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排序方式: 共有231条查询结果,搜索用时 31 毫秒
91.
92.
Pardo-Giménez A Zied DC Álvarez-Ortí M Rubio M Pardo JE 《Journal of the science of food and agriculture》2012,92(8):1665-1671
BACKGROUND: This work assesses the agronomic performance of grapeseed meal, before and after oil extraction, in nutritional compost supplement when growing the mushroom species Agaricus bisporus (Lange) Imbach. The effect of formaldehyde treatment before using this compost is also considered. Materials were applied at different doses at spawning. Along with non‐supplemented compost, three commercial nutritional supplements were used as controls. RESULTS: In general terms, grapeseed meal performance was similar to that of commercial delayed‐release nutrients, but improved the non‐supplemented compost response. We highlight that grapeseed enhances performance as larger yields of harvested mushrooms were obtained with greater dry weight content; however, their protein content was lower. The best performance was displayed by fresh formaldehyde‐treated grapeseed (6000 ppm) when applied to the 10 g kg?1 compost dose. CONCLUSIONS: Our findings suggest that grapeseed meal offers a great potential to be applied on a commercial scale. The addition of grapeseed resulted in an enhanced performance as shown by the higher number of harvested mushrooms. The use of grapeseed meal (extracted or non‐extracted), a low‐cost ingredient with high levels of carbohydrates, may suppose an economic profit on the basis of the positive effect of adding carbon in the mushroom cultivation. Copyright © 2012 Society of Chemical Industry 相似文献
93.
Alexandre Finke Philippe Poizot Claude Guéry Driss Mazouzi Jean‐Marie Tarascon 《Advanced functional materials》2008,18(22):3598-3605
An Fe3O4/Cu nanostructured prototype electrode was developed from a 100% bottom‐up approach thanks to an original three‐step electrodeposition procedure that enlists 1) the growth of a ZnO nanocolumnar template, 2) the filling of the template voids by copper prior to the dissolution of the zincite nanopillars, and 3) the plating on the remaining copper nanodots of the Fe3O4 phase. The key technological point is that ZnO readily forms nanorod arrays by self‐assembly when an aqueous solution of ZnII, saturated by dioxygen, is cathodically polarized. The as‐obtained inorganic solid template is sufficiently stable for further deposition steps of any kind (metals, oxides, polymers, and so on) but is easy to remove in both acidic and alkaline media. The self‐supported Fe3O4/Cu nanostructured electrode shows, besides sustained capacity retention, outstanding rate capability when electrochemically tested versus Li. This original and soft process, derived from template‐assisted synthesis, avoids fixing (mechanically) a nanoporous membrane on the substrate, thus, enabling nanostructural design on shapeless surfaces. 相似文献
94.
Youness Jouihri Zouhair Guennoun Youssef Chagh Driss Zahi 《Telecommunication Systems》2017,64(3):467-478
The Recent decades have witnessed intensive efforts from operators to implement methods enabling better control over network utilization, service usage, and service monetization. Nevertheless, they report significant growth in Diameter signaling traffic, especially policy management signaling traffic. More specifically, operators offering long term evolution (LTE) data-only services and planning for a massive introduction of voice over LTE (VoLTE) and voice over WiFi (VoWiFi) services need to tackle the enormous growth in Diameter signaling traffic. The biggest challenge for those operators is to find an appropriate solution, scalable enough to handle the unpredictable growth of Diameter signaling traffic; as the VoLTE and VoWiFi services will reshape the landscape of LTE policies. Throughout this paper, we propose a network function virtualization (NFV) based model, mature enough to tackle the challenges of those operators planning to launch VoLTE and VoWiFi, without impacting existing services and without jeopardizing current revenues. In our approach we first used standard VoLTE and VoWiFi message flow and referenced users’ behavior; then we considered NFV architecture characteristics. We finally referred to the latest experiments and test results related to NFV maturity cycle. 相似文献
95.
Khaled Brahmi Wided Bouguerra Hamza Belhsan Elimame Elaloui Mouna Loungou Zied Tlili Béchir Hamrouni 《Mine Water and the Environment》2016,35(3):310-317
This study evaluated electrocoagulation using Al electrodes for removal of non-carbonate hardness in phosphate mining process water. Examination of process parameters identified optimal conditions for hardness removal at pH 7, a NaCl concentration of 4 g/L, a current density of 22.2 mA/cm2, an inter-electrode distance of 2 cm, a stirring speed of 450 revolutions per minute, and a treatment time of 30 min. Production of primary coagulant during electrolysis improved removal of both calcite and magnesium hydroxide. The optimized hardness removal was highly efficient, with an overall removal rate of 83.8 % at 30 min of retention time. 相似文献
96.
