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Sleeve bridging of the rhesus monkey ulnar nerve with muscular branches of the pronator teres: multiple amplification of axonal regeneration 被引量:3
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作者 Yu-hui Kou Pei-xun Zhang +6 位作者 Yan-hua Wang Bo Chen Na Han Feng Xue Hong-bo Zhang Xiao-feng Yin Bao-guo Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第1期53-59,共7页
Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previo... Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple ampli- fication of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple ampli- fication of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were su- tured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction veloc- ity reached 22.63 _+ 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 + 652 in the branches of pronator teres of donor, and 2,661 ~ 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons. 展开更多
关键词 nerve regeneration peripheral nerve rhesus monkey muscular branches of pronator teres ulnar nerve multiple amplification small gap sleeve bridging NSFC grants neural regeneration
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Large borehole with multi-lateral branches: A novel solution for exploitation of clayey silt hydrate 被引量:12
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作者 Yan-long Li Yi-zhao Wan +5 位作者 Qiang Chen Jia-xin Sun Neng-you Wu Gao-wei Hu Fu-long Ning Pei-xiao Mao 《China Geology》 2019年第3期333-341,共9页
Raising the in situ decomposition rate of natural gas hydrate and increasing the decomposition contact area are two main ways to raise the productivity of hydrate. An exploitation technique based on large borehole wit... Raising the in situ decomposition rate of natural gas hydrate and increasing the decomposition contact area are two main ways to raise the productivity of hydrate. An exploitation technique based on large borehole with multi-lateral branches (LB & MB) was proposed in this paper. This technique is mainly intended for the clayey silt hydrate reservoir in the South China Sea, and its main purpose is to alleviate the sand output from formation for maintaining the stability of the reservoir and to greatly increase the gas productivity of the reservoir. In this paper, the following aspects were mainly expounded: definition of the basic geometric parameters for layout of multi-lateral branches in clayey silt hydrate reservoir, simulation of the stimulation effect of a typical well profile with two branches, and prediction and simulation of the reservoir failure risk in a well profile with eight branches. The results show that the LB & MB effectively improves the flow field in the formation, raises the productivity of the reservoir and may also help to decrease the produced water-gas ratio (WGR). When the lateral branches spacing is too small, the failure zones around adjacent lateral branches overlap each other, possibly causing reservoir failure in a larger range. Therefore, the geometric parameters of multi-lateral branches depend on the dual control of the productivity and geotechnical risk factor of reservoir. Further study is being carried out, so as to obtain the optimal combination of parameters of multi-lateral branches. 展开更多
关键词 Natural gas HYDRATE Clayey SILT multi-lateral branches STIMULATION Numerical simulation HYDRATE exploration engineering South China Sea China
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Effect of Long Chain Branches of High Melt Strength Polypropylene on Its Supercritical CO_(2)Foaming Behavior
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作者 Ruiheng He Zilong Lv +3 位作者 Jichun Jiang Fangfei Xing Tao Liu Shicheng Zhao 《Carbon and Hydrogen》 2025年第2期214-225,共12页
Polypropylene(PP)has a relatively low melt strength due to its linear structure,which seriously limits its supercritical CO_(2)foaming performance.Introducing long-chain branches(LCBs)via grafting can significantly en... Polypropylene(PP)has a relatively low melt strength due to its linear structure,which seriously limits its supercritical CO_(2)foaming performance.Introducing long-chain branches(LCBs)via grafting can significantly enhance its melt strength.However,the relationship between the LCB level of high melt strength polypropylene(HMSPP)and its foaming behavior remains unclear.In this study,a series of HMSPP with different LCB levels was prepared using vinyl polydimethylsiloxane(VS)of varying viscosities as grafting monomers to investigate this relationship.Rheological analysis showed that the increase in viscosity of VS led to higher LCB levels in HMSPP.The melt strength of HMSPP increases with the increase of LCB levels,reaching up to 0.62 N,which is 13 times higher than that of the raw material.Supercritical CO_(2)foaming results revealed that the expansion ratio of HMSPP first increased and then decreased with the increase of melt strength,reaching a maximum of 39.4 times.Combining experiments with simulations,the influence of LCB levels on the dissolution and diffusion behavior of CO_(2)in HMSPP was clarified.This study deepens the understanding of the relationship between LCB and the foaming behavior of HMSPP,providing valuable insights for designing HMSPP with optimized foaming properties. 展开更多
