Search results for "lcsh:Technology"
showing 10 items of 550 documents
Sequential and joint hydrogeophysical inversion using a field-scale groundwater model with ERT and TDEM data
2013
Abstract. Increasingly, ground-based and airborne geophysical datasets are used to inform groundwater models. Recent research focuses on establishing coupling relationships between geophysical and groundwater parameters. To fully exploit such information, this paper presents and compares a joint hydrogeophysical inversion (JHI) approach and sequential hydrogeophysical inversion (SHI) approach to inform a field-scale groundwater model with Time Domain Electromagnetic (TDEM) and Electrical Resistivity Tomography (ERT) data. The implemented SHI coupled inverted geophysical models with groundwater parameters, where the strength of the coupling was based on geophysical parameter resolution. To t…
Discharge estimation combining flow routing and occasional measurements of velocity
2011
A new procedure is proposed for estimating river discharge hydrographs during flood events, using only water level data at a single gauged site, as well as 1-D shallow water modelling and occasional maximum surface flow velocity measurements. One-dimensional diffusive hydraulic model is used for routing the recorded stage hydrograph in the channel reach considering zero-diffusion downstream boundary condition. Based on synthetic tests concerning a broad prismatic channel, the “suitable” reach length is chosen in order to minimize the effect of the approximated downstream boundary condition on the estimation of the upstream discharge hydrograph. The Manning’s roughness coefficient is calibra…
Analysis of the energy balance closure over a FLUXNET boreal forest in Finland
2010
Abstract. The imbalance in the surface energy budget, when using eddy-covariance techniques to measure turbulent fluxes, is still an unresolved problem. Important progresses have been reported in recent years identifying potential reasons for this lack of energy balance closure. In this paper we focus on the data collected in a FLUXNET boreal forest site in Sodankylä, Finland. Using one month half-hourly data, an average Energy Balance Ratio (EBR) of 0.72 is obtained. The inclusion of the heat storage terms in the energy budget yields an improvement of about 6% in the total closure. The sensitivity of the energy balance closure to the turbulence intensity is analysed in terms of the frictio…
Mapping daily evapotranspiration at field to continental scales using geostationary and polar orbiting satellite imagery
2011
Abstract. Thermal infrared (TIR) remote sensing of land-surface temperature (LST) provides valuable information about the sub-surface moisture status required for estimating evapotranspiration (ET) and detecting the onset and severity of drought. While empirical indices measuring anomalies in LST and vegetation amount (e.g., as quantified by the Normalized Difference Vegetation Index; NDVI) have demonstrated utility in monitoring ET and drought conditions over large areas, they may provide ambiguous results when other factors (e.g., air temperature, advection) are affecting plant functioning. A more physically based interpretation of LST and NDVI and their relationship to sub-surface moistu…
Sustainable vehicle routing based on firefly algorithm and TOPSIS methodology
2019
Abstract In a sustainable management of logistics, transportation plays a crucial role. Traditionally, the main purpose was to solve the Vehicle Routing Problem minimizing the cost associated with the travelled distances. Nowadays, the economic profit cannot be the only driver for achieving sustainability and environmental issues have to be also considered. In this paper, to satisfy the intricate limits involved in real vehicle routing problem, the study has been structured considering different types of vehicles in terms of maximum capacity, velocity and emissions, asymmetric paths, vehicle-client constraints and delivery time windows. The firefly algorithm has been implemented to solve th…
Computation of vertically averaged velocities in irregular sections of straight channels
2015
Abstract. Two new methods for vertically averaged velocity computation are presented, validated and compared with other available formulas. The first method derives from the well-known Huthoff algorithm, which is first shown to be dependent on the way the river cross section is discretized into several subsections. The second method assumes the vertically averaged longitudinal velocity to be a function only of the friction factor and of the so-called "local hydraulic radius", computed as the ratio between the integral of the elementary areas around a given vertical and the integral of the elementary solid boundaries around the same vertical. Both integrals are weighted with a linear shape f…
Transgenic Killer Commensal Bacteria as Mucosal Protectants
2001
As first line of defense against the majority of infections and primary site for their transmission, mucosal surfaces of the oral cavity and genitourinary, gastrointestinal, and respiratory tracts represent the most suitable sites to deliver protective agents for the prevention of infectious diseases. Mucosal protection is important not only for life threatening diseases but also for opportunistic infections which currently represent a serious burden in terms of morbidity, mortality, and cost of cures. Candida albicans is among the most prevalent causes of mucosal infections not only in immuno- compromised patients, such as HIV-infected subjects who are frequently affected by oral and esoph…
Alternativas para reflexionar aspectos críticos de la ciencia en el aula
2015
Este artículo forma parte de una investigación sobre el uso de cuestiones socio-científicas a fin de promover las competencias para el pensamiento crítico en estudiantes universitarios. La primera parte presenta las apreciaciones de un grupo de estudiantes en formación docente acerca de la criticidad de la ciencia y lo que entienden por ciencia crítica. También, se presenta y se discute sobre las experiencias de algunos investigadores perseguidos debido a sus contribuciones científicas, ya que tuvieron implicaciones sociales, o cuestiones sociocientíficas. Alternatives to Reflect on Critical Aspects of Science in the Classroom This paper is part of a research about the use of scientific-soc…
Virtual Reality and Games
2018
The concept of Virtual Reality (VR) dates back to around 1930, where different technologies and concepts arise. For instance, in 1929 Edward Link created the Link Trainer (further patented in 1931), reported to be the first example of a commercial flight simulator, being entirely electromechanical. Also, in the 1930s, the visionary, science fiction writer Stanley G. Weinbaum brings a story (Pygmalion’s Spectacles) that introduces the early idea of a pair of goggles that makes the wearer experience a fictional world through holograms, smell, taste, and touch. Weinbaum describes uncanny experiences for those wearing the goggles, aligned with the modern experiences of VR. It is in the mid 1950…
Automated PCB Inspection System
2017
TEM Journal; Vol 6, No 2, 2017. ISSN 2217-8309