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71.
A successive approximation linear quadratic regulator (SALQR)method is applied to solve estuarine management problems to determine the optimal amount of freshwater inflows into baysand estuaries to maximize fishery harvests. Fishery harvests areexpressed in regression equations as functions of freshwaterinflows. The optimization problem is posed as a discrete-timeoptimal control problem in which salinity represents the statevariable and freshwater inflow represents the control variable. A two-dimensional hydrodynamic-salinity transport model, HYD-SAL,is used as the transition to simulate the flow circulation andtemporal and spatial salinity pattern in an estuary system. Thebound constraints for the control and state variables areincorporated into the objective function using a penalty functionmethod to convert the problem into an unconstrained formulation. The SALQR method is applied to the Lavaca-Tres Palacios Estuaryin Texas and the results are compared with those of usingregression equations as the transition equations. 相似文献
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EC Van Os JA McKinney BJ Zins DC Mays ZH Schriver WJ Sandborn JJ Lipsky 《Canadian Metallurgical Quarterly》1996,679(1-2):147-154
We investigated whether linear whole-body acceleration along the interaural y-axis influenced the concurrent perception of visual motion direction as has been shown for angular accelerations. A sled running on air bearings along a 7.5-m track was used to accelerate 18 subjects at two different linear accelerations. These young, healthy volunteers, aged 25.50 +/- 7.38 years, used a joystick to indicate whether or not they perceived visual motion to the left within a random-dot kinematogram continuously presented on a monitor moving with them. The percentage of coherently leftward moving pixels presented for a 640-ms period during acceleration was adjusted according to a Modified Binary Search (MOBS) procedure. Six conditions were tested, two acceleration levels of 1 and 2 m/s2 to both left and right with, at the higher acceleration, two different times of visual motion presentation. Conditions were sequenced by means of a 6 x 6 Latin square balanced for order and carry over. A MANOVA did not show any statistically significant effects either for the independent variables acceleration, velocity, and direction of motion of the sled or for their interactions. The results obtained are in clear contrast to those obtained under rotatory stimulation. We conclude that the otolithic contribution to vestibular-visual motion processing is negligible. 相似文献
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CL Perry DB Bishop G Taylor DM Murray RW Mays BS Dudovitz M Smyth M Story 《Canadian Metallurgical Quarterly》1998,88(4):603-609
OBJECTIVES: A randomized school based trial sought to increase fruit and vegetable consumption among children using a multicomponent approach. METHODS: The intervention, conducted in 20 elementary schools in St. Paul, targeted a multiethnic group of children who were in the fourth grade in spring 1995 and the fifth grade in fall 1995. The intervention consisted of behavioral curricula in classrooms, parental involvement, school food service changes, and industry support and involvement. Lunchroom observations and 24-hour food recalls measured food consumption. Parent telephone surveys and a health behavior questionnaire measured psychosocial factors. RESULTS: The intervention increased lunchtime fruit consumption and combined fruit and vegetable consumption, lunchtime vegetable consumption among girls, and daily fruit consumption as well as the proportion of total daily calories attributable to fruits and vegetables. CONCLUSIONS: Multicomponent school-based programs can increase fruit and vegetable consumption among children. Greater involvement of parents and more attention to increasing vegetable consumption, especially among boys, remain challenges in future intervention research. 相似文献
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LH Sigal JM Zahradnik P Lavin SJ Patella G Bryant R Haselby E Hilton M Kunkel D Adler-Klein T Doherty J Evans PJ Molloy AL Seidner JR Sabetta HJ Simon MS Klempner J Mays D Marks SE Malawista 《Canadian Metallurgical Quarterly》1998,339(4):216-222
The purpose of this study was to determine whether infrared tympanic membrane thermometry can replace mercury-in-glass temperatures as an assessment tool for detecting fevers earlier and more reliably in a pediatric oncology outpatient setting. A total of 313 patient visits had infrared tympanic temperatures (obtained by using the LighTouch LTX Pedi-Q thermometer (Exergen; Watertown, MA) and axillary temperatures taken simultaneously (obtained by using mercury-in-glass thermometers). Those patients with a normal axillary temperature and an elevated tympanic measurement of 38 degrees C or higher had a follow-up axillary temperature conducted that evening to determine whether an elevated tympanic temperature predicted on coming fever or infection. The mean tympanic temperature was 37.5 degrees C and the mean axillary temperature was 36.8 degrees C, a difference of 0.7 degree C (P = .0001). Sixty-two (20%) patients had discrepant temperatures with a febrile tympanic and normal axillary measurement. Three (5%) of these patients were febrile at their follow-up axillary reading. Tympanic thermometry resulted in a significantly higher temperature reading than the axillary method. Elevated tympanic temperatures were not predictive of oncoming fever or infection. Fevers were not missed when using the tympanic method. To prevent unnecessary medical intervention, it is recommended that mercury-in-glass thermometers verify elevated tympanic temperatures. 相似文献
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Smalley Committee R. W. Bates R. W. Bartlett Biffle Owen R. T. Doughtie Jr. O. E. Wilkens T. L. Rettger T. C. Law P. D. Cretien R. W. Bates G. Conner Henry W. T. Coleman E. R. Hahn R. A. Decker F. R. Earle J. R. Mays A. S. Richardson S. J. Rini J. P. Hewlett B. A. Schroeder C. P. Long W. D. Pohle Dan L. Henry N. W. Ziels B. N. Rockwood K. H. Fink C. P. Long 《Journal of the American Oil Chemists' Society》1954,31(8):345-347
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