13,537 research outputs found
A GaN-based wireless power and information transmission method using Dual-frequency Programmed Harmonic Modulation
Information transmission is often required in power transfer to implement control. In this paper, a Dual-Frequency Programmed Harmonic Modulation (DFPHM) method is proposed to transfer two frequencies carrying power and information with the single converter via a common inductive coil. The proposed method reduces the number of injection tightly coupled transformers used to transmit information, thereby simplifying the system structure and improving reliability. The performances of power and information transmission, and the method of information modulation and demodulation, as well as the principles of the control, are analyzed in detail. Then a simulation model is set up to verify the feasibility of the method. In addition, an experiment platform is established to verify that the single converter can transfer the power and information simultaneously via a common inductive coil without using tightly coupled transformers.Web of Science8498564984
A CROSS-SECTIONAL STUDY OF KNEE FLEXION SPEED IN CHINESE CHILDREN DURING GROWTH
INTRODUCTION: In recent years, some research has been done on the relationship between the revolving speed of the adults` knee angles and sports achievements (Sheng, 1992; 1989; 1995). However, there is little information concerning this issue in children. The purpose of this study was to explore the developing regularity of the flexion speed of children’s knee angles across age
Difference or Indifference: China's Development Assistance Unpacked
China's growing role in international development through so?called ‘South–South cooperation’ has attracted considerable global attention. This article aims to provide a nuanced understanding of the nature of foreign aid policies implemented by China and help facilitate a new set of dialogues between China and more established providers of aid. It unpacks the developmental side of the story by first analysing the official discourse of Chinese aid in a historical context and thereafter examines the practice of conditional aid in relation to the Chinese emphasis on non?interference and mutual interest. The empirical basis for this article is largely derived from field studies undertaken in Malawi, Tanzania and Zimbabwe. We argue that although centrally controlled, Chinese aid has been consistently developmental, reflecting both the country's own development path and, to a lesser extent, international developmental goals
Offset Learning based Channel Estimation for IRS-Assisted Indoor Communication
The system capacity can be remarkably enhanced with the help of intelligent reflecting surface (IRS) which has been recognized as a advanced breaking point for the beyond fifth-generation (B5G) communications. However, the accuracy of IRS channel estimation restricts the potential of IRS-assisted multiple input multiple output (MIMO) systems. Especially, for the resource-limited indoor applications which typically contains lots of parameters estimation calculation and is limited by the rare pilots, the practical applications encountered severe obstacles. Previous works takes the advantages of mathematical-based statistical approaches to associate the optimization issue, but the increasing of scatterers number reduces the practicality of statistical approaches in more complex situations. To obtain the accurate estimation of indoor channels with appropriate piloting overhead, an offset learning (OL)-based neural network method is proposed. The proposed estimation method can trace the channel state information (CSI) dynamically with non-prior information, which get rid of the IRS-assisted channel structure as well as indoor statistics. Moreover, a convolution neural network (CNN)-based inversion is investigated. The CNN, which owns powerful information extraction capability, is deployed to estimate the offset, it works as an offset estimation operator. Numerical results show that the proposed OL-based estimator can achieve more accurate indoor CSI with a lower complexity as compared to the benchmark schemes
Protective effect of quercetin on bupivacaine-induced neurotoxicity via T-type calcium channel inhibition
