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11.
Stefania Grzeszczyk 《Cement and Concrete Research》1986,16(6):798-804
This paper reports upon the research into the influence of sodium ions on C12A7. The actual research work consisted in synthesizing C12A7, treated with the sodium ions as Na2CO3, within the sodium concentration range of up to 25% Na2O by weight in C12A7. The resultant combinations have been identified by the X-ray analysis, the infra-red spectroscopy and the quantitative chemical analysis.
The identification procedure together with the analysis of free CaO content in the products of C12A7 sodium synthesis gave evidence that sodium which is introduced into the researched amount of C12A7 up to 10% Na2O by weight, contributes to the formation of the ever increasing phase of the solid solutions of Na2O in C3A. The continued increase of the sodium volume ( 15% Na2O by weight ) makes it resolve gradually into sodium aluminate β -NA and free CaO. 相似文献
12.
Alfonso Ranalli Luciano Pollastri Stefania Contento Emilia Iannucci Lucia Lucera 《European Journal of Lipid Science and Technology》2003,105(2):57-67
The influence of the olive paste malaxation time on the composition and the industrial output of oil was investigated. To this purpose, three Italian olive varieties (Leccino, Dritta, Caroleo) were processed with a centrifugal system for six malaxation periods (0, 15, 30, 45, 60 and 75 min). The concentrations of the majority of the oil constituents changed during the malaxation. However, these changes were not significant for all of them: the contents of β‐carotene, the major xanthophylls, chlorophylls a and b, pheophytins a and b in the oils increased progressively with increasing malaxing times, whereas the contents of simple and hydrolysable phenols (secoiridoid derivatives), o‐diphenols and total phenols decreased. A significant increase in total volatiles and green volatiles of the lipoxygenase cascade (C6 aldehydes, C6 alcohols, C5 alcohols and C5 carbonyls) was detected. An opposite trend was observed for the green C6 esters. As a result, the global analytical quality, flavour, aroma and shelf‐life of the oils were negatively affected. The oil yield increased substantially up to 45 min of paste malaxation times. Beyond 60 min, the yields tended to decrease. 相似文献
13.
Stefania Vichi Lorena Pizzale Lanfranco S. Conte 《European Journal of Lipid Science and Technology》2007,109(1):72-78
The positional distribution of fatty acids (FA) in triacylglycerols (TAG) of 47 virgin olive oils from diverse cultivars grown in distinct areas of North‐Eastern Italy was studied. Few data were previously available on oils from these geographical areas. The effects of climatic and geographical conditions on the stereospecific distribution of TAG in olive oil were confirmed. Moreover, the results of the stereospecific analysis were used to evaluate the preferential esterification position of each FA on the basis of the degree of unsaturation and the chain length. The data of the stereospecific analysis of olive oil TAG can contribute to the determination of the selectivity of olive fruit acyltransferases for distinct FA. 相似文献
14.
The purpose of this study is to analyze the political economy of food-water security in the water-scarce Middle East and North Africa region. The study deploys the lens of virtual water trade to determine how the region's economies have met their rising food-water requirements over the past three decades. It is shown that the region's water and food security currently depend to a considerable extent on water from outside the region, ‘embedded’ in food imports and accessed through trade. The analysis includes blue (surface and groundwater) and green water resources. 相似文献
15.
Stefania Perri Pasquale Corsonello Giuseppe Cocorullo 《Computer Vision and Image Understanding》2013,117(1):29-41
This paper presents a new hardware-oriented approach for the extraction of disparity maps from stereo images. The proposed method is based on the herein named Adaptive Census Transform that exploits adaptive support weights during the image transformation; the adaptively weighted sum of SADs is then used as the dissimilarity metric. Quality tests show that the proposed method reaches significantly better accuracy than alternative hardware-oriented approaches. To demonstrate the practical hardware feasibility, a specific architecture has been designed and its implementation has been carried out using a single FPGA chip. Such a VLSI implementation allows a frame rate up to 68 fps to be reached for 640 × 480 stereo images, using just 80,000 slices and 32 RAM blocks of a Virtex6 chip. 相似文献
16.
