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71.
Testing of the multi-application small light water reactor (MASLWR) passive safety systems 总被引:1,自引:0,他引:1
Jose N. Reyes John Groome Brian G. Woods Eric Young Kent Abel You Yao Yeon Jong Yoo 《Nuclear Engineering and Design》2007,237(18):1999-2005
Experimental thermal hydraulic research has been conducted at Oregon State University for the purpose of assessing the performance of a new reactor design concept, the multi-application small light water reactor (MASLWR). The MASLWR is a pressurized light water reactor design with a net output of 35 MWe that uses natural circulation in both normal and transient operation. Due to its small size, portability and modularity, the MASLWR design is well suited to help fill the potential need for grid appropriate reactor designs for smaller electricity grids as may be found in developing or remote regions. The purpose of the OSU MASLWR test facility is to assess the operation of the MASLWR under normal full operating pressure and full temperature conditions and to assess the passive safety systems under transient conditions. The data generated by the testing program will be used to assess computer code calculations and to provide a better understanding of the thermal-hydraulic phenomena in the design of the MASLWR NSSS. During this testing program, four tests were conducted at the OSU MASLWR test facility. These tests included one design basis accident and one beyond design basis accident. During the performance of these tests, plant operations to include start up, normal operation and shut down evolutions were demonstrated successfully. 相似文献
72.
73.
The development of microstructure and its influence on creep properties have been studied for structures including equiaxed
γ, duplex, and other structures of varying α
2 morphology in two Ti-48Al-2Cr-2Nb alloys. Heat treatments at 1125 °C have been utilized to produce equiaxed γ microstructures in alloys with or without Mo additions. The γ → α transformation produces α
2 plates with several orientation variants within γ grains during subsequent annealing of the equiaxed γ microstructures below the α transus. Formation of this α
2 morphology results from rapid up-quenching (UQ), and this structure persists through annealing, cooling, and creep testing.
Differences in minimum creep rates for several microstructures containing varying amounts of multi- or single variant γ/α
2 grains are shown to be minimal. The presence of Mo has also resulted in improved creep resistance in equiaxed γ and γ+α
2+B2 structures, as compared to similar microstructures in the Ti-48Al-2Cr-2Nb alloy. Deformation during creep at 760 °C at
stresses between 200 and 400 MPa occurs by a combination of twinning and dislocation glide without recrystallization, resulting
in power-law stress exponents in the range of 6 to 9. Only minimal strain path dependence of the minimum creep rate is detected
in a comparison of creep rates in stress jump, stress drop, and single stress tests.
This article is based on a presentation made in the symposium “Fundamentals of Gamma Titanium Aluminides,” presented at the
TMS Annual Meeting, February 10–12, 1997, Orlando, Florida, under the auspices of the ASM/MSD Flow & Fracture and Phase Transformations
Committees. 相似文献
74.
75.
Alexander Gatch Dimitry Gorsky Zy Biesinger Eric Bruestle Kelley Lee Curt Karboski Meredith L. Bartron Tyler Wagner 《Journal of Great Lakes research》2021,47(2):486-493
Restoration of a wild-produced lake trout Salvelinus namaycush population in Lake Ontario has not been successful despite the adult population often meeting or exceeding restoration targets. Lack of high-quality spawning habitat in Lake Ontario is suggested as one impediment to recruitment of wild lake trout, although the quantity and location of spawning habitat is poorly understood. If high-quality spawning habitat is limited in Lake Ontario, lake trout may be using uncommon spawning locations such as rivers. Anecdotal angler accounts point to the Niagara River as a lake trout spawning location. To better understand the potential of the Niagara River as a spawning location, egg and juvenile fish collections were conducted 12–14 river kilometers from the mouth of the Niagara River from 2010 to 2012; and mature female lake trout with surgically implanted acoustic tags were monitored from 2015 to 2019. Genetic analyses confirmed 60% of collected eggs and 93% of collected post-hatch juvenile fish in the Niagara River were lake trout. Tagged female lake trout returned to the Niagara River over consecutive years during the spawning season. The short duration of lake trout presence in the river (mean = 56 days/year) suggests female lake trout use the Niagara River primarily for spawning. Diversity in spawning locations may provide lake trout population’s resilience against environmental variability through a portfolio effect. Improved identification of riverine spawning locations, including their overall contribution to wild recruitment, may be a useful tool for managers to restore a wild-produced population of lake trout in Lake Ontario. 相似文献
76.
Wang Eric Ke Wang Fan Kumari Saru Yeh Jyh-Haw Chen Chien-Ming 《The Journal of supercomputing》2021,77(3):3024-3043
The Journal of Supercomputing - Accidents often occur in the earth—typhoons, floods, earthquakes, traffic accidents and so on. Whether these accidents can be timely and effectively responded... 相似文献
77.
Journal of Mathematical Imaging and Vision - A correction to this paper has been published: https://doi.org/10.1007/s10851-021-01028-0 相似文献
78.
Randy V. Bradley Renée M. E. Pratt Terry Anthony Byrd Christina N. Outlay Donald E. Wynn Jr. 《Information Systems Journal》2012,22(2):97-127
Despite the possible benefits of implementing healthcare information technologies, successful implementation of effective healthcare information technology is constrained by cultural and regulatory concerns and technical obstacles encountered when establishing or upgrading an organisation's enterprise infrastructure. In this paper, we advance Ross' four‐stage model of enterprise architecture maturity as a valuable IT resource for helping healthcare organisations sustain a competitive advantage. We use partial least squares (PLS) structural equation modelling to analyse survey data from 164 US hospitals at different stages of EA maturity. Our results provide evidence that enterprise architecture maturity directly influences the effectiveness of hospitals' IT resources for achieving strategic goals. Further, enterprise architecture maturity indirectly influences the effectiveness of IT resources when IT alignment is incorporated as a mediating variable. We discuss the implications of our findings for research and practice and suggest opportunities for future research. 相似文献
79.
80.
This paper presents a model of labor participation calibrated on a weekly basis; part-time and full-time employments are also
considered. By applying the theory of random utility maximization we model households’ choices. In order to have a good temporal
and spatial coverage the model is calibrated on three datasets, extracted from both national and regional travel surveys.
The results are applied to synthetic households that reproduce the Belgian population. The proposed innovative methodology
simulates synthetic agents by accounting both for households’ and individuals’ characteristics, while not suffering from the
problem of the “zero cell value”. The results indicate that there is major day-to-day variability in working activity participation;
in particular, on Wednesdays and Fridays the number of households working part-time or not working is particularly high. This
is consistent with what was expected by the analysts. Working participation is a fundamental component in activity based models
where work is considered a skeletal activity. The tools developed here can be useful to study how changes in population characteristics
(i.e. increases of flexible working arrangements and of the number of women in the work force) affect activity participation
and travel patterns. 相似文献