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71.
Capelli-Schellpfeffer M. Floyd H.L. II Eastwood K. Liggett D.P. 《Industry Applications Magazine, IEEE》2000,6(3):16-23
Using a corporate case study with data analysis, this article provides an example of how one company recognized the limitations of available electrical accident data and implemented a process for collecting information to support the improvement of the organizational culture and management systems around electrical safety. The business, manufacturing, engineering, behavioral safety, and regulatory compliance implications of the findings are discussed. Limitations in national and industrial electrical accident and fatality data are reviewed. Finally, future research directions are considered 相似文献
72.
Experience of vascular thrombosis prophylaxis and treatment after reconstructive operation conduction on abdominal aorta and peripheral arteries in 244 patients, including 112 of them immediately after the operation, 32-up to one year time, 100-in long-term follow-up period was summarized. Main aetiological cause for thrombosis occurrence immediately after the operation were technical and tactical failures committed during its conduction, in the early postoperative period-the neointima hyperplasia in the anastomosis area, in late terms-the blood outflow disorder from the reconstructed segment due to the atherosclerosis progression. Original methods of reoperation conduction for the transplant thrombosis and the outflow arteries reconstruction were proposed. Mortality lowering from 8.8 to 5.3% and the extremity revascularization occurrence, in 75% of patients immediately after the operation and in 84%-in long-term period was promoted owing to tactics of postoperative thrombosis treatment elaborated. 相似文献
73.
In order to successfully seam HDPE flexible membrane liners (FMLs) in cold weather (less than 4·5°C (40°F), FML temperature may not be the most important factor. Secondary cold weather effects such as frozen subgrade, bridging, snow and ice removal, and worker discomfort pose a much more significant risk to the integrity of the liner installation. 相似文献
74.
Neutral-atom recombination lasers in the vaporized plasmas of 28 different elements are reported. The results, which are consistent with the predictions of a simple model of a plasma-recombination laser, demonstrate the wide applicability of CO2 laser-produced plasmas as sources for laser excitation. 相似文献
75.
An integrated, intelligent design environment was designed and implemented. The heart of the environment is a userfriendly, menu-driven CAD system integrated with an information controller. The system allows the engineer to design in a feature-based, object-oriented manner. Designs are stored in a data base and checked for manufacturability and assembly by an expert system. This paper describes the design of the information integration controller and the man-machine interfaces of the intelligent design system. 相似文献
76.
In Situ Measurement of Nonlinear Shear Modulus of Silty Soil 总被引:1,自引:0,他引:1
A new field test method to evaluate in situ nonlinear shear modulus of soils was developed. The method utilizes a drilled shaft as a cylindrical, axisymmetric source for shear loading of soil at depth. The applicability of the test method was studied by conducting small-scale, prototype experiments at a “calibration” field site in Austin, Texas. Numerous conventional in situ and laboratory measurements were performed to characterize the soil at the field site. The “small-scale” nature of the tests involved using a 381?mm (15?in.) diameter, 3.7?m (12?ft) long drilled shaft. Experimental results from this field study provided an opportunity to compare laboratory and field measurements of the G?log?γ and G/Gmax?log?γ curves. This comparison was used to investigate the accuracy of common procedures relating field and laboratory modulus reduction curves. Nonlinear modulus measurements were performed at depths of 1.8?to?2.1?m (6?to?7?ft) in a silt (ML). The field G/Gmax?log?γ curve for this soil at low confining pressures are in general agreement with the laboratory curve from an intact specimen as well as empirical curves. 相似文献
77.
Clayton J. Clark II Michael D. Annable P. S. C. Rao 《Canadian Metallurgical Quarterly》2000,126(11):1033-1038
Remediation of source zones at sites contaminated with dense non-aqueous-phase liquids using aggressive in situ flushing technologies, such as the addition of chemical additives known as cosolvents, have been implemented and successfully demonstrated in recent field tests. However, treatment of the waste fluids generated from such cleanup technologies has not received much attention. The purpose of this laboratory research was to evaluate the feasibility of using sonication as a method for treating waste fluids produced during in situ alcohol flushing at a site contaminated with a dense non-aqueous-phase liquid. Experimental results showed that sonochemical destruction of perchloroethylene (PCE) followed pseudo first-order kinetics and that increasing ethanol cosolvent percentages in the aqueous effluent resulted in decreasing degradation rates of PCE in solution. The energy efficiency (G = degradation∕energy input) of the sonication treatment also decreased as the ethanol volume fraction increased. Overall, sonication was seen to degrade PCE in aqueous solutions, becoming less effective as the cosolvent fraction increased. 相似文献
78.
J. Enrique Juli Yang Liu Sidharth Paranjape Mamoru Ishii 《Nuclear Engineering and Design》2008,238(1):156-169
Traditionally, the flow regimes in two-phase flow are considered in a global sense. However, a local flow regime is required to understand and model the interfacial structures present in the flow. In this work, a new approach has been used to identify both global and local flow regimes in a two-phase upward flow in a 50.8 mm internal diameter pipe under adiabatic conditions. In the present method, the bubble chord length distributions, which are measured simultaneously with three double-sensor conductivity probes, have been used to feed a self-organized neural network. The global flow regime identification results show a reasonable agreement with the visual observation for all the flow conditions. Nonetheless, only the local flow regimes measured at the center of the pipe agree with the global ones. The local flow regime combinations found are analyzed using the flow map information, cross-correlations between the probe signals, and previous correlations. In this way, it is possible to identify eight different global flow regime configurations. 相似文献
79.
The response of a wide range of metals under the action of an applied stress and in environments spanning an entire range of aggressiveness, from the very inert to aggressive has been the subject of several investigations. Most of these studies have focused on mechanisms governing fatigue crack propagation and little attention has been paid to the effect of environment on fatigue crack initiation. A comprehensive understanding of the influence of aqueous environments has been hampered by the complexity of the problem, the difficulties in understanding the various micromechanisms governing crack initiation and crack propagation and by an absence of a truly interdisciplinary attack of the problem. In this paper, several of the fatigue crack initiation models are presented and the micromechanisms governing fatigue crack initiation are examined. The various processes that control the phenomenon of cracking including aqueous environment enhanced fatigue crack growth are also highlighted in this review. 相似文献
80.