Search results for "Rail"
showing 10 items of 699 documents
The role of prognostic stratification on prescription of anticoagulants in older patients with atrial fibrillation : a multicenter, observational, pr…
2022
Background: Literature suggests that different risks of mortality could influence physicians in prescribing or not anticoagulants in older patients with atrial fibrillation (AF). The Multidimensional Prognostic Index (MPI) can be considered a tool for the detection of multidimensional frailty. The aim of this cross-sectional study was to evaluate whether prescription patterns of oral anticoagulants exist, based on MPI values. Methods: Older hospitalised patients (age >= 65 years) with non-valvular AF were included across 24 European centres. MPI was calculated using validated and standardised tools derived from a comprehensive geriatric assessment. Other functional and clinical information …
Rail freight transport and demand requirements : an analysis of attribute cut-offs through a stated preference experiment
2014
This paper analyses the choice between road and rail in Spain where rail market share for freight is still residual. Discrete choice models are estimated with data obtained through a two-phase fieldwork, thus allowing us to carry out a stated preference efficient design for each interviewee. We analyse the existence of attribute cut-offs and the presence of a segment of the population with a zero value of frequency. Our results show that ignoring the existence of cut-offs and segments of the population with polarised valuations can lead to erroneous conclusions in terms of the possibilities of rail for absorbing significant quota.
Frailty and emergency surgery in the elderly: protocol of a prospective, multicenter study in Italy for evaluating perioperative outcome (The FRAILES…
2018
Improvements in living conditions and progress in medical management have resulted in better quality of life and longer life expectancy. Therefore, the number of older people undergoing surgery is increasing. Frailty is often described as a syndrome in aged patients where there is augmented vulnerability due to progressive loss of functional reserves. Studies suggest that frailty predisposes elderly to worsening outcome after surgery. Since emergency surgery is associated with higher mortality rates, it is paramount to have an accurate stratification of surgical risk in such patients. The aim of our study is to characterize the clinicopathological findings, management, and short-term outcom…
Transcutaneous transfer energy system designing for electronic pills
2015
Abstract This paper proposes a system capable of transcutaneous electric power delivery by means of a non-guided electromagnetic field, suitable for electronic pill technology to be continually powered without the limitations imposed by batteries. This system consists of a Class-E power oscillator, with a crystal-based feedback network to compensate automatically for changes in the operational frequency, multi-turn spiral coupled coils and a power recovery circuit providing a stable output voltage. The synthesis procedure is based on designing equations for optimizing the link efficiency. The proposed transcutaneous transfer energy system aims at transferring 100 mW and providing a stable 3…
A new mathematical function for describing electrophoretic peaks.
2005
A new model is proposed for characterizing skewed electrophoretic peaks, which is a combination of leading and trailing edge functions, empirically modified to get a rapid recovery of the baseline. The peak model is a sum of square roots and is called thereby "combined square roots (CSR) model". The flexibility of the model was checked on theoretical and experimental peaks with asymmetries in the range of 0-10 (expressed as the ratio of the distance between the center and the trailing edge, and the center and the leading edge of the chromatographic peak, measured at 10% of peak height). Excellent fits were found in all cases. The new model was compared with other three models that have show…
Experimental analysis of a thermoactive underground railway station
2022
Little is known about the real energy potential of thermoactive underground infrastructures, such as railway stations, that can act as a heating/cooling provider for the built environment. This study presents the results of thermomechanical full-scale in situ testing and numerical analysis of a thermoactive underground train station. The thermal performance and related geostructural impact of a portion of the new underground energy infrastructure (UEI) installed at the Lancy-Bachet train station in Geneva (Switzerland) are analyzed. Heating and cooling tests simulating real operative geothermal conditions are considered. Particular attention is given to ((i) the monitored wall-tunnel hydrot…
Increasing the Capacity of Existing Bridges by Using Unbonded Prestressing Technology: A Case Study
2014
External posttensioning or unbonded prestressing was found to be a powerful tool for retrofitting and for increasing the life extension of existing structures. Since the 1950s, this technique of reinforcement was applied with success to bridge structures in many countries, and was found to provide an efficient and economic solution for a wide range of bridge types and conditions. Unbonded prestressing is defined as a system in which the post-tensioning tendons or bars are located outside the concrete cross-section and the prestressing forces are transmitted to the girder through the end anchorages, deviators, or saddles. In response to the demand for a faster and more efficient transportati…
Adaptive Finite-Time Control for a Flexible Hypersonic Vehicle with Actuator Fault
2013
The problem of robust fault-tolerant tracking control is investigated. Simulation on the longitudinal model of a flexible air-breathing hypersonic vehicle (FAHV) with actuator faults and uncertainties is conducted. In order to guarantee that the velocity and altitude track their desired commands in finite time with the partial loss of actuator effectiveness, an adaptive fault-tolerant control strategy is presented based on practical finite-time sliding mode method. The adaptive update laws are used to estimate the upper bound of uncertainties and the minimum value of actuator efficiency factor. Finally, simulation results show that the proposed control strategy is effective in rejecting unc…
Network Arches: The World's Lightest Arch Bridges
2012
Summary Network arches have a tensile and a compressive flange with a web consisting of crossing hangers. Some of the hangers cross each other twice. The network can be seen as a very light, simply supported beam. There is little bending. There is a lot of tension in tie and hangers. The arches are well supported by hangers and wind bracing. Thus the buckling strength of the arch is high as long as few hangers relax. That is easiest to prevent when a concrete tie gives extra weight in the tie. The optimal shape of network arches is discussed. In two lane and two track network arches the biggest bending in the tie is usually the transverse bending half way between the arches. The optimal sha…
Applying complexity science to air traffic management
2015
Versión aceptada obtenida del archivo digital en línea WestminsterResearch de la Universidad de Westminster. Complexity science is the multidisciplinary study of complex systems. Its marked network orientation lends itself well to transport contexts. Key features of complexity science are introduced and defined, with a specific focus on the application to air traffic management. An overview of complex network theory is presented, with examples of its corresponding metrics and multiple scales. Complexity science is starting to make important contributions to performance assessment and system design: selected, applied air traffic management case studies are explored. The important contexts of…