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51.
This paper considers pre-impact vehicle maneuvers and analyzes the resulting driver motion from their comfort seating position. Part I of this work consists of analyzing the driver behavior during a crash. The study is conducted using the LAMIH driving simulator and involves 76 participants. The emergency situation is created by a truck emerging from behind a tractor on the opposite side of the road and tearing along the participant. The driver positioning throughout the simulation is recorded via five video cameras allowing view of the front scene, the driver face, feet and pedals, hands on the steering wheel and global lateral view. Data related to braking force, seat pressure, muscular activity for major groups of muscles and actions on the steering wheel are also collected.The typical response to this type of emergency event is to brace rearward into the seat and to straighten the arms against the steering wheel, or, to swerve to attempt to avoid the impacting vehicle. While turning the steering wheel, the forearm can be directly positioned on the airbag module at time of crash which represents a potential injurious situation.These positions are used in Part II to determine scenario of positions for numerical simulation of a frontal collision. 相似文献
52.
Avinash Hariharan Phil Goldberg Frederic Schell Ute Hempel Friedrich Striggow Martin Hantusch Mariana Medina-Sánchez Andrés F. Lasagni Annett Gebert 《Advanced functional materials》2024,34(8):2310607
This study explores the enhancement of biocompatible titanium-based implants through surface functionalization for improved bone healing. Specifically, a near-beta type Ti-13Nb-13Zr alloy is 3D printed using laser powder bed fusion and subsequently textured using nanosecond (ns) and picosecond (ps) direct laser interference patterning (DLIP) to create single-scale and multi-scale surface textures. On these textures, the cell behavior, morphology, metabolic activity and osteogenic differentiation potential of human bone marrow stromal cells are assessed using fluorescence microscopy and MTS assays. Moreover, tissue non-specific alkaline phosphatase activity served as an early osteoblast production marker. Compared to untextured specimens, both types of textures exhibited higher metabolic activity and cell proliferation. Single-scale ns-DLIP textures encouraged cell extensions anchored in groove regions, while ps-DLIP textures with hierarchical structures promoted cell extensions attaching to nanostructures on sidewalls. The groove width and nanotopographies in groove areas facilitated cell spreading. Surface topography, roughness, and surface chemistry (surface energy, wettability) influenced cell adhesion, proliferation, and differentiation. A comprehensive evaluation of DLIP-generated surface textures, including their topography and chemical states, complements the factors affecting in vitro cell behavior. Overall, this research demonstrates the potential of surface-functionalized 3Dprinted titanium for a novel generation of biocompatible implants. 相似文献
53.
Salowa Methnani Jean-Paul Gauthier Frederic Lafont 《International journal of control》2013,86(4):822-833
In this article, we propose a general methodology for identifying and reconstructing sensor faults on dynamical processes. This methodology is issued from the general identification theory developed in the previous papers (Busvelle, E., and Gauthier, J.-P. (2003), ‘On Determining Unknown Functions in Differential Systems, with an Application to Biological Reactor’, ESAIM: Control, Optimisation and Calculus of Variations, 9, 509–553; Busvelle, E., and Gauthier, J.-P. (2004), ‘New Results on Identifiability of Nonlinear Systems’, in 2nd Symposium on Systems, Structure and Control, Oaxaca, Mexico; Busvelle, E., and Gauthier, J.-P. (2005), ‘Observation and Identification Tools for Non Linear Systems. Application to a Fluid Catalytic Cracker’, International Journal of Control, 78, 208–234): in fact, this identification theory also provides a general framework for the problem of ‘observability with unknown inputs’. Indeed, many problems of fault detection can be formulated as such observability problems, the (eventually additive) faults being just considered as unknown inputs. Our application to ‘sensor fault detection’ for wastewater treatment plants (WWTP) constitutes an ideal academic context to apply the theory: first, in this 3-5 case (3 sensors, 5 states), the theory applies generically and, second, any system is naturally under the ‘observability canonical form’ required to apply the basic high-gain observer from Gauthier and Kupka (Gauthier, J.-P., and Kupka, I. (1994), ‘Observability and Observers for Nonlinear Systems’, SIAM Journal on Control, 32, 975–994). A simulation study on the Bleesbrük WWTP is proposed to show the effectiveness of this approach. 相似文献
54.
