Search results for "load"
showing 10 items of 1967 documents
Study and Simulation of Helicopter Gearboxes Noise
2010
International audience; Main gearbox is one of the main noise sources in helicopter cabin. In order to improve the comfort of customers and reduce the health impact, acoustic and vibration mechanisms of gearboxes have to be understood and simulated during development phases. Thus, we first present the global methodology chosen to compute main gearboxes noise in helicopter cabins. Secondly, we described the way we compute mechanical excitation sources induced from gear mesh, static transmission error and meshing stiffness. Depending on the type of gear, we compute those using either analytical specially developed code or EC codes. Thirdly, we propose a modeling to compute dynamic loads on be…
Synthesis and Structure Elucidation of Novel Spirooxindole Linked to Ferrocene and Triazole Systems via [3 + 2] Cycloaddition Reaction
2022
In the present work, a novel heterocyclic hybrid of a spirooxindole system was synthesized via the attachment of ferrocene and triazole motifs into an azomethine ylide by [3 + 2] cycloaddition reaction protocol. The X-ray structure of the heterocyclic hybrid (1″R,2″S,3R)-2″-(1-(3-chloro-4-fluorophenyl)-5-methyl-1H-1,2,3-triazole-4-carbonyl)-5-methyl-1″-(ferrocin-2-yl)-1″,2″,5″,6″,7″,7a″-hexahydrospiro[indoline-3,3″-pyrrolizin]-2-one revealed very well the expected structure, by using different analytical tools (FTIR and NMR spectroscopy). It crystallized in the triclinic-crystal system and the P-1-space group. The unit cell p…
On the structural optimization in presence of base isolating devices
2012
The minimum volume design of plane frames constituted by elastic perfectly plastic material and subjected to appropriate combinations of fixed, cyclic and dynamic loads is studied. The influence on the design, in terms of cost (volume) and behavioural features, of seismic protecting devices is particularly focused. The considered protecting device is a lead rubber bearing base isolation system. Two optimal design problem formulations are proposed for the structure with or without the protecting device, both based on the so-called statical approach. The minimum volume frame is reached accounting for three different resistance limits: the purely elastic limit, the (elastic) shakedown limit an…
Autorreflexión pedagógica
2019
The autobiographical reflection on school learning makes it possible to explain how personal life guidelines are loading teaching activity with experiences. Educational time does not consist only of a linear narration, but works as the evocation of temporal and spatial memories of an explanation of the present. Personal life is intertwined with school reflection to give meaning to what we decide from teaching
Monitoring Training and Recovery during a Period of Increased Intensity or Volume in Recreational Endurance Athletes
2021
The purpose of the study was to examine the effects of progressively increased training intensity or volume on the nocturnal heart rate (HR) and heart rate variability (HRV), countermovement jump, perceived recovery, and heart rate-running speed index (HR-RS index). Another aim was to analyze how observed patterns during the training period in these monitoring variables were associated with the changes in endurance performance. Thirty recreationally trained participants performed a 10-week control period of regular training and a 10-week training period of either increased training intensity (INT, n = 13) or volume (VOL, n = 17). Changes in endurance performance were assessed by an incremen…
The Role of Surface Acting in the Relationship between Job Stressors, General Health and Need for Recovery Based on the Frequency of Interactions at …
2022
The aim of the study was to verify whether the frequency of face-to-face interactions with the public at work can reveal differences in how people react to emotional regulation demands. In particular, we investigated the mediating role of surface acting (a strategy of dealing with emotional dissonance) in the relationship between two typical job stressors (workload and mental load) and two outcomes closely related to work-related well-being: employees’ general health and the need for recovery. Prior studies investigating the detrimental effects of emotional dissonance mostly focused on service workers. However, in light of a survey conducted by the European Agency for Safety and Health at W…
Post-exercise heart rate variability : a new approach to evaluation of exercise-induced physiological training load
2015
To improve maximal endurance performance, an optimal physiological training load, i.e. the balance between exercise and recovery, is required. In general, the goal of a single endurance exercise session is to transiently disturb body homeostasis after which a so-called supercompensation, an improvement in performance, can occur if the recovery period is adequate. The physical training load of a single exercise session consists of the combination of exercise intensity and duration. At the present time, there is no single tool to quantify the amount of disturbance of homeostasis that is equal to physiological training load of a single exercise session. Heart rate variability (HRV), the change…
Introduction of Multiflow for HSDPA
2012
This paper introduces a multi-cell transmission scheme for High-Speed Downlink Packet Access (HSDPA) networks, called Multiflow. In this concept, downlink data is transmitted to a user terminal at the border of two cells from one or both of the cells. The cells may belong to same NodeB or to two different NodeBs. The data flows are separated by different scrambling codes used by each associated cell, thus the flows can be treated independently. This provides increased multi-user diversity by means of flexibility in downlink resource management, in addition to the spatial diversity of multiple transmission locations. Another important gain mechanism for this scheme is realized by short-term …
Measuring Distraction at the Levels of Tactical and Strategic Control: The Limits of Capacity-Based Measures for Revealing Unsafe Visual Sampling Mod…
2011
The control theory of driving suggests that driver distraction can be analyzed as a breakdown of control at three levels. Common approach for analyzing distraction experimentally is to utilize capacity-based measures to assess distraction at the level of operational control. Three driving simulation experiments with 61 participants were organized to evaluate which kind of measures could be used to analyze drivers' tactical visual sampling models and the related effects of distraction while searching textual information on in-car display. The effects of two different text types were evaluated. The utilized capacity-based measures seemed to be insufficient for revealing participants' tactical…
High school students' perspective to university CS1
2013
This paper presents a qualitative study of a school-university collaborative project where a game-themed CS1 course was offered as-is to high school students. Our specific interest was to explore the students' experiences with the university level course. Our analyses indicate that immediate and regular support was highly important for student performance, as support of this kind could mitigate issues related to students' orientation towards the high workload of the course. Students who showed academic interest were likely to pass, whereas students lacking self-direction or work efficiency were likely to drop out. Both passed and drop-outs found the course to be a good learning experience. …