关键词 high melt strength polypropylene long-chain branches supercritica CO_(2)foaming
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Processability and Structure of Dynamically Modified Linear Low-density Polyethylene with Different Branching Contents Using a High Peroxide Content
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作者 Jun-Jin Duan Yan-Qin Huang +3 位作者 Fu-Qing Wei Yan Gao Fu-Shan Wang Jia-Chun Feng 《Chinese Journal of Polymer Science》 2026年第1期87-99,I0011,共14页
Dynamic melt modification of polyethylene via the direct grafting of peroxide fragments shows promise for the development of processable functionalized materials.In this study,four linear low-density polyethylenes(LLD... Dynamic melt modification of polyethylene via the direct grafting of peroxide fragments shows promise for the development of processable functionalized materials.In this study,four linear low-density polyethylenes(LLDPEs)with comparable molecular weights but different short-chain branch(SCB)contents(ranging of 5-66 per 1000 carbon atoms)were modified via dynamic melt mixing using 2 wt% benzoyl peroxide at 145℃ and 50 r/min for 30 min.The influence of SCB content on the processability and structure of the resulting products was systematically investigated.All modified products exhibited good melt processability with melt flow rates(MFR)ranging from 0.46 g/10min to 1.07 g/10min.Products derived from low-SCB LLDPEs showed a lower MFR,higher cross-linking content,a larger number of long-chain branches,and a higher degree of benzoyl grafting.In contrast,those produced from high-SCB LLDPEs exhibited improved processability,reduced cross-linking,fewer long-chain branches,and lower benzoyl grafting levels.A detailed structural investigation of the soluble and insoluble fractions,which were separated using trichlorobenzene fractionation,was conducted to analyze the structural features of various modified products and demonstrate that the SCB content(i.e.,tertiary carbon density)significantly influences radical coupling during dynamic modification.Elevated tertiary carbon density,by introducing greater steric hindrance,suppresses radical coupling during dynamic modification,thereby reducing the efficiency of both crosslinking and peroxide fragment grafting.These findings provide new insights into the structure-reactivity relationships in peroxide-induced polyethylene modification and lay the foundation for tailoring material properties via dynamic processing. 展开更多
关键词 POLYETHYLENE PEROXIDE Short-chain branching Dynamical modification PROCESSABILITY
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Face-Pedestrian Joint Feature Modeling with Cross-Category Dynamic Matching for Occlusion-Robust Multi-Object Tracking
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作者 Qin Hu Hongshan Kong 《Computers, Materials & Continua》 2026年第1期870-900,共31页
To address the issues of frequent identity switches(IDs)and degraded identification accuracy in multi object tracking(MOT)under complex occlusion scenarios,this study proposes an occlusion-robust tracking framework ba... To address the issues of frequent identity switches(IDs)and degraded identification accuracy in multi object tracking(MOT)under complex occlusion scenarios,this study proposes an occlusion-robust tracking framework based on face-pedestrian joint feature modeling.By constructing a joint tracking model centered on“intra-class independent tracking+cross-category dynamic binding”,designing a multi-modal matching metric with spatio-temporal and appearance constraints,and innovatively introducing a cross-category feature mutual verification mechanism and a dual matching strategy,this work effectively resolves performance degradation in traditional single-category tracking methods caused by short-term occlusion,cross-camera tracking,and crowded environments.Experiments on the Chokepoint_Face_Pedestrian_Track test set demonstrate that in complex scenes,the proposed method improves Face-Pedestrian Matching F1 area under the curve(F1 AUC)by approximately 4 to 43 percentage points compared to several traditional methods.The joint tracking model achieves overall performance metrics of IDF1:85.1825%and MOTA:86.5956%,representing improvements of 0.91 and 0.06 percentage points,respectively,over the baseline model.Ablation studies confirm the effectiveness of key modules such as the Intersection over Area(IoA)/Intersection over Union(IoU)joint metric and dynamic threshold adjustment,validating the significant role of the cross-category identity matching mechanism in enhancing tracking stability.Our_model shows a 16.7%frame per second(FPS)drop vs.fairness of detection and re-identification in multiple object tracking(FairMOT),with its cross-category binding module adding aboute 10%overhead,yet maintains near-real-time performance for essential face-pedestrian tracking at small resolutions. 展开更多
