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Crowdedness estimation approach based on stereovision for bus passengers
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作者 朱秋煜 江毅凭 +1 位作者 邓伟俊 唐利 《Journal of Shanghai University(English Edition)》 2010年第1期17-23,共7页
An estimation approach is proposed in this paper based on the binocular stereovision to collect the degree of crowdedness in public transports. The proposed method combines the disparity with frame differences to extr... An estimation approach is proposed in this paper based on the binocular stereovision to collect the degree of crowdedness in public transports. The proposed method combines the disparity with frame differences to extract the foreground object. An adaptive window normalized cross correlation (NCC) matching and interpolated method is applied to get the sub-pixel image disparity value. Then, the foreground object is projected to the horizontal plane to eliminate the influence of the occlusion and perspective effect. Finally the degree of crowdedness is calculated from the area and the perimeter of the foreground objects. Experimental results show that the proposed method can obtain good estimation results in the simulated scenes in the laboratory and on parking or moving buses. This approach is effective to illumination changes, shadows and occlusion of passengers. 展开更多
关键词 PASSENGER degree of crowdedness binocular stereovision DISPARITY foreground object detection
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Crowdedness imposes stress on tumor metastasis in Drosophila melanogaster
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作者 Wenzhe Li Zhiyuan Zhang +4 位作者 Lealia Li Xiong Huiyi Yu Jiuhong Huang Ruixiu Cao Lei Xue 《Genes & Diseases》 2025年第5期77-80,共4页
Tumor metastasis is the primary cause of mortality in cancer patients,yet its mechanism remains poorly understood.Among the known cancer-related factors,lifestyle and environmental influences such as tobacco use,diet,... Tumor metastasis is the primary cause of mortality in cancer patients,yet its mechanism remains poorly understood.Among the known cancer-related factors,lifestyle and environmental influences such as tobacco use,diet,and viral infections have been considered“stressors”.Prolonged exposure to these stresses significantly increases the risk of tumor formation.Yet,the impact of these environmental factors on tumor metastasis remains an intriguing and open question. 展开更多
关键词 stressors environmental factors crowdedness tumor metastasis cancer mortality environmental influences Drosophila melanogaster
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An Unforgettable Bus Trip
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作者 马炳坤 张超(指导) 《中学生英语》 2025年第27期7-7,共1页
This summer holiday,my older brother and I paid a visit to my grandparents by bus.The bus was crowded,but everyone seemed to be friendly and helpful.We enjoyed beautiful views all the way.At first,we saw one hill afte... This summer holiday,my older brother and I paid a visit to my grandparents by bus.The bus was crowded,but everyone seemed to be friendly and helpful.We enjoyed beautiful views all the way.At first,we saw one hill after another. 展开更多
关键词 GRANDPARENTS beautiful views summer holiday bus trip crowded bus hills friendly people
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A Minimalistic and Decentralised Approach to Formation Control for Crowded UUV Swarms Inspired by Fish Schooling
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作者 Xuhang Wu Xiangyang Deng +5 位作者 Bang Wen Shengzhi Yue Siyang Shao Fumin Zhang Fang Wang Yuanshan Lin 《Journal of Bionic Engineering》 2025年第5期2646-2659,共14页
Formation control remains a critical challenge in cooperative multi-agent systems,particularly for Unmanned Underwater Vehicles(UUVs).Conventional approaches often suffer from several limitations,including reliance on... Formation control remains a critical challenge in cooperative multi-agent systems,particularly for Unmanned Underwater Vehicles(UUVs).Conventional approaches often suffer from several limitations,including reliance on global information,limited adaptability,high computational complexity,and poor scalability.To address these issues,we propose a novel bio-inspired formation control method for UUV swarms,drawing inspiration from the self-organizing behavior of fish schools.Our method integrates three key components:(1)a coordinated motion strategy without predefined targets that enables individual UUVs to align their movements via simple left or right rotations based solely on local neighbor interactions;(2)a target-directed movement strategy that guides UUVs toward specified regions;and(3)a dispersion control strategy that prevents overcrowding by regulating local spatial distributions.Simulation results confirm that the method achieves robust formation control and efficient area coverage using only local perception.Validation in a 9-UUV simulation environment demonstrates the approach’s flexibility,decentralization,and computational efficiency,making it particularly suitable for large-scale swarms with limited sensing and processing capabilities. 展开更多
