The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is...The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is to present a test of heteroscedasticity for nonlinear semiparametric regression models with nonparametric variance function. The validity of the proposed test is illustrated by two simulated examples and a real data example.展开更多
This article introduces a novel low rank approximation (LRA)-based model to detect the functional regions with the data from about 15 million social media check-in records during a year-long period in Shanghai, China....This article introduces a novel low rank approximation (LRA)-based model to detect the functional regions with the data from about 15 million social media check-in records during a year-long period in Shanghai, China. We identified a series of latent structures, named latent spatio-temporal activity structures. While interpreting these structures, we can obtain a series of underlying associations between the spatial and temporal activity patterns. Moreover, we can not only reproduce the observed data with a lower dimensional representative, but also project spatio-temporal activity patterns in the same coordinate system. With the K-means clustering algorithm, five significant types of clusters that are directly annotated with a combination of temporal activities can be obtained, providing a clear picture of the correlation between the groups of regions and different activities at different times during a day. Besides the commercial and transportation dominant areas, we also detected two kinds of residential areas, the developed residential areas and the developing residential areas.We further interpret the spatial distribution of these clusters using urban form analytics. The results are highly consistent with the government planning in the same periods, indicating that our model is applicable to infer the functional regions from social media check-in data and can benefit a wide range of fields, such as urban planning, public services, and location-based recommender systems.展开更多
In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in th...In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper.Firstly,the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs;Secondly,use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots(including real root and virtual roots);Finally,the phase-angle jump check function is used for checking calculation,and then the only real root can be determined as the actual fault distance,thereby achieving the purpose of high-precision fault location.MATLAB simulation results show that the proposed new algorithm is feasible and effective with high fault location accuracy and good versatility.展开更多
目的:完善我院静脉用药集中调配中心(PIVAS)合理用药审核系统,加强合理用药审核的准确性,提高工作效率。方法:找出我院现有合理用药审核系统功能的不足之处,对其进行功能改进和完善,并对功能完善前、后3个月的相关指标进行统计、比较。...目的:完善我院静脉用药集中调配中心(PIVAS)合理用药审核系统,加强合理用药审核的准确性,提高工作效率。方法:找出我院现有合理用药审核系统功能的不足之处,对其进行功能改进和完善,并对功能完善前、后3个月的相关指标进行统计、比较。结果与结论:针对系统中存在的"问题医嘱"不能有效反馈或漏停,新旧医嘱、已审核与未审核医嘱、已停医嘱与正常医嘱等在系统中不能明确区分及查看等不足,在系统中增加了医嘱拒发功能以及多项筛选和查询功能。新功能的使用,使人均日审核医嘱数增加(96.5组vs.144.8组),日处理退费医嘱数(158.3组vs.47.6组)、日处理漏审医嘱数(0.32组vs.0组)、日处理多余打包药品医嘱数(2.1组vs.0组)以及日处理停医嘱拒发时间(15 min vs.0.028 min)等降低,使医嘱审核各项操作更简便、快捷,提高了医嘱审核的准确性和效率,减少了不合理医嘱的执行。展开更多
基金Supported by the Natural Science Foundation of Jiangsu Province (BK2008284)
文摘The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is to present a test of heteroscedasticity for nonlinear semiparametric regression models with nonparametric variance function. The validity of the proposed test is illustrated by two simulated examples and a real data example.
基金the Open Research Fund Program of Shenzhen Key Laboratory of Spatial Smart Sensing and Services%sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry(grant number 50-20150618)%National Natural Science Foundation of China (grant numbers 41001220, 51378512, 41571397, and 41501442)This work was also supported by the Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund
文摘This article introduces a novel low rank approximation (LRA)-based model to detect the functional regions with the data from about 15 million social media check-in records during a year-long period in Shanghai, China. We identified a series of latent structures, named latent spatio-temporal activity structures. While interpreting these structures, we can obtain a series of underlying associations between the spatial and temporal activity patterns. Moreover, we can not only reproduce the observed data with a lower dimensional representative, but also project spatio-temporal activity patterns in the same coordinate system. With the K-means clustering algorithm, five significant types of clusters that are directly annotated with a combination of temporal activities can be obtained, providing a clear picture of the correlation between the groups of regions and different activities at different times during a day. Besides the commercial and transportation dominant areas, we also detected two kinds of residential areas, the developed residential areas and the developing residential areas.We further interpret the spatial distribution of these clusters using urban form analytics. The results are highly consistent with the government planning in the same periods, indicating that our model is applicable to infer the functional regions from social media check-in data and can benefit a wide range of fields, such as urban planning, public services, and location-based recommender systems.
基金supported by National Nature Science Foundation of China(51507031).
文摘In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper.Firstly,the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs;Secondly,use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots(including real root and virtual roots);Finally,the phase-angle jump check function is used for checking calculation,and then the only real root can be determined as the actual fault distance,thereby achieving the purpose of high-precision fault location.MATLAB simulation results show that the proposed new algorithm is feasible and effective with high fault location accuracy and good versatility.
文摘目的:完善我院静脉用药集中调配中心(PIVAS)合理用药审核系统,加强合理用药审核的准确性,提高工作效率。方法:找出我院现有合理用药审核系统功能的不足之处,对其进行功能改进和完善,并对功能完善前、后3个月的相关指标进行统计、比较。结果与结论:针对系统中存在的"问题医嘱"不能有效反馈或漏停,新旧医嘱、已审核与未审核医嘱、已停医嘱与正常医嘱等在系统中不能明确区分及查看等不足,在系统中增加了医嘱拒发功能以及多项筛选和查询功能。新功能的使用,使人均日审核医嘱数增加(96.5组vs.144.8组),日处理退费医嘱数(158.3组vs.47.6组)、日处理漏审医嘱数(0.32组vs.0组)、日处理多余打包药品医嘱数(2.1组vs.0组)以及日处理停医嘱拒发时间(15 min vs.0.028 min)等降低,使医嘱审核各项操作更简便、快捷,提高了医嘱审核的准确性和效率,减少了不合理医嘱的执行。
