visual Grounders
Large-scale text-to-image diffusion models have shown impressive capabilities
across various generative tasks, enabled by strong vision-language alignment
obtained through pre-training. However, most vision-language discriminative
tasks require extensive fine-tuning on carefully-labeled datasets to acquire
such alignment, with great cost in time and computing resources. In this work,
we explore directly applying a pre-trained generative diffusion model to the
challenging discriminative task of visual grounding without any fine-tuning and
additional training dataset. Specifically, we propose VGDiffZero, a simple yet
effective zero-shot visual grounding framework based on text-to-image diffusion
models. We also design a comprehensive region-scoring method considering both
global and local contexts of each isolated proposal. Extensive experiments on
RefCOCO, RefCOCO+, and RefCOCOg show that VGDiffZero achieves strong
performance on zero-shot visual grounding
Cell-Free Seminal mRNA and MicroRNA Exist in Different Forms
BACKGROUND: The great interest in cell-free mRNA, microRNA (miRNA) as molecular biomarkers for clinical applications, and as 'signaling' molecules for intercellular communication highlights the need to reveal their physical nature. Here this issue was explored in human cell-free seminal mRNA (cfs-mRNA) and miRNA (cfs-miRNA). METHODOLOGY/PRINCIPAL FINDINGS: Selected male reproductive organ-specific mRNAs, miRNAs, and piRNAs were quantified by quantitative real-time PCR in all experiments. While the stability of cfs-miRNA assessed by time-course analysis (up to 24 h at room temperature) was similar with cfs-mRNA, the reductive changes between cfs-miRNA and cfs-mRNA after filtration and Triton X-100 treatment on seminal plasma were very different, implying their different physical nature. Seminal microvesicles (SMVs) were then recovered and proportions of cfs-mRNA and cfs-miRNA within SMVs were quantified. The amounts of SMVs- sequestered cfs-mRNAs almost were the same as total cfs-mRNA, and were highly variable depending on the different sizes of SMVs. But most of cfs-miRNA was independent of SMVs and existed in the supernatant. The possible form of cfs-miRNA in the supernatant was further explored by filtration and protease K digestion. It passed through the 0.10-µm pore, but was degraded dramatically after intense protease K digestion. CONCLUSIONS/SIGNIFICANCE: The predominant cfs-mRNA is contained in SMVs, while most cfs-miRNA is bound with protein complexes. Our data explained the stability of extracellular RNAs in human semen, and shed light on their origins and potential functions in male reproduction, and strategy of developing them as biomarkers of male reproductive system
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