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Peri-Urban Transformations in Agricultural Landscapes of Perugia, Italy  [PDF]
Marco Vizzari
Journal of Geographic Information System (JGIS) , 2011, DOI: 10.4236/jgis.2011.32011
Abstract: Urban fringes represent very complex landscapes because of their proximity and mutual dependency with cities and rural areas. These landscapes may be considered as transition entities characterized by fuzzy boundaries. An uncontrolled development of urban sprawl and land use changes in these areas may deter- mine negative impacts on all natural, economic and social components. Thus, urban fringes assume a key-role in modern landscape analysis, planning and management. Landscape analysis of these interfaces, as this study shows, can be effectively supported by GIS spatial modelling. The Settlement Density Index (SDI), developed through GIS spatial analysis techniques, expresses punctually the territorial gradients generated by the presence of settlements and allows the identification of the urban fringes in the two periods under invest-tigation. These areas are then characterized and analyzed quantitatively using detailed land use data. The comparison of the diachronic information highlights the transformations of peri-urban landscapes that appear mainly related to the modifications of spatial configuration of urban areas and to the changes of agricultural systems.
Multiple Lorentz Groups—A Toy Model for Superluminal Muon Neutrinos  [PDF]
Marco Schreck
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.310177
Abstract: In this article an idea is presented, which allows for the explanation of superluminal muon neutrinos. It is based on the introduction of a new superluminal, massless gauge boson coupling to the neutrino only, but not to other standard model particles. The model is discussed with regard to the Supernova 1987 (SN 1987) velocity bound on electron antineutrinos and the Cohen-Glashow constraint on superluminal neutrino propagation. The latter can be circumvented if— within the framework of the model—a sterile neutrino mixing with the active neutrino mass eigenstates is introduced. The suggestion of a sterile neutrino accounting for superluminal neutrinos has already been proposed in several papers. It is possible to choose mixing angles with the sterile neutrino sector such that the model respects both the SN 1987 bound and the muon neutrino travels superluminally.
Concept for Floating and Submersible Wireless Sensor Network for Water Basin Monitoring  [PDF]
Marco Allegretti
Wireless Sensor Network (WSN) , 2014, DOI: 10.4236/wsn.2014.66011
Abstract:
It will show the feasibility of a Wireless Sensor Network (WSN) devoted to monitoring water basin, river, lake, and sea both on the surface and in depth. The swarm of floating probes can be programmed to periodically sink some tens of meters below the surface, collecting data, characterizing water properties and then coming to the surface again. The life span of the probes may be assured by an on-board power supply or through batteries recharged by solar cells. The basic idea of the WSN is reported together with a detailed analysis of the operational constraints, the energy requirements, and the electronic and mechanical discussion.
Considerations on Mechanism Designs as Suitable for Cultural Heritage Evaluation  [PDF]
Marco Ceccarelli
Advances in Historical Studies (AHS) , 2013, DOI: 10.4236/ahs.2013.24022
Abstract: Technological developments can be considered part of Cultural Heritage that deserves to be preserved for historical records and memories to a large public. Such a preservation can be also useful from technical viewpoints both to track past evolutions and to understand future trends. In this paper both designs and approaches for mechanism design are illustrated as worthy of being considered elements of Cultural Heritage with both above mentioned values mainly but not only for engineers. Examples of mechanism inventions and design algorithms both for whole machines and mechanism components are reported to show how technical achievements are and can be considered for Cultural Heritage in a broad sense and application, not only for technical use.
Fragility Curves of Existing RC Buildings Based on Specific Structural Performance Levels  [PDF]
Marco Vona
Open Journal of Civil Engineering (OJCE) , 2014, DOI: 10.4236/ojce.2014.42011
Abstract: In seismic risk mitigation policies, fragility functions of existing buildings play a fundamental role. In this paper, a procedure to develop analytical fragility curves for Moment Resisting Frame Reinforced Concrete buildings is presented. The design of the selected building typologies was performed according to the codes at the time of construction using force-based methods and the state of the practice at the time of construction. A total of 216 building classes were defined, considering different ages, number of storeys, infill panels, plan dimensions, beam stiffness, and concrete strength. The investigated buildings can be considered low-engineered buildings, using no seismic codes or old seismic codes. The seismic capacity of the selected models representing the existing RC buildings has been evaluated through non-linear dynamic simulations. Seismic response has been analyzed, considering various peak and integral intensity measures and various response parameters, such as ductility demands and Interstorey Drift Ratio (IDR). A new relationship among structural performance, damage levels and interstorey drift ratios for each studied type is introduced, which is calibrated using the damage levels described in EMS98. It is important to highlight that in this study, different thresholds of IDR have been associated with different typologies, considering their different ductility member levels after their different structural responses. Fragility Curves (FCs) for the studied structural types are set up, developed and discussed.
