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Lightweight Res-Connection Multi-Branch Network for Highly Accurate Crowd Counting and Localization
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作者 Mingze Li Diwen Zheng Shuhua Lu 《Computers, Materials & Continua》 SCIE EI 2024年第5期2105-2122,共18页
Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep learning.However,there have been stillmany challenges i... Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep learning.However,there have been stillmany challenges including crowd multi-scale variations and high network complexity,etc.To tackle these issues,a lightweight Resconnection multi-branch network(LRMBNet)for highly accurate crowd counting and localization is proposed.Specifically,using improved ShuffleNet V2 as the backbone,a lightweight shallow extractor has been designed by employing the channel compression mechanism to reduce enormously the number of network parameters.A light multi-branch structure with different expansion rate convolutions is demonstrated to extract multi-scale features and enlarged receptive fields,where the information transmission and fusion of diverse scale features is enhanced via residual concatenation.In addition,a compound loss function is introduced for training themethod to improve global context information correlation.The proposed method is evaluated on the SHHA,SHHB,UCF-QNRF and UCF_CC_50 public datasets.The accuracy is better than those of many advanced approaches,while the number of parameters is smaller.The experimental results show that the proposed method achieves a good tradeoff between the complexity and accuracy of crowd counting,indicating a lightweight and high-precision method for crowd counting. 展开更多
关键词 Crowd counting Res-connection multi-branch compound loss function
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Multi-Branch Fault Line Location Method Based on Time Difference Matrix Fitting
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作者 Hua Leng Silin He +3 位作者 Jian Qiu Feng Liu Xinfei Huang Jiran Zhu 《Energy Engineering》 EI 2024年第1期77-94,共18页
The distribution network exhibits complex structural characteristics,which makes fault localization a challenging task.Especially when a branch of the multi-branch distribution network fails,the traditional multi-bran... The distribution network exhibits complex structural characteristics,which makes fault localization a challenging task.Especially when a branch of the multi-branch distribution network fails,the traditional multi-branch fault location algorithm makes it difficult to meet the demands of high-precision fault localization in the multi-branch distribution network system.In this paper,the multi-branch mainline is decomposed into single branch lines,transforming the complex multi-branch fault location problem into a double-ended fault location problem.Based on the different transmission characteristics of the fault-traveling wave in fault lines and non-fault lines,the endpoint reference time difference matrix S and the fault time difference matrix G were established.The time variation rule of the fault-traveling wave arriving at each endpoint before and after a fault was comprehensively utilized.To realize the fault segment location,the least square method was introduced.It was used to find the first-order fitting relation that satisfies the matching relationship between the corresponding row vector and the first-order function in the two matrices,to realize the fault segment location.Then,the time difference matrix is used to determine the traveling wave velocity,which,combined with the double-ended traveling wave location,enables accurate fault location. 展开更多
关键词 multi-branch lines distribution network fault location double-ended traveling wave positioning least square method
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Fatigue Behavior of Open-Holed CFRP Laminates with Initially Cut Fibers
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作者 Sudarsono Sudarsono Keiji Ogi 《Open Journal of Composite Materials》 2017年第1期49-62,共14页
Carbon fiber-reinforced plastic (CFRP) laminates with initially cut fibers (ICFs) have good formability without large degradation of static strength;however, their fatigue behavior has not been investigated thus far. ... Carbon fiber-reinforced plastic (CFRP) laminates with initially cut fibers (ICFs) have good formability without large degradation of static strength;however, their fatigue behavior has not been investigated thus far. In this paper, we investigated fatigue behavior and damage progress of open-holed CFRP laminates with ICFs having interlayers. Three types of CFRP laminates were employed: a laminate without ICF fabricated using an autoclave (Continuous-A), a laminate with ICF fabricated using an autoclave (ICF-A) and a laminate with ICF fabricated using press molding (ICF-P). First, fatigue test was conducted to obtain S (maximum stress)-N (the number of cycles to failure) curves in order to reveal fatigue strength. The fatigue tests for several specimens were interrupted at three prescribed numbers of cycles to observe damage progress. It is found that the Continuous-A laminate shows little strength degradation in the S-N curve while fatigue strength in both ICF laminates is decreased by approximately 30% at N of 106. In contrast, the damage progress of the ICF-P laminate is the least among the three laminates while the delamination progress at both edges and around the hole in the Continuous-A laminate is the most prominent. 展开更多
