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91.
A mathematical model able to predict solid and drying gas temperature and moisture content axial profiles along a direct contact rotary dryer was developed. The study was focused on the drying kinetics based on phenomenological models. Two different drying mechanisms in the decreasing drying rate period were tested: proponional to the unbound moisture content and moisture diffusion inside the particle. Experimental data collected in a pilot-scale direct contact rotary dryer was used to validate the model. Soya and fish meals were used as drying material. 相似文献
92.
We examined situational antecedents of dieting relapse crises and dieters' attempts to cope with temptations to overeat. We analyzed postreatment interviews with 57 obese Ss with Type II diabetes, comparing situations in which Ss lapsed with those in which they overcame temptation to overeat. Cluster analysis yielded 3 categories of relapse crises: mealtime, low-arousal, and emotional upset situations. The cluster differed in outcome: Upset situations almost always resulted in overeating; situational factors, especially food-related cues, increased relapse risk; but performance of coping was the strongest correlate of outcome. Cognitive and behavioral coping responses were each equally associated with positive outcomes. When Ss reported combining both types of coping, they were less likely to report overeating. The dynamics of relapse crises among dieters resemble those that govern relapse crises in addictive behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
T. Perez M. Radziunas H.-J. Wunsche C.R. Mirasso F. Henneberger 《Photonics Technology Letters, IEEE》2006,18(20):2135-2137
We present numerical simulations describing the dynamics of two multisection semiconductor lasers emitting in a chaotic regime coupled in a master-slave configuration. By changing the current of the passive section of the master laser, we observe a change in the maximum correlation between the outputs of the two systems. These devices are promising candidates for on-off phase-shift keying encryption. 相似文献
94.
Precise timing and asynchronous I/O are appealing features for many applications. Unix kernels provide such features on a per‐process basis, using signals to communicate asynchronous events to applications. Per‐process signals and timers are grossly inadequate for complex multithreaded applications that require per‐thread signals and timers that operate at finer granularity. To respond to this need, we present a scheme that integrates asynchronous (Unix) signals with user‐level threads, using the ARIADNE system as a platform. This is done with a view towards support for portable, multithreaded, and multiprotocol distributed applications, namely the CLAM (connectionless, lightweight, and multiway) communications library. In the same context, we propose the use of continuations as an efficient mechanism for reducing thread context‐switching and busy‐wait overheads in multithreaded protocols. Our proposal for integrating timers and signal‐handling mechanisms not only solves problems related to race conditions, but also offers an efficient and flexible interface for timing and signalling threads. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
95.
This paper analyses the technical efficiency in the hydroelectric generating plants of a main Portuguese electricity enterprise EDP (Electricity of Portugal) between 1994 and 2004, investigating the role played by increase in competition and regulation. A random cost frontier method is adopted. A translog frontier model is used and the maximum likelihood estimation technique is employed to estimate the empirical model. We estimate the efficiency scores and decompose the exogenous variables into homogeneous and heterogeneous. It is concluded that production and capacity are heterogeneous, signifying that the hydroelectric generating plants are very distinct and therefore any energy policy should take into account this heterogeneity. It is also concluded that competition, rather than regulation, plays the key role in increasing hydroelectric plant efficiency. 相似文献
96.
Relaxed stability and performance conditions for Takagi-Sugeno fuzzy systems with knowledge on membership function overlap. 总被引:1,自引:0,他引:1
Antonio Sala Carlos Ari?o 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(3):727-732
This correspondence presents a relaxation of some earlier linear matrix inequality (LMI) conditions, which allow setting up less conservative stability or performance conditions for Takagi-Sugeno fuzzy models. Unlike the previous literature, this correspondence takes into account the knowledge of the membership functions' shape by considering bounds on them and their cross products (interpreted as an overlap measure), introducing auxiliary LMI variables. Numerical examples illustrate the achieved improvements. 相似文献
97.
98.
99.
Generalizations and unification of the celebrated Paris’ and Wöhler’s laws for fatigue crack propagation are derived by applying the recently developed quantized (or finite) fracture mechanics. In particular, three generalized Paris’, Wöhler’s or unified laws are proposed and compared, demonstrating their applicability for predicting the life time of structures containing from small (the Wöhler’s regime) to large (the Paris’ regime) propagating fatigue cracks. 相似文献
100.
R Zanardi L Franchini M Gasperini E Smeraldi J Perez 《Canadian Metallurgical Quarterly》1997,12(4):195-197
The aim of this open pilot study was to evaluate the efficacy of fluvoxamine in the continuation as well as in the maintenance therapy of delusional depression. Thirty patients with recurrent, unipolar depression (DSM-IV criteria) were selected who had at least one depressive episode during the 18 months preceding the delusional depressive index episode and were treated with fluvoxamine 300 mg/day. Twenty-five of them had a sustained response to this short-term treatment and agreed to enter into the 30-month follow up study. All participants completed the follow up period. No relapse was observed during the 6 months of continuation therapy. During the further 24 months of maintenance therapy, 80% of the patients remained well, whereas 20% (five out of 25) had a single recurrence. Based on these observations, fluvoxamine might be a promising drug for long-term therapy of delusional depression. Further controlled studies are required to confirm this finding. 相似文献