B Levy PF Perrigault P Gawalkiewicz F Sebire M Escriva P Colson D Wahl M Frederic PE Bollaert A Larcan 《Canadian Metallurgical Quarterly》1998,26(12):1991-1994
OBJECTIVE: To compare the influence of gastric and postpyloric enteral feeding on the gastric tonometric PCO2 gap (tonometric PCO2 - PaCO2). DESIGN: A prospective, clinical trial. SETTING: Two intensive care units in a university hospital. PATIENTS: Twenty patients undergoing mechanical ventilation and enteral feeding without catecholamines, sepsis, or sign of hypoxia. INTERVENTIONS: Patients were randomized to receive feeding through the tonometer (gastric group), or through a postpyloric tube (postpyloric group). MEASUREMENTS AND MAIN RESULTS: The patients received tube feeding at a rate of 50 mL/hr during 4 hrs. Baseline measurements included: mean arterial pressure, heart rate, tonometric parameters, arterial gases, and arterial lactate concentration. Except for lactate concentration, these measurements were repeated after 1 and 4 hrs of enteral feeding and 2 hrs after stopping enteral feeding. During the study, arterial pH and PaCO2 did not change. During enteral feeding, the PCO2 gap increased in the gastric group from a mean of 7+/-5 to 17+/-14 (SD) torr (0.9 0.7 to 2.3+/-1.9 kPa) (p< .O01) and did not change in the postpyloric group (5+/-5 to 3+/-1 torr [0.7+/-0.7 to 0.4+/-0.1 kPa]). Two hours after stopping enteral feeding, the PCO2 gap was still increased in the gastric group (15+/-9 vs. 7+/-5 torr [2.0+/-1.2 vs. 0.9+/-0.7 kPa]) (p < .01). CONCLUSION: The results indicate that gastric enteral feeding increased the PCO2 gap. However, postpyloric enteral feeding does not interact with gastric tonometric measurements and should be used when using gastric tonometry in enterally fed patients. 相似文献
55.
Henry Susan E.; Medway Frederic J.; Scarbro Harold A. 《Canadian Metallurgical Quarterly》1979,71(5):604
Gave 80 Black 1st graders varying in internal–external control (as identified by scores on the Stanford Preschool Internal–External Scale) a series of digit substitution problems during which their performance was praised by either a Black boy and girl or a Black man and woman ostensibly watching them from another room. Agents' feedback was previously videotaped. As predicted, boys were most responsive to peer feedback and girls were most responsive to adult feedback, as revealed by faster problem-solving rates on reinforced tasks, higher scores on a related substitution task, and greater attributions of agent helpfulness. Predictions involving locus of control received only modest support. The relationship of these results to earlier studies involving dissimilar populations is discussed and educational implications are drawn. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
A method for generating an impulse train or a binary signal (random telegraph waveform) with pseudorandom Poisson statistics is described. It uses the properties of the binomial distribution to approach the Poisson distribution in the limit. A simple digital-hardware implementation, based on this method, is presented, and some test results are given. 相似文献
57.
Developed 2 measures based on G. A. Kelly's Rep Grid Test, one dealing with personal events and the other with general societal events. Results from 258 undergraduates show that internals used significantly more internal constructs than did externals and that Ss chose more internal constructs on the personal than on the societal measure. Results suggest that the internal-external dichotomy is reflected in and may be mediated by modes of thinking and categorization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
59.
60.
Prof. Frederic G. Hammitt Ph. D. Prof. t. sc. Stefan Krzeczkowski Prof. Dr. habil. t. sc. Jerzy Krzyżanowski 《Forschung im Ingenieurwesen》1981,47(1):1-14
The state of art and ongoing research concerning the flow of wet steam in large steam turbines is reviewed, particularly from
the viewpoint of the behavior of the liquid film deposited upon the stationary blading. New experimental results concerning
the non-steady behavior of the film and the resultant wavelet formation patterns under the action of high-velocity low-pressure
steam flow are presented. These results are then correlated as a flow regime “map” showing various flow regions in terms of
steam velocity (or relative steam-film velocity since film velocity is relatively very small) vs. film flow rate per unit
transverse distance.
The distribution of liquid droplets shed from the blade trailing edge in the wake are studied as a function of distance downstream,
steam velocity, and liquid film flow rate. In addition the droplet size is correlated in terms of critical droplet Weber number
and compared with results of previous investigators. High-speed photographs of droplet distortions in a high-velocity air
stream are also included. 相似文献