SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Liu Junwei) "

Sökning: WFRF:(Liu Junwei)

  • Resultat 1-10 av 13
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Ge, Xiaodong, et al. (författare)
  • Amelioration of type 2 diabetes by the novel 6, 8-guanidyl luteolin quinone-chromium coordination via biochemical mechanisms and gut microbiota interaction
  • 2023
  • Ingår i: JOURNAL OF ADVANCED RESEARCH. - : Elsevier. - 2090-1232 .- 2090-1224. ; 46, s. 173-188
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: Luteolin is a plant-derived flavonoid that exhibits a broad range of pharmacological activ-ities. Studies on luteolin have mainly focused on its use for hyperlipidaemia prevention, whereas the capacity of the flavonoid to hinder hyperglycaemia development remains underexplored.Objectives: To probe the anti-hyperglycemic mechanism of 6,8-guanidyl luteolin quinone-chromium coordination (GLQ.Cr), and to assess its regulatory effect on intestinal microbiota in type 2 diabetes mel-litus (T2DM) mice.Methods: High-sucrose/high-fat diet-induced and intraperitoneal injection of streptozotocin was used to develop a T2DM model. Glycometabolism related indicators, histopathology, and gut microbiota compo-sition in caecum samples were evaluated, and RNA sequencing (RNA-seq) of liver samples was con-ducted. Faecal microbiota transplantation (FMT) was further used to verify the anti-hyperglycemic activity of intestinal microbiota.Results: The administration of GLQ.Cr alleviated hyperglycaemia symptoms by improving liver and pan-creatic functions and modulating gut microbe communities (Lactobacillus, Alistipes, Parabacteroides, Lachnoclostridium, and Desulfovibrio). RNA-seq analysis showed that GLQ.Cr mainly affected the peroxi-some proliferative activated receptor (PPAR) signalling pathway in order to regulate abnormal glucose metabolism. FMT significantly modulated the abundance of Lactobacillus, Alloprevotella, Alistipes, Bacteroides, Ruminiclostridium, Brevundimonas and Pseudomonas in the caecum to balance blood glucose levels and counteract T2DM mice inflammation.Conclusion: GLQ.Cr improved the abnormal glucose metabolism in T2DM mice by regulating the PPAR signalling pathway and modulating intestinal microbial composition. FMT can improve the intestinal microecology of the recipient and in turn ameliorate the symptoms of T2DM-induced hyperglycaemia.
  •  
2.
  • Liu, Junwei, et al. (författare)
  • Polymer synergy for efficient hole transport in solar cells and photodetectors
  • 2023
  • Ingår i: Energy & Environmental Science. - : ROYAL SOC CHEMISTRY. - 1754-5692 .- 1754-5706.
  • Tidskriftsartikel (refereegranskat)abstract
    • Hole transport materials (HTMs) have greatly advanced the progress of solution-based electronic devices in the past few years. Nevertheless, most devices employing dopant-free organic HTMs can only deliver inferior performance. In this work, we introduced a novel "polymer synergy" strategy to develop versatile dopant-free polymer HTMs for quantum dot/perovskite solar cells and photodetectors. With this synergy strategy, the optical, electrical and aggregation properties of polymer HTMs can be modulated, resulting in complementary absorption, high hole mobility, favorable energy landscape and moderate aggregation. Moreover, a clear orientational transition was observed for the developed HTMs with a 9-fold increase in the face-on/edge-on ratio, providing a highway-like carrier transport for electronic devices, as revealed by in situ characterization and ultrafast transient absorption. With these benefits, the photovoltaic and photodetection performance of quantum dot devices were boosted from 11.8% to 13.5% and from 2.95 x 10(12) to 3.41 x 10(13) Jones (over a 10-fold increase), respectively. Furthermore, the developed polymer HTMs can also significantly enhance the photovoltaic and photodetection performance of perovskite devices from 15.1% to 22.7% and from 2.7 x 10(12) to 2.17 x 10(13)Jones with the same device structure, indicating their great application potential in the emerging optoelectronics.
  •  
3.
  • Liu, Nian, et al. (författare)
  • Multi-grained Temporal Prototype Learning for Few-shot Video Object Segmentation
  • 2023
  • Ingår i: 2023 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION (ICCV 2023). - : IEEE COMPUTER SOC. - 9798350307184 - 9798350307191 ; , s. 18816-18825
  • Konferensbidrag (refereegranskat)abstract
    • Few-Shot Video Object Segmentation (FSVOS) aims to segment objects in a query video with the same category defined by a few annotated support images. However, this task was seldom explored. In this work, based on IPMT, a state-of-the-art few-shot image segmentation method that combines external support guidance information with adaptive query guidance cues, we propose to leverage multi-grained temporal guidance information for handling the temporal correlation nature of video data. We decompose the query video information into a clip prototype and a memory prototype for capturing local and long-term internal temporal guidance, respectively. Frame prototypes are further used for each frame independently to handle fine-grained adaptive guidance and enable bidirectional clip-frame prototype communication. To reduce the influence of noisy memory, we propose to leverage the structural similarity relation among different predicted regions and the support for selecting reliable memory frames. Furthermore, a new segmentation loss is also proposed to enhance the category discriminability of the learned prototypes. Experimental results demonstrate that our proposed video IPMT model significantly outperforms previous models on two benchmark datasets. Code is available at https://github.com/nankepan/VIPMT.
