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801.
Roberto Gerson A. Azevedo Eduardo Cruz Araújo Bruno Lima Luiz Fernando G. Soares Marcelo F. Moreno 《Multimedia Tools and Applications》2014,70(2):1199-1228
This paper discusses the importance of non-functional requirements in the design of hypermedia authoring tools, which typically provides multiple graphical abstractions (views). It focuses on creating products and services that operate robustly across a broad range of environments, and that take into account the changeable needs of their users over time, as they become more familiar with the tool. In order to meet these non-functional aspects, this paper proposes a microkernel-based architecture for authoring tools, where the microkernel is responsible for instantiating the requested extensions (plugins), maintaining the core data model that represents the hypermedia document under development, and notifying changes in this model to plugins interested in them. Based on the proposed architecture, a new version of Composer (an NCL authoring tool) is presented, rewritten from scratch. Results from experiments show that the discussed non-functional requirements are adequately met. 相似文献
802.
K. Ravichandran N. Jabena Begum S. Snega B. Sakthivel 《Materials and Manufacturing Processes》2016,31(11):1411-1423
Owing to the low-cost, nontoxicity and abundance, aluminum-doped zinc oxide (AZO) thin films become a better alternative to indium tin oxide (ITO) films. Therefore, development of AZO films with transparent conducting properties comparable to that of ITO is one of the main focuses of material scientists, and hence various ways and means are attempted for the past two decades. Also, the production of cost-effective transparent conducting oxide (TCO) films is a presently engaged task of R&D departments of optoelectronic industries. In this paper, we present a detailed review on the effects of various process parameters on the characteristics of AZO thin films deposited using one of the low-cost fabrication techniques called spray pyrolysis. More than 100 original research articles related to this topic have been surveyed and analyzed critically. Results obtained from our experimental work are compared with the collected data, and an interesting correlation between the properties of AZO films has been found out and reported. 相似文献
803.
We present a closed-loop technique for measuring wavelength shifts associated with fiber Bragg gratings by using a fused biconical wavelength division multiplexer (WDM). The spectral response of the WDM is actively tuned by stretching of the coupling region to maintain a fixed coupling ratio at the reflected Bragg wavelength. The closed-loop operation allows sensitivities usually associated with a highly selective WDM to be obtained without compromising the measurement range. A simple theoretical model is presented together with experimental results for temperature and strain measurements. 相似文献
804.
MulRoGA: A Multicast Routing Genetic Algorithm approach considering multiple objectives 总被引:1,自引:1,他引:0
We solve a multicast routing problem by means of a genetic algorithm (GA) without using multicast trees. The source-destination
routes need to fulfill two conflicting objectives: maximization of the common links and minimization of the route sizes. The
proposed GA can be characterized by its representation of network links and routes in a variable size multi-chromosome problem;
local viability restrictions in order to generate the initial population and define variation operators; selection operators
in order to choose the most promising individuals thus preserving diversity, and the fitness function in order to handle the
conflicting multiple objectives. The proposed model is called a Multicast Routing Genetic Algorithm (MulRoGA). The model was
tested on the 33-node European GéANT WAN network backbone and three other networks (66-node, 100-node and 200-node) randomly
generated using the Waxman model on a network topology generator BRITE. On considering each network, a number of solutions
were found for changes in the size and node members of the multicast groups, and the source node. The results of the MulRoGA
operation suggest a consistent and robust performance in the various cases including comparisons with the methods of unicast
shortest path routing, shortest path tree routing (SPT), and simulated annealing (SA) heuristic. 相似文献
805.
Ricardo Jota Bruno R. de Araújo Luís C. Bruno João M. Pereira Joaquim A. Jorge 《Journal of Real-Time Image Processing》2010,5(2):91-107
IMMIView is an interactive system that relies on multiple modalities and multi-user interaction to support collaborative design
review. It was designed to offer natural interaction in visualization setups such as large-scale displays, head mounted displays
or TabletPC computers. To support architectural design, our system provides content creation and manipulation, 3D scene navigation
and annotations. Users can interact with the system using laser pointers, speech commands, body gestures and mobile devices.
In this paper, we describe how we design a system to answer architectural user requirements. In particular, our system takes
advantage of multiple modalities to provide a natural interaction for design review. We also propose a new graphical user
interface adapted to architectural user tasks, such as navigation or annotations. The interface relies on a novel stroke-based
interaction supported by simple laser pointers as input devices for large-scale displays. Furthermore, input devices such
as speech and body tracking allow IMMIView to support multiple users. Moreover, they allow each user to select different modalities
according to their preference and modality adequacy for the user task. We present a multi-modal fusion system developed to
support multi-modal commands on a collaborative, co-located, environment, i.e. with two or more users interacting at the same
time, on the same system. The multi-modal fusion system listens to inputs from all the IMMIView modules in order to model
user actions and issue commands. The multiple modalities are fused based on a simple rule-based sub-module developed in IMMIView
and presented in this paper. User evaluation performed over IMMIView is presented. The results show that users feel comfortable
with the system and suggest that users prefer the multi-modal approach to more conventional interactions, such as mouse and
menus, for the architectural tasks presented. 相似文献
806.