关键词 Carbon Fiber-Reinforced Plastic FATIGUE Initially CUT Fibers open-holed INTERLAYER
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Multi-Branch Deepfake Detection Algorithm Based on Fine-Grained Features
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作者 Wenkai Qin Tianliang Lu +2 位作者 Lu Zhang Shufan Peng Da Wan 《Computers, Materials & Continua》 SCIE EI 2023年第10期467-490,共24页
With the rapid development of deepfake technology,the authenticity of various types of fake synthetic content is increasing rapidly,which brings potential security threats to people’s daily life and social stability.... With the rapid development of deepfake technology,the authenticity of various types of fake synthetic content is increasing rapidly,which brings potential security threats to people’s daily life and social stability.Currently,most algorithms define deepfake detection as a binary classification problem,i.e.,global features are first extracted using a backbone network and then fed into a binary classifier to discriminate true or false.However,the differences between real and fake samples are often subtle and local,and such global feature-based detection algorithms are not optimal in efficiency and accuracy.To this end,to enhance the extraction of forgery details in deep forgery samples,we propose a multi-branch deepfake detection algorithm based on fine-grained features from the perspective of fine-grained classification.First,to address the critical problem in locating discriminative feature regions in fine-grained classification tasks,we investigate a method for locating multiple different discriminative regions and design a lightweight feature localization module to obtain crucial feature representations by augmenting the most significant parts of the feature map.Second,using information complementation,we introduce a correlation-guided fusion module to enhance the discriminative feature information of different branches.Finally,we use the global attention module in the multi-branch model to improve the cross-dimensional interaction of spatial domain and channel domain information and increase the weights of crucial feature regions and feature channels.We conduct sufficient ablation experiments and comparative experiments.The experimental results show that the algorithm outperforms the detection accuracy and effectiveness on the FaceForensics++and Celeb-DF-v2 datasets compared with the representative detection algorithms in recent years,which can achieve better detection results. 展开更多
关键词 Deepfake detection fine-grained classification multi-branch global attention
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Wireless Interference Classification with Low Complexity Multi-Branch Networks
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作者 Song Ma Yufan Cheng +3 位作者 Ying Mou Pengyu Wang Qihang Peng Jun Wang 《China Communications》 SCIE CSCD 2023年第4期382-394,共13页
In non-cooperative communication systems,wireless interference classification(WIC)is one of the most essential technologies.Recently,deep learning(DL)based WIC methods have been proposed.However,conventional DL-based ... In non-cooperative communication systems,wireless interference classification(WIC)is one of the most essential technologies.Recently,deep learning(DL)based WIC methods have been proposed.However,conventional DL-based WIC methods have high computational complexity and unsatisfactory accuracy,especially when the interference-tonoise ratio(INR)is low.To this end,we propose three effective approaches.Firstly,we introduce multibranch convolutional neural networks(CNNs)for interference recognition.The multi-branch CNN is constructed by repeating a layer that aggregates several transformations with the same topology,and it notably improves the recognition ability for WIC.Our design avoids the carefully crafted selection of each transformation.Unfortunately,multi-branch CNNs are computationally expensive and memory-inefficient.To this end,we further propose Low complexity multibranch networks(LCMN),which are mathematically equivalent to multi-branch CNNs but maintain low computing costs and efficient inference.Thirdly,we present novel loss function,which encourages networks to have consistent prediction probabilities for samples with high visual similarities,resulting in increasing recognition accuracy of LCMN.Experimental results demonstrate the proposed methods consistently boost the classification performance of WIC without substantially increasing computational overhead compared to traditional DL-based methods. 展开更多
