Outbreaks of hand-foot-mouth disease（HFMD） have occurred many times and caused serious health burden in China since 2008. Application of modern information technology to prediction and early response can be helpful ...Outbreaks of hand-foot-mouth disease（HFMD） have occurred many times and caused serious health burden in China since 2008. Application of modern information technology to prediction and early response can be helpful for efficient HFMD prevention and control. A seasonal auto-regressive integrated moving average（ARIMA） model for time series analysis was designed in this study. Eighty-four-month（from January 2009 to December 2015） retrospective data obtained from the Chinese Information System for Disease Prevention and Control were subjected to ARIMA modeling. The coefficient of determination（R^2）, normalized Bayesian Information Criterion（BIC） and Q-test P value were used to evaluate the goodness-of-fit of constructed models. Subsequently, the best-fitted ARIMA model was applied to predict the expected incidence of HFMD from January 2016 to December 2016. The best-fitted seasonal ARIMA model was identified as（1,0,1）（0,1,1）12, with the largest coefficient of determination（R^2=0.743） and lowest normalized BIC（BIC=3.645） value. The residuals of the model also showed non-significant autocorrelations（P_（Box-Ljung（Q））=0.299）. The predictions by the optimum ARIMA model adequately captured the pattern in the data and exhibited two peaks of activity over the forecast interval, including a major peak during April to June, and again a light peak for September to November. The ARIMA model proposed in this study can forecast HFMD incidence trend effectively, which could provide useful support for future HFMD prevention and control in the study area. Besides, further observations should be added continually into the modeling data set, and parameters of the models should be adjusted accordingly.展开更多
With dexterous hands, robots can improve the work scope and work ability significantly. As palms of the existing multi-hand robots are made of steel plates that have small contact area, the robots cannot grab firmly. ...With dexterous hands, robots can improve the work scope and work ability significantly. As palms of the existing multi-hand robots are made of steel plates that have small contact area, the robots cannot grab firmly. In this study, a new five-fingered dexterous robot hand is developed. Having flexible palm with 17 degree of freedoms （ DOFs）, the hand can grasp more stably and firm- ly. First, the forward kinematics and inverse kinematics of the fingers and the hand are calculated. Then, the connection between the force exerting on the end effectors and the torque exerting on the joint is set up, laying the foundation for the following control. Finally, through the analysis and sim- ulation of the position, velocity and acceleration, the trajectory planning has a better performance.展开更多
为提高手部康复产品的服务质量及用户满意度,提出服务质量(service quality,SQ)模型、乘积标度法(product scaling method,PSM)与逼近理想解排序法(technique for order preference by similarity to ideal solution,TOPSIS)相结合的产...为提高手部康复产品的服务质量及用户满意度,提出服务质量(service quality,SQ)模型、乘积标度法(product scaling method,PSM)与逼近理想解排序法(technique for order preference by similarity to ideal solution,TOPSIS)相结合的产品创新设计方法。以手部康复器设计为例,采用SQ模型求解用户对手部康复器各服务评价指标的期望值与感受值,通过PSM对用户期望值赋权,评估产品改进可能性;依据评价指标质量分布,对优化指标进行拆解与拓展,并指导产品设计多方案生成;运用TOPSIS法对设计方案进行综合评价,筛选出最优解,并验证方法的可行性。3种方法结合使用可弥补主观性因素和多方案生成问题,实现从需求挖掘到方案设计全流程闭环,为脑卒中人群康复产品设计提供思路与参考。展开更多
目的分析2010—2020年恩施州手足口病(hand,foot and mouth disease,HFMD)的流行特征,探讨社会经济与气象因素的影响,并评估疫情防控措施对HFMD的干预效果。方法运用ArcGIS 10.8对恩施州88个乡级行政单元的HFMD病例进行时空特征可视化;...目的分析2010—2020年恩施州手足口病(hand,foot and mouth disease,HFMD)的流行特征,探讨社会经济与气象因素的影响,并评估疫情防控措施对HFMD的干预效果。方法运用ArcGIS 10.8对恩施州88个乡级行政单元的HFMD病例进行时空特征可视化;采用贝叶斯时空模型解析社会经济与气象因素对疾病分布的影响;使用SEIR模型估算易感人群人数与比例;构建时间序列模型,预测2020年发病趋势并量化疫情防控措施效果。结果2010—2020年累计报告病例58954例,年均发病率为11.90/10万,死亡率为0.01/10万,≤5岁儿童占发病人数的93.20%;居民储蓄存款每增加1个标准差单位,发病率下降1.1%(P<0.05);医院床位数与发病率呈正相关;气温升高(β=0.182)和降水增多(β=0.229)增加发病风险;疫情防控措施使发病数每月减少415例(P=0.049),但防控放松后,2020年12月发病数较2019年同期增长266.6%,呈现补偿性流行特征。结论本研究揭示了恩施州HFMD的时空分布特征及社会经济气象驱动因素,量化了疫情防控措施效果,为山区传染病精准防控提供了多维度依据。展开更多