  •  
4.
  • Zhang, Junwei, et al. (författare)
  • Asynchronous multiple access in visible light communication system based on DFT spread OFDM/OQAM
  • 2015
  • Ingår i: Asia Communications and Photonics Conference, ACPC 2015. - Washington, D.C. : Optical Society of America (OSA). - 9781943580064
  • Konferensbidrag (refereegranskat)abstract
    • A multiuser asynchronous visible light communication system adopting DFT spread (DFS-) OFDM/OQAM is proposed and experimentally demonstrated. Both high spectral locality and low peak-to-average power ratio are achieved with DFTS-OFDM/OQAM, which improves system’s transmission performance. 
  •  
5.
  • Feng, Kui, et al. (författare)
  • Fused Bithiophene Imide Dimer-Based n-Type Polymers for High-Performance Organic Electrochemical Transistors
  • 2021
  • Ingår i: Angewandte Chemie International Edition. - : WILEY-V C H VERLAG GMBH. - 1433-7851 .- 1521-3773. ; 60:45, s. 24198-24205
  • Tidskriftsartikel (refereegranskat)abstract
    • The development of n-type organic electrochemical transistors (OECTs) lags far behind their p-type counterparts. In order to address this dilemma, we report here two new fused bithiophene imide dimer (f-BTI2)-based n-type polymers with a branched methyl end-capped glycol side chain, which exhibit good solubility, low-lying LUMO energy levels, favorable polymer chain orientation, and efficient ion transport property, thus yielding a remarkable OECT electron mobility (mu(e)) of up to approximate to 10(-2) cm(2) V-1 s(-1) and volumetric capacitance (C*) as high as 443 F cm(-3), simultaneously. As a result, the f-BTI2TEG-FT-based OECTs deliver a record-high maximum geometry-normalized transconductance of 4.60 S cm(-1) and a maximum mu C* product of 15.2 F cm(-1) V-1 s(-1). The mu C* figure of merit is more than one order of magnitude higher than that of the state-of-the-art n-type OECTs. The emergence of f-BTI2TEG-FT brings a new paradigm for developing high-performance n-type polymers for low-power OECT applications.
  •  
6.
  • Li, Jiahui, et al. (författare)
  • Pseudocapacitive Heteroatom-Doped Carbon Cathode for Aluminum-Ion Batteries with Ultrahigh Reversible Stability
  • 2024
  • Ingår i: Energy & Environmental Materials. - : WILEY. - 2575-0356.
  • Tidskriftsartikel (refereegranskat)abstract
    • Aluminum (Al)-ion batteries have emerged as a potential alternative to conventional ion batteries that rely on less abundant and costly materials like lithium. Nonetheless, given the nascent stage of advancement in Al-ion batteries (AIBs), attaining electrode materials that can leverage both intercalation capacity and structural stability remains challenging. Herein, we demonstrate a C3N4-derived layered N,S heteroatom-doped carbon, obtained at different pyrolysis temperatures, as a cathode material for AIBs, encompassing the diffusion-controlled intercalation and surface-induced capacity with ultrahigh reversibility. The developed layered N,S-doped corbon (N,S-C) cathode, synthesized at 900 degrees C, delivers a specific capacity of 330 mAh g(-1) with a relatively high coulombic efficiency of similar to 85% after 500 cycles under a current density of 0.5 A g(-1). Owing to its reinforced adsorption capability and enlarged interlayer spacing by doping N and S heteroatoms, the N,S-C900 cathode demonstrates outstanding energy storage capacity with excellent rate performance (61 mAh g(-1) at 20 A g(-1)) and ultrahigh reversibility (90 mAh g(-1) at 5 A g(-1) after 10 000 cycles).
  •  
7.
  • Li, Long, et al. (författare)
  • Discriminative Co-Saliency and Background Mining Transformer for Co-Salient Object Detection
  • 2023
  • Ingår i: 2023 IEEE/CVF CONFERENCE ON COMPUTER VISION AND PATTERN RECOGNITION, CVPR. - : IEEE COMPUTER SOC. - 9798350301298 - 9798350301304 ; , s. 7247-7256
  • Konferensbidrag (refereegranskat)abstract
    • Most previous co-salient object detection works mainly focus on extracting co-salient cues via mining the consistency relations across images while ignore explicit exploration of background regions. In this paper, we propose a Discriminative co-saliency and background Mining Transformer framework (DMT) based on several economical multi-grained correlation modules to explicitly mine both co-saliency and background information and effectively model their discrimination. Specifically, we first propose a region-to-region correlation module for introducing inter-image relations to pixel-wise segmentation features while maintaining computational efficiency. Then, we use two types of pre-defined tokens to mine co-saliency and background information via our proposed contrast-induced pixel-to-token correlation and co-saliency token-to-token correlation modules. We also design a token-guided feature refinement module to enhance the discriminability of the segmentation features under the guidance of the learned tokens. We perform iterative mutual promotion for the segmentation feature extraction and token construction. Experimental results on three benchmark datasets demonstrate the effectiveness of our proposed method. The source code is available at: https://github.com/dragonlee258079/DMT.