A CASE-BASED DECISION SUPPORT SYSTEM FOR INDIVIDUAL STRESS DIAGNOSIS USING FUZZY SIMILARITY MATCHING
Shahina Begum Mobyen Uddin Ahmed Peter Funk Ning Xiong Bo Von Schéele 《Computational Intelligence》2009,25(3):180-195
Stress diagnosis based on finger temperature (FT) signals is receiving increasing interest in the psycho-physiological domain. However, in practice, it is difficult and tedious for a clinician and particularly less experienced clinicians to understand, interpret, and analyze complex, lengthy sequential measurements to make a diagnosis and treatment plan. The paper presents a case-based decision support system to assist clinicians in performing such tasks. Case-based reasoning (CBR) is applied as the main methodology to facilitate experience reuse and decision explanation by retrieving previous similar temperature profiles. Further fuzzy techniques are also employed and incorporated into the CBR system to handle vagueness, uncertainty inherently existing in clinicians reasoning as well as imprecision of feature values. Thirty-nine time series from 24 patients have been used to evaluate the approach (matching algorithms) and an expert has ranked and estimated similarity. On average goodness-of-fit for the fuzzy matching algorithm is 90% in ranking and 81% in similarity estimation that shows a level of performance close to an experienced expert. Therefore, we have suggested that a fuzzy matching algorithm in combination with CBR is a valuable approach in domains, where the fuzzy matching model similarity and case preference is consistent with the views of domain expert. This combination is also valuable, where domain experts are aware that the crisp values they use have a possibility distribution that can be estimated by the expert and is used when experienced experts reason about similarity. This is the case in the psycho-physiological domain and experienced experts can estimate this distribution of feature values and use them in their reasoning and explanation process. 相似文献
807.
Laerte G. Ferreira Edson E. Sano Luis E. Fernandez Fernando M. Araújo 《International journal of remote sensing》2013,34(1):154-167
Cultivated pastures are the dominant land-use unit in Brazil, with the cattle raising sector representing ~50% of the total Brazilian emissions of greenhouse gases. About 44% of the Brazilian cattle herd is located in the 204 million ha Cerrado, the Brazilian savanna biome and one of the world's hotspots for conservation, where pasture is still the major driving force behind the ongoing land clearance. In the face of the environmental challenges posed by the Cerrado cultivated pastures, 50% of which are estimated to be already severely degraded and where most of the pasture-related fires in Brazil occur, in this study we report the findings on the use of key Moderate Resolution Imaging Spectroradiometer (MODIS) Land (MODLAND) products for retrieving biophysical patterns and trends of cultivated pastures over the entire Brazilian savanna biome. The areas of Cerrado covered by cultivated pastures were analysed by the following 2008 MODIS products: MOD13Q1 enhanced vegetation index, MOD11A2 land-surface temperature, MOD15A2 leaf area index, and MCD45A1 fire-affected areas. Specifically, 23 MOD13Q1 composites for the whole year of 2008 were used as a net primary productivity proxy. Our results indicate the ability of moderate resolution orbital imagery to consistently depict the main characteristics and regional variation in the biophysical properties of the Cerrado pastures, which clearly depend on management practices, usage, and environmental conditions. In particular, these results corroborate the feasibility of an operational MODIS-based monitoring system providing early fire warnings and overall quality assessments in support of a more efficient and sustainable herd occupation and more appropriate land-use destination. 相似文献
808.
This paper proposes an information-theoretic approach for clustering with a new measure of cross information potential and two clustering algorithms. Instead of using all points of the dataset, the proposed measure uses representative points to quantify the interaction between distributions without any loss of the original properties of cross information potential. This brings a double advantage. It decreases the cost of computing the cross information potential, thus drastically reducing the running time. Secondly, it captures the interaction among the data points by utilizing the underlying statistics of the space region centered around the representative points. With this, we have made it possible to use cross information potential in applications where it was not. We also proposed two algorithms for clustering which explore the idea of creating links between regions of the feature space that are highly correlated. We ran several tests and compared the results with single linkage hierarchical algorithm, finite mixture of Gaussians and spectral clustering in both synthetic and real image segmentation datasets. Experiments showed that our approach achieved better results compared to the other algorithms and it was capable of capture the real structure of the data in most cases regardless of its complexity. It also produced good image segmentation with the advantage of a tuning parameter that provides a way of refine segmentation. 相似文献
809.
Gustavo Callou Paulo Maciel Dietmar Tutsch João Ferreira Julian Araújo Rafael Souza 《Computing》2013,95(12):1137-1170
The advent of services such as cloud computing, social networks and e-commerce has led to an increased demand for computer resources from data centers. Prominent issues for data center designers are sustainability, cost, and dependability, which are each significantly affected by the redundant architectures required to support these services. Within this context, models are important tools for designers when attempting to quantify these issues before implementing the final architecture. This paper proposes a set of models for the integrated quantification of the sustainability impact, cost, and dependability of data center power and cooling infrastructures. This is achieved with the support of an environment called ASTRO. The approach taken to perform the system dependability evaluation employs a hybrid modeling strategy which recognizes the advantages of both stochastic Petri nets and reliability block diagrams. Additionally, an energy flow model is proposed to estimate the environmental impact and cost of data center architectures whilst respecting the energy constraints of each device. This work also presents a case study which analyzes the environmental impact and dependability metrics as well as the operational energy cost of real-world data center power and cooling architectures within the context of the energy mixes of the US and Brazil. 相似文献
810.
For a long time, it was believed there was no reason to include the geometrical phase in studying the propagation of gaussian optical beams through dielectric blocks. This can be justified by the fact that the first-order term in the Taylor expansion of this phase is responsible for the lateral shift of the optical beam which is also predicted by ray optics. From this point of view, the geometrical phase can be seen as a purely auxiliary concept. In this paper, we show how the second-order term in the Taylor expansion accounts for the symmetry breaking of the transversal spatial distribution and acts as an axial spreading modifier. These new effects clearly show the importance of the geometrical phase in describing the correct behavior of light. To test our theoretical predictions, we briefly discuss a possible experimental implementation. 相似文献