关键词 Formation control Bio-inspired formation control Crowded UUV swarm Multi-robot systems
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Identification method of crowded passenger flow based on automatic fare collection data of Nanjing Metro 被引量:3
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作者 Lu Jia Ren Gang Xu Linghui 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期236-241,共6页
To relieve traffic congestion in urban rail transit stations,a new identification method of crowded passenger flow based on automatic fare collection data is proposed.First,passenger travel characteristics are analyze... To relieve traffic congestion in urban rail transit stations,a new identification method of crowded passenger flow based on automatic fare collection data is proposed.First,passenger travel characteristics are analyzed by observing the temporal distribution of inflow passengers each hour and the spatial distribution concerning cross-section passenger flow.Secondly,the identification method of crowded passenger flow is proposed to calculate the threshold via the probability density function fitted by Matlab and classify the early-warning situation based on the threshold obtained.Finally,a case study of Xinjiekou station is conducted to prove the validity and practicability of the proposed method.Compared to the traditional methods,the proposed comprehensive method can remove defects such as efficiency and delay.Furthermore,the proposed method is suitable for other rail transit companies equipped with automatic fare collection systems. 展开更多
关键词 travel characteristic identification method crowded passenger flow automatic fare collection
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Automated evaluation of parapapillary choroidal microvasculature in crowded optic discs:a controlled,optical coherence tomography angiography study 被引量:2
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作者 Hatice Arda Hidayet Sener +5 位作者 Ozge Temizyurek Hatice Kubra Sonmez Duygu Gulmez Sevim Cem Evereklioglu Fatih Horozoglu Ayse Busra Gunay Sener 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期113-118,共6页
AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control... AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control subjects were enrolled in the study.One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm^(2) rectangular area.Radial peripapillary capillary(RPC)density,peripapillary retinal nerve fiber layer(pRNFL)thickness,cup volume,rim area,disc area,cup-to-disc(c/d)area ratio,and vertical c/d ratio were obtained automatically using device software.Automated parapapillary choroidal microvasculature(PPCMv)density was calculated using MATLAB software.When the vertical c/d ratio of the optic disc was absent or small cup,it was considered as a crowded disc.RESULTS:The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes(P=0.740).There was no difference in pRNFL between the two groups(P=0.102).There were no differences in RPC density in whole image(P=0.826)and peripapillary region(P=0.923),but inside disc RPC density was higher in crowded optic discs(P=0.003).The PPCMv density in the inner-hemisuperior region was also lower in crowded discs(P=0.026).The pRNFL thickness was positively correlated with peripapillary RPC density(r=0.498,P<0.001).The inside disc RPC density was negatively correlated with c/d area ratio(r=-0.341,P=0.002).CONCLUSION:The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs. 展开更多
关键词 crowded optic disc ischemic optic neuropathy optical coherence tomography angiography parapapillary choroidal microvasculature
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Analyzing Motion Patterns in Crowded Scenes via Automatic Tracklets Clustering 被引量:1
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作者 王冲 赵旭 +1 位作者 邹毅 刘允才 《China Communications》 SCIE CSCD 2013年第4期144-154,共11页
