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51.
In areas where tap water has a high salt content, wastewater is not appropriate for reuse in agriculture, particularly for sensitive crops. One alternative is reduction, via desalination, of the brackish character to the secondary effluent. A filtration stage is also required before desalination. On the other hand, used reverse osmosis membranes can be recycled and used as filters in the advanced treatment stage in order to reduce suspended matter contained in the secondary effluent—one advantage being the environmental recovery of solid waste. Used membranes can be treated with strong chemical oxidants to peel off the active separation layer in order to transform them into microfiltration or ultrafiltration elements. Preliminary tests have been carried out with 8″ elements, aimed at comparing membrane performance before and after the peeling process. An index denoted as peeling effectiveness (high flux, high salt passage) is used for comparison. It was soon observed that potassium permanganate was more effective than others, together with sodium hydroxide. Doses around 1000 mg/L KMnO4 provided the best results. It was also concluded that membrane cleaning, done with sodium bisulphite prior to peeling, was better when recirculating the cleaning solution around the membrane rather than soaking it. Next steps in the research will test the actual filtration capability of the peeled membranes in actual wastewater.  相似文献   
52.
Functions that optimize Laplacian‐based energies have become popular in geometry processing, e.g. for shape deformation, smoothing, multiscale kernel construction and interpolation. Minimizers of Dirichlet energies, or solutions of Laplace equations, are harmonic functions that enjoy the maximum principle, ensuring no spurious local extrema in the interior of the solved domain occur. However, these functions are only C0 at the constrained points, which often causes smoothness problems. For this reason, many applications optimize higher‐order Laplacian energies such as biharmonic or triharmonic. Their minimizers exhibit increasing orders of continuity but lose the maximum principle and show oscillations. In this work, we identify characteristic artifacts caused by spurious local extrema, and provide a framework for minimizing quadratic energies on manifolds while constraining the solution to obey the maximum principle in the solved region. Our framework allows the user to specify locations and values of desired local maxima and minima, while preventing any other local extrema. We demonstrate our method on the smoothness energies corresponding to popular polyharmonic functions and show its usefulness for fast handle‐based shape deformation, controllable color diffusion, and topologically‐constrained data smoothing.  相似文献   
53.
The present study examined the impact of a judicial warning, witness age, and the method of testimony presentation on mock jurors' perceptions of credibility of witnesses and accused, and on guilty verdicts. The participants were 435 undergraduate university students who listened to an audio-taped summary of a theft trial followed by abbreviated instructions to the jury. Witness age was 7, 10, or 23, the jury warning was either present or absent when witnesses were children, and the testimony by the prosecution eyewitness and accused were either presented or summarized. For the taped testimony conditions, the mock witnesses and the accused read a fact pattern describing the events in the case and were audiotaped as they answered a series of questions, which constituted direct and cross-examination. The testimony of the 7-year-old child, compared to the 10-year-old, was associated with lower cognitive competence and higher suggestibility, but also with higher accuracy of recall (lower mistaken recollection) and lower credibility of accused. The pattern of results for appraisal of the older child was more similar to that of an adult witness. The young adult was judged to be less trustworthy than children of either age. While the presence of a warning had no impact on guilty verdicts when a 7-year-old was a witness, there were fewer guilty verdicts when a witness was 10 years old. Participants also made fewer guilty verdicts when a young adult's testimony, compared to conditions involving child witnesses, was presented, but not when it was summarized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
A modified microwave-assisted polyol method was applied to prepare nanoparticulate ceramic powders of different oxides, i.e. Gd2O3, AlO(OH) (boehmite) and TiO2. Due to the good dielectric properties of the utilised solvents, such as ethylene glycol, diethylene glycol and 1,4 butanediol, a significant decrease in reaction time was achieved under microwave heating. In the case of AlO(OH) and Gd2O3, <5 nm primary particle size were obtained. Boehmite was found to be intercalated with the solvent. The general applicability of the process is shown and the advantages in terms of properties and processibility are described. The powders thus prepared were investigated using X-ray diffractometry, electron microscopy and physisorption.  相似文献   
55.
In computer and electronic manufacturing, it is very important to be able to automatically check whether the surface mounted devices (SMD) are correctly placed on the printed circuit boards. The inspection of these boards has to be done on a shop floor, where statistical characteristics of the noise vary so much that, in essence, we only have interval estimates for this noise.We show that under this interval uncertainty, the optimal image processing technique consists of using Haar wavelets. Wavelets indeed lead to much better results than previously used Fourier transform techniques.On a more fundamental level, our result is a step towards solving an important problem related to wavelets: that wavelet transforms often empirically work much better than other methods, but there are very few theoretical explanations of this efficiency. Our results shows that, probably, such a theoretical explanation can be obtained if we take interval uncertainty into consideration.  相似文献   
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The problem of defuzzification is examined in this paper from a broader perspective as a special way of dealing with the general problem of retranslation. The paper includes an overview of different formulations of the problem of defuzzification, as well as an overview of methods that have been suggested in the literature for dealing with the problem. Our own approach to defuzzification, which is described in the paper in more details, is based on relevant measures of uncertainty-based information. This paper is a companion to our recent paper that addresses the general problem of retranslation in computing with perceptions (Martin and Klir 2006).  相似文献   
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The prevalence of metabolic disorders, such as type 2 diabetes (T2D), obesity, and non-alcoholic fatty liver disease (NAFLD), which are common risk factors for cardiovascular disease (CVD), has dramatically increased worldwide over the last decades. Although dietary habit is the main etiologic factor, there is an imperfect correlation between dietary habits and the development of metabolic disease. Recently, research has focused on the role of the microbiome in the development of these disorders. Indeed, gut microbiota is implicated in many metabolic functions and an altered gut microbiota is reported in metabolic disorders. Here we provide evidence linking gut microbiota and metabolic diseases, focusing on the pathogenetic mechanisms underlying this association.  相似文献   
60.

Groundwater is a primary source of drinking water in the Mediterranean, however, climate variability in conjunction with mismanagement renders it vulnerable to depletion. Spatiotemporal studies of groundwater recharge are the basis to develop strategies against this phenomenon. In this study, groundwater recharge was spatiotemporally quantified using the Soil and Water Assessment Tool (SWAT) in one coastal and one inland hydrological basin in Greece. A double calibration/validation (CV) procedure using streamflow data and MODIS ET was conducted for the inland basin of Mouriki, whereas only ET values were used in the coastal basin of Anthemountas. Calibration and simulation recharge were accurate in both sites according to statistical indicators and previous studies. In Mouriki basin, mean recharge and runoff were estimated as 16% and 9%, respectively. In Anthemountas basin recharge to the shallow aquifer and surface runoff were estimated as 12% and 16%, respectively. According to the predicted RCP 4.5 and 8.5 scenarios, significant variations in groundwater recharge are predicted in the coastal zone for the period 2020–2040 with average annual recharges decreasing by 30% (RCP 4.5) and 25% (RCP 8.5). Variations in groundwater recharge in the inland catchment of Mouriki were insignificant for the simulated period. Anthemountas basin was characterized by higher runoff rates. Groundwater management in coastal aquifers should include detailed monitoring of hydrological parameters, reinforced groundwater recharge during winter and reduced groundwater abstraction during summer depending on the spatiotemporal distribution of groundwater recharge.

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