关键词 Cross-category dynamic binding joint feature modeling face-pedestrian association multi object tracking occlusion robustness
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AI-driven integration of multi-omics and multimodal data for precision medicine
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作者 Heng-Rui Liu 《Medical Data Mining》 2026年第1期1-2,共2页
High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging ... High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1). 展开更多
关键词 high throughput transcriptomics multi omics single cell multimodal learning frameworks foundation models omics data modalitiesemerging ai driven precision medicine
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Intelligent integration and advancement of multi-organ-on-a-chip
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作者 Chen-Xi Song Lu Huang 《Biomedical Engineering Communications》 2026年第1期1-3,共3页
Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technol... Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technology overcomes the limitations of traditional single-organ models,providing a novel platform for investigating complex disease mechanisms and evaluating drug efficacy and toxicity.Although it demonstrates broad application prospects,its development still faces critical bottlenecks,including inadequate physiological coupling between organs,short functional maintenance durations,and limited real-time monitoring capabilities.Contemporary research is advancing along three key directions,including functional coupling,sensor integration,and full-process automation systems,to propel the technology toward enhanced levels of physiological relevance and predictive accuracy. 展开更多
关键词 investigating complex disease mechanisms emulate complex interactions multiple human organs vitro sensor integration intelligent integration predictive accuracy physiological coupling multi organ chip microfluidic systemsthis
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基于multi-branch的点云几何后处理方法
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作者 钱虞杰 丁丹丹 《杭州师范大学学报(自然科学版)》 2025年第6期664-672,共9页
基于几何的点云压缩(geometry-based point cloud compression,G-PCC)可有效降低点云传输对网络带宽和存储的要求,但重建后的点云质量常因点的消失而显著下降.文章提出了一种基于多分支(multi-branch)的G-PCC点云几何后处理方法,通过提... 基于几何的点云压缩(geometry-based point cloud compression,G-PCC)可有效降低点云传输对网络带宽和存储的要求,但重建后的点云质量常因点的消失而显著下降.文章提出了一种基于多分支(multi-branch)的G-PCC点云几何后处理方法,通过提取多尺度几何特征,并在每个尺度上使用基于k近邻的最大池化层来聚合几何邻域信息,从而预测体素块的概率,实现更精确的点云重建.在国际运动图像专家组(Moving Picture Experts Group,MPEG)推荐的通用测试条件下,该方法与G-PCC(octree)、G-PCC(trisoup)相比,平均获得91.89%(84.57%)和75.24%(73.51%)的D1(D2)BD-Rate增益;与传统方法LUT相比,平均获得76.78%(70.37%)的D1(D2)BD-Rate增益;与基于深度学习的方法DGPP相比,平均获得23.95%(21.41%)的BD-Rate增益.此外,该方法相较于现有基于学习的方法,复杂度更低,具有更广阔的应用前景. 展开更多
关键词 点云几何压缩 后处理 深度学习 多尺度 K近邻算法
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Analysis on the Composition and Structure of Branches of Two Kinds of Tree Shapes in Korla Fragrant Pear 被引量:2
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作者 成小龙 廖康 +4 位作者 李楠 赵世荣 孙慧瑛 曼苏尔.那斯尔 刘娟 《Agricultural Science & Technology》 CAS 2013年第7期954-958,共5页
ObjectiveThe thesis aims at investigating the distribution and structural characteristics of various branches in canopy of Korla fragrant pear. MethodStatistic work and analysis were conducted on the numbers and distr... ObjectiveThe thesis aims at investigating the distribution and structural characteristics of various branches in canopy of Korla fragrant pear. MethodStatistic work and analysis were conducted on the numbers and distribution characteristics of various branches in each cubic lattice by using the canopy cellular method. ResultThe results showed that: The total number of scaffold branches of evacuation layered tree shape was 97, which mainly distributed in the lower layer and middle part of the canopy; the total number of scaffold branches of open-center tree shape was 94, which mainly distributed in the lower layer and middle part of the canopy. The total number of annual branches of evacuation layered tree shape was 3 920, which mainly distributed in the middle layer and outer part of the canopy; and the total number of annual branches of the open-center tree shape was 3 183, which mainly distributed in middle layer and outer part of the canopy. The total number of perennial branches of evacuation layered tree shape was 2 184, which mainly distributed in lower layer and outer part of the canopy; the total number of perennial branches of open-center tree shape was 1 444, which mainly distributed in middle layer and outer part of the canopy. ConclusionThe total number and the distribution positions of scaffold branches in the canopy of each tree shape were basically the same. The total numbers of annual branches of the two kinds of tree shapes were different, but the distribution positions were basically the same. The total numbers and the distribution positions of perennial branches in the canopy of the two kinds of tree shapes were different. 展开更多
