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91.
D.J. Pedregal R. Rivas V. Feliu L. Sánchez A. Linares 《Environmental Modelling & Software》2009,24(4):502-509
This paper addresses the problem of modelling and forecasting river flows and levels based on flood routing type models. Though this is generally considered as a non-linear problem, very often it is treated by linear models. A forecasting system is built for the level and flow measurements registered in the Ebro River at the station of Zaragoza (Spain), with the main purpose of preventing floods in an early stage of development. The model takes advantage of the wealth of data available at the Ebro Hydrographical Confederation and is non-linear in essence. The system is obtained by application of system identification tools, starting from a linear specification and relating the parameters of the model estimated to some transformation of the input in the system. Such transformation requires the application of a Kalman Filter in a particular set up and the full estimation algorithm involves an iterative procedure. The model is fully developed on a data set and is thoroughly validated on a different span of data. 相似文献
92.
J García Marco A Miguel Sosa J García Conde A Miguel García C Arbona V Escrig I Benet I Navarro A Ruiz F Carbonell 《Canadian Metallurgical Quarterly》1994,39(4):241-244
PURPOSE: To assess the "in vivo" effect of 13-cis-retinoic acid and low dose Ara-C in MDS as well as to establish "in vitro" advantage of retinoid dose-related growth pattern on bone marrow cultures as defined by culture timing and CFU-GM proliferative response. PATIENTS AND METHODS: We evaluated 28 patients diagnosed of MDS according to FAB classification, of whom 4 cases had RA, 8 cases SRA, 14 cases RAEB and 2 cases RAEB-T. Patients who had RA and SRA were treated with oral 13-cis-retinoic acid at doses of 20-40 mg daily for 4 months and those cases with RAEB and RAEB-T had subcutaneous Ara-C at doses of 3 mg/m2 twice a day for 21 days. The "in vivo" and "in vitro" effect of retinoic acid on the haemopoietic differentiation was evaluated by the growth CFU-GM in semisolid cell culture methods. RESULTS: Increasing in vitro concentrations of 13-cis retinoic acid did not enhance the growth of myelodysplastic progenitors. Nevertheless, our study did not find any beneficial therapeutic effect of retinoic compounds in MDS patients. In this study, low-dose Ara-C (3 mg/m2) showed similar effects when compared with higher doses reported by others. Furthermore, in terms of CFU-GM proliferation the concentration of colonies before and after treatment were fairly similar in all but two patients. CONCLUSIONS: The results drawn from our study demonstrated that there is no beneficial advantage of 13-cis-retinoic acid as a differentiation inducing agent on myelodysplastic patients. In contrast, lower doses of Ara-C showed similar effects on haemopoiesis of MDS patients than standard doses of 10-20 mg/m2 but with less side effects. 相似文献
93.
Summary The thermal stabilities of poly(-methylhydrogenitaconate-co-2-methyl-2-oxazoline) and poly(-methylhydrogenitaconate-co-2-ethyl-2-oxazoline) obtained by spontaneous copolymerization have been studied by programmed thermogravimetric analysis over the temperature range from 293 K to 773 K under a flow of nitrogen. Most of the copolymers do not show weight loss until 473 K and they degrade in one step. The kinetic parameters Ea, n and A were obtained following one method of thermogravimetric analysis. The reaction order for all copolymers was 1.0. The poly(-methylhydrogenitaconate-co-2-methyl-2-oxazoline)s were the most thermostable copolymers. 相似文献
94.
The synthesis of a water-insoluble metal ion complexing resin was carried out by radical polymerization of 2,2-bis(acrylamido) acetic acid. The resin was characterized by elemental analyses, FTIR spectroscopy, and thermal analyses. The ability to bind copper(II), iron(II), iron(III), and uranium(VI) as well as the elution of the metal ions from the loaded resins were studied. For uranyl ions, pH 5 was the optimum sorption pH value. Sorption selectivity from the binary mixture Cu(II) + U(VI) was studied at pH 2. The thermal stability is increased by adsorption of UO. According to these results a coordination mechanism is suggested for sorption of copper and uranium. © 1995 John Wiley & Sons, Inc. 相似文献
95.
Summary The solution behaviour of the polycarboxylic acid derived from scleroglucan (sclerox) has been investigated as a function of NaOH concentration and temperature by means of polarimetry and viscosimetry techniques. In comparison to the native polymer, sclerox is less sensitive to degradation at high NaOH concentration (up to NaOH equal to 0.4 M) and thermally more stable. The viscosity data show a normal polyelectrolyte effect and the polymer chains seem to be not stiff. We conclude that at high pH sclerox chains are in a flexible, probably single stranded conformation. 相似文献
96.
Comfort of personal protective equipment 总被引:1,自引:0,他引:1
The degree of comfort of personal protective equipment (PPE) was investigated in an automobile encapsulating plant. Up to 96.2% of employees used one or a combination of PPE. Only 8% of the workers felt their respirators were comfortable, 30% tolerated their respirators, and 62% rated them as uncomfortable. The percentage of employees who rated their PPE (other than a respirator) as comfortable ranged from 32 to 52%. For comfort factor, coveralls/aprons rated 52%, safety glasses 51%, rubber gloves 42%, and hearing protectors 36%. PPE was tolerable (just acceptable) for about 30% of the employees. To increase the effectiveness and safety of PPE, the human-factor aspects of PPE design should be emphasized more and quality improvement should cover the wearability of PPE. 相似文献
97.
Fouto Ana R. Nunes Rita G. Pinto Joana Alves Luísa Calado Sofia Gonçalves Carina Rebolo Margarida Viana-Baptista Miguel Vilela Pedro Figueiredo Patrícia 《Magma (New York, N.Y.)》2022,35(5):779-790
Magnetic Resonance Materials in Physics, Biology and Medicine - Histogram-based metrics extracted from diffusion-tensor imaging (DTI) have been suggested as potential biomarkers for cerebral small... 相似文献
98.
Ortega-Cabezas Pedro Miguel Colmenar-Santos Antonio Borge-Diez David Blanes-Peiró Jorge Juan Higuera-Pérez Jorge Alcaide Eric 《Software Quality Journal》2022,30(3):687-728
Software Quality Journal - The number of electronic control units (ECU) installed in vehicles is increasingly high. Manufacturers must improve the software quality and reduce cost by proposing... 相似文献
99.
100.
We investigate the dynamics of granular flows under the action of a centrifugal acceleration field. The granular flows consist of a monodisperse set of glass beads flowing down an inclined plane. The experiments are performed at variable slope angles \(\zeta \) and equivalent centrifugal accelerations \(a_\text {cf}\equiv Ng\). We study the effect of this parameters on the superficial flow velocity u and flow height h. Two trends are observed, by increasing \(\zeta \) and \(a_\text {cf}\), u increases proportionally, and h decreases asymptotically until a constant height. This relation is analysed in terms of the system potential and kinetic energy, leading to the estimation of equivalent impact forces one order of magnitude larger than those observed in small scale 1g laboratory experiments, with the possibility to reach higher forces by increasing N. Finally, considering the trend of u and h, our results suggest a scaling principle of inertial velocity proportional to \(\sqrt{N}\). 相似文献