875 research outputs found
Pattern Division Multiple Access with Large-scale Antenna Array
In this paper, pattern division multiple access with large-scale antenna
array (LSA-PDMA) is proposed as a novel non-orthogonal multiple access (NOMA)
scheme. In the proposed scheme, pattern is designed in both beam domain and
power domain in a joint manner. At the transmitter, pattern mapping utilizes
power allocation to improve the system sum rate and beam allocation to enhance
the access connectivity and realize the integration of LSA into multiple access
spontaneously. At the receiver, hybrid detection of spatial filter (SF) and
successive interference cancellation (SIC) is employed to separate the
superposed multiple-domain signals. Furthermore, we formulate the sum rate
maximization problem to obtain the optimal pattern mapping policy, and the
optimization problem is proved to be convex through proper mathematical
manipulations. Simulation results show that the proposed LSA-PDMA scheme
achieves significant performance gain on system sum rate compared to both the
orthogonal multiple access scheme and the power-domain NOMA scheme.Comment: 6 pages, 5 figures, this paper has been accepted by IEEE VTC
2017-Sprin
Biochemistry nanosensor based on hybrid metallic nanostructure array
A biochemistry nanosensor based on hybrid metallic nanostructure array was put forward in this paper. The hybrid metallic nanostructure array consists of two types Ag nanostuctures, spherical and pyramidal structures with the same period. A biochemistry sensor experiment is demonstrated by detecting the transmittance spectra of hybrid metallic nanostructure using Sciencetech spectrophotometer. The wave peaks of transmittance spectra have shifts when the metallic periods and the refractive index of Ag nanostuctures are different
The Electronics and Data Acquisition System for the PandaX-I Dark Matter Experiment
We describe the electronics and data acquisition system used in the first
phase of the PandaX experiment -- a 120 kg dual-phase liquid xenon dark matter
direct detection experiment in the China Jin-Ping Underground Laboratory. This
system utilized 180 channels of commercial flash ADC waveform digitizers. This
system achieved low trigger threshold (1 keV electron-equivalent energy) and
low deadtime data acquistion during the entire experimental run.Comment: 12 pages, 6 figures, version as accepted by JINS
Isolation and characterisation of acid soluble collagens and pepsin soluble collagens from Eel (Anguilla japonica Temminck et Schlegel) skin and bone
© 2025 by the authors. Licensee MDPI, Basel, Switzerland.Eel (Anguilla japonica) is an important and valuable food fish in East Asia and its by-products have been reported to include bioactive and profitable components. This study aimed to extract, characterise, and compare the structure and properties of acid-soluble collagens (ASCs) and pepsin-soluble collagens (PSCs) from the skin and bone of eel (Anguilla japonica), providing insights into their composition, structure, and properties for various applications. The yields of ASC-S (from skin), PSC-S (from skin), ASC-B (from bone), and PSC-B (from bone) were 12.16%, 15.54%, 0.79%, and 1.34% on a dry weight basis, respectively. Glycine, the dominant amino acid, accounted for 16.66% to 22.67% of total amino acids in all samples. SDS-PAGE and FTIR analyses showed the typical triple-helical structure of type I collagen with slight variations in molecular order in extract and intermolecular cross-linking between skin and bone collagens. The denaturation temperature (Tmax1) measured by differential scanning calorimetry (DSC) is 81.39 °C and 74.34 °C, respectively, for ASC-B and ASC-S. Bone collagen has higher thermal resistance than skin collagen. Surface morphology imaged using a scanning electron microscope (SEM) showed that the bone collagen had a denser network structure, whilst the skin collagen was more fibrous and porous. The findings suggest that eel-derived collagens from skin and bone can serve as potential alternatives in the food, cosmetic, and healthcare industries.This research was funded by the “Study and Application of Anti-freezing Denaturation in Aquatic Frozen Foods” project (KH230175A)
Towards Hard-Positive Query Mining for DETR-based Human-Object Interaction Detection
Human-Object Interaction (HOI) detection is a core task for high-level image
understanding. Recently, Detection Transformer (DETR)-based HOI detectors have
become popular due to their superior performance and efficient structure.
However, these approaches typically adopt fixed HOI queries for all testing
images, which is vulnerable to the location change of objects in one specific
image. Accordingly, in this paper, we propose to enhance DETR's robustness by
mining hard-positive queries, which are forced to make correct predictions
using partial visual cues. First, we explicitly compose hard-positive queries
according to the ground-truth (GT) position of labeled human-object pairs for
each training image. Specifically, we shift the GT bounding boxes of each
labeled human-object pair so that the shifted boxes cover only a certain
portion of the GT ones. We encode the coordinates of the shifted boxes for each
labeled human-object pair into an HOI query. Second, we implicitly construct
another set of hard-positive queries by masking the top scores in
cross-attention maps of the decoder layers. The masked attention maps then only
cover partial important cues for HOI predictions. Finally, an alternate
strategy is proposed that efficiently combines both types of hard queries. In
each iteration, both DETR's learnable queries and one selected type of
hard-positive queries are adopted for loss computation. Experimental results
show that our proposed approach can be widely applied to existing DETR-based
HOI detectors. Moreover, we consistently achieve state-of-the-art performance
on three benchmarks: HICO-DET, V-COCO, and HOI-A. Code is available at
https://github.com/MuchHair/HQM.Comment: Accepted by ECCV202
Hybrid metallic nanoparticles for excitation of surface plasmon resonance
A Ag nanostructure was put forward in this paper. There are two types of Ag nanoparticles, spherical and pyramidal particles. Both of them have the same period, but different height and shapes. The hybrid nanoparticles can produce the localized surface plasmon resonance (LSPR), which couples each other and leads to an extra peak transmission. Our UV-visible-IR spectrophotometer measurement results show that some extra small and sharp peaks appear besides the normal LSPR wave peaks in the transmittance spectrum. The hybrid Ag nanoparticles being used as nanosensors will be more sensitive and selective than the conventional LSPR-based nanosensors. © 2007 American Institute of Physics
Accumulation of cinnamic acid and vanillin in eggplant root exudates and the relationship with continuous cropping obstacle
The contents of cinnamic acid and vanillin in eggplant root exudates and soil were determined by HPLC. The results showed that cinnamic acid and vanillin might remain in soil after the root of eggplant is released. With the extending growth stage and planting year of eggplant, the contents in root exudates, rhizosphere and continuous cropping soil increased. In bioassay and field studies, the allelopathy of cinnamic acid and vanillin to the verticillium wilt (V. dahliae) and the eggplant was observed, and when the concentration of cinnamic acid or vanillin was at 1 and 4mmol ⇦ -1, it inhibited the eggplant growth, while the occurrence of verticillium wilt was promoted. A high concentration of cinnamic acid and vanillin caused eggplant autotoxicity and increased the risk of disease infection, which finally led to continuous cropping obstacle.Keywords: Cinnamic acid, vanillin, root exudates, soil, verticillium wilt, continuous cropping obstacl
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