关键词 electromagnetic interference wireless interference identification deep learning multi-branch architectures
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Proppant transport law in multi-branched fractures induced by volume fracturing
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作者 GUO Tiankui LYU Mingkun +6 位作者 CHEN Ming XU Yun WENG Dingwei QU Zhanqing DAI Caili HOU Jian LIU Xiaoqiang 《Petroleum Exploration and Development》 SCIE 2023年第4期955-970,共16页
To further clarify the proppant transport and placement law in multi-branched fractures induced by volume fracturing, proppant transport simulation experiments were performed with different fracture shapes, sand ratio... To further clarify the proppant transport and placement law in multi-branched fractures induced by volume fracturing, proppant transport simulation experiments were performed with different fracture shapes, sand ratios, branched fracture opening time and injection sequence of proppants in varied particle sizes. The results show that the settled proppant height increases and the placement length decreases in main fractures as the fracturing fluid diverts gradually to the branched fractures at different positions. The flow rate in branched fractures is the main factor affecting their filling. The diverion to branched fractures leads to low flow rate and poor filling of far-wellbore branched fractures. The inclined fracture wall exerts a frictional force on the proppant to slow its settlement, thus enhancing the vertical proppant distribution in the fracture. The increase of sand ratio can improve the filling of near-wellbore main fracture and far-wellbore branched fracture and also increase the settled proppant height in main fracture. Due to the limitation of fracture height, when the sand ratio increases to a certain level, the increment of fracture filling decreases. When branched fracture is always open(or extends continuously), the supporting effect on the branched fractures is the best, but the proppant placement length within the main fractures is shorter. The fractures support effect is better when it is first closed and then opened(or extends in late stage) than when it is first opened and then closed(or extends in early stage). Injecting proppants with different particle sizes in a specific sequence can improve the placement lengths of main fracture and branched fracture. Injection of proppants in an ascending order of particle size improves the near-wellbore fracture filling, to a better extent than that in a descending order of particle size. 展开更多
关键词 volume fracturing proppant transport complex fracture support multi-branched fracture fracture inclination opening time of branched fracture
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Parameters Optimization of Multi-Branch Horizontal Well Basing on Streamline Simulation 被引量:1
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作者 Hong-Jun Yin Xiao-Qi Chen +1 位作者 Ming Cai Jun-Ting Zhang 《Engineering(科研)》 2010年第12期953-957,共5页
As a highly efficient production method, the technique of multi-branch horizontal well is widely used in low permeability reservoirs, heavy oil reservoirs, shallow layer reservoirs and multi-layer reservoirs, because ... As a highly efficient production method, the technique of multi-branch horizontal well is widely used in low permeability reservoirs, heavy oil reservoirs, shallow layer reservoirs and multi-layer reservoirs, because it can significantly improve the productivity of a single well, inhibit coning and enhance oil recovery. Study on sweep efficiency and parameters optimization of multi-branch horizontal well is at the leading edge of research. Therefore, the study is important for enhancing oil recovery and integral exploitation benefit of oil fields. In many applications, streamline simulation shows particular advantages over finite-difference simulation. With the advantages of streamline simulation such as its ability to display paths of fluid flow and acceleration factor in simulation, the flooding process is more visual. The communication between wells and flooding area has been represented appropriately. This method has been applied to the XS9 reservoir in Daqing Oilfield. The production history of this reservoir is about 10 years. The reservoir is maintained above bubble point so that the simulation meets the slight compressibility assumption. New horizontal wells are drilled following this rule. 展开更多
关键词 STREAMLINE Simulation multi-branch HORIZONTAL WELL Optimization Waterflood SWEEP EFFICIENCY
