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91.
Our analysis of the microwave dielectric properties of the δ-Bi2 O3 –Nb2 O5 solid solution (δ-BNss ) showed a continuous increase in permittivity and dielectric losses with an increasing concentration of Nb2 O5 . The only discontinuity was found for the temperature coefficient of resonant frequency, which is negative throughout the entire homogeneity range but reaches a minimum value for the sample with 20 mol% Nb2 O5 . At the same composition there is a discontinuity in the grain size of the δ-BNss ceramics. For the sample containing 25 mol% Nb2 O5 two structural modifications were observed. A single-phase tetragonal Bi3 NbO7 , in the literature referred to as a Type-III phase, is formed in a very narrow temperature range from 850° to 880°C. A synthesis performed below or above this temperature range resulted in the formation of the end member of the δ-BNss homogeneity range. Compared with the δ-BNss the Bi3 NbO7 ceramics exhibit lower microwave dielectric losses, an increased conductivity, and a positive temperature coefficient of resonant frequency. 相似文献
92.
Alain Garnier Claude Chavarie Gerald Andre Danilo Klvana 《Chemical Engineering Communications》1990,98(1):31-45
The inverse fiuidization airlift bioreactor offers a simple solution to the problem of handling shear sensitive cultures and/or systems requiring biofilm growth control. This unit combines in a single vessel the hydrodynamic behavior of concentric tube airlift aerators or contactors and liquid-solid fluidized beds. The effects of the diameter of the concentric tubes, liquid level, bed properties and gas flow rate on gas holdup, bed expansion and liquid circulation velocity were investigated in this study. The Zuber and Findlay relation (1965) gives satisfactory results for gas holdup. The inverse bed expansion can be predicted by the Richardson and Zaki correlation (1953). The liquid circulation velocity can be calculated using a mechanical energy balance 相似文献
93.
Alex Villazón Walter Binder Philippe Moret Danilo Ansaloni 《Science of Computer Programming》2011,76(11):1015-1036
Aspect-oriented programming (AOP) has been successfully applied to application code thanks to techniques such as Java bytecode instrumentation. Unfortunately, with existing AOP frameworks for Java such as AspectJ, aspects cannot be woven into the standard Java class library. This restriction is particularly unfortunate for aspects that would benefit from comprehensive aspect weaving with complete method coverage, such as profiling or debugging aspects. In this article we present MAJOR, a new tool for comprehensive aspect weaving, which ensures that aspects are woven into all classes loaded in a Java Virtual Machine, including those in the standard Java class library. MAJOR includes the pluggable module CARAJillo, which supports efficient access to a complete and customizable calling context representation. We validate our approach with three case studies. Firstly, we weave existing profiling aspects with MAJOR which otherwise would generate incomplete profiles. Secondly, we introduce an aspect for memory leak detection that also benefits from comprehensive weaving. Thirdly, we present an aspect subsuming the functionality of ReCrash, an existing tool based on low-level bytecode instrumentation techniques that generates unit tests to reproduce program failures. Our aspect-based tools are concisely implemented in a few lines of code, and leverage MAJOR and CARAJillo for comprehensive aspect weaving and for efficient access to calling context information. 相似文献
94.
Danilo Horta 《Theoretical computer science》2011,412(42):5854-5870
This paper is concerned with the computational efficiency of fuzzy clustering algorithms when the data set to be clustered is described by a proximity matrix only (relational data) and the number of clusters must be automatically estimated from such data. A fuzzy variant of an evolutionary algorithm for relational clustering is derived and compared against two systematic (pseudo-exhaustive) approaches that can also be used to automatically estimate the number of fuzzy clusters in relational data. An extensive collection of experiments involving 18 artificial and two real data sets is reported and analyzed. 相似文献
95.
Tomasz M. Rutkowski Andrzej Cichocki Danilo P. Mandic Toyoaki Nishida 《AI & Society》2011,26(3):301-315
The paper reports our research aiming at utilization of human interactive communication modeling principles in application
to a novel interaction paradigm designed for brain–computer/machine-interfacing (BCI/BMI) technologies as well as for socially
aware intelligent environments or communication support systems. Automatic procedures for human affective responses or emotional
states estimation are still a hot topic of contemporary research. We propose to utilize human brain and bodily physiological
responses for affective/emotional as well as communicative interactivity estimation, which potentially could be used in the
future for human–machine/environment interaction design. As a test platform for such an intelligent human–machine communication
application, an emotional stimuli paradigm was chosen to evaluate brain responses to various affective stimuli in an emotional
empathy mode. Videos with moving faces expressing various emotional displays as well as speech stimuli with similarly emotionally
articulated sentences are presented to the subjects in order to further analyze different affective responses. From information
processing point of view, several challenges with multimodal signal conditioning and stimuli dynamic response extraction in
time frequency domain are addressed. Emotions play an important role in human daily life and human-to-human communication.
This is why involvement of affective stimuli principles to human–machine communication or machine-mediated communication with
utilization of multichannel neurophysiological and periphery physiological signals monitoring techniques, allowing real-time
subjective brain responses evaluation, is discussed. We present our preliminary results and discuss potential applications
of brain/body affective responses estimation for future interactive/smart environments. 相似文献
96.
Bruno V. L. Siqueira Bruno E. Soares Danilo R. de Oliveira Cássia M. Sakuragui 《Scientometrics》2017,110(2):945-966
In the last three decades, several vernacular names of medicinal plants related to manufactured drugs names have been recognized in ethnobotanical surveys throughout Brazil. The medicalization may be the primarily responsible process for the rise of that type of vernacular names of Brazilian medicinal plants differentially for each geopolitical region of Brazil. We attempt to trace the regionalization of medicalization on vernacular names of medicinal plants through ethnobotanical studies carried out in Brazil since the 1980s. Articles were consulted in nine journals published between 1980 and 2014. Richness estimation by Jackknife 1 and correspondence analysis by contingency tables were performed, both by the occurrence of medicalized names collected in the surveys for each region. The South region presented the highest number of reported and estimated medicalized names, in addition to present the highest number of medicalized names in exclusive occurrence. Northeast and Southeast regions presented a great similarity of medicalized names probably due to the migration flows occurring in both regions over the twentieth century. 相似文献
97.
Giovanni Condello Paolo Pasteris Danilo Pau Mariagiovanna Sami 《Signal Processing: Image Communication》2013,28(4):345-350
Nowadays visual search is one of the most active branches of computer vision. It relies on finding invariant points inside images, describing them into features and then matching these features against a reference database to identify objects in the scene or the entire photo (environment). In this paper, we discuss an approach to feature matching that exploits the capabilities of modern GPUs to speed up the aforementioned and that keeps low the number of false matches. 相似文献
98.
In striving to achieve autonomous navigation, the guidance system plays an essential role. In this article, the authors present two recently developed vision-based methods to estimate the heading angle of the vehicle. The authors propose a real-time guidance application based on edge and color information using an omnidirectional image. First, line segments were extracted. Second, the Random Sample Consensus (RANSAC) curve fitting method was implemented. Third, the set of intersection points for each pair of curves was extracted. Finally, by implementing the Density Based Spatial Clustering of Applications with Noise (DBSCAN) algorithms, the heading angle was computed. The main contribution of this work is in the evaluation of the methods applied, which included the “edge-based extraction in road scenes” method, which uses the spatial density information around the vehicle (curbs, barrier, gutters, side strip areas), and the “edge-based lane marking segmentation.” Both of these methods were evaluated in terms of the performance assessment of the length of the line segments in relation to the heading angle measurement. In that sense, the experiments were conducted for the purpose of testing the processing time and the number of extracted line segments. The preliminary results were gathered and tested on a group of consecutive frames to demonstrate the effectiveness of the proposed methods. 相似文献
99.
100.
Danilo Landrock Barbara P. Atshaves Avery L. McIntosh Kerstin K. Landrock Friedhelm Schroeder Ann B. Kier 《Lipids》2010,45(7):567-580
Unique among the intracellular lipid binding proteins, acyl-CoA binding protein (ACBP) exclusively binds long-chain fatty
acyl-CoAs (LCFA-CoAs). To test if ACBP is an essential protein in mammals, the ACBP gene was ablated by homologous recombination
in mice. While ACBP heterozygotes appeared phenotypically normal, intercrossing of the heterozygotes did not produce any live
homozygous deficient (null) ACBP(−/−) pups. Heterozygous and wild type embryos were detected at all post-implantation stages, but no homozygous ACBP-null embryos
were obtained—suggesting that an embryonic lethality occurred at a pre-implantation stage of development, or that embryos
never formed. While ACBP-null embryos were not detected at any blastocyst stage, ACBP-null embryos were detected at the morula
(8-cell), cleavage (2-cell), and zygote (1-cell) pre-implantation stages. Two other LCFA-CoA binding proteins, sterol carrier
protein-2 (SCP-2) and sterol carrier protein-x (SCP-x) were significantly upregulated at these stages. These findings demonstrate
for the first time that ACBP is an essential protein required for embryonic development and its loss of function may be initially
compensated by concomitant upregulation of two other LCFA-CoA binding proteins, but only at the earliest pre-implantation
stages. The fact that ACBP is the first known intracellular lipid binding protein whose deletion results in embryonic lethality
suggests its vital importance in mammals. 相似文献