关键词 Korla fragrant pear Tree shape Composition and structure of branch
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Study on the Cutting Rooting of Syriga Microphylla with Tender Branches 被引量:1
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作者 武术杰 周秀华 《Agricultural Science & Technology》 CAS 2010年第11期37-38,81,共3页
[Objective] The study was carried out in order to find out the best method of rapid cutting rooting of Syriga microphylla with tender branches.[Method] Effect of rooting reagent with different concentrations on the ra... [Objective] The study was carried out in order to find out the best method of rapid cutting rooting of Syriga microphylla with tender branches.[Method] Effect of rooting reagent with different concentrations on the rapid cutting rooting of Syriga microphylla with tender branches was studied in our paper.[Result] There was great difference between cuttings with auxin and without auxin.[Conclusion] Tender branches treated by 90 mg/L indole butyric acid(IBA)had the best cutting rooting. 展开更多
关键词 Syriga microphylla Tender branches Cutting rooting Rooting reagent
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Anchorage properties at the interface between soil and roots with branches 被引量:8
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作者 Xiaodong Ji Lihua Chen Ao Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期83-93,共11页
Roots play an important role in stabilizing and strengthening soil. This article aims to study the mechanical properties of the interface between soil and roots with branches, using the pullout test method in the labo... Roots play an important role in stabilizing and strengthening soil. This article aims to study the mechanical properties of the interface between soil and roots with branches, using the pullout test method in the laboratory. The mechanical properties of the soil-root with branches interface is determined through the pullout-force and root-slippage curve (F-S curve). The results of investigating 24 Pinus tabulaeformis single roots and 55 P. tabulaeformis roots with branches demonstrated three kinds of pullout test failures: breakage failure on branching root, breakage failure on branching node, and pullout failure. The branch angle had a remarkable effect on the failure mode of the roots with branches: the maximum pullout force increased with the sum of the branch diameters and the branch angle. The peak slippage and the initial force had a positive correlation with the sum of the branch diameter. The sig- nificance test of correlation between branch angle and the initial force, however, showed they had no correlation. Branch angle and branch root diameter affect the anchorage properties between root system and soil. Therefore, it is important to investigate the anchorage mechanics of the roots with branches to understand the mechanism of root reinforcement and anchorage. 展开更多
关键词 Root-soil interface mechanics Pullout test method Root branches branch angle
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Study on the Metallogenetism of Sub-mantle Plume and Mantle Branches in the Gold Mineralization Concentration Area of Northwest Jiaodong Peninsula 被引量:4
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作者 NIU Shuyin CHENG Guangsuo +8 位作者 ZHANG Jianzhen SUN Aiqun MA Baojun ZHANG Fuxiang WANG Baode XU Meng WU Jichun ZHAO Rongxin WANG Shanfei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1409-1420,共12页
The northwest of Jiaodong peninsula is characterized by its greatest gold concentration area, enormous gold reserves and limited time interval (115±5Ma) of gold mineralization in China. Studies show that the ea... The northwest of Jiaodong peninsula is characterized by its greatest gold concentration area, enormous gold reserves and limited time interval (115±5Ma) of gold mineralization in China. Studies show that the east area of north China began its mantle plume evolution since the Yanshanian movement, and the Laiyang sub-mantle plume and its surrounding mantle branches such as those in Guojiadian, Aishan and Panshidian were formed in the mineralization concentration area of northwestern Jiaodong peninsula. With the development of mantle plume →sub-mantle plume → mantle branch→ favorable expending structures, the deep-derived hydrothermal fluid moved up to the favorable places, such as brittle-ductile or ductile-brittle shearing zones, the internal and external contact zones of intrusions, dense fracturing zones and the contact zones between dikes and countryrocks, and concentrated into deposits. Then the gold mineralization concentration zones that are centralized on mantle branches were formed. This study takes Guojiadian mantle branch as an example to discuss their metallogenetism and conclude the metallogenetic mode. 展开更多
