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Intelligent In-Vehicle Safety System Based on Yolov5
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作者 biyun chen Wei Cai Jinwen Zhu 《Journal of Computer and Communications》 2024年第3期207-218,共12页
In order to reduce the occurrence of traffic accidents and assist drivers to avoid dangerous driving. This paper presents a smart in-vehicle safety system that utilises the Yolov5 algorithm. Yolov5 algorithm is used t... In order to reduce the occurrence of traffic accidents and assist drivers to avoid dangerous driving. This paper presents a smart in-vehicle safety system that utilises the Yolov5 algorithm. Yolov5 algorithm is used to anticipate driver fatigue and distraction behaviours, and remind drivers to pay attention to safe driving in time. The system continuously splits the frames and analyses the frame content through the video feedback from the front camera, compared to the traditional machine learning, Yolov5’s mosaic data is enhanced, resulting in a batch size enhancement of 92.3%, and it also uses the Drop Block mechanism to prevent overfitting. The hardware of this system uses STM32 microcontroller and uses system DMA interrupt control and buzzer alarm device to warn about dangerous driving behaviour. 展开更多
关键词 Behaviour Detection STM32 Pyside2 Yolov5 Dlib Open Source Library Perclos Model
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Prediction of Wordle Scores Based on ARIMA and LSTM Models
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作者 biyun chen Wenqiang Li 《Journal of Applied Mathematics and Physics》 2024年第2期543-553,共11页
This paper examines the effectiveness of the Differential autoregressive integrated moving average (ARIMA) model in comparison to the Long Short Term Memory (LSTM) neural network model for predicting Wordle user-repor... This paper examines the effectiveness of the Differential autoregressive integrated moving average (ARIMA) model in comparison to the Long Short Term Memory (LSTM) neural network model for predicting Wordle user-reported scores. The ARIMA and LSTM models were trained using Wordle data from Twitter between 7th January 2022 and 31st December 2022. User-reported scores were predicted using evaluation metrics such as MSE, RMSE, R2, and MAE. Various regression models, including XG-Boost and Random Forest, were used to conduct comparison experiments. The MSE, RMSE, R2, and MAE values for the ARIMA(0,1,1) and LSTM models are 0.000, 0.010, 0.998, and 0.006, and 0.000, 0.024, 0.987, and 0.013, respectively. The results indicate that the ARIMA model is more suitable for predicting Wordle user scores than the LSTM model. 展开更多
关键词 Time Series ARIMA LSTM Wordle PREDICTION
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冠心病患者术后运动能力及影响因素的调查研究 被引量:2
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作者 李莺 冯雪 +1 位作者 陈碧云 刘华平 《International Journal of Nursing Sciences》 CSCD 2021年第3期257-263,I0001,共8页
目的了解冠心病术后患者接受经皮冠状动脉介入治疗或冠状动脉搭桥术后运动能力,并分析其影响因素.方法采用回顾性调查,对2019年1-10月在医院心脏康复中心就诊的230例冠心病术后患者的病历资料进行分析.采用心肺运动试验测量患者的运动能... 目的了解冠心病术后患者接受经皮冠状动脉介入治疗或冠状动脉搭桥术后运动能力,并分析其影响因素.方法采用回顾性调查,对2019年1-10月在医院心脏康复中心就诊的230例冠心病术后患者的病历资料进行分析.采用心肺运动试验测量患者的运动能力,采用Zung焦虑自评量表和Zung抑郁自评量表分别测量患者的焦虑和抑郁情绪.采用卡方检验、Fisher精确检验、t检验、Mann-Whitney U检验和多元logistic回归分析方法进行统计学分析.结果在230例冠心病术后患者中,223例存在运动能力降低的情况.多元lo-gistic回归分析结果显示,焦虑(OR=1.13,95%CI:1.01~1.32,P=0.029)与冠心病术后患者运动能力降低有关.结论冠心病术后患者的运动能力较差,医护人员对患者进行干预时应考虑减轻其焦虑,根据心肺运动试验结果制订个性化运动处方,以提高患者的运动能力. 展开更多
关键词 冠心病 冠状动脉旁路移植术 经皮冠状动脉介入治疗 运动耐力 运动试验 心脏康复 焦虑 抑郁
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Estimation of chlorophyll content in Brassica napus based on unmanned aerial vehicle images 被引量:1
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作者 Yayi Huang Qiming Ma +10 位作者 Xiaoming Wu Hao Li Kun Xu Gaoxiang Ji Fang Qian Lixia Li Qian Huang Ying Long Xiaojun Zhang biyun chen Changhua Liu 《Oil Crop Science》 CSCD 2022年第3期149-155,共7页
The chlorophyll content has a direct effect on photosynthesis of crops.In order to explore a quick and convenient method for estimating the chlorophyll content of Brassica napus and facilitate efficient crop monitorin... The chlorophyll content has a direct effect on photosynthesis of crops.In order to explore a quick and convenient method for estimating the chlorophyll content of Brassica napus and facilitate efficient crop monitoring,we measured the actual value of chlorophyll with a SPAD-502 chlorophyll detector,and collected aerial images of B.napus with an unmanned aerial vehicle(UAV)carrying a RGB camera in this study.The total number of 270samples collected images were divided into regions according to the planting conditions of different B.napus varieties in the field.Then,according to the empirical formula,there were 36 colors’characteristic