1,147 research outputs found
Acoustic manipulation of sound with soft material-based actuators
No full textThis thesis describes a unique parabolic acoustic manipulator with an inflatable structure, which has high gain and directivity. We created a morphable elastomeric reflecting surface with a diameter of 14 cm (6 in). Applying vacuum deforms the device into a concave structure, which provides directional amplification of incoming acoustic waves. In addition, the author characterized the impedance of the soft material employed in the acoustic reflector, Ecoflex 00-10, in an impedance tube. Ecoflex 00-10 has a measured reflection coefficient of approximately 0.9 at frequencies ranging from 500 Hz to 5000 Hz. This new characterization suggests this class of silicone-based elastomers is capable of advanced morphable devices to manipulate sound. Simulations also demonstrate that the soft reflecting surface is capable of transformation into a set of desired parabolic shapes between an initial planar geometry (neutral position) and a configuration with maximum curvature. With an applied vacuum, the membrane reaches its maximum deformation limited by the aluminum housing. At this stage of actuation, experimental results show the deformed membrane has similar gain and directionality (polar response) as rigid parabolic reflectors. This type of system might find future uses for adjustable parabolic microphones and long-range communication devices.M.S.Includes bibliographical referencesby Yanjun Wan
Distributed video coding for video communication on mobile devices and sensors
No full textIn the context of digital video coding, recent insights have led to a new video coding paradigm called Distributed Video Coding, or DVC, characterized by low-complexity encoding and high-complexity decoding, which is in contrast to traditional video coding schemes. This chapter provides a detailed overview of DVC by explaining the underlying principles and results from information theory and introduces a number of application scenarios. It also discusses the most important practical architectures that are currently available. One of these architectures is analyzed step-by-step to provide further details of the functional building blocks, including an analysis of the coding performance compared to traditional coding schemes. Next to this, it is demonstrated that the computational complexity in a video coding scheme can be shifted dynamically from the encoder to the decoder and vice versa by combining conventional and distributed video coding techniques. Lastly, this chapter discusses some currently important research topics of which it is expected that they can further enhance the performance of DVC, i.e., side information generation, virtual channel noise estimation, and new coding modes
Fast mode decision in H.264/AVC
No full textThe latest video coding standard (Wiegand, 2003), H.264/AVC, uses variable block sizes ranging from 16x16 to 4x4 to perform motion estimation in inter-frame coding and a rich set of prediction patterns for intra-frame coding. Then a robust RDO (Rate Distortion Optimization) technique is employed to select the best coding mode and reference frame for each macroblock. As a result, H.264/AVC exhibits high coding efficiency compared to older video coding standards [2, 3] and shows significant future promise in the fields of video broadcasting and communication. However, high coding efficiency also carries high computational complexity. Fast mode decision is one of the key techniques to significantly reducing computational complexity for a similar RD (Rate Distortion) performance. This chapter provides an up-to-date critical survey of fast mode decision techniques for the H.264/AVC standard. The motivation for this chapter is twofold: Firstly to provide an up-to-data review of the existing techniques and secondly to offer some insights into the studies of fast mode decision techniques
Nitrate and phosphate supplementation to increase toxin production by the marine dinoflagellate Alexandrium tamarense
No full textAlexandrium tamarense toxins have great value in biotechnology research as well as important in connection with shellfish poisoning. The influence of nitrate or nitrate and phosphate supplementation on cell biomass and toxin content were investigated in batch cultures. When cultures at low nitrate (88.2 mu M NaNO3) Were supplemented with 793.8 mu M NaNO3 at day 10 the cell density and cellular toxin contents were increased by 6-29% and 20-76%, respectively, compared with controls, and maximal values were 43,600 cells/ml (day 38) and 0.91 pg/cell (day 31). Supplementation with nitrate at day 14 or with nitrate and phosphate at day 10/14 to the cultures did not increase the cell density compared with the non-supplemented middle nitrate or high phosphate (108 mu M NaH2PO4) cultures, respectively, but increased the cellular toxin contents by an average of 52%. The results showed that