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Extracting Semantics of Individual Places from Movement Data by Analyzing Temporal Patterns of Visits
Data reflecting movements of people, such as GPS or GSM tracks, can be a source of information about mobility behaviors and activities of people. Such information is required for various kinds of spatial planning in the public and business sectors. Movement data by themselves are semantically poor. Meaningful information can be derived by means of interactive visual analysis performed by a human expert; however, this is only possible for data about a small number of people. We suggest an approach that allows scaling to large datasets reflecting movements of numerous people. It includes extracting stops, clustering them for identifying personal places of interest (POIs), and creating temporal signatures of the POIs characterizing the temporal distribution of the stops with respect to the daily and weekly time cycles and the time line. The analyst can give meanings to selected POIs based on their temporal signatures (i.e., classify them as home, work, etc.), and then POIs with similar signatures can be classified automatically. We demonstrate the possibilities for interactive visual semantic analysis by example of GSM, GPS, and Twitter data. GPS data allow inferring richer semantic information, but temporal signatures alone may be insufficient for interpreting short stops. Twitter data are similar to GSM data but additionally contain message texts, which can help in place interpretation. We plan to develop an intelligent system that learns how to classify personal places and trips while a human analyst visually analyzes and semantically annotates selected subsets of movement data
Liquefaction Potential of the Hydrotechnical Dikes Foundation Ground
The complex hydrotechnical works achieved upon the lower basin of the Olt river, within the southern part of Romania, imposed the building of several large reservoirs situated within the geo-morphological unit of the above named river flood plane. During the last years, due to the recent earthquakes that affected Romania, the macro-earthquake zoning of the country was changed. In these conditions, the problem of studying the stability of dikes foundation ground from the liquefaction point of view has raised. The paper presents the survey done in site and laboratory tests performed in order to determine most accurately, the natural ground geotechnical and dynamic parameters as well as an original method in order to estimate the ground liquefaction potential. Finally, the general stability analyses of the assembled dike-foundation ground is presented in pseudo-static hypothesis with taking into account the geotechnical parameters expected in dynamic conditions
Effects of chromium supplementation on growth, nutrient digestibility and meat quality of growing pigs
The aim of the study was to evaluate the effects of chromium picolinate (CrPic) on growth performance, nutrient digestibility, and protein and lipid quality of five anatomical parts in growing pigs. The 30-day study was conducted on eight castrated Topigs growing male pigs, with an initial bodyweight of 17.16 ± 0.62 kg. The pigs were assigned to two groups (C, E), housed in individual metabolic cages, and fed on conventional diets with 17.80% crude protein (CP) and 3078 kcal/kg metabolizable energy (ME). The diet of E was supplemented with 200 ppm CrPic. Samples of ingesta and faeces were collected in three balance periods of five days each. At the end of the experiment, blood samples were collected, all pigs were slaughtered, and meat (tenderloin, loin, ham, shoulder, and belly) samples were collected. No significant differences of productive or plasma parameters were noticed. The results of the balance study showed that CrPic did not influence the digestibility of nitrogen, but the digestibility of fat was significantly decreased for group E. The nutritional quality of the collected samples was evaluated for proximate analysis. The tenderloin and ham samples had increased protein concentrations compared with C group. For belly and ham, the fat concentrations decreased significantly. As a result of this observation, amino acids and fatty acid profiles were analysed and a significant improvement were determined for E regarding essential amino acids. The conclusion of the study was that CrPic had positive effects on protein and fat metabolism and the meat had functional food attributes.Keywords: Amino acids, biochemical profile, chromium picolinate, digestibility, fatty acids, por
A brief review on micro-implants and their use in orthodontics and dentofacial orthopaedics
The aim of this study was to review the literature and evaluate the failure rates and factors that affect the stability and success of temporary anchorage devices (TADs) used as orthodontic anchorage. Data was collected from electronic databases: MEDLINE database and Google Scholar. Four combinations of term were used as keywords: \u201cmicro-implant\u201d, \u201cmini-implant\u201d, \u201cmini-screw\u201d, and \u201corthodontics\u201d. The following selection criteria were used to select appropriate articles: articles on implants and screws used as orthodontic anchorage, published in English, with both prospective and retrospective clinical and experimental investigations. The search provided 209 abstracts about TADs used as anchorage. After reading and applying the selection criteria, 66 articles were included in the study. The data obtained were divided into two topics: which factors affected TAD success rate and to what degree and in how many articles they were quoted. Clinical factors were divided into three main groups: patient-related, implant related, and management-related factors. Although all articles included in this meta-analysis reported success rates of greater than 80 percent, the factors determining success rates were inconsistent between the studies analyzed and this made conclusions difficult
Interaction with Nearly Environment and Old Structure for a Deep Excavation. Case History in Bucharest
The paper presents the influence of a deep excavation performed in Bucharest on the adjacent ground and on some old buildings around it; the damages and effects appeared during the excavation and the remedial measures are presented in detail, too. The excavation was designed to be 16.15 meters deep, sustained by a slurry wall enclosure of 60 cm thickness and pre-stressed anchors, and steel struts. Due to an accident that occured to the trench walls, a thorough monitoring by instrumentation started. The results of this monitoring are shown
Towards a Protocol for the Collection of VGI Vector Data
A protocol for the collection of vector data in Volunteered Geographic Information (VGI) projects is proposed. VGI is a source of crowdsourced geographic data and information which is comparable, and in some cases better, than equivalent data from National Mapping Agencies (NMAs) and Commercial Surveying Companies (CSC). However, there are many differences in how NMAs and CSC collect, analyse, manage and distribute geographic information to that of VGI projects. NMAs and CSC make use of robust and standardised data collection protocols whilst VGI projects often provide guidelines rather than rigorous data collection specifications. The proposed protocol addresses formalising the collection and creation of vector data in VGI projects in three principal ways: by manual vectorisation; field survey; and reuse of existing data sources. This protocol is intended to be generic rather than being linked to any specific VGI project. We believe that this is the first protocol for VGI vector data collection that has been formally described in the literature. Consequently, this paper shall serve as a starting point for on-going development and refinement of the protocol
Tribological characterisation of magnetron sputtered Ti(C, O, N) thin films
Ti(C, O, N) thin films were prepared by magnetron sputtering and analysed in terms of their tribological properties. Surface and tribological parameters were analysed and discussed as a function of the films composition and structural features, as well as their thickness. The evolution of friction coefficient values was in concordance with the wear behaviour of the films. According to the atomic composition of the films, an increasing of the carbon percentage and a compound chemical formula closed to the stoichiometric TiC lead to a very good wear behaviour. This aspect is also directly correlated with the friction behaviour.Fundação para a Ciência e Tecnologia (FCT) SFRH/BPD/27114/2006 e PTDC/CTM/69362/200
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