Search results for "database."
showing 10 items of 2119 documents
A Semantic Model to Query Spatial–Temporal Data
2013
There is a growing need for the study of spatial–temporal objects and their relationships. A common approach for this task is the use of relational databases, which unfortunately do not allow inference. In this research, we introduce a new approach that uses the concept of a “continuum” together with ontologies and semantic Web technologies. The continuum allows us to define parent–child relationships between representations of objects. It also allows us to compare the evolution of two different objects and establish the relationships between them along time. Our approach is based on the four-dimensional fluent, which is extended to obtain spatial–temporal qualitative information from the a…
Distributed image retrieval on DAISY
2006
The paper describes an application of image retrieval based on DAISY architecture (distributed architecture for intelligent system). The creation of pictorial indexes may require a number of hours depending on the size of the pictorial data base. The problem can become more complex in the case of distributed database systems. In both cases a distributed architecture can be the natural and more efficient solution. DAISY architecture is based on the concept of co-operating behavioral agents supervised by a central engagement module. Preliminary experiments, to evaluate the performance of the system, have been performed on a astronomical database and coral image
SILKNOWViz: Spatio-Temporal Data Ontology Viewer
2019
Interactive visualization of spatio-temporal data is a very active area that has experienced remarkable advances in the last decade. This is due to the emergence of fields of research such as big data and advances in hardware that allow better analysis of information. This article describes the methodology followed and the design of an open source tool, which in addition to interactively visualizing spatio-temporal data that are represented in an ontology, allows the definition of what to visualize and how to do it. The tool allows selecting, filtering and visualizing in a graphical way the entities of the ontology with spatiotemporal data, as well as the instances related to them. The grap…
Optimized search strategy for detecting scientifically strong studies on treatment through PubMed.
2011
OBJECTIVE: To develop optimal MEDLINE search strategies for retrieving sound clinical studies of the etiology, prognosis, diagnosis, prevention, or treatment of disorders in adult general medicine. DESIGN: Analytic survey of operating characteristics of search strategies developed by computerized combinations of terms selected to detect studies meeting basic methodologic criteria for direct clinical use in adult general medicine. MEASURES: The sensitivities, specificities, precision, and accuracy of 134,264 unique combinations of search terms were determined by comparison with a manual review of all articles (the "gold standard") in ten internal medicine and general medicine journals for 19…
ProQuest datubāzes lietojamības, derīguma un informācijas meklēšanas iespēju novērtējums
2022
Bakalaura darba ‘’ProQuest datubāzes lietojamības, derīguma un informācijas meklēšanas iespēju novērtējums’’ mērķis bija izpētīt šīs datubāzes lietojamību no studentu viedokļa. Pētījums tika balstīts uz pragmatisma teoriju un Mijiedarbības trīs komponentu modeli. Kā pētīšanas metodes tika izmantotas kontentanalīze un verbālais protokols. Pētījuma rezultāti apstiprināja hipotēzi, ka datubāze ir lietotājiem draudzīga ar plašām meklēšanas iespējām, kuru respondenti pēc uzdevumu veikšanas atzina par noderīgu.
GekkoFS — A Temporary Burst Buffer File System for HPC Applications
2020
Many scientific fields increasingly use high-performance computing (HPC) to process and analyze massive amounts of experimental data while storage systems in today’s HPC environments have to cope with new access patterns. These patterns include many metadata operations, small I/O requests, or randomized file I/O, while general-purpose parallel file systems have been optimized for sequential shared access to large files. Burst buffer file systems create a separate file system that applications can use to store temporary data. They aggregate node-local storage available within the compute nodes or use dedicated SSD clusters and offer a peak bandwidth higher than that of the backend parallel f…
Additional file 3: of Living alone and positive mental health: a systematic review
2019
Search strategies by database. This file presents the search strategies by each database employed in the study. (DOCX 35 kb)
Additional file 3: of Living alone and positive mental health: a systematic review
2019
Search strategies by database. This file presents the search strategies by each database employed in the study. (DOCX 35 kb)
GIAO/DFT 13C NMR Chemical Shifts of 1,3,4-Thiadiazoles
2007
1 H, 13 C and 15 N NMR spectra of 2-acetylamino-1,3,4-thiadiazole and its 5-substituted derivatives have been measured and assigned based on reference data, as well as homo- and heteronuclear 2 D NMR experiments. In addition, the GIAO/DFT approach at the B3LYP level of theory using the 6-311G basis set was used to calculate the 13 C NMR chemical shifts. Although this method gives reliable results for 2-arylhydrazones of 1,3-diphenylpropanetrione, 2-phenacylpyridines, (Z)-2-(2-hydroxy-2-phenylvinyl)pyridines, 4-fluoroanilines, (1Z,3Z)-1,4-di(pyridin-2-yl)buta-1,3-dienediols and their tautomeric forms, the calculated chemical shifts for the 1,3,4-thiadiazoles studied are less satisfactory. Pr…
Thiophen—Mangantricarbonyl-Komplexe
1967
Abstract Cationic thiophenemanganese tricabonyl complexes of the formula [C 4 (CH 3 ) x H 4- x S Mn(CO) 3 ] + have been prepared with 2-methyl-, 3-methyl-, 2,5-dimethyl-, 2,3,5-trimethyl-, tetramethylthiophene, and with thiophene by the reaction of Mn(CO) 5 Cl+AlCl 3 or AlBr 3 with the thiophenes in petrol ether, at 100–110°. The complexions give yellow solutions which are fairly stable. Their IR and some NMR spectra are given and discussed.