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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.
Takashi Iida Ichiro Komatsubara Frederic C. Chang Junichi Goto Toshio Nambara 《Lipids》1990,25(11):753-755
Capillary gas-liquid chromatographic separation was studied for 60 oxo and oxo-hydroxy bile acids of theallo (5α-H, A/B-trans) and normal (5β-H, A/B-cis) series, which differ from one another in the number, position, and configuration of oxo and hydroxy groups at positions
C−3, C−4, C−6, C−7, and/or C−12. Good separation of the isomers was achieved by the use of an aluminum-clad fused-silica capillary
column coated with bonded and cross-linked methyl polysiloxane. 相似文献
53.
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
54.
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
55.
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
56.
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58.
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
59.
Fiber-coupling efficiency for free-space optical communication through atmospheric turbulence 总被引:3,自引:0,他引:3
High-speed free-space optical communication systems have recently used fiber-optic components. The received laser beam in such a system must be coupled into a single-mode fiber at the input of the receiver module. However, propagation through atmospheric turbulence degrades the spatial coherence of a laser beam and limits the fiber-coupling efficiency. We numerically evaluate the fiber-coupling efficiency for laser light distorted by atmospheric turbulence. We also investigate the use of a coherent fiber array as a receiver structure and find that a coherent fiber array that consists of seven subapertures would significantly increase the fiber-coupling efficiency. 相似文献
60.
Reviews and evaluates school consultation research conducted during the past decade. Attention is given to the breadth and quality of the present consultation knowledge base, the appropriateness of data analysis procedures, and the impact of consultation research findings on consultation training. Recommendations for future directions in school consultation research are offered from both methodological and substantive perspectives. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献