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The Impacts of Mosquito Density and Meteorological Factors on Dengue Fever Epidemics in Guangzhou, China, 2006-2014: a Time-series Analysis 被引量:12
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作者 SHEN Ji Chuan LUO Lei +4 位作者 LI Li JING Qin Long OU Chun Quan YANG Zhi Cong CHEN Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第5期321-329,共9页
Objective To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China. Methods The monthly number of DF cases, Breteau Index ... Objective To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China. Methods The monthly number of DF cases, Breteau Index (BI), and meteorological measures during 2006-2014 recorded in Guangzhou, China, were assessed. A negative binomial regression model was used to evaluate the relationships between BI, meteorological factors, and the monthly number of DF cases. Results A total of 39,697 DF cases were detected in Guangzhou during the study period. DF incidence presented an obvious seasonal pattern, with most cases occurring from June to November. The current month's BI, average temperature (Tare), previous month's minimum temperature (Train), and Tare were positively associated with DF incidence. A threshold of 18.25℃ was found in the relationship between the current month's Tmin and DF incidence. Conclusion Mosquito density, Tove, and Tmin play a critical role in DF transmission in Guangzhou. These findings could be useful in the development of a DF early warning system and assist in effective control and prevention strategies in the DF epidemic. 展开更多
关键词 Breteau index Dengue fever Meteorological factors negative binomial regression model
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Safety Analysis of Riding at Intersection Entrance Using Video Recognition Technology 被引量:1
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作者 Xingjian Xue Linjuan Ge +3 位作者 Longxin Zeng Weiran Li Rui Song Neal N.Xiong 《Computers, Materials & Continua》 SCIE EI 2022年第9期5135-5148,共14页
To study riding safety at intersection entrance,video recognition technology is used to build vehicle-bicycle conflict models based on the Bayesian method.It is analyzed the relationship among the width of nonmotorize... To study riding safety at intersection entrance,video recognition technology is used to build vehicle-bicycle conflict models based on the Bayesian method.It is analyzed the relationship among the width of nonmotorized lanes at the entrance lane of the intersection,the vehicle-bicycle soft isolation form of the entrance lane of intersection,the traffic volume of right-turning motor vehicles and straight-going non-motor vehicles,the speed of right-turning motor vehicles,and straight-going non-motor vehicles,and the conflict between right-turning motor vehicles and straight-going nonmotor vehicles.Due to the traditional statistical methods,to overcome the discreteness of vehicle-bicycle conflict data and the differences of influencing factors,the Bayesian random effect Poisson-log-normal model and random effect negative binomial regression model are established.The results show that the random effect Poisson-log-normal model is better than the negative binomial distribution of random effects;The width of non-motorized lanes,the form of vehicle-bicycle soft isolation,the traffic volume of right-turning motor vehicles,and the coefficients of straight traffic volume obey a normal distribution.Among them,the type of vehicle-bicycle soft isolation facilities and the vehicle-bicycle traffic volumes are significantly positively correlated with the number of vehicle-bicycle conflicts.The width of non-motorized lanes is significantly negatively correlated with the number of vehicle-bicycle conflicts.Peak periods and flat periods,the average speed of right-turning motor vehicles,and the average speed of straight-going non-motor vehicles have no significant influence on the number of vehicle-bicycle conflicts. 展开更多
关键词 Video recognition technology vehicle-bicycle conflict intersection entrance random effect poisson-log-normal model random effect negative binomial regression model
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Crash Frequency Analysis 被引量:3
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作者 Azad Abdulhafedh 《Journal of Transportation Technologies》 2016年第4期169-180,共12页
Modeling highway traffic crash frequency is an important approach for identifying high crash risk areas that can help transportation agencies allocate limited resources more efficiently, and find preventive measures. ... Modeling highway traffic crash frequency is an important approach for identifying high crash risk areas that can help transportation agencies allocate limited resources more efficiently, and find preventive measures. This paper applies a Poisson regression model, Negative Binomial regression model and then proposes an Artificial Neural Network model to analyze the 2008-2012 crash data for the Interstate I-90 in the State of Minnesota in the US. By comparing the prediction performance between these three models, this study demonstrates that the Neural Network is an effective alternative method for predicting highway crash frequency. 展开更多
关键词 Poisson regression negative binomial regression Artificial Neural Network Crash Frequency
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Predictors of the Aggregate of COVID-19 Cases and Its Case-Fatality: A Global Investigation Involving 120 Countries
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作者 Sarah Al-Gahtani Mohamed Shoukri Maha Al-Eid 《Open Journal of Statistics》 2021年第2期259-277,共19页