Currently, Granger-Geweke causality models have been widely applied to investigate the dynamic direction relationships among brain regions. In a previous study, we have found that the right hand finger-tapping task ca...Currently, Granger-Geweke causality models have been widely applied to investigate the dynamic direction relationships among brain regions. In a previous study, we have found that the right hand finger-tapping task can produce relatively reliable brain response. As an extension of our previous study, we developed an algorithm based on the classical Granger- Geweke causality model to further investigate the effective connectivity of three brain regions (left primary motor cortex (M1), supplementary motor area (SMA) and right cerebellum) that showed the most robust brain activations. Our computational results not only confirm the strong linear feedback among SMA, M1 and right cerebellum, but also demonstrate that M1 is the hub of these three regions indicated by the anatomy research. Moreover, the model predicts the high intermediate node density existing in the area between SMA and M1, which will stimulate the imaging experimentalists to carry out new experiments to validate this postulation.展开更多
In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile sta...In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile stations, and divide mobile stations into three classes based on the predicted speeds: fast, medium-speed, and slow.Then, according to the mobility classification,network conditions, and service types, mobile stations will be handoff to the proper target networks prior to the deterioration of the currently operating channel. We further develop an analytical model to evaluate the performance of such a hierarchical system with different speed classes and service types. Simulations and analytical results show that the proposed handoff algorithm can significantly improve the network performance in terms of the handoff failure probability, unnecessary handoff probability, and network throughput, comparing with the traditional algorithms.展开更多
Finite-difference time-domain(FDTD) method is used to simulate the propagation of electromagnetic wave in left-handed material slab(LHMs) with cold plasma model The effects of optical propagation in the left-handed ma...Finite-difference time-domain(FDTD) method is used to simulate the propagation of electromagnetic wave in left-handed material slab(LHMs) with cold plasma model The effects of optical propagation in the left-handed material compared to convex lens are discussed.The wider the LHMs is,the stronger electric field of focusing image in left-handed material slab is confirmed by the simulation with various slab length.However,the outer image point location would slightly moves to the LHMs side when the length of LHMs is reduced.展开更多
Zambia largely depends on the international second-hand car (SHC) market for their motor vehicle supply. The importation of Second hand Cars in Zambia presents a time series problem. The data used in this paper is mon...Zambia largely depends on the international second-hand car (SHC) market for their motor vehicle supply. The importation of Second hand Cars in Zambia presents a time series problem. The data used in this paper is monthly data on SHC importation from 1st January, 2014 to 31st December, 2016. Data was analyzed using Exponential Smoothing (ES) and Autoregressive Integrated Moving Average (ARIMA) models. The results showed that ARIMA (2, 1, 2) was the best fit for the SHC importation since its errors were smaller than those of the SES, DES and TES. The four error measures used were Root-mean-square error (RMSE), Mean absolute error (MAE), Mean percentage error (MPE) and Mean absolute percentage error (MAPE). The forecasts were also produced using the ARIMA (2, 1, 2) model for the next 18 months from January 2017. Although there is percentage increase of 90.6% from November 2015 to December 2016, the SHC importation generally is on the decrease in Zambia with percentage change of 59.5% from January 2014 to December 2016. The forecasts also show a gradual percentage decrease of 1.12% by June 2018. These results are more useful to policy and decision makers of Government departments such as Zambia Revenue Authority (ZRA) and Road Development Agency (RDA) in a bid to plan and execute their duties effectively.展开更多