  •  
8.
  • Li, Long, et al. (författare)
  • Robust Perception and Precise Segmentation for Scribble-Supervised RGB-D Saliency Detection
  • 2024
  • Ingår i: IEEE Transactions on Pattern Analysis and Machine Intelligence. - : IEEE COMPUTER SOC. - 0162-8828 .- 1939-3539. ; 46:1, s. 479-496
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper proposes a scribble-based weakly supervised RGB-D salient object detection (SOD) method to relieve the annotation burden from pixel-wise annotations. In view of the ensuing performance drop, we summarize two natural deficiencies of the scribbles and try to alleviate them, which are the weak richness of the pixel training samples (WRPS) and the poor structural integrity of the salient objects (PSIO). WRPS hinders robust saliency perception learning, which can be alleviated via model design for robust feature learning and pseudo labels generation for training sample enrichment. Specifically, we first design a dynamic searching process module as a meta operation to conduct multi-scale and multi-modal feature fusion for the robust RGB-D SOD model construction. Then, a dual-branch consistency learning mechanism is proposed to generate enough pixel training samples for robust saliency perception learning. PSIO makes direct structural learning infeasible since scribbles can not provide integral structural supervision. Thus, we propose an edge-region structure-refinement loss to recover the structural information and make precise segmentation. We deploy all components and conduct ablation studies on two baselines to validate their effectiveness and generalizability. Experimental results on eight datasets show that our method outperforms other scribble-based SOD models and achieves comparable performance with fully supervised state-of-the-art methods.
  •  
9.
  • Liu, Lindong, et al. (författare)
  • Intelligent simulation experimental study on influence of air velocity of air supply hood and exhaust hood with vertical push-pull ventilation
  • 2019
  • Ingår i: Journal of Intelligent & Fuzzy Systems. - : IOS PRESS. - 1064-1246 .- 1875-8967. ; 37:4, s. 4819-4826
  • Tidskriftsartikel (refereegranskat)abstract
    • The occupational health and safety problems caused by indoor dust and toxic gases in industrial plants are becoming increasingly serious. Vertical push-pull ventilation can effectively control dust and toxic gases and avoid indoor environmental pollution. The velocity of the air supply hood and exhaust hood in the push-pull ventilation intelligent device directly affects the control effect of the dust and toxic gases. However, no scholar has given a reasonable ratio of the air supply and exhaust velocity of the vertical push-pull ventilation device. Therefore, this paper uses the combination of Fluent numerical simulation technology and smoke visualization experiment to explore the best ratio of the air supply and exhaust velocity in the push-pull ventilation flow field. The research shows that the traces of the wind flow obtained by numerical analysis under different k which is the ratio of the air supply and exhaust velocity is consistent with the traces of visualized smoke in the actual experiment; The optimal ratio of air supply and exhaust is k = 1.75, which can effectively guarantee the indoor environment, occupational health and work efficiency of the operators.
  •  
10.
  • Liu, Xintao, et al. (författare)
  • Analysis of urban agglomeration structure through spatial network and mobile phone data
  • 2021
  • Ingår i: Transactions in GIS. - : Wiley. - 1361-1682 .- 1467-9671. ; 25:4, s. 1949-1969
  • Tidskriftsartikel (refereegranskat)abstract
    • Urban agglomeration is an important strategy used to promote economic development and urbanization in China. Understanding the structure of urban agglomeration is therefore essential for policy-makers and planners. In this study, the Beijing–Tianjin–Hebei urban agglomeration (BTHUG) is explored through a proposed spatial network analytical framework and a large mobile phone data set (over 20 million users). We first construct a weight-directed spatial interaction network based on an origin–destination matrix derived from the data set. Several network metrics (i.e., degree, strength, the rich-club coefficient, and the assortativity coefficient) and three selected community detection algorithms (i.e., Infomap, Louvain, and Regionalization) are applied and compared to reveal the structure of the BTHUG. A four-level hierarchical structure is defined and observed: one global center, two local centers, major cities that have low mobility flow but strong linkages with the three centers, and peripheral cities that have low mobility flow and weak linkages with the three centers. In particular, the results imply that the spatial structure of the BTHUG is over-dependent on the global center (i.e., Beijing and northern Langfang). Further, ignoring spatial interaction patterns in top-down administrative planning for urban agglomeration may lead to ineffective integrated development. The implications for BTHUG planning are discussed.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 13

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy