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11.
DellaGreca M Isidori M Lavorgna M Monaco P Previtera L Zarrelli A 《Journal of chemical ecology》2004,30(4):867-879
Twenty-five 9,10-dihydrophenanthrenes, four phenanthrenes, a dihydrodibenzoxepin, and a pyrene, isolated from the wetland plant Juncus acutus, were tested to detect their effects on the green alga Selenastrum capricornutum. Nine of the compounds were isolated and identified for the first time. Most of the compounds caused inhibition of algal growth. The 9,10-dihydrophenanthrenes 1, 5, 21, and 22 were the most active. 相似文献
12.
Output feedback of Markov jump linear systems with no mode observation: An automotive throttle application
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Alessandro N. Vargas Leonardo Acho Gisela Pujol Eduardo F. Costa João Y. Ishihara João B. R. do Val 《国际强度与非线性控制杂志
》2016,26(9):1980-1993
》2016,26(9):1980-1993
The note presents an output feedback control strategy for Markov jump linear systems with no mode observation. Based on minimizing a finite‐time quadratic cost, we derive an algorithm that generates output feedback gains that satisfy a necessary optimality condition. These gains can be computed off‐line relying only on the initial condition of the system. This result expands a previous one from the literature that considered state‐feedback only. To illustrate the usefulness of the approach, real‐time laboratory experiments were performed to control an automotive electronic throttle valve subject to Markov‐driven voltage fluctuations. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
13.
José Augusto de Oliveira Diogo Aparecido Lopes Silva Mariana Guardia Lillian do Nascimento Gambi Otávio José de Oliveira Aldo Roberto Ometto 《Clean Technologies and Environmental Policy》2017,19(6):1761-1774
The companies’ needs to adopt changes in their way of production to maximize the environmental performance required by their stakeholders, and at the same time, to maximize their economic and market performance, have made them seek for environmental strategies and certifications. In this sense, the Cleaner Production and the Environmental Management System based on ISO 14001 have been, respectively, presented, since the main objective of this research is to identify and analyze Cleaner Production contributions to comply with ISO 14001 requirements. For such, a survey research has been carried out in Brazilian industrial companies certified by ISO 14001. We have identified the main performance factors by leading practices and variables of Cleaner Production that contribute to the compliance with the standard requirements by companies. Thus, it has been noted that Cleaner Production is an important strategy for the preparation of companies for certification as well as for improving their environmental performance. 相似文献
14.
Jens Laube Valentin Baric Samir Salameh Lutz Mädler Lucio Colombi Ciacchi 《Granular Matter》2018,20(2):28
We develop a novel coarse-grained contact model for Discrete Element Method simulations of \(\hbox {TiO}_2\) nanoparticle films subjected to mechanical stress. All model elements and parameters are derived in a self-consistent and physically sound way from all-atom Molecular Dynamics simulations of interacting particles and surfaces. In particular, the nature of atomic-scale friction and dissipation effects is taken into account by explicit modelling of the surface features and water adsorbate layers that strongly mediate the particle-particle interactions. The quantitative accuracy of the coarse-grained model is validated against all-atom simulations of \(\hbox {TiO}_2\) nanoparticle agglomerates under tensile stress. Moreover, its predictive power is demonstrated with calculations of force-displacement curves of entire nanoparticle films probed with force spectroscopy. The simulation results are compared with Atomic Force Microscopy and Transmission Electron Microscopy experiments. 相似文献
15.
We define realizability semantics for Light Affine Logic (
LAL\mathsf{LAL}
) which has the property that denotations of functions are polynomial time computable by construction of the model. This gives
a new proof of polytime-soundness of
LAL\mathsf{LAL}
which is considerably simpler than the standard proof based on proof nets and is entirely semantical in nature. The model
construction uses a new instance of a resource monoid; a general method for interpreting systems based on Linear Logic introduced
earlier by the authors. 相似文献
16.
