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361.
Ilkka V. Kojo Ari Jokilaakso Pekka Hanniala 《JOM Journal of the Minerals, Metals and Materials Society》2000,52(2):57-61
1999 marked the 50th anniversary of the Outokumpu flash-smelting process. Originating during the post-World War II energy
crisis, flash smelting is a high-intensity process developed to attain ever-increasing throughputs and intensities. Many innovations
and continuous development ensued during the next 50 years before today’s state-of-the-art copper-making process chain and
environmental benchmarking technology (e.g., Outokumpu flash smelting, Kennecott-Outokumpu flash converting, and flash technology)
became possible. This article reviews how Outokumpu flash furnace design, especially cooling for higher heat loads, has improved
over the years.
For more information, contact I.V. Kojo, Outokumpu Engineering Contractors Oy, P.O. Box 862, FIN-02201 Espoo, Finland; telephone
358-9-4211; fax 358-9-421 3973; e-mail ilkka.kojo@outokumpu.com. 相似文献
362.
We present results on existence of continuous selections of trajectories of hybrid systems evolving according to Lipschitz nonlinear inclusions. First, we utilize the Skorohod metric to define both a family of pseudo-metrics and a metric on the set of trajectories accepted by the hybrid automaton. We show that under a non-Zeno condition the latter metric is complete. Second, the existence of continuous selections with respect to the family of pseudo-metrics is proved under a relatively mild assumption of transversality. 相似文献
363.
364.
A case study of an acute tuberculous bronchiolitis (a rarely encountered form of generalized miliary tuberculosis), whose aggravated progressing resulted in fatal outcome 2 months after the onset of the initial disease signs, is described. The prevalence of non-specific infectious-and-allergic manifestations is a clinical-and-morphological peculiarity within the case study, which confirms a diversity of morphological changes occurring in the organism in tuberculosis infection. The etiological- and pathogenetic specific features of acute tuberculous bronchiolitis in children and in adults are under discussion; in particular, a possible role of a preceding viral infection is evaluated. It is one of the cases of hematogenic generalization in primary tuberculosis of adults, observed by the authors, when an involvement of the pulmonary and parenchymatous organs as well as of arachnoids and substances of the cerebrum was registered. The presence of generalized vasculitis with fibrinoid swelling and with necrosis of collagenous fibers of medium (and with the development of pan-vasculitis in the discussed case) is typical of all such observations. 相似文献
365.
Shapiro Ari D.; Slater Peter J. B.; Janik Vincent M. 《Canadian Metallurgical Quarterly》2004,118(4):447
Call usage learning can be demonstrated on 4 different levels: signaling on command, signaling and refraining from signaling on command, responding to a trained stimulus with a signal from a specific signal class, and responding to the playback of any untrained stimulus with one from the same signal class. Two young gray seals (Halichoerus grypus) were trained successfully to demonstrate the first 2 levels. They also learned to respond to 9 moan stimuli and 9 growl stimuli with vocalizations of the same class (Level 3). However, novel moan and growl stimuli tended to elicit growls. This casts doubt on the possibility that gray seals can reach the 4th level, but it demonstrates that they are capable of the first 3 levels of usage learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
366.
This paper reports novel microcantilever metrology tools to investigate free microjets emanating from a micromachined nozzle of diameter 10 μm. Microcantilevers with an integrated resistive heater-thermometer were used to study microjet cooling and phase change characteristics. While the microcantilever heater was aligned to and impinged upon by hydrocarbon microjets, the heater temperature was modulated by a constant voltage source. Successive heating and cooling cycles captured the microjet phase change hysteresis properties. When the microcantilever heater temperature was controlled, it was possible to construct a full boiling curve. Measurements were made on microjets of butane, hexane, and octane. The convective heat fluxes accompanied by microjet impingement boiling were 2.9–7.6 kW/cm2 for heater temperatures of 25–350 °C. Overall, the techniques reported herein show promise for characterizing microscale jet flows. 相似文献
367.