parameters calculated and combined.To estimate the chlorophyll content of rape,189 samples were included in the modeling set,while the other 81 samples were enrolled in the validation set for testing the accuracy of this model.After the combination of R(red),G(green)and B(blue)color channels,the results showed that the color characteristics B/(R+G),b,B/G,(G-B)/(G+B),g-b were highly connected with the measured value of chlorophyll SPAD,and the correlation coefficient between the combination based on B/(R+G)and SPAD value was 0.747.With R2=0.805,RMSE=3.343,and RE=6.84%,the regression model created using random forest had superior outcomes,according to the model comparison.This study offers a new method for quickly estimating the amount of chlorophyll in rapeseed and a workable reference for crop monitoring using the UAV platform. 展开更多
关键词 Brassica napus Unmanned aerial vehicle Red green blue images SPAD CHLOROPHYLL
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Identi cation of seed heat tolerance and its correlation with agronomic traits in Brassica napus L.
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作者 Guizhen Gao Kun Xu +5 位作者 biyun chen Xi cheng Guixin Yan Jiangwei Qiao Qian Huang Xiaoming Wu 《Oil Crop Science》 2018年第1期21-32,共12页
To better understand the effect of high temperature on seed viability, artificial aging treatments were implemented on 472 accessions of rapeseed (Brassica napus L.) by constant high temperature at 70℃for 8h. Results... To better understand the effect of high temperature on seed viability, artificial aging treatments were implemented on 472 accessions of rapeseed (Brassica napus L.) by constant high temperature at 70℃for 8h. Results showed a remarkable impact of constant heat on seed germination. After heat treatment, considerable variation was found in seed germinability, some genotypes even lost the ability to germinate. The effect of accelerated aging was highly significant. Germination parameters varied among ecotypes. Seed viability varied with different origin, and was significantly and positively correlated with seed yield per plant and dry weight of aboveground parts per plant among 14 agronomic traits. Germination traits were positively correlated with oil contents. 展开更多
关键词 BRASSICA NAPUS L. SEED VIABILITY SEED germination heat stress AGRONOMIC traits yield quality
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Urban structure and the risk of influenza A(H1N1) outbreaks in municipal districts 被引量:1
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作者 Hong Xiao Xiaoling Lin +9 位作者 Gerardo Chowell Cunrui Huang Lidong Gao biyun chen Zheng Wang Liang Zhou Xinguang He Haining Liu Xixing Zhang Huisuo Yang 《Chinese Science Bulletin》 SCIE EI CAS 2014年第5期554-562,共9页
Changsha was one of the most affected areas during the 2009 A(H1N1)influenza pandemic in China.Here,we analyze the spatial–temporal dynamics of the 2009 pandemic across Changsha municipal districts,evaluate the relat... Changsha was one of the most affected areas during the 2009 A(H1N1)influenza pandemic in China.Here,we analyze the spatial–temporal dynamics of the 2009 pandemic across Changsha municipal districts,evaluate the relationship between case incidence and the local urban spatial structure and predict high-risk areas of influenza A(H1N1).We obtained epidemiological data on all cases of influenza A(H1N1)reported across municipal districts in Changsha during period May 2009–December 2010 and data on population density and basic geographic characteristics for 239 primary schools,97 middle schools,347 universities,96 malls and markets,674 business districts and 121 hospitals.Spatial–temporal K functions,proximity models and logistic regression were used to analyze the spatial distribution pattern of influenza A(H1N1)incidence and the association between influenza A(H1N1)cases and spatial risk factors and predict the infection risks.We found that the 2009 influenza A(H1N1)was driven by a transmission wave from the center of the study area to surrounding areas and reported cases increased significantly after September 2009.We also found that the distribution of influenza A(H1N1)cases was associated with population density and the presence of nearest public places,especially universities(OR=10.166).The final predictive risk map based on the multivariate logistic analysis showed high-risk areas concentrated in the center areas of the study area associated with high population density.Our findings support the identification of spatial risk factors and highrisk areas to guide the prioritization of preventive and mitigation efforts against future influenza pandemics. 展开更多
关键词 风险图 流感 甲型 城市结构 LOGISTIC回归分析 LOGISTIC回归 城市空间结构 爆发
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