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81.
In this paper the flood problem of the river Demer, a river located in Belgium, is discussed. First a simplified model of the Demer basin is derived based on the conceptual reservoir modeling concept. This model was calibrated to simulations results with a more detailed full hydrodynamic model. Afterwards, the focus is shifted to a nonlinear model predictive controller (NMPC) which is based on a new semi-condensed optimization procedure combined with a line search approach. Finally, simulations are performed based on historical data in which the NMPC is compared with the current control strategy used by the local water administration. Uncertainties are added to the rainfall predictions in order to assess the robustness of the NMPC.  相似文献   
82.
Five experiments investigated the role of sublexical units in English single word production L. Ferrand, J. Segui, and G. W. Humphreys (1997) reported a priming effect that was most effective when primes and targets shared the first syllable. Experiments 1A and 1B failed to replicate this effect but Experiment 1B showed that subsyllabic units play a role in speech production. This role was further explored using a picture naming task in Experiment 2. Naming latencies were shortest when the segmental overlap between prime and target (picture name) was largest, regardless of the syllable structure of the target. Experiments 3 and 4 replicated this segmental overlap effect with different sets of words as targets. Experiment 5 showed that the magnitude of the overlap effect increased with longer prime exposure duration. The implications of these results for theories of phonological encoding in speech production are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
The Danish Action Plan against Repetitive Work is presented and discussed as a possible new strategy for regulating repetitive work as well as other complicated working environment problems. The article is based on an empirical evaluation of the Action Plan. The assessment of the Action Plan indicates that a measurable reduction of repetitive work has been achieved, while recognizing that new management strategies focusing on human resource development have also played an important role. These results are used to suggest that—under certain conditions—a combination of state regulation and industrial relation agreements can be used to regulate other working environment problems. © 2001 John Wiley & Sons, Inc.  相似文献   
84.
Epidemiological simulation models to be used primarily to augment the teaching of epidemiology to medical students and other individuals concerned with public health and control of epidemics are presented. Interactive simulations are used to expose students to ``realistic' epidemic situations and permit them to experiment with various control strategies. Criteria by which simulations for such teaching purposes may be evaluated are proposed and operating simulations, MEASLES and INFLU, are described in detail. Information is provided regarding user experience with the above simulations.  相似文献   
85.
This study examined reactions to minority and majority positions that were either stable or reversed through group conversion that transformed opponents (supporters) of the minority (majority) into supporters, (opponents) or through group expansion that brought new supporters (opponents) for the minority (majority) into the group. Minorities who became majorities through group expansion, compared with those who changed through group conversion, perceived their supporters and the overall group as significantly more similar to the self, and had significantly higher expectations for future positive interactions within the group. Perception of similarity with the supporters mediated the effect of the experimental conditions on perception of the overall group-self similarity. Implications of changes through conversion and expansion for the functioning of social groups are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
The determination of water application parameters for creating an optimal soil moisture profile represents a complex nonlinear optimization problem which renders traditional optimization into a cumbersome procedure. For this reason, an alternative methodology is proposed which combines a numerical subsurface flow model and artificial neural networks (ANN) for solving the problem in two, fully separate steps. The first step employs the flow model for calculating a large number of wetting profiles (output), obtained from a systematic variation of both water application and initial soil moisture (input). The resulting matrix of corresponding input/output values is used for training the ANN. The second step, the application of the fully trained ANN, then provides the irrigation parameters which range from a specified initial soil moisture to a desired crop-specific soil moisture profile. In order to avoid substantial disadvantages associated with the common feedforward backpropagation approach, a self-organizing topological feature map is implemented to perform this task. After a comprehensive sensitivity analysis, the new methodology is applied to the outcome of an irrigation experiment. The convincing results recommend the new methodology as a positive contribution towards an improved irrigation efficiency.  相似文献   
87.
In‐situ deformation tests have been performed on a steel displaying the transformation‐induced plasticity (TRIP) effect, while monitoring the phase transformation by means of X‐ray diffraction. A tensile stress is applied to 0.4 mm thick samples of this steel with mass contents of 0.26 % Si, 1.5 % Mn, and 1.8 % Al in a transmission geometry for a synchrotron‐radiation beam of 25 μm · 25 μm. On the diffraction patterns every grain appears as a discrete spot. The austenite {200} reflections are analysed during this investigation. The diffraction patterns are treated like a powder pattern for five different η‐angles, with η representing the angle between the tensile direction and the normal direction of the diffracting {200} planes. The results of the analysis show that η = 0° and η = 90° are the preferential orientations for the transformation to martensite. The Ludwigson and Burger model [9] is used to gain more information about the stress dependence of the deformation induced martensite formation. The microdiffraction patterns also reveal the changes in carbon concentration in austenite at each retained austenite fraction.  相似文献   
88.
89.
Responds to P. T. Costa and R. R. McCrae's reply (see record 1992-25762-001) to the Y. S. Ben-Porath and N. G. Waller article (see record 1992-25755-001) by clarifying the following points: (1) "Normal" personality instruments such as the NEO Personality Inventory should not be used in place of clinical measures, but may serve to provide useful supplemental information; (2) evaluation of the clinical validity of individual test protocols is a vital component of clinical assessment; (3) ordering of scales on a profile implies configural interpretation of test scores, which is common practice in clinical assessment; (4) anxiety, depression, and impulsiveness are viewed by some clinicians as being related to different higher order domains; and (5) clinical correlates thought to be associated with conscientiousness are readily assessable by clinical inventories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
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