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Multimedia Tools and Applications - Mobile devices have become a commodity in nowadays allowing people to get connected and perform several tasks for work. The usefulness of mobile is mobility...  相似文献   
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Recently, demand increased for dielectric materials used in energy storage devices at high voltage applications. Appearance of polar clusters in glass matrix could promote its use in energy storage applications. Conventional quenched glass sample of composition 10PbTiO3–10Fe2O3–30V2O5–50B2O3 were successfully developed. The glassy nature was confirmed by XRD and DSC measurements. Boson peak observed at low frequency from the Raman spectra confirms polar cluster formation. Dielectric properties of prepared glass were investigated in a wide range of frequency and temperature. Broad and diffuse peak of dielectric permittivity shifted to the higher temperatures, denoting the typical relaxor ferroelectrics like behavior. Sample shows energy storage density of about 164.7 mJ/cm3 at room temperature. Quenched glass sample shows typical anti-ferromagnetic behavior.

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Gross CO2 and CH4 emissions (degassing and diffusion from the reservoir) and the carbon balance were assessed in 2009-2010 in two Southeast Asian sub-tropical reservoirs: the Nam Ngum and Nam Leuk Reservoirs (Lao PDR). These two reservoirs are within the same climatic area but differ mainly in age, size, residence time and initial biomass stock. The Nam Leuk Reservoir was impounded in 1999 after partial vegetation clearance and burning. However, GHG emissions are still significant 10 years after impoundment. CH4 diffusive flux ranged from 0.8 (January 2010) to 11.9 mmol m− 2 d− 1 (April 2009) and CO2 diffusive flux ranged from - 10.6 (October 2009) to 38.2 mmol m− 2 d− 1 (April 2009). These values are comparable to other tropical reservoirs. Moreover, degassing fluxes at the outlet of the powerhouse downstream of the turbines were very low. The tentative annual carbon balance calculation indicates that this reservoir was a carbon source with an annual carbon export (atmosphere + downstream river) of about 2.2 ± 1.0 GgC yr− 1.The Nam Ngum Reservoir was impounded in 1971 without any significant biomass removal. Diffusive and degassing CO2 and CH4 fluxes were lower than for other tropical reservoirs. Particularly, CO2 diffusive fluxes were always negative with values ranging from - 21.2 (April 2009) to - 2.7 mmol m−2 d−1 (January 2010). CH4 diffusive flux ranged from 0.1 (October 2009) to 0.6 mmol m−2 d−1 (April 2009) and no degassing downstream of the turbines was measured. As a consequence of these low values, the reservoir was a carbon sink with an estimated annual uptake of - 53 ± 35 GgC yr−1.  相似文献   
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In the machine learning (ML) paradigm, data augmentation serves as a regularization approach for creating ML models. The increase in the diversification of training samples increases the generalization capabilities, which enhances the prediction performance of classifiers when tested on unseen examples. Deep learning (DL) models have a lot of parameters, and they frequently overfit. Effectively, to avoid overfitting, data plays a major role to augment the latest improvements in DL. Nevertheless, reliable data collection is a major limiting factor. Frequently, this problem is undertaken by combining augmentation of data, transfer learning, dropout, and methods of normalization in batches. In this paper, we introduce the application of data augmentation in the field of image classification using Random Multi-model Deep Learning (RMDL) which uses the association approaches of multiDL to yield random models for classification. We present a methodology for using Generative Adversarial Networks (GANs) to generate images for data augmenting. Through experiments, we discover that samples generated by GANs when fed into RMDL improve both accuracy and model efficiency. Experimenting across both MNIST and CIAFAR-10 datasets show that, error rate with proposed approach has been decreased with different random models.  相似文献   
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In‐stream habitat enhancement is a common remedial action in rivers where degradation/lack of suitable fish habitat can be diagnosed. However, post‐project monitoring to assess the response of the biota to modification is rare particularly during winter. We conducted in situ monitoring during the winters of 2004–2006 in the regulated Dalåa River, central Norway, in order to determine if winter habitat requirements of Atlantic salmon (Salmo salar L.) parr were realized in an enhanced (substrate and mesohabitat modification) reach. In total, 140 parr were marked with passive integrated transponder (PIT) tags and the fish were followed by carrying out active tracking surveys under variable ice conditions throughout the winter. Highest emigration (44%) occurred before ice formation started. Emigration was reduced after ice formed and was largely offset by parr re‐entering the enhanced area. Dispersal into the non‐enhanced, small substrate control area was observed only when the study reach was ice covered, and no parr were subsequently encountered in the control section after ice had melted. In the enhanced area, declining water temperature and surface ice conditions did not affect the spatial distribution of the resident salmon parr at the studied scale. Areas with ‘solid’ anchor ice precluded access for salmon parr whilst areas with ‘patchy’ anchor were used throughout the winter. Our results indicate that surface ice creates conditions that allow salmon parr to use stream habitats that otherwise provide only a limited amount of in‐stream cover. Ice processes should be taken into consideration when habitat enhancement projects are carried out and subsequently assessed for effectiveness. