scholarly journals Error-Aware Spatio-Temporal Aggregation in the Model Web

Author(s):  
Christoph Stasch ◽  
Edzer Pebesma ◽  
Benedikt Graeler ◽  
Lydia Gerharz
Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 218
Author(s):  
Changjun Wan ◽  
Changxiu Cheng ◽  
Sijing Ye ◽  
Shi Shen ◽  
Ting Zhang

Precipitation is an essential climate variable in the hydrologic cycle. Its abnormal change would have a serious impact on the social economy, ecological development and life safety. In recent decades, many studies about extreme precipitation have been performed on spatio-temporal variation patterns under global changes; little research has been conducted on the regionality and persistence, which tend to be more destructive. This study defines extreme precipitation events by percentile method, then applies the spatio-temporal scanning model (STSM) and the local spatial autocorrelation model (LSAM) to explore the spatio-temporal aggregation characteristics of extreme precipitation, taking China in July as a case. The study result showed that the STSM with the LSAM can effectively detect the spatio-temporal accumulation areas. The extreme precipitation events of China in July 2016 have a significant spatio-temporal aggregation characteristic. From the spatial perspective, China’s summer extreme precipitation spatio-temporal clusters are mainly distributed in eastern China and northern China, such as Dongting Lake plain, the Circum-Bohai Sea region, Gansu, and Xinjiang. From the temporal perspective, the spatio-temporal clusters of extreme precipitation are mainly distributed in July, and its occurrence was delayed with an increase in latitude, except for in Xinjiang, where extreme precipitation events often take place earlier and persist longer.


2021 ◽  
Author(s):  
Avishkar Saha ◽  
Oscar Mendez ◽  
Chris Russell ◽  
Richard Bowden

2014 ◽  
Vol 47 (3) ◽  
pp. 4571-4577
Author(s):  
Tomonori Sadamoto ◽  
Ikuma Muto ◽  
Takayuki Ishizaki ◽  
Masakazu Koike ◽  
Jun-ichi Imura

Parasitology ◽  
2012 ◽  
Vol 139 (7) ◽  
pp. 915-925 ◽  
Author(s):  
G. DEVEVEY ◽  
D. BRISSON

SUMMARYParasites are often aggregated on a minority of the individuals in their host populations. Although host characteristics are commonly presumed to explain parasite aggregation on hosts, spatio-temporal aggregation of parasites during their host-seeking stages may have a dominant effect on the aggregation on hosts. We aimed to quantify, using mixed models, repeatability and autocorrelation analyses, the degree to which the aggregation of blacklegged ticks (Ixodes scapularis) on white-footed mice (Peromyscus leucopus) is influenced by spatio-temporal distributions of the host-seeking ticks and by heterogeneity among mice. Host-seeking ticks were spatially aggregated at both the larval and nymphal life-stages. However, this spatial aggregation accounted for little of the variation in larval and nymphal burdens observed on mice (3% and 0%, respectively). Conversely, mouse identity accounted for a substantial proportion of the variance in tick burdens. Mouse identity was a significant explanatory factor as the majority of ticks parasitized a consistent set of mice throughout the activity seasons. Of the characteristics associated with mouse identity investigated, only gender affected larval burdens, and body mass and home range sizes in males were correlated with nymphal burdens. These analyses suggest that aggregation of ticks on a minority of mice does not result from the distribution of host-seeking ticks but from characteristics of the hosts.


2020 ◽  
Vol 12 (17) ◽  
pp. 2845
Author(s):  
Jovan Kovačević ◽  
Željko Cvijetinović ◽  
Dmitar Lakušić ◽  
Nevena Kuzmanović ◽  
Jasmina Šinžar-Sekulić ◽  
...  

The inventory of woody vegetation is of great importance for good forest management. Advancements of remote sensing techniques have provided excellent tools for such purposes, reducing the required amount of time and labor, yet with high accuracy and the information richness. Sentinel-2 is one of the relatively new satellite missions, whose 13 spectral bands and short revisit time proved to be very useful when it comes to forest monitoring. In this study, the novel spatio-temporal classification framework for mapping woody vegetation from Sentinel-2 multitemporal data has been proposed. The used framework is based on the probability random forest classification, where temporal information is explicitly defined in the model. Because of this, several predictions are made for each pixel of the study area, which allow for specific spatio-temporal aggregation to be performed. The proposed methodology has been successfully applied for mapping eight potential forest and shrubby vegetation types over the study area of Serbia. Several spatio-temporal aggregation approaches have been tested, divided into two main groups: pixel-based and neighborhood-based. The validation metrics show that determining the most common vegetation type classes in the neighborhood of 5 × 5 pixels provides the best results. The overall accuracy and kappa coefficient obtained from five-fold cross validation of the results are 82.97% and 0.75, respectively. The corresponding producer’s accuracies range from 36.74% to 97.99% and user’s accuracies range from 46.31% to 98.43%. The proposed methodology proved to be applicable for mapping woody vegetation in Serbia and shows a potential to be implemented in other areas as well. Further testing is necessary to confirm such assumptions.


IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 137122-137135 ◽  
Author(s):  
Abel Diaz Berenguer ◽  
Meshia Cedric Oveneke ◽  
Habib-Ur-Rehman Khalid ◽  
Mitchel Alioscha-Perez ◽  
Andre Bourdoux ◽  
...  

1981 ◽  
Vol 17 (1-3) ◽  
pp. 387-407 ◽  
Author(s):  
Bruce E. Flinchbaugh ◽  
B. Chandrasekaran

2005 ◽  
Vol 23 (1) ◽  
pp. 61-102 ◽  
Author(s):  
Yufei Tao ◽  
Dimitris Papadias

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