A Software Package Generating Long Term and Near Real Time Predictions of the Critical Frequencies of the F2 Layer over Europe and Its Applications  [PDF]
Marco Pietrella
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.64029
Abstract: Long term prediction and near real time (nowcasting) maps of the critical frequency of the F2 layer (foF2), over the geographic area extending in latitude from 34°N to 60°N and in longitude from -5°W to 40°E, have been provided since 2006 by the DIAS (European Digital Upper Atmosphere Server) system. This work describes the software package PRODUCTION_DATABASE_foF2 & Extract_Real_Time_Grid_foF2 constituted by two original software packages called PRODUCTION_ DATABASE_foF2 and Extract_Real_Time_Grid_foF2 which have been developed in the framework of the ESA SSA Programme P2-SWE-1, in order to provide numerical grids of foF2 prediction on a mapping area more extended than that offered by the DIAS both in latitude (from 34°N to 80°N) and in longitude (from -10
Embedding Authentication & Authorization in Discovery Protocols for Standard Based Publish/Subscribe Middleware: A Performance Evaluation  [PDF]
Fabrizio Ronci, Marco Listanti
Communications and Network (CN) , 2011, DOI: 10.4236/cn.2011.31006
Abstract: Standard based Pub/Sub middleware, such as OMG Data Distribution Service (DDS), could assume a key role in supporting computer communications requiring continuous state information updating, deterministic deadline to data delivering and real time information adjourning. This kind of capability could be well ex-ploited by Peer-To-Peer (P2P) systems, Internet-wide as long as private ones, like in Public Safety or Civil Protection Communication Systems; but Pub/Sub specifications, and DDS/RTPS (Real Time Publish Sub-scribe) as well, usually do not provide Authentication & Authorization (AA) mechanisms. In the present work two important novelties are assessed: a possible scheme to implement AA in DDS/RTPS networks and a time performance evaluation study about embedded Authentication in RTPS.
Self-Play and Using an Expert to Learn to Play Backgammon with Temporal Difference Learning  [PDF]
Marco A. Wiering
Journal of Intelligent Learning Systems and Applications (JILSA) , 2010, DOI: 10.4236/jilsa.2010.22009
Abstract: A promising approach to learn to play board games is to use reinforcement learning algorithms that can learn a game position evaluation function. In this paper we examine and compare three different methods for generating training games: 1) Learning by self-play, 2) Learning by playing against an expert program, and 3) Learning from viewing ex-perts play against each other. Although the third possibility generates high-quality games from the start compared to initial random games generated by self-play, the drawback is that the learning program is never allowed to test moves which it prefers. Since our expert program uses a similar evaluation function as the learning program, we also examine whether it is helpful to learn directly from the board evaluations given by the expert. We compared these methods using temporal difference methods with neural networks to learn the game of backgammon.
Measuring Salinity within Shallow Piezometers:Comparison of Two Field Methods  [PDF]
Enrico Balugani, Marco Antonellini
Journal of Water Resource and Protection (JWARP) , 2010, DOI: 10.4236/jwarp.2010.23029
Abstract: The objective of this study is to understand the validity of salinity vertical profiles collected from shallow piezometers that are not previously flushed. This study shows that salinity data collected from boreholes are only an average value along the entire screened section of the piezometer. In order to collect data that is rep-resentative for the salinity of the adjacent aquifer, a new monitoring strategy has been developed. This strat-egy includes measurement of the salinity at the top of the watertable in an auger hole which is a shallow boreholes made with an handheld drill. This should be combined with measurements in piezometers that are first flushed to take out stagnant water. From the piezometers on can measure the average salinity of the screened part and the salinity at the bottom of the aquifer. By using this monitoring strategy it is also possi-ble to define where the piezometers screens are located if this is not known beforehand.
Symmetry Restoration by Acceleration  [PDF]
Paolo Castorina, Marco Finocchiaro
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.311209
Abstract: The restoration of spontaneous symmetry breaking for a scalar field theory for an accelerated observer is discussed by the one-loop effective potential calculation and by considering the effective potential for composite operators. Above a critical acceleration, corresponding to the critical restoration temperature, Tc, for a Minkowski observer by Unruh relation, i.e. ac/2π=Tc, the symmetry is restored. This result confirms other recent calculations in effective field theories that symmetry restoration can occur for an observer with an acceleration larger than some critical value. From the physical point of view, a constant acceleration mimics a gravitational field and the critical acceleration to restore the spontaneous symmetry breaking corresponds to a huge gravitational effect which prevents boson condensation.
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