84 resultados para limit sets
Resumo:
In this paper I examine two particular aspects of sounding science fiction film: first, the ulterior, Othering sounds of the alien, whether it is creature, object, technology or environment; and second, the soundscape that accompanies or underscores the type of space travel that crosses temporal and spatial thresholds. In both instances of sounding science fiction film I suggest that human limits are reached and breached, leading to a deterritorialization of the self and a hearing that touches the future which is a moment of pure becoming. I focus on the womanly sonority of the alien to suggest that patriarchal and heterosexist sound devices can be ultimately corrupted. In the analysis of sounding space travel I suggest that science film can create a series of moments in which one experiences the double sublime. This spectacular rendering of a liquid chaos enables the viewer to experience the logic of sensation beyond bodily integrity. In this paper my over-arching position is one that hears in science fiction film the profound potential of a radical alterity that exists beyond the sonorous limit.
Resumo:
This paper uses finite element upper and lower bound limit analysis to produce chart solutions for three-dimensional (3D) natural slopes for both short- and long-term stability. The presented chart solutions are convenient tools that can be used for preliminary design purposes. The rigorous limit analysis results in this paper were found to bracket the true factor of safety within ±10% or better, which can be used as a benchmark for the solutions from other methods. The depth of the slip surfaces is observed to be generally shallow for most analyzed cases, particularly for the long-term slope stability problem. In addition, it was found that using a two-dimensional (2D) analysis may lead to significant differences in estimating safety factors, which can differ by 2%–60% depending on the slope geometry and soil properties. Therefore, great care and judgement are required when applying 2D analyses to 3D slope problems.
Resumo:
Static detection of polymorphic malware variants plays an important role to improve system security. Control flow has shown to be an effective characteristic that represents polymorphic malware instances. In our research, we propose a similarity search of malware using novel distance metrics of malware signatures. We describe a malware signature by the set of control flow graphs the malware contains. We propose two approaches and use the first to perform pre-filtering. Firstly, we use a distance metric based on the distance between feature vectors. The feature vector is a decomposition of the set of graphs into either fixed size k-sub graphs, or q-gram strings of the high-level source after decompilation. We also propose a more effective but less computationally efficient distance metric based on the minimum matching distance. The minimum matching distance uses the string edit distances between programs' decompiled flow graphs, and the linear sum assignment problem to construct a minimum sum weight matching between two sets of graphs. We implement the distance metrics in a complete malware variant detection system. The evaluation shows that our approach is highly effective in terms of a limited false positive rate and our system detects more malware variants when compared to the detection rates of other algorithms.
Resumo:
Stereo matching tries to find correspondences between locations in a pair of displaced images of the same scene in order to extract the underlying depth information. Pixel correspondence estimation suffers from occlusions, noise or bias. In this work, we introduce a novel approach to represent images by means of interval-valued fuzzy sets to overcome the uncertainty due to the above mentioned problems. Our aim is to take advantage of this representation in the stereo matching algorithm. The image interval-valued fuzzification process that we propose is based on image segmentation in a different way to the common use of segmentation in stereo vision. We introduce interval-valued fuzzy similarities to compare windows whose pixels are represented by intervals. In the experimental analysis we show the goodness of this representation in the stereo matching problem. The new representation together with the new similarity measure that we introduce shows a better overall behavior with respect to other very well-known methods.
Resumo:
In this work we present a new construction method of IVFSs from Fuzzy Sets. We use these IVFSs for image processing. Concretely, in this contribution we introduce a new image magnification algorithm using IVFSs. This algorithm is based on block expansion and it is characterized by its simplicity.
Resumo:
In this work we present a simple magnification algorithm for color images. It uses Interval-Valued Fuzzy Sets in such a way that every pixel has an interval membership constructed from its original intensity and its neighbourhood's one. Based on that interval membership, a block is created for each pixel, so this is a block expansion method.
Resumo:
Many previous approaches to frequent episode discovery only accept simple sequences. Although a recent approach has been able to nd frequent episodes from complex sequences, the discovered sets are neither condensed nor accurate. This paper investigates the discovery of condensed sets of frequent episodes from complex sequences. We adopt a novel anti-monotonic frequency measure based on non-redundant occurrences, and dene a condensed set, nDaCF (the set of non-derivable approximately closed frequent episodes) within a given maximal error bound of support. We then introduce a series of effective pruning strategies, and develop a method, nDaCF-Miner, for discovering nDaCF sets. Experimental results show that, when the error bound is somewhat high, the discovered nDaCF sets are two orders of magnitude smaller than complete sets, and nDaCF-miner is more efficient than previous mining approaches. In addition, the nDaCF sets are more accurate than the sets found by previous approaches.
Resumo:
In view of the demand for energy resources, offshore engineering has drawn the attention of many investigators over the past decade. Recent studies have revealed that seabed landslides can have a sig-nificant influence on the performance of offshore infrastructure, such as pipelines. The vulnerability triggered by seabed landslides can even lead to loss of life. In this context, the importance of offshore slope stability evaluation is obvious. Slope stability is generally assessed by the limit equilibrium method (LEM). However, the accuracy of the method is often questioned due to the underlying assumptions that it makes. This study utilises numerical finite element upper and lower bound limit analysis to produce solutions for very gentle undrained slopes. Using these techniques, the stability can be bracketed from above and below. In this paper, a range of slope geometries and the inhomogeneity of the natural soil have been taken into account. The solu-tions presented are useful tools for preliminary design.