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941.
Multimedia Tools and Applications - Image distortion effects, called noise, may occur due to various reasons such as image acquisition, transfer, and duplication. Image denoising is a preliminary...  相似文献   
942.
Virtual Reality - Artificial intelligence models can produce powerful predictive computer vision tools for healthcare. However, their development simultaneously requires computational skill as well...  相似文献   
943.

Supercapacitors are becoming more popular in the field of energy storage day by day. Thanks to their superior features such as fast charge–discharge, high capacities, and stable structures. Especially, supercapacitors designed using biomass as the electrode material are more preferred in this field because they are cheap, abundant, environmentally friendly, high capacity, and have a long cycle life. In this study, two supercapacitor cells were developed using freshwater algae biomass. In the first stage, supercapacitor electrodes were prepared by Co-doped Chlorella vulgaris (Chl-Co), and in the second stage, electrodes were prepared by Co-doped to H3PO4-washed Chlorella vulgaris (Chl-Co-H3PO4). 6 M KOH solution was used as the electrolyte. Electrochemical characterization results of the electrodes were obtained very close to the ideal supercapacitor characteristic. The capacitance values of the Chl-Co electrode were measured as 80 F/g for 1 A/g, but after the activation by H3PO4, the capacitance rose to 169.7 F/g for 1 A/g. The produced electrodes are promising for energy storage in terms of environmental pollution, cost, stability, and capacity.

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Rainfall rates and soil moisture content have been recognized as the most critical parameters in flood forecasts; the former known as forcing and the latter as the state variable. The main objective of this article is the incorporation of antecedent soil moisture information to reduce false flood warnings over Riyadh City, Saudi Arabia. The forcing variable was obtained from the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Real Time (RT) data (3B42RT). Soil moisture (SM) information was obtained from Advanced Microwave Scanning Radiometer (AMSR-E) as the state variable. Long time series SM information (2002–2011) provided Cumulative Distribution Function (CDF) of SM. CDF with 90% was taken as the SM threshold value. Flooding is indicated for rainy dates exceeding the rain thresholds with the previous satellite overpass SM being greater than 90% CDF of the respective month. The methodology removed the false flood warnings substantially when compared to the flood warnings where SM information was absent. The method is robust and simple, and it can be applied on TRMM and AMSR-E follow on missions; like Global Precipitation Measurement (GPM) and Soil Moisture Active Passive (SMAP).  相似文献   
947.
Metallurgical and Materials Transactions A - Boron-substituted LiCrO2 battery cathode material samples were investigated by X-ray-based techniques to probe the influence of boron on their crystal...  相似文献   
948.
Wind speed prediction (WSP) is essential in order to predict and analyze efficiency and performance of wind-based electricity generation systems. More accurate WSP may provide better opportunities to design and build more efficient and robust wind energy systems. Precious short-term prediction is difficult to achieve; therefore several methods have been developed so far. We notice that the statistics of the alterations, which occur between sequential values of the predicted wind speed data, may differ significantly from observed wind statistics. In this study, we investigate these alterations and compare them and, accordingly, propose a novel method based on Weibull and Gaussian probability distribution functions (PDF) for short-term WSP. The proposed method stands on an algorithm, which examines comparison of the statistical features of the observed and generated wind speed in order to achieve more accurate estimation. We have examined this method on the wind speed data set observed and recorded in Ankara in 2013 and in 2014. The obtained results show that the new algorithm provides better wind speed prediction with an enhanced wind speed model.  相似文献   
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This paper presents the effect of elevated temperatures up to 700 °C on compressive strength and water absorption of two alkali‐activated aluminosilicate composites (one of them is river sand aggregate geopolymer concrete; the other one is crushed sand aggregate geopolymer concrete) and ordinary Portland cement based concretes. To obtain binding geopolymer material, Elaz?? ferrochrome slag was ground as fine as cement, and then it was alkali activated with chemical (NaOH and Na2SiO3). Geopolymer concrete samples were produced by mixing this binding geopolymer material with aggregates. At each target temperature, concrete samples were exposed to fire for the duration of 1 h. Fire resistance and water absorption of geopolymer and ordinary Portland cement concrete samples were determined experimentally. Experimental results indicated that compressive strength of geopolymer concrete samples increased at 100 °C and 300 °C temperatures when compared with unexposed samples. In geopolymer concrete samples, the highest compressive strength was obtained from river aggregates ones at 300 °C with 37.06 MPa. Water absorption of geopolymer concrete samples increased at 700 °C temperature when compared with unexposed samples. However, a slight decrease in water absorption of concrete samples was observed up to 300 °C when compared with unexposed samples. SEM and X‐ray diffraction tests were also carried out to investigate microstructure and mineralogical changes during thermal exposure. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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