关键词 sub-mantle plume mantle branch ore-controlling structure metallogenetism metallogenetic mode northwest Jiaodong peninsula
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Detection of long-chain branches in polyethylene via rheological measurements 被引量:2
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作者 Yun-Fan Mei Bao-Hua Guo Jun Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第4期588-592,共5页
The detection of long-chain branches(LCB) in polyethylene is of considerable importance as the processing properties of polyethylene are strongly affected by even a small amount of LCB. While the conventional charac... The detection of long-chain branches(LCB) in polyethylene is of considerable importance as the processing properties of polyethylene are strongly affected by even a small amount of LCB. While the conventional characterization techniques such as GPC-MALS and13 C NMR fail or take very long time to detect low content of LCB, we turn to the rheological method, which is more sensitive to LCB. In our study, we performed oscillatory shear test, creep test and stress relaxation test on two series of metallocene linear low density polyethylene(LLDPE), revealing that the resins with LCB show higher zero-shear-rate viscosity, retarded relaxation and higher flow activation energy than those without or with less LCB. The resins with LCB showed shear thinning at very low shear rate and their zero-shear-rate viscosities were obtained via creep test. The content of LCB was quantitatively estimated from the flow activation energy. In addition, the modulus-time curves during stress relaxation of melt of the different resins obeyed the power law. The exponent of the resins with more LCB was 0.7, different from that of the resins with less LCB, around 1.7. 展开更多
关键词 Metallocene polyethylene Long-chain branch RHEOLOGY Stress relaxation
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THE CONSTRUCTION OF MULTITYPE CANONICAL MARKOV BRANCHING CHAINS IN RANDOM ENVIRONMENTS 被引量:2
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期431-442,共12页
The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introd... The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introduces the concepts of the multitype canonical Markov branching chain in random environment (CMBCRE) and multitype Markov branching chain in random environment (MBCRE) and proved that CMBCRE must be MBCRE, and any MBCRE must be equivalent to another CMBCRE in distribution. The main results of this article are the construction of CMBCRE and some of its probability properties. 展开更多
关键词 Random Markov matrix Markov chain in random environment Markov branching chain in random environment canonical Markov branching chain in random environment generator random variables
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Branch-Activated Multi-Domain Convolutional Neural Network for Visual Tracking 被引量:2
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作者 CHEN Yimin LU Rongron +1 位作者 ZOU Yibo ZHANG Yanhui 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第3期360-367,共8页
Convolutional neural networks (CNNs) have been applied in state-of-the-art visual tracking tasks to represent the target. However, most existing algorithms treat visual tracking as an object-specific task. Therefore... Convolutional neural networks (CNNs) have been applied in state-of-the-art visual tracking tasks to represent the target. However, most existing algorithms treat visual tracking as an object-specific task. Therefore, the model needs to be retrained for different test video sequences. We propose a branch-activated multi-domain convolutional neural network (BAMDCNN). In contrast to most existing trackers based on CNNs which require frequent online training, BAMDCNN only needs offine training and online fine-tuning. Specifically, BAMDCNN exploits category-specific features that are more robust against variations. To allow for learning category-specific information, we introduce a group algorithm and a branch activation method. Experimental results on challenging benchmark show that the proposed algorithm outperforms other state-of-the-art methods. What's more, compared with CNN based trackers, BAMDCNN increases tracking speed. 展开更多
关键词 convolutional neural network(CNN) category-specific feature group algorithm branch activation method
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Activity maintenance of the excised branches and a case study of NO_2 exchange between the atmosphere and P.nigra branches 被引量:1