Crowded scene analysis is currently a hot and challenging topic in computer vision field. The ability to analyze motion patterns from videos is a difficult, but critical part of this problem. In this paper, we propose... Crowded scene analysis is currently a hot and challenging topic in computer vision field. The ability to analyze motion patterns from videos is a difficult, but critical part of this problem. In this paper, we propose a novel approach for the analysis of motion patterns by clustering the tracklets using an unsupervised hierarchical clustering algorithm, where the similarity between tracklets is measured by the Longest Common Subsequences. The tracklets are obtained by tracking dense points under three effective rules, therefore enabling it to capture the motion patterns in crowded scenes. The analysis of motion patterns is implemented in a completely unsupervised way, and the tracklets are clustered automatically through hierarchical clustering algorithm based on a graphic model. To validate the performance of our approach, we conducted experimental evaluations on two datasets. The results reveal the precise distributions of motion patterns in current crowded videos and demonstrate the effectiveness of our approach. 展开更多
关键词 crowded scene analysis motionpattern tracklet automatic clustering
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Abnormal Crowd Behavior Detection Based on the Entropy of Optical Flow 被引量:1
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作者 Zheyi Fan Wei Li +1 位作者 Zhonghang He Zhiwen Liu 《Journal of Beijing Institute of Technology》 EI CAS 2019年第4期756-763,共8页
To improve the detection accuracy and robustness of crowd anomaly detection,especially crowd emergency evacuation detection,the abnormal crowd behavior detection method is proposed.This method is based on the improved... To improve the detection accuracy and robustness of crowd anomaly detection,especially crowd emergency evacuation detection,the abnormal crowd behavior detection method is proposed.This method is based on the improved statistical global optical flow entropy which can better describe the degree of chaos of crowd.First,the optical flow field is extracted from the video sequences and a 2D optical flow histogram is gained.Then,the improved optical flow entropy,combining information theory with statistical physics is calculated from 2D optical flow histograms.Finally,the anomaly can be detected according to the abnormality judgment formula.The experimental results show that the detection accuracy achieved over 95%in three public video datasets,which indicates that the proposed algorithm outperforms other state-of-the-art algorithms. 展开更多
关键词 abnormal events detection optical flows entropy crowded scenes crowd behavior
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Study on Ecological Strategy of Enterprises' Competition 被引量:1
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作者 Xu Fang Li Jianhua +1 位作者 Ly Hong Zhang He 《Ecological Economy》 2005年第3期36-39,共4页
The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to resea... The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to research enterprises' competition problems .explains the ecological characterisiics of enterprises' competition, such as non-symmetry, crowded effect, density effect. competition-rejective effect, suitable resources niche and red queen effect etc., deduces the ecological model of enterprise' competition, and further analyzes enterprises' competition strategy; strategy R and strategy K. on the basis of enterprises' practices, Therefore enterprises' competition ecosystem theories have further been deepened and enriched. 展开更多
关键词 non-symmetry crowded effect competition-rejective effect NICHE ecosystem model ecological strategy
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Toward Optimal Periodic Crowd Tracking via Unmanned Aerial Vehicle
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作者 Khalil Chebil Skander Htiouech Mahdi Khemakhem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期233-263,共31页
Crowd management and analysis(CMA)systems have gained a lot of interest in the vulgarization of unmanned aerial vehicles(UAVs)use.Crowd tracking using UAVs is among the most important services provided by a CMA.In thi... Crowd management and analysis(CMA)systems have gained a lot of interest in the vulgarization of unmanned aerial vehicles(UAVs)use.Crowd tracking using UAVs is among the most important services provided by a CMA.In this paper,we studied the periodic crowd-tracking(PCT)problem.It consists in usingUAVs to follow-up crowds,during the life-cycle of an open crowded area(OCA).Two criteria were considered for this purpose.The first is related to the CMA initial investment,while the second is to guarantee the quality of service(QoS).The existing works focus on very specified assumptions that are highly committed to CMAs applications context.This study outlined a new binary linear programming(BLP)model to optimally solve the PCT motivated by a real-world application study taking into consideration the high level of abstraction.To closely approach different real-world contexts,we carefully defined and investigated a set of parameters related to the OCA characteristics,behaviors,and theCMAinitial infrastructure investment(e.g.,UAVs,charging stations(CSs)).In order to periodically update theUAVs/crowds andUAVs/CSs assignments,the proposed BLP was integrated into a linear algorithm called PCTs solver.Our main objective was to study the PCT problem fromboth theoretical and numerical viewpoints.To prove the PCTs solver effectiveness,we generated a diversified set of PCTs instances with different scenarios for simulation purposes.The empirical results analysis enabled us to validate the BLPmodel and the PCTs solver,and to point out a set of new challenges for future research directions. 展开更多