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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Climate change asks for the reduction in the consumption of fossil‐based fuels and an increased share of non‐regulated renewable energy sources, such as solar and wind power. In order to back up a larger share of these intermittent sources, ‘battery services’ are needed, currently provided only in large scale by hydropower, leading to more rapid and frequent changes in flows (hydropeaking) in the downstream rivers. Increased knowledge about the ecosystem response to such operations and design of cost‐effective measures is needed. We analysed the response of fish communities to hydropeaking (frequency, magnitude, ramping rate and timing) and the interaction with the habitat conditions in Austrian rivers. An index of biotic integrity (Fish Index Austria) was used to compare river sections with varying degrees of flow fluctuations under near‐natural and channelized habitat conditions. The results showed that habitat conditions, peak frequency (number of peaks per year), ramping rate (water level variation) and interaction between habitat and ramping rate explained most of the variation of the Fish Index Austria. In addition, peaking during the night seems to harm fish more than peaking during the day. Fish communities in hyporhithral and epipotamal types of rivers are more affected by hydropeaking than those in metarhithral type of rivers. The results support the findings of other studies that fish stranding caused by ramping rates >15 cm h?1 are likely to be the main cause of fish community degradation when occurring more often than 20 times a year. While the ecological status degrades with increasing ramping rate in nature‐like rivers, fish communities are heavily degraded in channelized rivers regardless of the ramping rate. The mitigation of hydropeaking, therefore, requires an integrative approach considering the combined effects of hydrological and morphological alterations on fish. © 2014 The Authors. River Research and Applications published by John Wiley & Sons, Ltd.  相似文献   
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Animal glue has been used to fix historical textiles on paper, wood panels, or other rigid support materials. It is often present in shrunk, cracked, rigid, and brittle form because of the aged condition artifacts and may not provide enough adhesion for effective support causing damage to historical textiles. The biotechnological application of enzymes seems to be a very promising approach in the restoration of historical objects. In this experimental work, undertaken with modern linen and silk fabrics, interesting results have been obtained for the removal of animal glue by using the protease enzyme from Aspergillus oryzae. An extensive study was done in the enzymatic activity and efficiency for the removal of the animal glue from the textiles, as well as the effects of this treatment on mechanical and optical parameters of the textile fibers. The effect of protease on fibers is measured by Fourier transform infrared spectral analysis, scanning electron microscope, the CIE‐Lab values, ASTM method D5035, and XRD. The results showed that using protease in adhesive removal presented good results with a safe and a short treatment time when compared with the conventional methods. No significant changes on the linen and silk fabrics are observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
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This article proposes and demonstrates a new classification system of fish population level effects of hydropeaking operations in rivers. The classification of impacts is developed along two axes; first, the hydromorphological effect axis assesses the ecohydraulic alterations in rivers introduced by rapid and frequent variations in flow and water level, second the vulnerability axis assesses the site-specific vulnerability of the fish population. Finally, the population level impact is classified into four classes from small to very large by combining the two axes. The system was tested in four rivers in Norway exposed to hydropeaking, and they displayed a range of outcomes from small to very large impacts on the salmon populations. The river with a relatively high base flow and ramping restrictions scored better than rivers with the lower base flow or limited ramping restrictions, indicating that hydropeaking effects can be mitigated while maintaining high hydropower flexibility. Most effect factors could easily be calculated from timeseries of discharge and water level, whereas the use of hydraulic models to estimate potential stranding areas may require more work. The vulnerability factors are mainly qualitative and depend more heavily on expert judgments and are thus more uncertain. The system was deemed suitable for the purpose of supporting management decisions for rivers exposed to hydropeaking operations. It evaluates the severity of the additional pressures due to hydropeaking operations and proved useful to identify mitigating measures. While the system was developed for Atlantic salmon river systems, it could be adapted to other species or systems.  相似文献   
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An increase in the demand for renewable energy is driving hydropower development and its integration with variable renewable energy sources. When hydropower is produced flexibly from hydropower plants, it causes rapid and frequent artificial flow fluctuations in rivers, a phenomenon known as hydropeaking. Hydropeaking and associated hydrological alterations cause multiple impacts on riverine habitats with cascading effects on ecosystem functioning and structure. Given the significance of its ecological and socio-economic implications, mitigation of hydropeaking requires an inter- and transdisciplinary approach. An interdisciplinary network called HyPeak has been conceived to enrich international research initiatives and support hydropower planning and policy. HyPeak has been founded based on exchange and networking activities linking scientists from several countries where hydropeaking has been widespread for decades and numerous studies dedicated to the topic have been carried out. HyPeak aims to integrate members from other countries and continents in which hydropower production plays a relevant role, and grow to be a reference group that provides expert advice on the topic to policy-makers, as well as researchers, stakeholders, and practitioners in the field of hydropeaking.  相似文献   
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