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排序方式: 共有319条查询结果,搜索用时 15 毫秒
1.
A numerical model of solar cells is described, which provides optimum design rules for exponential N+ dopant profiles for heavily doped emitter regions. The model gives a useful insight into the relative impact of surface and bulk recombination on device performance. Results agree well with theorical models. 相似文献
2.
Exposito A.G. Soler A.B. Macias J.A. 《IEEE transactions on circuits and systems. I, Regular papers》2006,53(7):1533-1543
This paper focuses on the natural response computation of linear time-invariant (LTI) circuits, in those cases in which a closed-form solution, rather than numerical integration of the state-variable equations, is preferable. A computationally efficient procedure is presented to individually obtain the eigenvectors of matrix A, both for distinct and repeated eigenvalues. Instead of performing orthogonal matrix transformations, the proposed method relies on the solution of the nodal equations corresponding to a zero-input circuit in the generalized phasor domain. This allows propagation of natural modes to be computed by means of a simple procedure that closely resembles conventional ac analysis. 相似文献
3.
Jesú s Guardiola Soler Juan J. Prieto Marqu s M nica Garcí a Ruiz Guadalupe Ramos Caicedo 《Chemical Engineering Communications》2003,190(3):285-298
The purpose of the present work is to demonstrate the reliability of a digital image processing technique. A CCD (Charge Coupled Device) is used to perform an investigation on the bubble properties of a 2D gas-solid fluidized bed, and the aim of this study is to establish a criterion in order to reject all images that could not be interpreted as bubbles. This may lead to an alteration of the information obtained. The two-dimensional fluidized bed is 20 cm wide and at least 20 cm high, and the field of view of the camera is 12.54 cm wide and 12.99 cm high. In this way, bubbles could be totally or partially placed into this field of view so that a partial image of a bubble could be analyzed as a whole bubble. With this calibration, a geometric decision criterion for the rejection of nonbubble images was developed. 相似文献
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Xavier Desforges Abdallah Habbadi Laurent Geneste François Soler 《Journal of Intelligent Manufacturing》2004,15(1):39-53
The study of smart sensors and actuators led, during the past few years, to the development of facilities which improve traditional sensors and actuators in a necessary way to automate production systems. In another context, many studies have been carried out aimed at defining a decisional structure for production activity control and the increasing need of reactivity leads to the autonomization of decisional levels close to the operational system. We study in this paper the natural convergence between these two approaches and we propose an integration architecture, dealing with machine tool and machining control, that enables the exploitation of distributed smart sensors and actuators in the decisional system. 相似文献
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M. L. Pacheco J. Soler A. Dejoz J. M. Lpez Nieto J. Herguido M. Menndez J. Santamaría 《Catalysis Today》2000,61(1-4):101-107
Butadiene has been produced from butane by oxidative dehydrogenation on a MoO3/MgO catalyst using a two-zone fluidized bed reactor (TZFBR). The effect of the main TZFBR operating variables was studied, and its performance was compared with that of conventional fluidized beds and fixed bed reactors loaded with the same catalyst. These results have been compared with those obtained on a selective V2O5/MgO catalyst. 相似文献
10.
Olaya Ruiz-Rueda Mar?al Soler Laia Calv�� Jes��s L. Garc��a-Gil 《Food Analytical Methods》2011,4(2):131-138
In this study, we have developed a rapid method for the simultaneous detection of Listeria monocytogenes and Salmonella spp. in foods, combining culture enrichment and a multiplex real-time polymerase chain reaction (PCR). The assay used two
pre-existing primer-probe sets, labelled with different reporter dyes to enable the direct distinction of the original contaminating
agent. Amplification efficiency and inclusivity/exclusivity of the combined assay was successfully assessed. The overall process
included the culture enrichment based on the ISO standard, consisting of 24 h incubation in appropriate media (Half Fraser
Broth for Listeria and buffered peptone water (BPW) for Salmonella), followed by a single DNA extraction of mixed enrichment aliquots, and real-time PCR detection of the hly and bipA genes of L. monocytogenes and Salmonella spp., respectively. An internal amplification control, co-amplified during the PCR run, was included in the assay to verify
the results. The tool was evaluated with a variety of artificially inoculated samples of fresh products and ready to eat and
cooked dishes, allowing the identification of the target pathogens down to 5 CFU/25 g of food sample. Moreover, the analysis
saved a considerable amount of time compared to the ISO standard, being performed in less than 2 working days. Specificity,
sensitivity and accuracy were satisfactorily tested by comparison to the standard methods ISO 11290-2:1998 and ISO 6579:2002,
suggesting that the tool has a great potential as a reliable alternative for food safety assurance providing rapid detection
of both pathogens in food samples. 相似文献