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作者 Chun Chen Yuzheng Wang +9 位作者 Yuanyuan Zhang Xiaoxiu Lun Chengtang Liu Yujing Mu Chenglong Zhang Pengfei Liu Chaoyang Xue Min Song Can Ye Junfeng Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第6期316-326,共11页
The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net ... The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net photosynthetic rate(NPR) of the excised branches and branches in situ were measured simultaneously by using two photosynthetic instruments to characterize the activity of the excised branches of Phyllostachys nigra. The ratio of normalized NPR of excised branches to NPR in situ was used to assess the photosynthetic activity of detached branches. Based on photosynthetic activity, an optimal hydroponics protocol for maintaining activity of excised P. nigra branches was presented:1/8 times the concentration of Gamborg B5 vitamin mixture with p H = 6. Under the best cultivation protocol, photosynthetic activity of excised P. nigra branches could be maintained more than 90% within 6 hr in the light intensity range of 200–2000 μmol/(m2·sec) and temperature range of 13.4–28.7°C. The nitrogen dioxide(NO2) flux differences between in situ and in vitro branches and the atmosphere were compared using double dynamic chambers.Based on the maintenance method of excised branches, the NO2 exchange flux between the excised P. nigra branches and the atmosphere(from-1.01 to-2.72 nmol/(m2·sec) was basically consistent with between the branches in situ and the atmosphere(from-1.12 to-3.16 nmol/(m2 sec)) within 6 hr. Therefore, this study provided a feasible protocol for in vitro measurement of gas exchange between tall trees and the atmosphere for a period of time. 展开更多
关键词 Excised branches ACTIVITY maintenance NO2 EXCHANGE flux HYDROPONICS Dynamic CHAMBER
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Photophysical Property of Photoactive Molecules with Multibranched Push-Pull Structures
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作者 王营营 马骁楠 +5 位作者 Silvije Vdovic 阎林胤 王雪飞 郭前进 夏安东 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期563-571,I0003,I0004,共11页
The structure-property characteristics of a series of newly synthesized intramolecular charge- transfer (ICT) compounds, single-branch monomer with triphenylmethane as electron donor and 2,1,3-benzothiadiazole as ac... The structure-property characteristics of a series of newly synthesized intramolecular charge- transfer (ICT) compounds, single-branch monomer with triphenylmethane as electron donor and 2,1,3-benzothiadiazole as acceptor, the corresponding two-branch dimer and three- branch trimer, have been investigated by means of steady-state and femtosecond time- resolved stimulated emission fluorescence depletion (FS TR-SEP FD) techniques in different polar solvents. The TD-DFT calculations are further performed to explain the observed ICT properties. The interpretation of the experimental results is based on the comparative studies of the series of compounds which have increased amount of identical branch moiety. The similarity of the absorption and fluorescence spectra as well as strong solvent-dependence of the spectral properties for the three compounds reveal that the excited state of the dimer and trimer are nearly the same with that of the monomer, which may localize on one branch. It is found that polar excited state emerged through multidimensional intramolecular charge transfer from the donating moiety to the acceptor upon excitation, and quickly relaxed to one branch before emission. Even so, the red-shift in the absorption and emission spectra and decreased fluorescence radiative lifetime with respect to their monomer counterpart still suggest some extent delocalization of excited state in the dimer and trimer upon excitation. The similar behavior of their excited ICT state is demonstrated by FS TR-SEP FD measurements, and shows that the trimer has the largest charge-separate extent in all studied three samples. Finally, steady-state excitation anisotropy measurements has further been carried out to estimate the nature of the optical excitation and the mechanism of energy redistribution among the branches, where no plateau through the ICT band suggests the intramolecular excitation transfer process between the branches in dimer and trimer. 展开更多
关键词 branched intramolecular charge transfer molecule Fluorescence decay Femtosecond time-resolved stimulated emission fluorescence depletion Steady-state excitationanisotropy
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Yield, Leaf Senescence, and Cry1Ac Expression in Response to Removal of Early Fruiting Branches in Transgenic Bt Cotton 被引量:1
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作者 DONG He-zhong TANG Wei LI Wei-jiang LI Zhen-huai NIU Yue-hua ZHANG Dong-mei 《Agricultural Sciences in China》 CAS CSCD 2008年第6期692-702,共11页
