Search results for "Time data"
showing 10 items of 15 documents
A distributed real-time data prediction and adaptive sensing approach for wireless sensor networks
2018
International audience; Many approaches have been proposed in the literature to reduce energy consumption in Wireless Sensor Networks (WSNs). Influenced by the fact that radio communication and sensing are considered to be the most energy consuming activities in such networks. Most of these approaches focused on either reducing the number of collected data using adaptive sampling techniques or on reducing the number of data transmitted over the network using prediction models. In this article, we propose a novel prediction-based data reduction method. furthermore, we combine it with an adaptive sampling rate technique, allowing us to significantly decrease energy consumption and extend the …
Atmospheric CO2 Concentrations in Caves Protected as Nature Reserves and Related Gas Hazard
2022
Atmospheric CO2 concentrations can reach high levels inside natural caves, representing a hazardous condition for both humans frequenting the underground environment and its safeguard due to the corrosion of speleothems induced by the acidification of atmospheric moisture. These issues are particularly critical for the eco-sustainable management of caves protected as nature reserves and undergoing touristic exploitation. In this paper we present the results of the C6 project, which was activated in 1999 for the monitoring of air quality inside three caves protected as nature reserves in Sicily (Italy). Near-real-time and spot measurements of air temperature and CO2 concentration have been c…
Determination of metal inventory and current efficiency in commercial aluminum reduction cells
1971
A method for the determination of the metal inventory in commercial aluminum reduction cells, based on radioisotope dilution, has been developed, employing a198Au tracer. By taking a large number of samples from the cells, the current efficiency is evaluated from the slope of the cumulative metal inventory vs time data. The method allows a determination of the current efficiency over a period of 2 to 3 days with a relative precision of approximately 1 pct. The paper gives a thorough discussion of the sources of error inherent in the procedure suggested.
Regression imputation for Space-Time datasets with missing values
2009
Data consisting in repeated observations on a series of fixed units are very common in different context like biological, environmental and social sciences, and different terminology is often used to indicate this kind of data: panel data, longitudinal data, time series-cross section data (TSCS), spatio-temporal data. Missing information are inevitable in longitudinal studies, and can produce biased estimates and loss of powers. The aim of this paper is to propose a new regression (single) imputation method that, considering the particular structure and characteristics of the data set, creates a “complete” data set that can be analyzed by any researcher on different occasions and using diff…
Leading indicator properties of US high-yield credit spreads.
2010
Abstract In this paper we examine the out-of-sample forecast performance of high-yield credit spreads for real-time and revised data regarding employment and industrial production in the US. We evaluate models using both a point forecast and a probability forecast exercise. Our main findings suggest that the best results come from using only a few factors obtained by pooling information from a number of sector-specific high-yield credit spreads. In particular, for employment and at short-run horizons, there is a gain from using a principal components model fitted to high-yield credit spreads compared to the prediction produced by benchmarks. Moreover, forecast results based on revised data …
Static and dynamic policies with RFID for the scheduling of retrieval and storage warehouse operations
2013
Warehouses are essential components of logistics and supply chains. The performance of warehouse operations significantly affects the efficiency of the whole chain it belongs to. Radio frequency identification (RFID) is an emerging technology capable of providing real-time information about the location and properties of tagged object(s), such as people, equipment or products. The objective of this article is threefold, to propose and compare different offline and online policies for the scheduling of warehouse operations, to design a tool that allows the decision maker to compare policies and environments without putting them into practice, and to study the benefits that can be obtained if…
Real-time weighting optimization in Chinese Postman Problem
2013
International audience; In this study, based on real-time constraint, an optimization method is proposed for solving the problem of the optimal tour. For that, we will construct a graph containing the real-time state of traffic. The collected data will be used to predict the future state traffic and to give an optimized cost of the tour. This optimization is tested in different sizes of the road networks. The results show that the proposed method is efficient and effective in solving the Chinese Postman Problem in real-time.
Modeling of a Smart Grid System Using Real Time Data οn Neplan
2013
The Institute for Energy and Transport (IET) is one of the seven institutes of the Joint Research Centre, which is a Directorate-General of the European Commission. IET is based both in Petten, the Netherlands, and Ispra, Italy, and has a multidisciplinary team of around three hundred academic, technical and support staff members. The mission of IET is to provide support to European Union policies in order to ensure sustainable, safe, secure and efficient energy production, distribution and use. The Energy Security Unit (ESU) is part of IET based in Petten and Ispra. A research action set up within this unit is devoted to studies on smart electricity systems (SES) and operates a Smart Grids…
Adaptīva lietotāja saskarne adrešu un plānotāja grāmatas Android lietotnes kontekstā
2019
Lietotāja saskarne ir tā, kas savieno lietotāju un lietojumprogrammu. Tas ir viens no vissvarīgākajiem aspektiem, kas rada lielu interesi par lietojumprogrammu. Daudzi dizaineri lietojumprogrammās piemēro adaptīvo lietotāja interfeisa (AUI) dizainu, lai lietotāji varētu justies laimīgi un apmierināti, lietojot programmu. Rakstā aprakstīta Android programmas, kas saucas Address&Planner Book, izstrāde, kurā var saglabāt svarīgus kontaktus un plānus un informēt lietotājus. Lietojumprogramma varētu pielāgot lietotāja saskarņu saturu un dizainu atbilstoši kontekstam, kas saistīts ar katru lietotāju, lai paredzētu lietotāja darbības un piedāvātu ērtu lietošanu. Programma ir izstrādāta, izmantojot…
The Correlation between Adolescent Daily Breakfast Consumption and Socio-Demographic:Trends in 23 European Countries Participating in the Health Beha…
2023
Breakfast is often considered the most important meal of the day and can benefit adolescent health in several ways. The aims of the present study were (1) to identify adolescents’ socio-demographic (sex, family affluence and family structure) determinants of daily breakfast consumption (DBC) and (2) to describe trends in DBC among adolescents across 23 countries. Cross-sectional surveys of nationally representative samples of adolescents (aged 11, 13, and 15 years) (n = 589,737) participating in the Health Behaviour in School-aged Children (HBSC) survey from 2002 to 2018 were used. Multilevel logistic regression analyses modeled DBC over time, adjusted for family affluence, family structure…