Purpose: To determine the effect of quercetin on bupivacaine-induced neurotoxicity and to investigate the mechanisms involved.Methods: Cultured SH-SY5Y cells were divided into five treatment groups: control group with no drug, bupivacaine treatment group, quercetin group, bupivacaine--quercetin combination treatment group, and bupivacaine-mibefradil combination treatment group. Cell morphology in each group was examined by microscopy while cell viability was assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2- tetrazolium bromide (MTT) assay after 24 h incubation. Cytosolic calcium ion concentration was determined by flow cytometry while Cav3.1 protein expression was evaluated by western blot.Results: Quercetin (50 μM) significantly (p < 0.05) protected SH-SYS5 cells from bupivacaine-induced cell apoptosis and also significantly reduced intracellular calcium ion concentration (p < 0.01) by approximately 40 %. Cav3.1 protein expression was normalized following quercetin treatment.Conclusion: These results show that quercetin reduces the neurotoxicity induced by bupivacaine, possibly through inhibition of T-type calcium channel. This finding implies a novel mechanism for neuroprotective effect of quercetin, and its potential for treating toxicity arising from the use of local anesthetic agents.Keywords: Quercetin, Bupivacaine, Local anaesthetic, Neuroprotection, Neurotoxicity, T-type calcium channe
3DPortraitGAN: Learning One-Quarter Headshot 3D GANs from a Single-View Portrait Dataset with Diverse Body Poses
3D-aware face generators are typically trained on 2D real-life face image
datasets that primarily consist of near-frontal face data, and as such, they
are unable to construct one-quarter headshot 3D portraits with complete head,
neck, and shoulder geometry. Two reasons account for this issue: First,
existing facial recognition methods struggle with extracting facial data
captured from large camera angles or back views. Second, it is challenging to
learn a distribution of 3D portraits covering the one-quarter headshot region
from single-view data due to significant geometric deformation caused by
diverse body poses. To this end, we first create the dataset
360{\deg}-Portrait-HQ (360{\deg}PHQ for short) which consists of high-quality
single-view real portraits annotated with a variety of camera parameters (the
yaw angles span the entire 360{\deg} range) and body poses. We then propose
3DPortraitGAN, the first 3D-aware one-quarter headshot portrait generator that
learns a canonical 3D avatar distribution from the 360{\deg}PHQ dataset with
body pose self-learning. Our model can generate view-consistent portrait images
from all camera angles with a canonical one-quarter headshot 3D representation.
Our experiments show that the proposed framework can accurately predict
portrait body poses and generate view-consistent, realistic portrait images
with complete geometry from all camera angles
Erratum for “Protective effect of quercetin on bupivacaineinduced neurotoxicity via T-type calcium channel inhibition”
Jin et al Trop J Pharm Res 2017, 16(8): 1827-1833 http://dx.doi.org/10.4314/tjpr.v16i8.11The correct name of the First Author is Zhao as provided above and not Chao earlier published.Citation: Jin Z, Wu H, Tang C, Ke J, Wang Y. Protective effect of quercetin on bupivacaineinduced neurotoxicity via T-type calcium channel inhibition. Trop J Pharm Res 2017; 16(8):1827-1833 Erratum: 2017; 16(9):2051 http://dx.doi.org/10.4314/tjpr.v16i9.
Camera geolocation using digital elevation models in hilly area
he geolocation of skyline provides an important application in unmanned vehicles, unmanned aerial vehicles, and other fields. However, the existing methods are not effective in hilly areas. In this paper, we analyze the difficulties to locate in hilly areas and propose a new geolocation method. According to the vegetation in hilly area, two new skyline features, enhanced angle chain code and lapel point, are proposed. In order to deal with the skyline being close to the camera, we also propose a matching method which incorporates skyline distance heatmap and skyline pyramid. The experimental results show that the proposed method is highly effective in hilly area and has a robust performance against noise and rotation effects
A novel rapid method for viewshed computation on DEM through max-pooling and min-expected height
Viewshed computation of a digital elevation model (DEM) plays an important role in a geographic information system, but the required high computational time is a serious problem for a practical application. Hitherto, the mainstream methods of viewshed computing include line-of-sight method, reference planes method, etc. Based on these classical algorithms, a new algorithm for viewshed computation is proposed in this paper: the Matryoshka doll algorithm. Through a pooling operation, the minimum expected height of the DEM is introduced as max-pooling with minimum expected height in the viewshed computing optimization. This is to increase the efficiency and adaptability of the computation of the visibility range. The experimental results demonstrate that the algorithm has obvious advantages in computing speed, but with the accuracy only slightly reduced
- …