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91.
92.
Paul Stollard 《Fire Safety Journal》1985,8(3):169-175
A system of analysing fire reports is described, which evaluates the success of failure of the building elements and occupants in mitigating the consequencies of ignition. To handle fire reports a method of categorising the fire growth sequence in terms of both flame and smoke spread was developed. Three tactics (ignition prevention, fire control and evacuation) which mitigate the consequencies of ignition were derived from a hierarchy of fire safety and their interrelationship was examined. The application of this analysis method to two sets of the reports of fires in health buildings was undertaken and its success validated the proposed methodology. 相似文献
93.
Paul W. Angel Chandra S. Ray Delbert E. Day 《Journal of the American Ceramic Society》1986,69(6):134-C
94.
Paul M. Hurst 《Accident; analysis and prevention》1980,12(4):259-266
Research findings in other countries suggest that drinking driving laws could be much better enforced even without resorting to special patrols or random checks. It has been reported that law enforcement officers apprehend or breath test only a small fraction of the potentially impaired drivers that they normally encounter on patrol. This survey of New Zealand traffic officers was designed to determine the extent to which this was the case here, and what were the major disincentives to breath testing. Traffic officer responses, obtained on an anonymous questionnaire, suggested that there were not so many missed opportunities as had been suggested by others, but that there was a great deal of variability in the number of drinking drivers detected by different officers. This was confirmed by the actual distribution of breath testing activity, which was markedly different in shape (positively skewed) compared to the distribution of traffic enforcement activities in general. Several clues from the disincentives cited on the questionaire suggested that there are major deterrents to a greater degree of alcohol enforcement activity on the part of most officers. These are discussed in terms of potential legislative changes, and in relation to the changes introduced in the 1978 Transport Act Amendment. 相似文献
95.
Phillips Dorothy A.; Hearty Paul J.; Latrémouille Susane; Treurniet William C.; Whalen Thomas E. 《Canadian Metallurgical Quarterly》1985,26(3):219
Discusses telematics, a new field of behavioral research in Canada that has grown with the technical developments in which computers and telecommunications have been combined. Three domains of behavioral research reflect relationships between humans and the technology and use the evidence and methods of different areas of psychology: (1) interface studies address perception and performance questions, (2) dialog studies focus on cognitive processes, and (3) impact studies investigate social relations and how institutions and individuals are affected by telematics. Studies conducted during the past 5 yrs by the Behavioural Research and Evaluation division of the Department of Communications, Government of Canada, are described in each of these 3 domains. Behavioral research in telematics is expected to be an increasingly important activity in which psychologists may play an active part as the technology disseminates. (French abstract) (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Bisphenol A polycarbonate is shown to be miscible with a vinylidene chloride based polymer containing 13.5% by weight of vinyl chloride. On the other hand, polycarbonate is found to be immiscible with poly(vinyl chloride), poly(vinylidene fluoride), and polyepichlorohydrin. 相似文献
97.
Control over crystallographic orientation in ceramic thin films is important for highly anisotropic structures. Layered perovskites, like Bi4 Ti3 O12 , have interesting properties associated with their ferroelectric nature, which may be fully exploited only when films are highly textured. Textured films of this titanate were fabricated via a sol–gel technique without using epitaxial growth. Orientation in the film is confirmed by XRD and SEM, and supported by refractive index and dielectric measurements. In an attempt to explain the orienting effect, light scattering experiments were conducted to yield information about the molecular size, shape, and conformation of macromolecules as the sol–gel solution ages and condensation reactions proceed. These experiments clearly show an increase in the size of molecular clusters with time. We believe that it is the organization of these large clusters during spin coating, and the relationship of the backbone chemistry to the crystal structure of Bi4 Ti3 O12 , that are responsible for the observed orientation. 相似文献
98.
The phase behavior of ternary blends of tetramethyl polycarbonate (TMPC), polycarbonate (PC), and styrenic polymers has been examined by experiment and analyzed in terms of thermodynamic theories. The phase boundaries were predicted using both the modified Flory-Huggins theory and the lattice fluid theory. The boundaries predicted using the lattice fluid theory agree best with the experimental results. The experimental phase behavior of ternary blends was compared with binary blends having exactly the same chemical components and compositions except that the TMPC and PC units were present in the form of a copolycarbonate in the binary. The miscible region of these ternary blends is much narrower than that of the corresponding binary blends, even though the entropic and energetic terms of such ternary blends are more favorable than those of the binary blends. It is shown that a negative value of noncombinatorial free energy in multicomponent systems is not a sufficient condition for miscibility, because of asymmetries of mer-mer interactions. A comparison of the stability conditions for these binary and ternary blends shows that increasing the degrees of freedom tends to destabilize the mixture. 相似文献
99.
Kallie Christopher S.; Schrater Paul R.; Legge Gordon E. 《Canadian Metallurgical Quarterly》2007,33(1):183
Walking without vision results in veering, an inability to maintain a straight path that has important consequences for blind pedestrians. In this study, the authors addressed whether the source of veering in the absence of visual and auditory feedback is better attributed to errors in perceptual encoding or undetected motor error. Three experiments had the following results: No significant differences in the shapes of veering trajectories were found between blind and blindfolded participants; accuracy in detecting curved walking paths was not correlated with simple measures of veering behavior; and explicit perceptual cues to initial walking direction did not reduce veering. The authors present a model that accounts for the major characteristics of participants' veering behavior by postulating 3 independent sources of undetected motor error: initial orientation, consistent biases in step direction, and, most important, variable error in individual steps. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Vaporization of alloying elements is a serious problem in the laser welding of many important engineering alloys. Since the
available mass transfer correlations are not applicable for credible assessment of the rates of transport of vaporized species
in the gas phase, the role of gas phase mass transfer in the overall vaporization of alloying elements was examined by conducting
several critical experiments. The rates of transport of alloying elements in the weld pool were determined from numerically
computed fluid flow fields. Since the weld pool is surrounded by plasma during laser welding, the role of plasma in the vaporization
of alloying elements was physically modeled by allowing molten copper drops to vaporize isothermally both in the presence
and absence of plasma. The transport of alloying elements in both liquid and gas phases was found to be rapid and the overall
vaporization rates were controlled by the plasma influenced intrinsic vaporization of alloying elements at the weld pool surface.
The experimentally obtained rates of vaporization of alloying elements from laser melted stainless steel weld pools were compared
with the corresponding theoretically calculated values. 相似文献