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41.
42.
A Technique for Extracting Sub-source Similarities from Information Sources Having Different Formats
In this paper we propose a semi-automatic technique for deriving the similarity degree between two portions of heterogeneous information sources (hereafter, sub-sources). The proposed technique consists in two phases: the first one selects the most promising pairs of sub-sources, whereas the second one computes the similarity degree relative to each promising pair. We show that the detection of sub-source similarities is a special case (and a very interesting one, for semi-structured information sources) of the more general problem of Scheme Match. In addition, we present a real example case to clarify the proposed technique, a set of experiments we have conducted to verify the quality of its results, a discussion about its computational complexity and its classification in the context of related literature. Finally, we discuss some possible applications which can benefit by derived similarities. 相似文献
43.
In this paper, the problem of reducing a given LTI system into a left or right invertible one is addressed and solved with the standard tools of the geometric control theory. First, it will be shown how an LTI system can be turned into a left invertible system, thus preserving key system properties like stabilizability, phase minimality, right invertibility, relative degree and infinite zero structure. Moreover, the additional invariant zeros introduced in the left invertible system thus obtained can be arbitrarily assigned in the complex plane. By duality, the scheme of a right inverter will be derived straightforwardly. Moreover, the squaring down problem will be addressed. In fact, when the left and right reduction procedures are applied together, a system with an unequal number of inputs and outputs is turned into a square and invertible system. Furthermore, as an example it will be shown how these techniques may be employed to weaken the standard assumption of left invertibility of the plant in many optimization problems. 相似文献
44.
Domenico Famularo Peter Dorato Chaouki T. Abdallah Wassim M. Haddad Ali Jadbabaie 《International journal of control》2013,86(2):159-165
This paper describes the synthesis of non-fragile or resilient regulators for linear systems. A general framework for fragility is described using state-space methodologies, and the LQ/H2 static state-feedback problem is examined in detail. We discuss the multiplicative structured uncertainties case, and propose remedies of the fragility problem using an optimization programming framework via matrix inequalities. A special case that leads to a convex optimization framework via linear matrix inequalities (LMIs) will be considered. The benchmark problem is taken as an example to show how special controller gain variations can affect the performance of the closed-loop system. 相似文献
45.
The paper presents a neural network model of the touch sensitivity circuit of the nematode Caenorhabditis elegans. We describe a serie of simulations in which neural networks are trained, using a genetic algorithm, to reproduce the habituation of the nematode's touch sensitive behavior. A lesion study of the network allows to make a direct comparison between the fine functioning of the model and the data collected in real organisms. The model accords well with the known neurobiological data and it suggests some hypotheses about the functioning of the neural circuit and of single neurons. 相似文献
46.
Laurà R Magnoli D Zichichi R Guerrera MC De Carlos F Suárez AÁ Abbate F Ciriaco E Vega JA Germanà A 《Microscopy research and technique》2012,75(3):359-366
The zebrafish pineal gland plays a fundamental role in the regulation of the circadian rhythm through the melatonin secretion. The pinealocytes, also called photoreceptive cells, are considered the morphofunctional unit of pineal gland. In literature, the anatomical features, the cellular characteristics, and the pinealocytes morphology of zebrafish pineal gland have not been previously described in detail. Therefore, this study was undertaken to analyze the structure and ultrastructure, as well as the immunohistochemical profile of the zebrafish pineal gland with particular reference to the pinealocytes. Here, we demonstrated, using RT-PCR, immunohistochemistry and transmission electron microscopy, the expression of the mRNA for rhodopsin in the pineal gland of zebrafish, as well as its cellular localization exclusively in the pinealocytes of adult zebrafish. Moreover, the ultrastructural observations demonstrated that the pinealocytes were constituted by an outer segment with numerous lamellar membranes, an inner segment with many mitochondria, and a basal pole with the synapses. Our results taken together demonstrated a central role of zebrafish pinealocytes in the control of pineal gland functions. 相似文献
47.
Annurca (Malus pumila Miller cv. Annurca) apple as a functional food for the contribution to a healthy balance of plasma cholesterol levels: results of a randomized clinical trial 下载免费PDF全文
48.
Controllability of One Spin and Two Interacting Spins 总被引:1,自引:0,他引:1
Mathematics of Control, Signals, and Systems - ?We consider the problem of steering control for the systems of one spin ½ particle and two interacting spin ½ particles in an... 相似文献
49.
Ilias Chlis Domenico Pepe Domenico Zito 《International Journal of Circuit Theory and Applications》2016,44(9):1697-1705
This paper reports a phase noise analysis in a differential Armstrong oscillator circuit topology in CMOS technology. The analytical expressions of phase noise due to flicker and thermal noise sources are derived and validated by the results obtained through SpectreRF simulations for oscillation frequencies of 1, 10, and 100 GHz. The analysis captures well the phase noise of the oscillator topology and shows the impact of flicker noise contribution as the major effect leading to phase noise degradation in nano‐scale CMOS LC oscillators. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
50.
Pietro Russo Giorgio Simeoli Domenico Acierno Valentina Lopresto 《Polymer Composites》2015,36(11):2022-2029
Polyolefin‐based composite laminates reinforced with jute fabric were prepared by compression molding and investigated in terms of flexural properties and impact behavior. The use of a virgin polypropylene as the matrix was compared with two polyolefin matrices coming from discarded car bumpers and selected packaging wastes, respectively, and mainly constituted by mixtures of polyethylene and polypropylene resins. The influence of a coupling agent (maleated polypropylene) was always considered in order to improve the interfacial adhesion and, consequently, the composite strength. The effect of this coupling agent, clearly dependent on the amount of polypropylene phase in the overall mixture, was found to be satisfactory only in the case of virgin polypropylene‐based systems. These latter, in presence of maleated polypropylene, have shown higher flexural parameters, lower propagation energy and higher breaking impact load with respect to uncompatibilized ones. Results were supported by morphological observations of impact surfaces, always highlighting a poor adhesion at the reinforcement–matrix interface except in compatibilized virgin polypropylene‐based laminates. POLYM. COMPOS., 36:2022–2029, 2015. © 2014 Society of Plastics Engineer 相似文献