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Optimization for Hydroforming Loading Paths of Parallel Multi-branch Tubes Based on Grey System Theory
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作者 Kai Zhang Xiao-Ting Xiao +2 位作者 Zhen Chen Hua-Dian Wen Ying Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第4期116-120,共5页
According to characteristic of hydroforming of parallel multi-branch tubes,multi-objective problems were transformed to single objective problem of relational grade comparison by grey system theory.Two different objec... According to characteristic of hydroforming of parallel multi-branch tubes,multi-objective problems were transformed to single objective problem of relational grade comparison by grey system theory.Two different objectives were selected,according to the principle that process parameters were optimal which of grey relational grade were maximum,the optimal loading parameters under different objective condition were obtained,and loading paths were optimized.The results indicated that parallel multi-branch tubes hydroformed under loading paths optimized by grey system theory could meet with the requirement that objective was optimal.And the optimal loading paths under different objectives were different,and the appropriate objective should be selected according to forming characteristic. 展开更多
关键词 relational grade parallel multi-branch tubes HYDROFORMING OPTIMIZATION
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基于改进YOLOX算法的交通标志检测研究
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作者 王惠吾 洪智勇 +2 位作者 王宪伟 余文华 李泽亮 《五邑大学学报(自然科学版)》 CAS 2023年第3期73-78,共6页
为进一步提升交通标志图像视觉检测算法的性能,本文提出了一种改进的YOLOX_M算法.首先为YOLOX_M构建了新的特征融合网络Multi-branch FPN,该网络通过多分支结构提取模型底层的特征信息,并通过FPN进行特征融合,可进一步提高模型利用特征... 为进一步提升交通标志图像视觉检测算法的性能,本文提出了一种改进的YOLOX_M算法.首先为YOLOX_M构建了新的特征融合网络Multi-branch FPN,该网络通过多分支结构提取模型底层的特征信息,并通过FPN进行特征融合,可进一步提高模型利用特征的能力.其次,在YOLOX_M检测头引入的Alpha-GIoU损失函数,可以更好地应用于带噪声的边界框,提高边界框的回归精度.实验表明,改进后的YOLOX_M模型在数据集TT100K上的mAP提高了1.8%,具备较好的检测性能.本文研究结果对交通标志检测具有一定的参考价值. 展开更多
关键词 交通标志检测 特征融合 YOLOX multi-branch FPN Alpha-GIoU
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裸眼多分支水平井开发特征及主控因素 被引量:9
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作者 刘春春 贾慧敏 +4 位作者 毛生发 崔新瑞 彭鹤 李学博 张光波 《煤田地质与勘探》 CAS CSCD 北大核心 2018年第5期140-145,共6页
沁水盆地南部樊庄–郑庄区块裸眼多分支水平井总体开发效果不理想,低产井比例高、单井产量差异大,亟需查明主因,提高开发成效。基于研究区内十余年的开发实践,利用统计分析、回归分析等手段将产气特征归纳为持续高产、先高后低、持续低... 沁水盆地南部樊庄–郑庄区块裸眼多分支水平井总体开发效果不理想,低产井比例高、单井产量差异大,亟需查明主因,提高开发成效。基于研究区内十余年的开发实践,利用统计分析、回归分析等手段将产气特征归纳为持续高产、先高后低、持续低产3种类型。研究表明,含气量、渗透率、微幅构造、煤体结构是裸眼多分支水平井能否高产且持续稳产的关键地质因素,在同等富集条件下,渗透率大小是裸眼多分支水平井能否高产的关键;微幅构造与煤体结构决定了高产后能否持续稳产。低含气量、低渗透率、钻进过程分支垮塌、钻井液污染储层是持续低产井低产的主因。研究结果指导了裸眼多分支水平井工艺技术优化,大幅提高了单井产气量。 展开更多
关键词 裸眼多分支 水平井 开发特征 渗透率 微幅构造 煤体结构
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Productivity model for gas reservoirs with open-hole multi-fracturing horizontal wells and optimization of hydraulic fracture parameters 被引量:3
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作者 Jianqiang Xue Nianyin Li +2 位作者 Xiaobing Lu Suiwang Zhang Yong Wang 《Petroleum》 2017年第4期454-460,共7页
Multi-fractured horizontal wells are commonly employed to improve the productivity of low and ultra-low permeability gas reservoirs.However,conventional productivity models for open-hole multi-fractured horizontal wel... Multi-fractured horizontal wells are commonly employed to improve the productivity of low and ultra-low permeability gas reservoirs.However,conventional productivity models for open-hole multi-fractured horizontal wells do not consider the interferences between hydraulic fractures and the open-hole segments,resulting in significant errors in calculation results.In this article,a novel productivity prediction model for gas reservoirs with open-hole multi-fractured horizontal wells was proposed based on complex potential theories,potential superimposition,and numerical analysis.Herein,an open-hole segment between two adjacent fractures was regarded as an equivalent fracture,which was discretized as in cases of artificial fractures.The proposed model was then applied to investigate the effects of various parameters,such as the angle between the fracture and horizontal shaft,fracture quantity,fracture length,diversion capacity of fractures,horizontal well length,and inter-fracture distance,on the productivity of low permeability gas reservoirs with multi-fractured horizontal wells.Simulation results revealed that the quantity,length,and distribution of fractures had significant effects on the productivity of low permeability gas reservoirs while the effects of the diversion capacity of fractures and the angle between the fracture and horizontal shaft were negligible.Additionally,a U-shaped distribution of fracture lengths was preferential as the quantity of fractures at shaft ends was twice that in the middle area. 展开更多
关键词 Low permeability gas reservoir Multi-fractured horizontal well Productivity prediction open-hole completion Unsteady-state flow Fracture parameters optimization