supplementation with nitrate or with nitrate and phosphate at different growth phases of the cultures increased toxin yield by an average of 46%. Supplementation with nitrate at selected times to maintain continuous low level of nitrate might contribute to the effective increase of toxin yield of A. tamarense. (c) 2005 Elsevier Ltd. All rights reserved.Alexandrium tamarense toxins have great value in biotechnology research as well as important in connection with shellfish poisoning. The influence of nitrate or nitrate and phosphate supplementation on cell biomass and toxin content were investigated in batch cultures. When cultures at low nitrate (88.2 mu M NaNO3) Were supplemented with 793.8 mu M NaNO3 at day 10 the cell density and cellular toxin contents were increased by 6-29% and 20-76%, respectively, compared with controls, and maximal values were 43,600 cells/ml (day 38) and 0.91 pg/cell (day 31). Supplementation with nitrate at day 14 or with nitrate and phosphate at day 10/14 to the cultures did not increase the cell density compared with the non-supplemented middle nitrate or high phosphate (108 mu M NaH2PO4) cultures, respectively, but increased the cellular toxin contents by an average of 52%. The results showed that supplementation with nitrate or with nitrate and phosphate at different growth phases of the cultures increased toxin yield by an average of 46%. Supplementation with nitrate at selected times to maintain continuous low level of nitrate might contribute to the effective increase of toxin yield of A. tamarense. (c) 2005 Elsevier Ltd. All rights reserved
A Study of the Resistance of Hu Sheep Lambs to Escherichia coli F17 Based on Whole Genome Sequencing
No full textThis study aims to analyze the whole genome sequencing of E. coli F17 in antagonistic and susceptible Hu sheep lambs. The objective is to investigate the critical mutation loci in sheep and understand the genetic mechanism of sheep resistance to E. coli F17 at the genome level. Antagonist and susceptible venous blood samples were collected from Hu sheep lambs for whole genome sequencing and whole genome association analysis. A total of 466 genes with significant SNPs (p < 1.0 × 10−3) were found. GO and KEGG enrichment analysis and protein interaction network analysis were performed on these genes, and preliminary investigations showed that SNPs on CTNNB1, CDH8, APOD, HCLS1, Tet2, MTSS1 and YAP1 genes may be associated with the antagonism and susceptibility of Hu sheep lambs to E. coli F17. There are still some shortcomings that have not been explored via in vivo and in vitro functional experiments of the candidate genes, which will be our next research work. This study provides genetic loci and candidate genes for resistance of Hu sheep lambs to E. coli F17 infection, and provides a genetic basis for breeding disease-resistant sheep
Unexpected enrichment of thallium and its geochemical behaviors in soils impacted by historically industrial activities using lead‐zinc carbonate minerals
No full text: Thallium is a trace metal with severe toxicity. Contamination of thallium (Tl) generated by steel and non-ferrous metals industry is gaining growing concern worldwide. However, little is known on Tl contamination owing to industrial activities using carbonate minerals. This study revealed abundant geochemical mobile/bioavailable Tl (> 65.7%, in average; mostly in oxidizable fraction) in soils from a carbonate-hosted PbZn ore utilizing area in China for the first time. Unexpected Tl enrichment was observed in soil accompanying with 3655, 7820, 100.1, 27.3 and 29.9 mg/kg (in average) of Pb, Zn, As, Cd and Sb, respectively. Characterization using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis further confirmed that historical industrial activities impose anthropogenic catastrophic effects on the local agricultural soil system. The ecological and health risk assessment of heavy metal(loid)s in soils proclaimed serious potential non-carcinogenic risks of Pb and V to adults, and Pb, Tl and As to children. Sequential extraction analysis showed that Tl, as well as Pb, Zn, Mn, Co, and Cd, mainly existed in the mobile fractions (exchangeable/acid-extractable, reducible and oxidizable), indicating an ecological risk of biological accumulation of multiple metal(loid)s in this area. These findings provide a theoretical basis for taking appropriate remediation measures in order to ensure safety of soils in such industrial areas likewise
AudioEar: Single-View Ear Reconstruction for Personalized Spatial Audio
No full textAbstract
We introduce AudioEar3D, a high-quality 3D ear dataset consisting of 112 point cloud ear scans with RGB images, to benchmark the ear reconstruction task. We further collect a 2D ear dataset composed of 2,000 images, each one with manual annotation of occlusion and 55 landmarks, named AudioEar2D. To our knowledge, both datasets have the largest scale and best quality of their kinds for public use.