<strong>Objective</strong><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"><strong>: </strong>Since the... <strong>Objective</strong><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"><strong>: </strong>Since the identification of COVID-19 in December 2019 as a pandemic, over 4500 research papers were published with the term “COVID-19” contained in its title. Many of these reports on the COVID-19 pandemic suggested that the coronavirus was associated with more serious chronic diseases and mortality particularly in patients with chronic diseases regardless of country and age. Therefore, there is a need to understand how common comorbidities and other factors are associated with the risk of death due to COVID-19 infection. Our investigation aims at exploring this relationship. Specifically, our analysis aimed to explore the relationship between the total number of COVID-19 cases and mortality associated with COVID-19 infection accounting for other risk factors. </span><b><span style="font-family:Verdana;">Methods</span></b><span style="font-family:Verdana;">: Due to the presence of over dispersion, the Negative Binomial Regression is used to model the aggregate number of COVID-19 cases. Case-fatality associated with this infection is modeled as an outcome variable using machine learning predictive multivariable regression. The data we used are the COVID-19 cases and associated deaths from the start of the pandemic up to December 02-2020, the day Pfizer was granted approval for their new COVID-19 vaccine. </span><b><span style="font-family:Verdana;">Results</span></b><span style="font-family:Verdana;">: Our analysis found significant regional variation in case fatality. Moreover, the aggregate number of cases had several risk factors including chronic kidney disease, population density and the percentage of gross domestic product spent on healthcare. </span><b><span style="font-family:Verdana;">The Conclusions</span></b><span style="font-family:Verdana;">: There are important regional variations in COVID-19 case fatality. We identified three factors to be significantly correlated with case fatality</span></span></span></span><span style="font-family:Verdana;">.</span> 展开更多
关键词 Intraclass Correlation Coefficient Hierarchical Data Structure negative binomial regression Data Splitting Mixed Effects Linear regression Model
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Dynamic road crime risk prediction with urban open data
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作者 Binbin ZHOU Longbiao CHEN +3 位作者 Fangxun ZHOU Shijian LI Sha ZHAO Gang PAN 《Frontiers of Computer Science》 SCIE EI CSCD 2022年第1期113-125,共13页
Crime risk prediction is helpful for urban safety and citizens’life quality.However,existing crime studies focused on coarse-grained prediction,and usually failed to capture the dynamics of urban crimes.The key chall... Crime risk prediction is helpful for urban safety and citizens’life quality.However,existing crime studies focused on coarse-grained prediction,and usually failed to capture the dynamics of urban crimes.The key challenge is data sparsity,since that 1)not all crimes have been recorded,and 2)crimes usually occur with low frequency.In this paper,we propose an effective framework to predict fine-grained and dynamic crime risks in each road using heterogeneous urban data.First,to address the issue of unreported crimes,we propose a cross-aggregation soft-impute(CASI)method to deal with possible unreported crimes.Then,we use a novel crime risk measurement to capture the crime dynamics from the perspective of influence propagation,taking into consideration of both time-varying and location-varying risk propagation.Based on the dynamically calculated crime risks,we design contextual features(i.e.,POI distributions,taxi mobility,demographic features)from various urban data sources,and propose a zero-inflated negative binomial regression(ZINBR)model to predict future crime risks in roads.The experiments using the real-world data from New York City show that our framework can accurately predict road crime risks,and outperform other baseline methods. 展开更多
关键词 crime prediction road crime risk urban computing data sparsity zero-inflated negative binomial regression
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1995-2015年中国老年人口迁移的空间格局与影响因素
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作者 刘晔 黄翠盈 +2 位作者 武荣伟 潘泽瀚 古恒宇 《Journal of Geographical Sciences》 SCIE CSCD 2022年第12期2541-2559,共19页
Although China was one of the countries with the fastest-growing aging population in the world,limited scholarly attention has been paid to migration among older adults in China.The full picture of their migration in ... Although China was one of the countries with the fastest-growing aging population in the world,limited scholarly attention has been paid to migration among older adults in China.The full picture of their migration in the entire country over time remains unknown.This study examines the spatial patterns of older interprovincial migration flows and their drivers in China over the period 1995 to 2015,using four waves of census data and intercensal population sample survey data.Results from eigenvector spatial filtering negative binomial regressions indicate that older adults tend to migrate away from low cost-of-living rural areas to high cost-of-living urban and rural areas,moving away from areas with extreme temperature differences.The location of their grandchildren is among the most important attractions.Our findings suggest that family-oriented migration is more common than amenity-led migration among retired Chinese older adults,and the cost-of-living is an indicator of economic opportunities for adult children and the quality of senior care services. 展开更多
关键词 interprovincial migration older adults eigenvector spatial filtering negative binomial regression models China
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