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Experimental Investigation of Local Scour Around Artificial Reefs in Steady Currents
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作者 TANG Yanli WEI Shuangwu +2 位作者 YANG Mingda WANG Xinxin ZHAO Fenfang 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第2期445-456,共12页
Artificial reef is a man-made object that is deployed purposefully on the seafloor to restore the offshore fishery resources and the ecological environment.To secure its ecological effects,it is important to study the... Artificial reef is a man-made object that is deployed purposefully on the seafloor to restore the offshore fishery resources and the ecological environment.To secure its ecological effects,it is important to study the possible instability of artificial reefs,like drifting and reversing caused by burial and scour in different seafloor conditions.In the present study,experiments of local scour around an artificial reef are carried out in steady currents.The effect of the open-area ratios and the open-hole heights of the cubic reefs,and the bottom angles of the triangular reefs on the time-scale of the scour process and the equilibrium scour depth are investigated.The results indicate that for the cubic artificial reef,the scour depth decreases with the increasing open-area ratios,and increases with the increasing open-hole heights.In the present study,the optimal prototype of the cubic reef with an open-area ratio of 0.49 and open-height of 0.7 m produces the minimum scour depth.For the triangular reef,the scour depth increases when the bottom angle increases.Moreover,based on the experimental results,empirical equations of the effects of the cut-opening and the bottom angle on the maximum equilibrium scour depth are proposed.The formulas will provide theoretical support and practical guidance for the optimized design and construction of artificial reefs. 展开更多
关键词 local scour artificial reefs open-area ratios open-hole heights bottom angles
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Comparison of Some Features of the Subtropical Countercurrent, the North Equatorial Current and the North Equatorial Countercurrent in the Northwest Pacific Ocean
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作者 Sun Xiangping(First Institute of Oceanography, SOA, Qingdao) 《Marine Science Bulletin》 CAS 1999年第2期45-58,共14页
Based on the data of temperature and salinity of the 137°E section in the winters and summers from 1967 to 1995, the geo-strophic current of the section is calculated and analyzed, and the drifting tracks of the ... Based on the data of temperature and salinity of the 137°E section in the winters and summers from 1967 to 1995, the geo-strophic current of the section is calculated and analyzed, and the drifting tracks of the satellite tracking drift buoy distributed on the 144°E section are also analyzed. In light of the surface dynamic height distribution in the CSK atlas, this paper compares some features of the Subtropical Countercurrent, the North Equatorial Current and the North Equatorial Countercurrent. The main results are as follows:1. The Subtropical Countercurrent, the North Equatorial Current and the North Equatorial Countercurrent are not simple single currents, but have two branches or more. One of the common features of the three currents mentioned above is "multi-branching" of the current.2. The zonal distribution of the flow velocity structure, the alternate and intermittent occurrence of the eastward and westward flows, with a shallower flow layer and belonging to the surface flow or subsurface 展开更多
关键词 the SUBTROPICAL Countercurrent the NORTH EQUATORIAL Current the NORTH EQUATORIAL Countercurrent multi-branching ZONAL structure
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Airflow distribution law of multi-branch pipe of pneumatic rice direct seeder based on dimensional analysis
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作者 Wei Qin Zaiman Wang +5 位作者 Minghua Zhang Siyu He Xuguo Wang Youcong Jiang Zishun Huang Ying Zang 《International Journal of Agricultural and Biological Engineering》 SCIE CAS 2023年第1期111-127,共17页