基金financially supported by the Health and Family Planning Commission of Hubei Province(No.WJ2017F047)the Health and Family Planning Commission of Wuhan(No.WG17D05)
文摘Outbreaks of hand-foot-mouth disease（HFMD） have occurred many times and caused serious health burden in China since 2008. Application of modern information technology to prediction and early response can be helpful for efficient HFMD prevention and control. A seasonal auto-regressive integrated moving average（ARIMA） model for time series analysis was designed in this study. Eighty-four-month（from January 2009 to December 2015） retrospective data obtained from the Chinese Information System for Disease Prevention and Control were subjected to ARIMA modeling. The coefficient of determination（R^2）, normalized Bayesian Information Criterion（BIC） and Q-test P value were used to evaluate the goodness-of-fit of constructed models. Subsequently, the best-fitted ARIMA model was applied to predict the expected incidence of HFMD from January 2016 to December 2016. The best-fitted seasonal ARIMA model was identified as（1,0,1）（0,1,1）12, with the largest coefficient of determination（R^2=0.743） and lowest normalized BIC（BIC=3.645） value. The residuals of the model also showed non-significant autocorrelations（P_（Box-Ljung（Q））=0.299）. The predictions by the optimum ARIMA model adequately captured the pattern in the data and exhibited two peaks of activity over the forecast interval, including a major peak during April to June, and again a light peak for September to November. The ARIMA model proposed in this study can forecast HFMD incidence trend effectively, which could provide useful support for future HFMD prevention and control in the study area. Besides, further observations should be added continually into the modeling data set, and parameters of the models should be adjusted accordingly.
基金Supported by Beijing Science Foundation(4122065)National Science Foundation for Distinguished Young Scholar(60925014)
文摘With dexterous hands, robots can improve the work scope and work ability significantly. As palms of the existing multi-hand robots are made of steel plates that have small contact area, the robots cannot grab firmly. In this study, a new five-fingered dexterous robot hand is developed. Having flexible palm with 17 degree of freedoms （ DOFs）, the hand can grasp more stably and firm- ly. First, the forward kinematics and inverse kinematics of the fingers and the hand are calculated. Then, the connection between the force exerting on the end effectors and the torque exerting on the joint is set up, laying the foundation for the following control. Finally, through the analysis and sim- ulation of the position, velocity and acceleration, the trajectory planning has a better performance.
文摘为提高手部康复产品的服务质量及用户满意度,提出服务质量(service quality,SQ)模型、乘积标度法(product scaling method,PSM)与逼近理想解排序法(technique for order preference by similarity to ideal solution,TOPSIS)相结合的产品创新设计方法。以手部康复器设计为例,采用SQ模型求解用户对手部康复器各服务评价指标的期望值与感受值,通过PSM对用户期望值赋权,评估产品改进可能性;依据评价指标质量分布,对优化指标进行拆解与拓展,并指导产品设计多方案生成;运用TOPSIS法对设计方案进行综合评价,筛选出最优解,并验证方法的可行性。3种方法结合使用可弥补主观性因素和多方案生成问题,实现从需求挖掘到方案设计全流程闭环,为脑卒中人群康复产品设计提供思路与参考。
文摘目的分析2010—2020年恩施州手足口病(hand,foot and mouth disease,HFMD)的流行特征,探讨社会经济与气象因素的影响,并评估疫情防控措施对HFMD的干预效果。方法运用ArcGIS 10.8对恩施州88个乡级行政单元的HFMD病例进行时空特征可视化;采用贝叶斯时空模型解析社会经济与气象因素对疾病分布的影响;使用SEIR模型估算易感人群人数与比例;构建时间序列模型,预测2020年发病趋势并量化疫情防控措施效果。结果2010—2020年累计报告病例58954例,年均发病率为11.90/10万,死亡率为0.01/10万,≤5岁儿童占发病人数的93.20%;居民储蓄存款每增加1个标准差单位,发病率下降1.1%(P<0.05);医院床位数与发病率呈正相关;气温升高(β=0.182)和降水增多(β=0.229)增加发病风险;疫情防控措施使发病数每月减少415例(P=0.049),但防控放松后,2020年12月发病数较2019年同期增长266.6%,呈现补偿性流行特征。结论本研究揭示了恩施州HFMD的时空分布特征及社会经济气象驱动因素,量化了疫情防控措施效果,为山区传染病精准防控提供了多维度依据。