Two-year field experiments were conducted at Linqing, Yellow River valley of China, to study the plant response to the removal of early fruiting branches in transgenic Bt (Bacillus thuringiensis) cotton (Gossypium ... Two-year field experiments were conducted at Linqing, Yellow River valley of China, to study the plant response to the removal of early fruiting branches in transgenic Bt (Bacillus thuringiensis) cotton (Gossypium hirsutum L.) from 2003 to 2004. Plants were undamaged and treated by removing two basal fruiting branches (FB) at squaring to form the control and the removal treatment, respectively. The plant height, leaf area (LA), dry weight of fruiting forms (DWFF), the number of fruiting nodes (NFN), photosynthetic (Pn) rate, and levels of leaf chlorophyll (Chl), N, P, K, and Cry lAc protein in main- stem leaves were measured at a 10- or 20-d interval after FB removal, and the sink/source ratio as indicated by NFN/LA and DWFF/LA was determined. FB removal significantly increased the plant height, LA, and plant biomass in both years. Lint yields were increased 7.5 and 5.2% by removal compared with their controls in 2003 and 2004, respectively. Significant increases in boll size (5.7 and 5.1%) were also observed in removal than in control for both years. Either NFN/LA or DWFF/LA was significantly reduced by removal before 40 d after removal; however, both NFN/LA and DWFF/LA were significantly enhanced by FB removal at 80 d after removal compared to the untreated control. There was no significant difference in fiber quality in the first two harvests between removal and control, but fiber strength and micronarie in the third harvest were significantly improved by FB removal. In terms of leaf Chl, Pn rate, levels of total N, P, and K in late season, leaf senescence was considerably delayed by FB removal. Levels of CrylAc protein in the fully expanded young leaves were considerably higher in FB-excised plants than in control, indicating FB removal enhanced CrylAc expression. It is suggested that the yield and quality improvement with FB removal may be attributed to the increased NFN/LA or DWFF/LA in late season and delayed leaf senescence, respectively. FB removal can be a potential practice incorporated into the intensive cultivation system for enhancing transgenic Bt cotton production. 展开更多
关键词 branch removal Bt cotton Cry lAc protein leaf senescence photosynthetic rate sink/source ratio
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Dual-Branch Multi-Level Feature Aggregation Network for Pansharpening 被引量:1
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作者 Gui Cheng Zhenfeng Shao +2 位作者 Jiaming Wang Xiao Huang Chaoya Dang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第11期2023-2026,共4页
Dear Editor,In pansharpening task,the most existing deep-learning-based pansharpening methods fail to fully utilize the different level features,inevitably leading to spectral or spatial distortions.To address this ch... Dear Editor,In pansharpening task,the most existing deep-learning-based pansharpening methods fail to fully utilize the different level features,inevitably leading to spectral or spatial distortions.To address this challenge,in this letter,we propose a dual-branch multi-level feature aggregation network for pansharpening(DMFANet). 展开更多
关键词 DUAL utilize branch
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GENERATOR VIBRATION FAULT DIAGNOSIS METHOD BASED ON ROTOR VIBRATION AND STATOR WINDING PARALLEL BRANCHES CIRCULATING CURRENT CHARACTERISTICS 被引量:2
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作者 Wan Shuting Li Heming +1 位作者 Li Yonggang Tang Guiji 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期592-596,共5页
Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or... Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or imbalance fault, and the vibration of the second frequency will increase when the air-gap static eccentricity fault occurs. Next, the characteristics of the stator winding parallel branches circulating current are analyzed, which are that the second harmonics circulating current will increase when the rotor winding inter-turn short circuit fault occurs, and the fundamental circulating current will increase when the air-gap eccentricity fault occurs, neither being strongly affected by the imbalance fault. Considering the differences of the rotor vibration and circulating current characteristics caused by different rotor faults, a method of generator vibration fault diagnosis, based on rotor vibration and circulating current characteristics, is developed. Finally, the rotor vibration and circulating current of a type SDF-9 generator is measured in the laboratory to verify the theoretical analysis presented above. 展开更多
关键词 Generator Fault diagnosis Rotor vibration characteristic Stator winding parallel branches circulating current
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