Usage
The code is publicly available at https://github.com/seanywang0408/AudioEar.
The file organization of AudioEar3D is as following:
AudioEar3D
├── 001
# left ear data
├── left.jpg # processed RGB image of left ear
├── left.ply # processed point cloud of left ear in canonical pose (frontal view is negative-X and upper view is positive-Z)
├── left.json # 56 landmark annotations of image
├── mask_left.jpg # mask generated by the outer landmarks
├── masked_left.jpg # exclude background in left.jpg using mask_left.jpg
├── masked_left.png # exclude background in left.jpg using mask_left.jpg, but with four channels of RGB-A
# right ear data
├── right.jpg
...
├── masked_right.png
├── 002
...
├── 056
The file organization of AudioEar2D is as following:
AudioEar2D
├── 00000.png # processed ear image
├── 00000.json # landmark annotations
...
├── 69985.png # the index is aligned with the data source FFHQ.
├── 69985.json
Citation
If you find this project useful, currently please cite the paper as:
Xiaoyang Huang, Yanjun Wang, Yang Liu, Bingbing Ni, Wenjun Zhang, Jinxian Liu, Teng Li. "AudioEar: Single-View Ear Reconstruction for Personalized Spatial Audio". arXiv preprint arXiv:2301.12613, 2023.
or using bibtex:
@article{huang2023audioear,
title={AudioEar: Single-View Ear Reconstruction for Personalized Spatial Audio},
author={Huang, Xiaoyang and Wang, Yanjun and Liu, Yang and Ni, Bingbing and Zhang Wenjun and Liu Jinxian and Li, Teng},
journal={arXiv preprint arXiv:2301.12613},
year={2023}
}
License
The dataset is licensed under Creative Commons Attribution 4.0 International (CC BY 4.0).
The code is under Apache-2.0 License.
Mirror Link
We recommend users to download the data from Zenodo official link. However, if you find any downloading problem, you can also use this mirror link from Google Drive.
Changelog
v1.0: Initial repository of AudioEar3D and AudioEar2D
Imaging the spread of reversible brain inactivations using fluorescent muscimol
No full textAuthor manuscript. Published in final edited form as:
J Neurosci Methods. 2008 June 15; 171(1): 30–38
Precious-Metal-Free CO 2 Photoreduction Boosted by Dynamic Coordinative Interaction between Pyridine-Tethered Cu(I) Sensitizers and a Co(II) Catalyst
No full textPopulus euphratica XTH overexpression enhances salinity tolerance by the development of leaf succulence in transgenic tobacco plants
No full textPopulus euphratica is a salt-tolerant tree species that develops leaf succulence after a prolonged period of salinity stress. In the present study, a putative xyloglucan endotransglucosylase/hydrolase gene (PeXTH) from P. euphratica was isolated and transferred to tobacco plants. PeXTH localized exclusively to the endoplasmic reticulum and cell wall. Plants overexpressing PeXTH were more salt tolerant than wild-type tobacco with respect to root and leaf growth, and survival. The increased capacity for salt tolerance was due mainly to the anatomical and physiological alterations caused by PeXTH overexpression. Compared with the wild type, PeXTH-transgenic plants contained 36% higher water content per unit area and 39% higher ratio of fresh weight to dry weight, a hallmark of leaf succulence. However, the increased water storage in the leaves in PeXTH-transgenic plants was not accompanied by greater leaf thickness but was due to highly packed palisade parenchyma cells and fewer intercellular air spaces between mesophyll cells. In addition to the salt dilution effect in response to NaCl, these anatomical changes increased leaf water-retaining capacity, which lowered the increase of salt concentration in the succulent tissues and mesophyll cells. Moreover, the increased number of mesophyll cells reduced the intercellular air space, which improved carbon economy and resulted in a 47–78% greater net photosynthesis under control and salt treatments (100–150mM NaCl). Taken together, the results indicate that PeXTH overexpression enhanced salt tolerance by the development of succulent leaves in tobacco plants without swelling
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