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81.
82.
Forty-seven patients with cancer of the lower half of the oral cavity underwent primary restoration of mandibular continuity with a threaded wire after "en bloc" resection. The overall 3 years tolerance rate of the wire calculated according to the actuarial method is 0.29. Preoperative radiotherapy and inclusion of the wire into silastic reduced tolerance of the prosthesis. The occurrence of an oral fistula required removal of the wire.  相似文献   
83.
The feasibility of anaerobic ammonium oxidation (anammox) process to treat wastewaters containing antibiotics and heavy metals (such as the liquid fraction of the anaerobically digested swine manure) was studied in this work. The specific anammox activity (SAA) was evaluated by means of manometric batch tests. The effects of oxytetracycline, sulfathiazole, copper and zinc were studied. The experimental data of the short-term assays were fitted with an inhibition model to identify the half maximal inhibitory concentration (IC(50)). After 24 h exposures, IC(50)-values equal to 1.9, 3.9, 650 and 1,100 mg L(-1) were identified for copper, zinc, sulfathiazole and tetracycline respectively. The effect of prolonged exposure (14 days) to oxytetracycline and sulfathiazole was studied by means of repeated batch-assays. Anabolism and catabolism reactions were active during the inhibition tests indicating that anammox bacteria could grow even in the extreme conditions tested. Considering the average concentrations expected in swine wastewaters, the inhibitors studied do not seem to represent a problem for the application of the anammox process. However, in order to verify the effect of these compounds on the growth of anammox bacteria, continuous culture experiments could be conducted.  相似文献   
84.
Due to changes in the Dutch flood management paradigm, governance practices have been shifting from technocratic and state-oriented towards more collaborative governance approaches in which many governmental actors, together with private and societal actors, search out integral solutions. This shift has had an impact on how water management is legitimized. This paper evaluates two water governance processes that reflect the new management paradigm in different ways, and analyzes how these changing paradigms influence the democratic legitimacy of water governance. It is concluded that the extent to which the new paradigm is implemented influences the way in which democratic legitimacy is organized. It is also shown that new forms of democratic legitimacy do not replace existing ones but rather contribute to hybrid and contextualized forms of legitimacy.  相似文献   
85.
This work aims to model the optimal control of dike heights. The control problem leads to so-called Hamilton-Jacobi-Bellman (HJB) variational inequalities, where the dike-increase and reinforcement times act as input quantities to the control problem. The HJB equations are solved numerically with an Essentially Non-Oscillatory (ENO) method. The ENO methodology is originally intended for hyperbolic conservation laws and is extended to deal with diffusion-type problems in this work. The method is applied to the dike optimisation of an island, for both deterministic and stochastic models for the economic growth.  相似文献   
86.
A behavioural pseudometric is often defined as the least fixed point of a monotone function F on a complete lattice of 1-bounded pseudometrics. According to Tarski?s fixed point theorem, this least fixed point can be obtained by (possibly transfinite) iteration of F, starting from the least element ⊥ of the lattice. The smallest ordinal α such that Fα()=Fα+1() is known as the closure ordinal of F. We prove that if F is also continuous with respect to the sup-norm, then its closure ordinal is ω. We also show that our result gives rise to simpler and modular proofs that the closure ordinal is ω.  相似文献   
87.
88.
This paper proposes a novel method for preference relaxation in online product search, which enables consumers to make quality choices without suffering from the commonly experienced information overload. In online shopping scenarios that involve multi-attribute choice tasks, it can be difficult for consumers to process the vast amounts of information available and to make satisfactory buying decisions. In such situations consumers are likely to eliminate potentially good choices early on, using hard-constraint filtering tools. Our approach uses edge sets to identify the alternatives on the soft boundary and the principle of alternative domination to suppress the alternatives on this boundary that are irrelevant. We demonstrate how our approach outperforms existing methods for product search in a set of simulations using two sets of 2650 car advertisements and 1813 digital cameras gathered from a popular online store.  相似文献   
89.
In this paper we present a machine learning framework to analyze moving object trajectories from maritime vessels. Within this framework we perform the tasks of clustering, classification and outlier detection with vessel trajectory data. First, we apply a piecewise linear segmentation method to the trajectories to compress them. We adapt an existing technique to better retain stop and move information and show the better performance of our method with experimental results. Second, we use a similarity based approach to perform the clustering, classification and outlier detection tasks using kernel methods. We present experiments that investigate different alignment kernels and the effect of piecewise linear segmentation in the three different tasks. The experimental results show that compression does not negatively impact task performance and greatly reduces computation time for the alignment kernels. Finally, the alignment kernels allow for easy integration of geographical domain knowledge. In experiments we show that this added domain knowledge enhances performance in the clustering and classification tasks.  相似文献   
90.
The threshold gradient for perception of a linear change in luminance with time has been measured as a function of the stimulus duration. These data are compared with the "De Lange" curves representing the flicker sensitivity measured with intermittent presentation of the stimulus as a function of the stimulus duration. For this purpose it is necessary to take into account the fact that a linear luminance gradient, being a relatively low-frequency signal, is affected less by the low-pass filter supposedly situated in the visual system than by a sinusoidal signal (flicker) of the same duration.  相似文献   
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