2,408 research outputs found

    Lightweight Vision Transformer with Cross Feature Attention

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    Recent advances in vision transformers (ViTs) have achieved great performance in visual recognition tasks. Convolutional neural networks (CNNs) exploit spatial inductive bias to learn visual representations, but these networks are spatially local. ViTs can learn global representations with their self-attention mechanism, but they are usually heavy-weight and unsuitable for mobile devices. In this paper, we propose cross feature attention (XFA) to bring down computation cost for transformers, and combine efficient mobile CNNs to form a novel efficient light-weight CNN-ViT hybrid model, XFormer, which can serve as a general-purpose backbone to learn both global and local representation. Experimental results show that XFormer outperforms numerous CNN and ViT-based models across different tasks and datasets. On ImageNet1K dataset, XFormer achieves top-1 accuracy of 78.5% with 5.5 million parameters, which is 2.2% and 6.3% more accurate than EfficientNet-B0 (CNN-based) and DeiT (ViT-based) for similar number of parameters. Our model also performs well when transferring to object detection and semantic segmentation tasks. On MS COCO dataset, XFormer exceeds MobileNetV2 by 10.5 AP (22.7 -> 33.2 AP) in YOLOv3 framework with only 6.3M parameters and 3.8G FLOPs. On Cityscapes dataset, with only a simple all-MLP decoder, XFormer achieves mIoU of 78.5 and FPS of 15.3, surpassing state-of-the-art lightweight segmentation networks.Comment: Technical Repor

    Weak cosmic censorship conjecture for the novel 4D4D charged Einstein-Gauss-Bonnet black hole with test scalar field and particle

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    Recent researches of the novel 4D4D Einstein-Gauss-Bonnet (EGB) gravity have attracted great attention. In this paper, we investigate the validity of the weak cosmic censorship conjecture for a novel 4D4D charged EGB black hole with test charged scalar field and test charged particle respectively. For the test charged field scattering process, we find that both extremal and near-extremal black holes cannot be overcharged. For the test charged particle injection, to first order, an extremal black hole cannot be overcharged while a near-extremal 4D4D charged EGB black hole can be destroyed. To second order, however, both extremal and near-extremal 4D4D charged EGB black holes can be overcharged for positive Gauss-Bonnet coupling constant; for negative Gauss-Bonnet coupling constant, an extremal black hole cannot be overcharged and the validity of the weak cosmic censorship conjecture for a near-extremal black hole depends on the Gauss-Bonnet coupling constant.Comment: 13 pages,1 figure;V2: discussions and references added; V3: published versio

    Photodynamic therapy combined with the Sanqi Panax Notoginseng for patients with age-related macular degeneration and choroidal neovascularization

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    AIM: To investigate the clinical effect of photodynamic therapy(PDT)combined with Traditional Chinese medicine Sanqi Panax Notoginseng therapy for age-related macular degeneration(AMD)and choroidal neovascularization(CNV). <p>METHODS: Seventeen patients(17 eyes)with AMD and CNV were diagnosed by visual acuity, ocular pressure, fundus fluorescein angiography(FFA), idocyanine green angiography(ICGA)and optic coherence tomography(OCT), and male 7 cases, female 10 cases, age 53-72 years old. PDT was performed using the recommended standard procedure. The patients were treated with PDT for 5 days, and Sanqi Panax Notoginseng 500mg injection by intravenous drip for 10 days, once a day, 15 days as one course. One month, 3, 6 months of follow-up after treatment. <p>RESULTS: Of 17 patients after 6 months treatment, visual acuity improved in 8 cases(47%, 8/17), remained stable in 6 cases(35%), and decreased in 3 cases(18%); and 12 cases(71%)with CNV closure and leakage stopped completely, 5 cases(29%)with most of the CNV's closure, 1 patient experienced blurred vision. <p>CONCLUSION: The results show that PDT combined with traditional Chinese medicine Sanqi Panax Notoginseng in treatment of ADM-CNV is simple and has reliable effect, it can be used in clinical application

