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61.
Yields, water use efficiency and economic returns (net farm revenues) of biomass sorghum [Sorghum bicolor (L.) Moench] were investigated over two years (2012 and 2014) under limited water resource conditions. Energy sorghum was grown under four water supply regimes: rain-fed (or dry-land, level 1), 50% (level 2), 75% (level 3) and 100% (level 4) of crop evapotranspiration rates (% ETc). Biomass yields ranged from 5.8 to 16.6 Mg ha−1 (dry weight) after 126 days of growth. Average water use efficiencies ranged from 3.95 kg m−3 to 23.4 kg m−3. Net return was approximately 410 $ ha−1 with water depths above 400 ha-mm. These results suggest that it is possible to obtain more than 60 Mg ha−1 of sorghum biomass (wet basis) with at least 425 mm of water. While biomass yield under irrigation was greater than rain-fed conditions, there were no significant differences among irrigation treatments. Biomass chemical composition did not differ significantly among water treatments suggesting that biofuel quality would not be affected by water deficits. 相似文献
62.
Lanthanum manganite (LaMnO3) nanofibers were synthesized using electrospinning technique. The size and uniformity of these nanofibers were optimized by varying PVP concentration. X-ray diffraction analysis revealed the formation of single phase LaMnO3 nanofibers (average diameter ~400 nm) when the composite nanofibers were calcined at 600 °C. M″ and Z″ spectroscopic plots of impedance spectroscopy data confirmed the presence of two distinct electro-active regions referred to as the grain and grain boundary regions. The activation energies of the grain and grain boundary regions were 0.27 eV and 0.41 eV, respectively; which suggested two different transport mechanisms in these fibers. 相似文献
63.
Jun-Shuw Lin 《Applied Soft Computing》2012,12(6):1733-1740
The clustering phenomenon of defects usually occurs in semiconductor manufacturing. However, previous studies did not pay much attention to the influence of clustering phenomenon for estimating fraction nonconforming of a wafer. Thus, this paper presents a systematic estimation model with considering relevant variables about clustering defects for fraction nonconforming of a wafer. The method combines back-propagation neural network (BPNN) with genetic algorithm (GA) to obtain an estimation model. In this study, GA aims to optimize the parameters of BPNN. Five relevant variables: number of defects (ND), squared coefficient of angle variation (SCVA) for defects, squared coefficient of distance variation (SCVD) for defects, defect cluster index (CIM), and the number of cluster groups (NCG) for defects by self-organized map (SOM) are utilized as inputs for GA–BPNN. Finally, a simulation case and a real-world case are used to confirm the effectiveness of proposed method. 相似文献
64.
The moisture contents of coals are often too high and need to be reduced before further processing. In this study, the application of microwave radiation as an alternative energy source for the drying of a sub-bituminous coal was investigated. Firstly, the permittivities of the coal were evaluated as a function of temperature and frequency. Secondly, the drying kinetics were studied in a 2.45 GHz microwave system and the effects of incident microwave power, sample mass and initial moisture contents were determined. The results demonstrated that microwave drying had several advantages over conventional drying such as increased drying rates and lower final moisture contents. In some tests, magnetite was added as a susceptor to increase the drying rates. Thirdly, the drying data were fitted to ten exponential decay models, and although reasonable agreement was observed with all the models, the best fit was obtained with the Midilli–Kucuk model. Finally, the effective diffusion coefficients of moisture and also the activation energy of the diffusion process were estimated and used to further elucidate the mechanism of microwave drying. 相似文献
65.
Building conceptual sewer models can be a time-consuming task, especially for large or complex models or models that require input data that might be difficult/tedious to obtain manually.This paper presents a semi-automated procedure for the buildup and calibration of one conceptual model that requires detailed input data such as throttle dimensions, pump curves or water level-storage relations. The procedure uses a hydrodynamic model as basis for sewer network data to create the model layout. A standardised series of composite rainfall events is applied to the hydrodynamic model in order to obtain the necessary reference data for the automated calibration of the conceptual model.Both model buildup and calibration are illustrated by means of a case study. Comparison of results of the hydrodynamic and conceptual model for a 1 year long-term series shows that the automated buildup and calibration can lead to an accurate conceptual model in short time. 相似文献
66.
One of the long-lasting challenges of the Architecture, Engineering and Construction (AEC) industry has been addressing personalised solutions as nearly affordable as possible to what could be offered by mass production in the post industrialisation era. Ever since its gestation, BIM has promised endless prospects for people, organisations, products and processes in the AEC industry. This paper sets out to investigate the benefits of BIM as a general configurator to facilitate customisation: offering personalised solutions at a price comparable to mass produced products and services. Providing a quick review of literature, the paper sets the scene for investigating how the generic capabilities of BIM applications can be utilised to offer customisable façade systems. Using a systemic approach, this is then used to elucidate future developments of the current project into next stages where other elements and parameters can be implanted into the basic family to broaden the choice and to reinforce this customisable façade solution. 相似文献
67.
Experimental results are presented concerning the zonal and total discharge distribution and characteristics in a compound channel cross-section comprising one rectangular main channel and two symmetrical floodplains. The discharges in the main channel, floodplains, and total compound channel are found to be highly correlated to several dimensionless parameters defined using the compound channel cross-section geometry. Multi-variable regression analysis was utilized for developing predictive models that can estimate the main channel, floodplains and total discharges as a function of four different dimensionless parameters. The developed models to predict the zonal and total discharges in compound channels are found to be highly significant according to several major statistics including the model standard error, coefficient of determination (R2), and F-statistic. The developed multi-variable regression-based models are also tested for validity using available experimental data. Several statistical tests applicable to the analysis of residuals have indicated the effectiveness of the developed predictive models. 相似文献
68.
The thermal properties of the shape-stabilized phase change material walls with different structure were studied. The phase change material is composed of paraffin mixture and high-density polyethylene. The walls including concrete and shape-stabilized phase change material were prepared respectively by different methods. Preparation methods include direct mixing method and lamination interpolation method. Heat transfer process in the shape-stabilized PCM walls was studied by comparing with traditional wall. The results showed that the surface temperature and the heat flow through the phase change material walls prepared by different methods are lower than that of traditional wall and the change is small. Energy-saving effect of the shape-stabilized PCM walls prepared by lamination interpolation method is better than that of the shape stabilized PCM walls by direct mixing. Results in this paper can provide the basis for the application of the shape stabilized PCM walls in the buildings. 相似文献
69.
《Energy Policy》2016
The purpose of this paper is to estimunate the impact of energy saving investment in residential and public buildings in Croatia for the period 2015–2020. The aim is to assess the overall socio-economic impact of energy saving renovation measures defined in Croatian strategic documents in terms of the direct, indirect and induced growth of gross value added, employment and government revenues. An estimate of the avoided costs of air pollution is also included. The overall economic impact assessment is based on an input-output methodology. From the point of view of individual investors, the benefits in terms of reduced future expenses related to energy products are usually below energy efficient renovation investment costs, making an investment financially viable only if government support is provided. If the benefits for society as a whole are included, energy efficient renovation could be assessed as viable even in the short-run. Energy saving retrofits of residential and public buildings positively contribute to economic growth, employment and protection of the environment. Because of economic growth, the tax revenues induced by these investments could compensate for government expenditures, and the overall impact on the public deficit is expected to be neutral even in the short-run. 相似文献
70.
炭黑废水的处理现状与发展 总被引:1,自引:0,他引:1
主要阐述了炭黑废水的产生,危害和几种处理方法以及炭黑处理新的发展趋势。回收的炭黑可以变废为宝,重新被利用。 相似文献