In order to investigate the flow characteristics and distribution law of airflow in multi-branch pipe of pneumatic rice precision direct seeder and obtain the mathematical model between airflow parameters and pipe geo... In order to investigate the flow characteristics and distribution law of airflow in multi-branch pipe of pneumatic rice precision direct seeder and obtain the mathematical model between airflow parameters and pipe geometry structure.In this study,the airflow flow law of the multi-branch pipeline of the pneumatic system was studied,the mechanism of airflow flow in the multi-branch pipe was analyzed,and it was clarified that the main factors affecting the airflow flow in the pipe,namely,air density,air dynamic viscosity,the total flow rate of the inlet branch pipe,the length of the closed end of the header,the inner diameter of the outlet branch pipe,and the outlet branch pipe spacing.Numerical simulations were carried out using Fluent simulation software to elucidate the cause of multi-branch pipes of uneven distribution of airflow in multi-branch pipes,the empirical equation among these factors and the flow velocity of the outlet branch pipe are established by dimensional analysis method.The bench test results show that the established empirical equations are applicable in the following ranges:0.018 m3/s≤Q≤0.054 m3/s,0.045 m≤d≤0.05 m,0.075 m≤L≤0.125 m,0.7 m≤Y 1≤0.875 m(0.5 m≤Y 2≤0.75 m,0.36 m≤Y 3≤0.45 m),the prediction accuracy can be controlled within 10%of the empirical formula,which can provide a reference for the prediction and optimization design of outlet velocity of the multi-branch pipe. 展开更多
关键词 pneumatic system multi-branch pipe axial momentum conservation FLUENT dimensional analysis
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Facile Synthesis of Multi-Branched Gold Nanostructures through a TBAB-Assisted Route in Aqueous Solution and Their SERS Property 被引量:1
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作者 Wang, Luyan Wu, Xinzhou +3 位作者 Pei, Meishan Wu, Zhiyan Li, Xiaonan Tao, Xutang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第1期185-190,共6页
Facile synthesis of multi-branched gold nanostructures by using the tetrabutyl ammonium bromide (TBAB) as a capping agent is described. The reaction is carried out in a one-step process at mild temperature. Gold nan... Facile synthesis of multi-branched gold nanostructures by using the tetrabutyl ammonium bromide (TBAB) as a capping agent is described. The reaction is carried out in a one-step process at mild temperature. Gold nanostructures with more than six sharp branches ranging from 70 to 130 nm in length are synthesized in high yield. It is proposed that the relative weak adsorption capacity of TBAB leads to the incompletely covered gold surface and the growth of nanoparticles occurs on the uncovered gold surface, and therefore short branches appear consequently. Then positively charged TBAB layers on the gold surfaces prevent the branches from aggregating with each other which stimulates the branch growth. The prepared branched gold nanoparticles show efficient surface-enhanced Raman scattering (SERS) properties. Low temperature (4 ℃) is unfavorable to the formation of multi-branched gold nanostructures, and only thin small irregular plate-like nanoparticles are produced. The addition of SDS in TBAB aqueous solution results in forming SDS micelles at much lower concentration of SDS (0.4 mmol/L) as compared to that in pure water, and short branched gold nanoparticles are obtained in the SDS-TBAB system. 展开更多
关键词 gold multi-branched nanostructures tetrabutyl ammonium bromide surface-enhanced Ramanscattering
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Effects of the structure of the branches on the two-photon absorption properties for the multi-branched molecules with nitrogen (N) as coupling center
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作者 SUN XueQin ZHAO Xian +2 位作者 ZHOU ShuLan LI BaiDong CHENG XiuFeng 《Science China Chemistry》 SCIE EI CAS 2008年第1期92-96,共5页
In order to investigate the effects of the structure of branches on the TPA properties for multi-branched molecules, the TPA cross section is calculated by using ZINDO/SOS method. The investigated mole- cules have dif... In order to investigate the effects of the structure of branches on the TPA properties for multi-branched molecules, the TPA cross section is calculated by using ZINDO/SOS method. The investigated mole- cules have different branches (chomorfores based on stilbene, dithienothiophene and flourene) with nitrogen(N) as coupling center. The results show that the cooperative enhancement in multi-branched molecules depends on the structures of the branches and the structures of branches play an important role in the enhancement of the TPA cross section. The designed molecules with stilbene and dithie- nothiophene as branched possess relatively larger two-photon absorption cross sections. 展开更多
关键词 STRUCTURE of BRANCHES TPA properties ZINDO/SOS multi-branched MOLECULES
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Thermodynamic Transitions of Antiferromagnetic Ising Model on the Fractional Multi-branched Husimi Recursive Lattice
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作者 黄然 陈翀 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第11期749-754,共6页