文摘Currently, Granger-Geweke causality models have been widely applied to investigate the dynamic direction relationships among brain regions. In a previous study, we have found that the right hand finger-tapping task can produce relatively reliable brain response. As an extension of our previous study, we developed an algorithm based on the classical Granger- Geweke causality model to further investigate the effective connectivity of three brain regions (left primary motor cortex (M1), supplementary motor area (SMA) and right cerebellum) that showed the most robust brain activations. Our computational results not only confirm the strong linear feedback among SMA, M1 and right cerebellum, but also demonstrate that M1 is the hub of these three regions indicated by the anatomy research. Moreover, the model predicts the high intermediate node density existing in the area between SMA and M1, which will stimulate the imaging experimentalists to carry out new experiments to validate this postulation.
基金supported by Natural Science Foundation of China(61372125)973 project(2013CB329104)+1 种基金the National High-Tech R&D Program(863 Program 2015AA01A705)the open research fund of National Mobile Communications Research Laboratory,Southeast University(2013D01)
文摘In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile stations, and divide mobile stations into three classes based on the predicted speeds: fast, medium-speed, and slow.Then, according to the mobility classification,network conditions, and service types, mobile stations will be handoff to the proper target networks prior to the deterioration of the currently operating channel. We further develop an analytical model to evaluate the performance of such a hierarchical system with different speed classes and service types. Simulations and analytical results show that the proposed handoff algorithm can significantly improve the network performance in terms of the handoff failure probability, unnecessary handoff probability, and network throughput, comparing with the traditional algorithms.
基金Supported by the National Natural Science Foundation of China(60601028)
文摘Finite-difference time-domain(FDTD) method is used to simulate the propagation of electromagnetic wave in left-handed material slab(LHMs) with cold plasma model The effects of optical propagation in the left-handed material compared to convex lens are discussed.The wider the LHMs is,the stronger electric field of focusing image in left-handed material slab is confirmed by the simulation with various slab length.However,the outer image point location would slightly moves to the LHMs side when the length of LHMs is reduced.
文摘Zambia largely depends on the international second-hand car (SHC) market for their motor vehicle supply. The importation of Second hand Cars in Zambia presents a time series problem. The data used in this paper is monthly data on SHC importation from 1st January, 2014 to 31st December, 2016. Data was analyzed using Exponential Smoothing (ES) and Autoregressive Integrated Moving Average (ARIMA) models. The results showed that ARIMA (2, 1, 2) was the best fit for the SHC importation since its errors were smaller than those of the SES, DES and TES. The four error measures used were Root-mean-square error (RMSE), Mean absolute error (MAE), Mean percentage error (MPE) and Mean absolute percentage error (MAPE). The forecasts were also produced using the ARIMA (2, 1, 2) model for the next 18 months from January 2017. Although there is percentage increase of 90.6% from November 2015 to December 2016, the SHC importation generally is on the decrease in Zambia with percentage change of 59.5% from January 2014 to December 2016. The forecasts also show a gradual percentage decrease of 1.12% by June 2018. These results are more useful to policy and decision makers of Government departments such as Zambia Revenue Authority (ZRA) and Road Development Agency (RDA) in a bid to plan and execute their duties effectively.
