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The taxonomic status of previously misplaced species of an ant-like stone beetle from Spanish amber (Albian) is clarified. Specimens of Kachinus magnificus (originally placed as incertae sedis within Scydmaenitae) were re-examined and their characters were found different from those of the type species of Kachinus from Myanmar amber. Consequently, Archeutheia gen. nov. is proposed to accommodate the Spanish species, resulting in Archeutheia magnifica comb. nov. Moreover, in a comprehensive phylogenetic analysis Archeutheia was placed as a sister group to extant Eutheia, within the tribe Eutheiini of Cephenniitae. A specimen of an undetermined genus from Myanmar amber clearly belonging in Cephenniini is also recorded. Both taxa represent the first definite Cretaceous Cephenniitae, a supertribe whose recent members are distributed on all continents but are especially diverse in the Oriental and East Palaearctic regions. This finding demonstrates a diversification of two presently most species-rich tribes of Cephenniitae already in Early Cretaceous. Archeutheia is strikingly similar to the extant species of Eutheia and Veraphis, showing male dimorphic characters (modified protrochanters) and antennal cavities characteristic of Palaearctic Eutheiini. This fact suggests a long morphological stability in the supertribe. A previously proposed hypothesis of an early presence of the Cephenniitae in the Northern Hemisphere is for the first time supported by the fossil record, and the palaeolocalities (western Europe and Southeast Asia) demonstrate a wide distribution of Cephenniitae in the Cretaceous and an early split of its ancestral lineage. 相似文献
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To settle the difficulties of the shortage of oceanographic research vessels in our country, the National Natural Science Foundation Committee of China founded Oceanographic Research Vessel Sharing Plan in 2009. It is aimed at enhancing efficiency and optimization of the vessel resources,and coordinating the use demands of vessels for the different foundation projects and the efficient use of the research vessels. We have summarized the achievements made in the Plan from 2010 to 2014, as well as the use system of the research vessels sharing, the specific operating mode ,the organization and the management framework of the Plan. In the end, we put forward our suggestions on the improvement of the Plan after the primary analysis of the present situation of the sharing of the survey data and the existing problems. 相似文献
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在信息社会,工作流技术在现代组织管理中发挥的作用越来越大。本文将Activiti工作流技术引入地理国情数据生产管理中,提出了适用于地理国情数据生产管理的工作流模型,探讨了地理国情生产过程中数据的组织与管理,并研发了工作流系统,实现了生产管理中任务分配、数据流转、进度监督等业务流程,有利于地理国情数据生产的跟踪管理,提高了生产效率。 相似文献
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Multiresolution segmentation (MRS) algorithm has been widely used to handle very-high-resolution (VHR) remote sensing images in the past decades. Unfortunately, segmentation quality is limited by the dependency of parameter selection on users’ experience and diverse images. Contrarily, the segmentation by weighted aggregation (SWA) can partly overcome the above limitations and produce an optimal segmentation for maximizing the homogeneity within segments and the heterogeneity across segments. However, SWA is solely tested and justified with digital photos in computer vision field instead of VHR images. This study aims at evaluating SWA performance on VHR imagery. First, multiscale spectral, shape, and texture features are defined to measure homogeneity of image objects for segmentation. Second, SWA is implemented to handle QuickBird, unmanned aerial vehicle (UAV), and GF-1 VHR images and further compared with MRS in eCognition software to demonstrate the applicability of SWA to diverse images in building, vegetation and water, forest stands, farmland, and mountain areas. Third, the results are fully evaluated with quantitative measurements on segmented objects and classification-based accuracy assessment on geographic information system vector data. The results indicate that SWA can produce higher quality segmentations, need fewer parameters and manual interventions, create fewer segmentation levels, incorporate more features, and obtain larger classification accuracy than MRS. 相似文献
228.
Alex David Singleton Seth Spielman Chris Brunsdon 《International journal of geographical information science》2016,30(8):1507-1521
When conducting research within a framework of Geographic Information Science (GISc), the scientific validity of this work can be argued as highly dependent upon the extent to which the methods employed are reproducible, and that, in the strictest sense, can only be fully achieved by implementing transparent workflows that utilize both open source software and openly available data. After considering the scientific implications of non-reproducible methods, we provide a review of both open source Geographic Information Systems (GIS) and openly available data, before describing an integrated model for Open GISc. We conclude with a critical review of this embryonic paradigm, with directions for future development in supporting spatial data infrastructure. 相似文献
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Understanding changes in the size of tropical cyclone (TC) wind and rain fields before landfall can improve identification of areas that may experience damage. We examine 25 Atlantic basin TCs for 36 h before gale-force winds (R17) cross land. Rain field extents are measured from satellite estimates of rain rates using a Geographic Information System. In each quadrant, R17 is obtained from the Extended Best Track data-set and correlated with the extent of the rain field. In general, both fields expand prior to landfall. The non-linearity of this trend poses problems for persistence forecast models. The largest wind fields are located over the Atlantic Ocean. Correlations between wind and rain field extent are strongly positive for Atlantic cases regardless of whether extratropical transition (ET) occurs and are associated with the direction of vertical wind shear. Poor correlations exist for Gulf observations. Rain fields extend farther towards the east during ET when vertical wind shear is stronger, but wind fields are not significantly different when separating cases based on whether or not ET occurs. As rain fields extend farther than wind fields in 33% of Gulf cases, moderately heavy rainfall may commence before damaging winds arrive, decreasing the time available for preparedness activities. 相似文献
230.
Conventional ways of trip planning using online reviews from multiple sources are often cumbersome and uncustomizable. The advance in information and communication technology (ICT) and the surge in user-generated contents (UGC) provide great opportunities to facilitate trip planning. This paper proposes a travel-planning tool by crowdsourcing multiple UGCs to provide customized information for tourists. We harvested hotel customer reviews from TripAdvisor, photo information from Flickr, and travel costs between destinations from Uber. First, we used geospatial data mining approaches to extract tourism attractions information from Flickr; identified multi-facet characteristics of hotels with natural language processing (NLP); and provided travel route recommendations with graph analysis. Second, we developed a web-based interface to let users communicate with the system interactively, which provides integrated recommendations including attractions, hotels, and visit route sequences. Two cities in the United States (i.e. Atlanta and Chicago) were used as cases to illustrate our approaches. The proposed travel planning tool is not only beneficial to support customized travel decision-making, but also supportive for hotel managers with strategic management implications. 相似文献