In this paper, and from the received waves, we investigate a number of Polarimetric radar techniques to characterize the polarization response of forest cover, using the example of the Landes Forest. Magnitude, as well as phase difference and amplitude ratios between the Polarimetrie channels, which are closely related to the texture of the scene, offer reliable means for data characterization and discrimination purposes. The statistical properties of high resolution Polarimetrie sar are investigated, using the K distribution to model the received amplitude of each area selected. This distribution is derived with a parameter, a, which is closely related to the heterogeneity of the ground cover, and thus provides a good tool for discriminating among different regions. From the Stokes matrix, the co- and crosspola-rized signatures are constructed, for both clear cut and full-grown tree regions, in order to identify the predominant scattering mechanisms contributing to total measured backscatter. 相似文献
97.
Journal of Scheduling - This paper addresses the job shop scheduling problem including time lag constraints. This is an extension of the job shop scheduling problem with many applications in real... 相似文献
98.
Mitchell McLaren Driss Matrouf Robbie Vogt Jean-Francois Bonastre 《Computer Speech and Language》2011,25(2):327-340
This paper presents an extended study on the implementation of support vector machine (SVM) based speaker verification in systems that employ continuous progressive model adaptation using the weight-based factor analysis model. The weight-based factor analysis model compensates for session variations in unsupervised scenarios by incorporating trial confidence measures in the general statistics used in the inter-session variability modelling process. Employing weight-based factor analysis in Gaussian mixture models (GMMs) was recently found to provide significant performance gains to unsupervised classification. Further improvements in performance were found through the integration of SVM-based classification in the system by means of GMM supervectors.This study focuses particularly on the way in which a client is represented in the SVM kernel space using single and multiple target supervectors. Experimental results indicate that training client SVMs using a single target supervector maximises performance while exhibiting a certain robustness to the inclusion of impostor training data in the model. Furthermore, the inclusion of low-scoring target trials in the adaptation process is investigated where they were found to significantly aid performance. 相似文献
99.
R. Rahmani B. Amrani K. Driss Khodja A. Boukhachem P. Aubert 《Journal of Computational Electronics》2018,17(3):920-925
The electronic structure, elastic constants, and magnetic properties of lanthanum cobaltite oxide \(\hbox {La}_{4}\hbox {Co}_{3}\hbox {O}_{9}\) compound, which crystallizes in orthorhombic space group Pnma, are investigated theoretically for the first time using the full potential linearized augmented plane wave (FP-LAPW) method based on the density functional theory plus Hubbard correction term (DFT \(+\) U). The calculated equilibrium lattice constants and fractional atomic coordinates are in a good agreement with available experimental data. Our result for the formation energy and elastic constants confirms that the predicted \(\hbox {La}_{4}\hbox {Co}_{3}\hbox {O}_{9}\) is mechanically stable. This compound is found to be ductile in nature in accordance with Pugh’s criteria. The anisotropy factors (\({A}_{1})\), (\({A}_{2})\), and (\({A}_{3})\) of \(\hbox {La}_{4}\hbox {Co}_{3}\hbox {O}_{9}\) material are also predicted through the elastic constants. The electronic band structures show metallic behavior; the conductivity is mostly governed by Co-3d and O-2p states. The total magnetic moments of the tetrahedral (\(\hbox {CoO}_{4})\) and octahedral (\(\hbox {CoO}_{6})\) environments are, respectively, 2.502 \(\mu _{B}\) and 2.874 \(\mu _{B}\), which are consistent with the experimental measurements. 相似文献
100.
This work treats an industrial problematic of a manufacturing system M1 subject to random failure and that satisfies a random demand under required service level. To ensure the satisfaction of the demand, it calls up on a second manufacturing system M2 that is a subcontractor and has a stochastic service level. This paper aims to determine an optimal production plan taking into account the degradation of the manufacturing system following its production rate and its availability. The unavailability of the machine M1 is due to the non-negligible preventive and corrective maintenance actions duration. To consider a realistic case of the subcontractor, we consider that is not able to respond to the variation of the demand, and then it assumed that the manufacturer can order a minimum fixed quantity. We then derive an optimal production plan taking into account the degradation of the machine and simultaneously minimising: inventory, degradation and production cost. An algorithm based on finite perturbation analysis is proposed to determine the optimal production plan and the sensitivity study of the availability is presented. 相似文献