Olav Tirkkonen Sassan Iraji Ari Hottinen 《International Journal of Wireless Information Networks》2006,13(4):341-355
We consider the problem of designing high rate space–time block codes in multipath fading channels. For this, both minimizing the effect of the self-interference induced by the code itself, and mitigating the inter-symbol-interference induced by the channel have to be addressed. We translate the problem into an equivalent problem of designing a constrained code in a single-path channel with more antennas, and argue that design criteria derived in single-path apply when optimizing this constrained code. Here we concentrate on an analytic measure pertinent to mutual information maximization and BER-performance optimization. The design program is successfully applied to rate one linear space–time transmissions from four transmit antennas. A family of discrete permutations of the transmitted sequences are considered. Performance is optimized within this family, and the results are seen to effect directly both mutual information and error performance. 相似文献
368.
Tapio Sutela Martti Rask Teppo Vehanen Ari Westermark 《Lakes & Reservoirs: Research and Management》2008,13(3):215-220
Parallel sampling of fish, using electrofishing and NORDIC multimesh gillnets, was performed in the littoral areas of eight boreal lakes. Some fish species were caught only by electrofishing (e.g. bullhead, Cottus gobio (L.); burbot, Lota lota (L.)), while some were caught only with gillnets (e.g. pikeperch, Stizostedion lucioperca (L.); smelt, Osmerus eperlanus (L.)). The fish species that were caught with both methods (e.g. perch, Perca fluviatilis (L.) exhibited gear-specific length distributions. A combination of NORDIC gillnetting (passive gear) and electrofishing (active gear) is suggested to reasonably well cover the entire species composition in the littoral zones (≈ 0–3 m depth) of boreal lakes. This gear combination is recommended for evaluating the ecological status of lakes within the European Water Framework Directive. 相似文献
369.
Brea V.M. Vilarino D.L. Paasio A. Cabello D. 《IEEE transactions on circuits and systems. I, Regular papers》2004,51(5):997-1013
This paper introduces the processing core of a full-custom mixed-signal CMOS chip intended for an active-contour-based technique, the so-called pixel-level snakes (PLS). Among the different parameters to optimize on the top-down design flow our methodology is focused on area. This approach results in a single-instruction-multiple-data chip implemented by a discrete-time cellular neural network with a correspondence between pixel and processing element. This is the first prototype for PLS; an integrated circuit with a 9/spl times/9 resolution manufactured in a 0.25 -/spl mu/m CMOS STMicroelectronics technology process. Awaiting for experimental results, HSPICE simulations prove the validity of the approach introduced here. 相似文献
370.
Stark S Julkunen-Tiitto R Holappa E Mikkola K Nikula A 《Journal of chemical ecology》2008,34(11):1382-1391
We investigated latitudinal and regional variations in the composition and concentrations of foliar flavonoids and condensed
tannins in wild populations of white birch (Betula pubescens EHRH) in a large climatic transect in Finland. Concentrations of quercetin derivatives were correlated positively with latitude.
By contrast, the concentrations of apigenin and naringenin derivatives were correlated negatively with latitude. These compound-specific
latitudinal gradients compensated each other, resulting in no changes in the concentration of total flavonoids. Our results
thus demonstrate a qualitative, but not quantitative, latitude-associated gradient in the foliar flavonoids in white birch.
Due to higher antioxidant capacity of the quercetin derivatives in relation to other flavonoids, the qualitative change can
reflect higher adaptation to light in the north than south. An investigation on a regional scale in the northern boreal zone
showed that the temperature sum was correlated positively and soil P concentration was correlated negatively with the concentrations
of foliar flavonoid, while the concentration of condensed tannins was correlated with slope. The variation in concentrations
of flavonoids at large-scale geographical patterns is in line with the conjecture that foliar flavonoids are synthesized for
protection against photooxidative stress. 相似文献