Search results for "Mach"
showing 10 items of 3360 documents
Semantic and topological classification of images in magnetically guided capsule endoscopy
2012
International audience; Magnetically-guided capsule endoscopy (MGCE) is a nascent technology with the goal to allow the steering of a capsule endoscope inside a water filled stomach through an external magnetic field. We developed a classification cascade for MGCE images with groups images in semantic and topological categories. Results can be used in a post-procedure review or as a starting point for algorithms classifying pathologies. The first semantic classification step discards over-/under-exposed images as well as images with a large amount of debris. The second topological classification step groups images with respect to their position in the upper gastrointestinal tract (mouth, es…
Colour segmentation based on a light reflection model to locate citrus fruits for robotic harvesting
1993
Abstract Colour segmentation with a vision system is a good procedure to identify and locate fruits in robotic harvesting. Natural illumination conditions present in these environments produce a very variable illumination of the scene, in addition, fruits are usually partially occluded, and complete visual information about them is not available. The colour segmentation used for these purposes must take into account the appearance of highlights and shadows that natural illumination conditions produce. A method based on the Dichromatic Reflection Model for the light reflected from the surface object is reported here. Through the assumption of this model the light rays reflected from points o…
LR(k) Parsing
1990
In this chapter we shall generalize the notion of strong LL(k) parsing presented in Chapter 5 and consider a method for deterministic left parsing that applies to a slightly wider class of context-free grammars than does the strong LL(k) parsing method. This method will be called “canonical LL(k) parsing”. As in strong LL(k) parsing, the acronym “LL(k)” means that the input string is parsed (1) in a single Left-to-right scan, (2) producing a Left parse, and (3) using lookahead of length k.
Ambainis-Freivalds’ Algorithm for Measure-Once Automata
2001
An algorithm given by Ambainis and Freivalds [1] constructs a quantum finite automaton (QFA) with O(log p) states recognizing the language Lp = {ai| i is divisible by p} with probability 1 - Ɛ , for any Ɛ > 0 and arbitrary prime p. In [4] we gave examples showing that the algorithm is applicable also to quantum automata of very limited size. However, the Ambainis-Freivalds algoritm is tailored to constructing a measure-many QFA (defined by Kondacs andWatrous [2]), which cannot be implemented on existing quantum computers. In this paper we modify the algorithm to construct a measure-once QFA of Moore and Crutchfield [3] and give examples of parameters for this automaton. We show for the lang…
Improved Constructions of Quantum Automata
2008
We present a simple construction of quantum automata which achieve an exponential advantage over classical finite automata. Our automata use $\frac{4}{\epsilon} \log 2p + O(1)$ states to recognize a language that requires p states classically. The construction is both substantially simpler and achieves a better constant in the front of logp than the previously known construction of [2]. Similarly to [2], our construction is by a probabilistic argument. We consider the possibility to derandomize it and present some preliminary results in this direction.
Tally languages accepted by alternating multitape finite automata
1997
We consider k-tape 1-way alternating finite automata (k-tape lafa). We say that an alternating automaton accepts a language L\(\subseteq\)(Σ*)k with f(n)-bounded maximal (respectively, minimal) leaf-size if arbitrary (respectively, at least one) accepting tree for any (w1, w2,..., wk) ∈ L has no more than $$f\mathop {(\max }\limits_{1 \leqslant i \leqslant k} \left| {w_i } \right|)$$ leaves. The main results of the paper are the following. If k-tape lafa accepts language L over one-letter alphabet with o(log n)-bounded maximal leaf-size or o(log log n)-bounded minimal leaf-size then the language L is semilinear. Moreover, if a language L is accepted with o(log log(n))-bounded minimal (respe…
Promotion of service industries by means of entry restriction: the case of operators in the slot machine industry
2009
This article examines the effects of government policy on entry restriction for firms within a specific market of the Spanish gambling industry. Spain is an ideal economic region for studying this topic, as it allows for the analysis of quasi-identical populations exposed to different regulatory regimes. In Spain, gaming legislation is determined at the autonomous community level (state level), where differences across states within a single country are of particular interest. This paper analyses the performance of slot machine operators in three autonomous communities, each with different policies with regard to entry restriction. Fifty-eight firms were analysed using multiple regression, …
Technical efficiency and the vertical boundaries of the firm: theory and evidence
2013
This article provides a theoretical and empirical analysis of the relationship between firms’ technical efficiency and the vertical organization of production. Technical inefficiency is explicitly introduced as the source of firms’ heterogeneity in a Bertrand–Nash model of industry competition: the main prediction of the model is that the most efficient firms choose vertical integrated structures and the less-efficient ones choose disintegrated structures. The empirical part of the article rests on a stochastic frontier analysis (SFA) in a sample of about 400 Italian machine tool (MT) builders, and the result supports the prediction of the theoretical model.
The iGEM Competition
2014
The international Genetically Engineered Machine (iGEM) competition is a well-known example of synthetic biology and a workbench for the development of heterodox, multidisciplinary and frontier work made by undergraduate students. We review the origin, organization and structure of the competition; we describe how an iGEM team can be set in place, and briefly summarize some of the main milestones and challenges of a competition that is only one decade old. We discuss the links of the competition with the Registry of Standard Biological Parts and the flagship role of iGEM as a very trench of the synthetic biology revolution.
Incremental Generalized Discriminative Common Vectors for Image Classification.
2015
Subspace-based methods have become popular due to their ability to appropriately represent complex data in such a way that both dimensionality is reduced and discriminativeness is enhanced. Several recent works have concentrated on the discriminative common vector (DCV) method and other closely related algorithms also based on the concept of null space. In this paper, we present a generalized incremental formulation of the DCV methods, which allows the update of a given model by considering the addition of new examples even from unseen classes. Having efficient incremental formulations of well-behaved batch algorithms allows us to conveniently adapt previously trained classifiers without th…