    Effects of apelin and vascular endothelial growth factor on central retinal vein occlusion in monkey eyes intravitreally injected with bevacizumab: a preliminary study

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    Purpose: To examine the intraocular distribution of bevacizumab at four weeks after intravitreal bevacizumab (IVB) injection and to investigate the effects of IVB on apelin and vascular endothelial growth factor (VEGF) in the central retinal vein occlusion (CRVO) of monkey eyes. Methods: Direct laser coagulation was performed on all branch retinal veins in the right eyes of six Rhesus monkeys to establish a CRVO model. The eyes of the first three monkeys were enucleated one week, two weeks, and 24 weeks after the establishment of the CRVO model; this was the CRVO group. Subsequently, IVB was injected into the eyes of the last three monkeys one week, two weeks, and 24 weeks after laser coagulation; this was the IVB group. The left eye of the first monkey was used as normal control. Immunohistochemistry and reverse-transcription PCR was used to examine the expression of apelin and VEGF. The penetration of bevacizumab into the retina and iris was investigated by fluorescence immunostaining. Results: Immunoreactivity for bevacizumab could be detected in the vessel walls of the iris and choroid on day 28 after injecting IVB: apelin and VEGF staining had been more prominent than normal in the CRVO eye, but these decreased following IVB injection. Expression of apelin mRNA (p&lt;0.01) was lower in the IVB group than the CRVO group and did not vary significantly between groups. Conclusions: Bevacizumab could be detected in the iris and choroid after four weeks of intravitreal injection. Apelin may be partially suppressed by bevacizumab, and it may play a role in retinal neovascularization during the development of CRVO.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000289983700001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Biochemistry &amp; Molecular BiologyOphthalmologySCI(E)PubMed10ARTICLE1171044-10541

    Searching for Majorana Neutrinos at a Same-Sign Muon Collider

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    Majorana properties of neutrinos have long been a focus in the pursuit of possible new physics beyond the standard model, which has motivated lots of dedicated theoretical and experimental studies. A future same-sign muon collider is an ideal platform to search for Majorana neutrinos through the Lepton Number Violation process. Specifically, this t-channel kind of process is less kinematically suppressed and has a good advantage in probing Majorana neutrinos at high mass regions up to 10 TeV. In this paper, we perform a detailed fast Monte Carlo simulation study through examining three different final states: 1) pure-leptonic state with electrons or muons, 2) semi-leptonic state, and 3) pure-hadronic state in the resolved or merged categories. Furthermore, we perform a full simulation study on the pure-leptonic final state to validate our fast simulation results.Comment: 15 pages, 8 figure

    Electronic transmission in Graphene suppressed by interlayer interference

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    We investigate electronic transport property of a graphene monolayer covered by a graphene nanoribbon. We demonstrate that electronic transmission of a monolayer can be reduced when covered by a nanoribbon. The transmission reduction occurs at different energies determined by the width of nanoribbon. We explain the transmission reduction by using interference between wavefunctions in the monolayer and the nanoribbon. Furthermore, we show the transmission reduction of a monolayer is combinable when covered by more than one nanoribbon and propose a concept of "combination of control" for nano-application design.Comment: 11 pages, 6 figure

    Field emission from randomly oriented ZnO nanowires

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    Randomly oriented zinc oxide (ZnO)nanowires with different diameters were synthesized on a large scale on silicon substrates through a simple physical evaporation method. The nanowires exhibit stable and uniform electron field emission, and the turn-on field reduces with the diameter decreasing. The perfect field emission ability of the ZnOnanowires may be related to their rough surface and sharp curvature. Considering the efficient synthesis method and their excellent field emission characteristics, the authors expect that the randomly oriented ZnOnanowire films could have a promising industrial prospect as economic emitters for flat panel displays.This project is financially supported by the National Natural Science Foundation of China No. 50502005 and Beijing Natural Science Foundation No. 1062008. One of the authors Y.Q.C. is supported by the Beijing Novel Program
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