Paulo Anselmo da Mota Silveira Neto Ivan do Carmo Machado John D. McGregorEduardo Santana de Almeida Silvio Romero de Lemos Meira 《Information and Software Technology》2011,53(5):407-423
Context
In software development, Testing is an important mechanism both to identify defects and assure that completed products work as specified. This is a common practice in single-system development, and continues to hold in Software Product Lines (SPL). Even though extensive research has been done in the SPL Testing field, it is necessary to assess the current state of research and practice, in order to provide practitioners with evidence that enable fostering its further development.Objective
This paper focuses on Testing in SPL and has the following goals: investigate state-of-the-art testing practices, synthesize available evidence, and identify gaps between required techniques and existing approaches, available in the literature.Method
A systematic mapping study was conducted with a set of nine research questions, in which 120 studies, dated from 1993 to 2009, were evaluated.Results
Although several aspects regarding testing have been covered by single-system development approaches, many cannot be directly applied in the SPL context due to specific issues. In addition, particular aspects regarding SPL are not covered by the existing SPL approaches, and when the aspects are covered, the literature just gives brief overviews. This scenario indicates that additional investigation, empirical and practical, should be performed.Conclusion
The results can help to understand the needs in SPL Testing, by identifying points that still require additional investigation, since important aspects regarding particular points of software product lines have not been addressed yet. 相似文献17.
Jesús P. Mena-Chalco Ives Macêdo Luiz Velho Roberto M. Cesar Jr. 《The Visual computer》2009,25(10):899-909
In this paper, we present a 3D face photography system based on a facial expression training dataset, composed of both facial range images (3D geometry) and facial texture (2D photography). The proposed system allows one to obtain a 3D geometry representation of a given face provided as a 2D photography, which undergoes a series of transformations through the texture and geometry spaces estimated. In the training phase of the system, the facial landmarks are obtained by an active shape model (ASM) extracted from the 2D gray-level photography. Principal components analysis (PCA) is then used to represent the face dataset, thus defining an orthonormal basis of texture and another of geometry. In the reconstruction phase, an input is given by a face image to which the ASM is matched. The extracted facial landmarks and the face image are fed to the PCA basis transform, and a 3D version of the 2D input image is built. Experimental tests using a new dataset of 70 facial expressions belonging to ten subjects as training set show rapid reconstructed 3D faces which maintain spatial coherence similar to the human perception, thus corroborating the efficiency and the applicability of the proposed system. 相似文献
18.
The bilateral filter is a nonlinear filter that smoothes a signal while preserving strong edges. It has demonstrated great
effectiveness for a variety of problems in computer vision and computer graphics, and fast versions have been proposed. Unfortunately,
little is known about the accuracy of such accelerations. In this paper, we propose a new signal-processing analysis of the
bilateral filter which complements the recent studies that analyzed it as a PDE or as a robust statistical estimator. The
key to our analysis is to express the filter in a higher-dimensional space where the signal intensity is added to the original
domain dimensions. Importantly, this signal-processing perspective allows us to develop a novel bilateral filtering acceleration
using downsampling in space and intensity. This affords a principled expression of accuracy in terms of bandwidth and sampling.
The bilateral filter can be expressed as linear convolutions in this augmented space followed by two simple nonlinearities.
This allows us to derive criteria for downsampling the key operations and achieving important acceleration of the bilateral
filter. We show that, for the same running time, our method is more accurate than previous acceleration techniques. Typically,
we are able to process a 2 megapixel image using our acceleration technique in less than a second, and have the result be
visually similar to the exact computation that takes several tens of minutes. The acceleration is most effective with large
spatial kernels. Furthermore, this approach extends naturally to color images and cross bilateral filtering. 相似文献
19.
New, simple, proofs of soundness (every representable function lies in a given complexity class) for Elementary Affine Logic, LFPL and Soft Affine Logic are presented. The proofs are obtained by instantiating a semantic framework previously introduced by the authors and based on an innovative modification of realizability. The proof is a notable simplification on the original already semantic proof of soundness for the above mentioned logical systems and programming languages. A new result made possible by the semantic framework is the addition of polymorphism and a modality to LFPL, thus allowing for an internal definition of inductive datatypes. The methodology presented proceeds by assigning both abstract resource bounds in the form of elements from a resource monoid and resource-bounded computations to proofs (respectively, programs). 相似文献
20.
Luiz Marcio Cysneiros Julio Cesar Sampaio do Prado Leite Jaime de Melo Sabat Neto 《Requirements Engineering》2001,6(2):97-115
The development of complex information systems calls for conceptual models that describe aspects beyond entities and activities.
In particular, recent research has pointed out that conceptual models need to model goals, in order to capture the intentions
which underlie complex situations within an organisational context. This paper focuses on one class of goals, namely non-functional
requirements (NFR), which need to be captured and analysed from the very early phases of the software development process.
The paper presents a framework for integrating NFRs into the ER and OO models. This framework has been validated by two case
studies, one of which is very large. The results of the case studies suggest that goal modelling during early phases can lead
to a more productive and complete modelling activity. 相似文献