关键词 Unmanned aerial vehicles periodic crowd-tracking problem open crowded area optimization binary linear programming crowd management and analysis system
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Design and Availability Research of a Flammable and Explosive Volatiles Monitoring and Early Warning System (FEVMEW) for the Bus Crowded Places
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作者 Cen Yu Weibin Guo +2 位作者 Ruyi Li Qiang Chen Tianping Xu 《Journal of Computer and Communications》 2020年第12期83-90,共8页
<div style="text-align:justify;"> In order to reduce the arson or accidental fire losses, we developed a gas sensitive detector used for the rapid detection and early warning of flammables in crowded p... <div style="text-align:justify;"> In order to reduce the arson or accidental fire losses, we developed a gas sensitive detector used for the rapid detection and early warning of flammables in crowded places such as buses. A MEMS (Micro-Electro-Mechanical System) based thin film semiconductor was fabricated as the gas sensor. To obtain the target gas selective response, the surface of the sensitive film was modified with highly active metal catalytic nano-particles. Thus the anti-interference ability was improved and the false alarm rate was effectively reduced. Furthermore, the modular embedded system for information acquisition and transmission was developed. Supported by the Airflow Precision control system (APs), the rapid warning of volatile gas of flammable substances was realized. Experiments showed that RAs has satisfied selectivity to volatiles of usual flammable liquid, such as the output voltage reaches 3 V (0 - 3.3 V). With simulation about the actual installation state in bus, MWs sounds an alarm at 2 minutes after splashing 50 mL 92# petrol to the floor. For the last two years, FEVMEW has been integrated into more than 4000 buses in Hefei. This design has been proved feasible according to the actual operation. </div> 展开更多
关键词 Flammable and Explosive Volatiles Monitoring and Early Warning Bus Crowded Places Gas Sensitive MEMS Chip Airflow Regulating
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The Arabidopsis CROWDED NUCLEI genes regulate seed germination by modulating degradation of ABI5 protein 被引量:5
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作者 Wenming Zhao Chunmei Guan +4 位作者 Jian Feng Yan Liang Ni Zhan Jianru Zuo Bo Ren 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2016年第7期669-678,共10页
In Arabidopsis, the phytohormone abscisic acid (ABA) plays a vital role in inhibiting seed germination and in postgermination seedling establishment. In the ABA signaling pathway, ABI5, a basic Leu zipper transcript... In Arabidopsis, the phytohormone abscisic acid (ABA) plays a vital role in inhibiting seed germination and in postgermination seedling establishment. In the ABA signaling pathway, ABI5, a basic Leu zipper transcription factor, has important functions in the regulation of seed germination. ABI5 protein localizes in nuclear bodies, along with AFP, COP1, and SIZ1, and was degraded through the 26S proteasome pathway. However, the mechanisms of ABI5 nuclear body formation and ABI5 protein degradation remain obscure. In this study, we found that the Arabidopsis CROWDED NUCLEI (CRWN) proteins, predicted nuclear matrix proteins essential for maintenance of nuclear morphology, also participate in ABA-controlled seed germination by regulating the degradation of ABI5 protein. During seed germination, the crwn mutants are hypersensitive to ABA and have higher levels of ABI5 protein compared to wild type. Genetic analysis suggested that CRWNs act upstream of ABIS. The observation that CRWN3 colocalizes with ABI5 in nuclear bodies indicates that CRWNs might participate in ABI5 protein degrada- tion in nuclear bodies. Moreover, we revealed that the extreme C-terminal of CRWN3 protein is necessary for its function in the response to ABA in germination. Our results suggested important roles of CRWNs in ABI5 nuclear body organization and ABI5 protein degradation during seed germination. 展开更多
关键词 ABI5 ARABIDOPSIS CROWDED NUCLEI GERMINATION nuclear body
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Are China's Exports Crowding Out or Being Crowded Out? Evidence from Japan's Imports 被引量:4