Exploring new roles for case-based reasoning in heterogeneous AI systems for medical decision support 总被引:2,自引:2,他引:0
Stefania Montani 《Applied Intelligence》2008,28(3):275-285
Background Supporting medical decision making is a complex task, that offers challenging research issues to Artificial Intelligence
(AI) scientists. The Case-based Reasoning (CBR) methodology has been proposed as a possible means for supporting decision
making in this domain since the 1980s. Nevertheless, despite the variety of efforts produced by the CBR research community,
and the number of issues properly handled by means of this methodology, the success of CBR systems in medicine is somehow
limited, and almost no research product has been fully tested and commercialized; one of the main reasons for this may be
found in the nature of the problem domain, which is extremely complex and multi-faceted.
Materials and methods In this environment, we propose to design a modular architecture, in which several AI methodologies cooperate, to provide
decision support. In the resulting context CBR, originally conceived as a well suited reasoning paradigm for medical applications,
can extend its original roles, and cover a set of additional tasks.
Results and conclusions As an example, in the paper we will show how CBR can be exploited for configuring the parameters relied upon by other (reasoning)
modules. Other possible ways of deploying CBR in this domain will be the object of our future investigations, and, in our
opinion, a possible research direction for people working on CBR in the health sciences. 相似文献
17.
Kirsten Bobzin Erich Lugscheider Felix Ernst Reimo Nickel Nazlim Bagcivan Daniel Parkot Arne Schlegel Stefania Ferrara Tatyana Kashko Noémi Leick 《Microsystem Technologies》2008,14(12):1887-1894
Nowadays, micro components have to fulfill rising optical requirements for different scientific and industrial fields like
astronomy, medicine or multimedia. For this purpose, advanced miniaturized chip-cameras are produced for the microsystems
engineering market. The assembly and joining technologies play a very important role in the production of these micro components.
Several challenges are associated with the joining of chip-cameras. In this study, the application of the soldering technology
has been considered in order to face these challenges. Two joining technologies have been investigated: active soldering and
transient liquid phase (TLP) bonding. Both soldering processes have shown a big potential for hybrid microsystems joining
in previous studies. For both processes, soldering alloys and parameters have been conceived in order to fulfill the joining
requirements of the micro camera components. For instance, the joining temperature represents a major challenge because the
chip-camera consists of a plastic material, polymethyl methacrylate (PMMA). Therefore, particular attention has been directed
to the soldering as well as to the coating temperature. The experimental investigations concerning the solders application
through physical vapor deposition (PVD) have been supported by finite element method (FEM) simulations. The analysis of the
temperature distribution in the micro components during the coating process was the focus of the calculations. Possible undesirable
local overheated areas of the chip-camera components can be detected through simulation.
相似文献
Tatyana KashkoEmail: |
18.
Trotta Gianluca Cacace Stefania Semeraro Quirico 《Journal of Intelligent Manufacturing》2022,33(7):2045-2057
Journal of Intelligent Manufacturing - In industrial research, experiments are designed to determine the optimal factor levels of the process parameters. Typically, experimental data are used to... 相似文献
19.
20.
Complementarities between technological and non-technological innovation are crucial determinants of firm performance. Although innovation complementarity has been extensively tested in the empirical literature, it has not been analysed in conjunction with innovation persistence. This fact is mainly due to the lack of data sets able to provide adequate longitudinal information. The capacities to develop market-oriented behaviour and introduce new organisational innovations, together with technological innovation, are the drivers of a firm’s productivity and profitability. We find that these activities complement technological innovation and that their impact is greater when they persist over time, thus introducing a more general concept of innovation persistence. We present an empirical model based on a large new panel of Italian manufacturing firms covering the period 2000–2012 which enables us to determine the precise impacts of a firm’s innovative attitude, in a broad definition that incorporates non-technological innovation and persistence, on its productivity and profitability. 相似文献