The multi-branched Husimi recursive lattice is extended to a virtual structure with fractional numbers of branches joined on one site. Although the lattice is undrawable in real space, the concept is consistent with r... The multi-branched Husimi recursive lattice is extended to a virtual structure with fractional numbers of branches joined on one site. Although the lattice is undrawable in real space, the concept is consistent with regular Husimi lattice. The Ising spins of antiferromagnetic interaction on such a set of lattices are calculated to check the critical temperatures(Tc) and ideal glass transition temperatures(Tk) variation with fractional branch numbers. Besides the similar results of two solutions representing the stable state(crystal) and metastable state(supercooled liquid)and indicating the phase transition temperatures, the phase transitions show a well-defined shift with branch number variation. Therefore the fractional branch number as a parameter can be used as an adjusting tool in constructing a recursive lattice model to describe real systems. 展开更多
关键词 critical temperature ideal glass transition Ising model FRACTIONAL multi-branched Husimi LATTICE
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STRNet:Triple-stream Spatiotemporal Relation Network for Action Recognition 被引量:2
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作者 Zhi-Wei Xu Xiao-Jun Wu Josef Kittler 《International Journal of Automation and computing》 EI CSCD 2021年第5期718-730,共13页
Learning comprehensive spatiotemporal features is crucial for human action recognition. Existing methods tend to model the spatiotemporal feature blocks in an integrate-separate-integrate form, such as appearance-and-... Learning comprehensive spatiotemporal features is crucial for human action recognition. Existing methods tend to model the spatiotemporal feature blocks in an integrate-separate-integrate form, such as appearance-and-relation network(ARTNet) and spatiotemporal and motion network(STM). However, with blocks stacking up, the rear part of the network has poor interpretability. To avoid this problem, we propose a novel architecture called spatial temporal relation network(STRNet), which can learn explicit information of appearance, motion and especially the temporal relation information. Specifically, our STRNet is constructed by three branches,which separates the features into 1) appearance pathway, to obtain spatial semantics, 2) motion pathway, to reinforce the spatiotemporal feature representation, and 3) relation pathway, to focus on capturing temporal relation details of successive frames and to explore long-term representation dependency. In addition, our STRNet does not just simply merge the multi-branch information, but we apply a flexible and effective strategy to fuse the complementary information from multiple pathways. We evaluate our network on four major action recognition benchmarks: Kinetics-400, UCF-101, HMDB-51, and Something-Something v1, demonstrating that the performance of our STRNet achieves the state-of-the-art result on the UCF-101 and HMDB-51 datasets, as well as a comparable accuracy with the state-of-the-art method on Something-Something v1 and Kinetics-400. 展开更多
关键词 Action recognition spatiotemporal relation multi-branch fusion long-term representation video classification
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A new stress-based multi-scale failure criterion of composites and its validation in open hole tension tests 被引量:4
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作者 Li Xing Guan Zhidong +1 位作者 Li Zengshan Liu Lu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1430-1441,共12页
A new stress-based multi-scale failure criterion is proposed based on a series of off-axis tension tests, and their corresponding fiber failure modes and matrix failure modes are determined at the microscopic level. I... A new stress-based multi-scale failure criterion is proposed based on a series of off-axis tension tests, and their corresponding fiber failure modes and matrix failure modes are determined at the microscopic level. It is a physical mechanism based, three-dimensional damage analysis criterion which takes into consideration the constituent properties on the macroscopic failure behavior of the composite laminates. A complete set of stress transformation, damage determination and evolution methods are established to realize the application of the multi-scale method in failure analysis. Open-hole tension(OHT) specimens of three material systems(CCF300/5228, CCF300/5428 and T700/5428) are tested according to ASTM standard D5766, and good agreements are found between the experimental results and the numerical predictions. It is found that fiber strength is a key factor influencing the ultimate strength of the laminates, while matrix failure alleviates the stress concentration around the hole. Different matchings of fiber and matrix result in different failure modes as well as ultimate strengths. 展开更多
关键词 Composite material Failure criterion Multi-scale Off-axis tension open-hole tension
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