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作者 Yan Liu Xunpeng Shi James Laurenceson, 《China & World Economy》 SCIE 2018年第4期1-23,共23页
Previous studies have investigated whether Chinese exports have crowaea oul mose from other countries. However, what has yet to be considered is the evidence based on different quality varieties. Using the most detail... Previous studies have investigated whether Chinese exports have crowaea oul mose from other countries. However, what has yet to be considered is the evidence based on different quality varieties. Using the most detailed Harmonized System 9-digit product- level data, the present paper provides evidence of crowding-out and crowded-out effects across different product quality segments and across manufacturing sectors by quality segments. The empirical evidence presented in this paper shows that the crowding-out effects of Chinese exports have been greatest at the lower end of the quality spectrum but less significant at the higher quality spectrum. Moreover, since 2007, China's own exports of lower quality manufactured goods have been increasingly crowded out. The key policy implication is that China's export path is in line with that taken by other Asian economies in previous decades; the crowded-out effect could achieve win-win outcomes for countries involved; and lower income countries would do well to be open to receive those relocated low value-added industries from China. However, the relocation policy in China is best implemented gradually as climbing up the product quality ladder takes time. 展开更多
关键词 constant market share analysis (CMS) crowded out crowding out industrial relocation
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Fire evacuation visualization in nursing homes based on agent and cellular automata 被引量:3
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作者 Chen Wang Yutong Tang +2 位作者 Mukhtar A.Kassem Heng Li Zhizhan Wu 《Journal of Safety Science and Resilience》 CSCD 2021年第4期181-198,共18页
As China’s population ages and the notion of contemporary people evolves,an increasing number of elderly people opt to spend their final years in a nursing home.Recently,there have been more fires in nursing faciliti... As China’s population ages and the notion of contemporary people evolves,an increasing number of elderly people opt to spend their final years in a nursing home.Recently,there have been more fires in nursing facilities for the elderly.As a result,using computer simulation technology,this paper creates an evacuation micro-simulation model for the elderly and nursing staff,investigates the impact of psychological characteristics and evacuation behavior of the elderly and nursing staffon fire escape during the fire evacuation process,and designs fire evacuation for nursing homes.Based on the nursing home’s regular evacuation paradigm,the study examines the behavioral elements.To simulate the three models and the influence of various behavioral and psychological features on fire evacuation,the authors utilized the MATLAB software,which is based on Agent theory and cellular automata.The simulation results show that the three models proposed in this study are capable of accurately describing reality. 展开更多
关键词 Nursing home Staff evacuation Agent modeling Cellular automata Normal evacuation Crowded evacuation Panic evacuation
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Holiday Reflecti ons Qianjiang Evening News May 5
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《Beijing Review》 2019年第20期10-11,共2页
During this May Day holiday, tourists waiting in endless lines was a common sight at scenic spots, which shows that Chinese people's passion for traveling is continuing to grow. People grasped this opportunity to ... During this May Day holiday, tourists waiting in endless lines was a common sight at scenic spots, which shows that Chinese people's passion for traveling is continuing to grow. People grasped this opportunity to travel, despite knowing that tourist spots and public transportation would be crowded. 展开更多
关键词 During this MAY DAY HOLIDAY endless LINES WOULD BE crowded
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A Crowded City
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作者 YIN PUMIN 《Beijing Review》 2009年第52期18-19,共2页
Over 4 million vehicles on road challenge Beijing’s city management Beijing, the city once known as the kingdom of bicycles, has become clogged with automobiles, the Beijing Municipal Government Publicity Office said... Over 4 million vehicles on road challenge Beijing’s city management Beijing, the city once known as the kingdom of bicycles, has become clogged with automobiles, the Beijing Municipal Government Publicity Office said on December 18. 展开更多
关键词 A Crowded City OFFICE
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