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Linearly bounded Turing machines have been mainly studied as acceptors for context-sensitive languages. We define a natural class of infinite automata representing their observable computational behavior, called linearly bounded graphs. These automata naturally accept the same languages as the linearly bounded machines defining them. We present some of their structural properties as well as alternative characterizations in terms of rewriting systems and context-sensitive transductions. Finally, we compare these graphs to rational graphs, which are another class of automata accepting the context-sensitive languages, and prove that in the bounded-degree case, rational graphs are a strict sub-class of linearly bounded graphs.A preliminary version of this article appeared in MFCS 2005. 相似文献
14.
A multiparameter wearable physiologic monitoring system for space and terrestrial applications. 总被引:4,自引:0,他引:4
Carsten W Mundt Kevin N Montgomery Usen E Udoh Valerie N Barker Guillaume C Thonier Arnaud M Tellier Robert D Ricks Robert B Darling Yvonne D Cagle Nathalie A Cabrol Stephen J Ruoss Judith L Swain John W Hines Gregory T A Kovacs 《IEEE transactions on information technology in biomedicine》2005,9(3):382-391
A novel, unobtrusive and wearable, multiparameter ambulatory physiologic monitoring system for space and terrestrial applications, termed LifeGuard, is presented. The core element is a wearable monitor, the crew physiologic observation device (CPOD), that provides the capability to continuously record two standard electrocardiogram leads, respiration rate via impedance plethysmography, heart rate, hemoglobin oxygen saturation, ambient or body temperature, three axes of acceleration, and blood pressure. These parameters can be digitally recorded with high fidelity over a 9-h period with precise time stamps and user-defined event markers. Data can be continuously streamed to a base station using a built-in Bluetooth RF link or stored in 32 MB of on-board flash memory and downloaded to a personal computer using a serial port. The device is powered by two AAA batteries. The design, laboratory, and field testing of the wearable monitors are described. 相似文献
15.
Machine Learning - Probabilistic logic programming (PLP) combines logic programs and probabilities. Due to its expressiveness and simplicity, it has been considered as a powerful tool for learning... 相似文献
16.
The success of several constraint-based modeling languages such as OPL, ZINC or COMET, appeals for better software engineering
practices, particularly in the testing phase. This paper introduces a testing framework enabling automated test case generation
for constraint programming. We propose a general framework of constraint program development which supposes that a first declarative
and simple constraint model is available from the problem specifications analysis. Then, this model is refined using classical
techniques such as constraint reformulation, surrogate, redundant, implied, global constraint and symmetry-breaking to form
an improved constraint model that must be thoroughly tested before being used to address real-sized problems. We think that
most of the faults are introduced in this refinement step and propose a process which takes the first declarative model as
an oracle for detecting non-conformities and derive practical test purposes from this process. We implemented this approach
in a new tool called CPTEST that was used to automatically detect non-conformities on classical benchmark programs, such as the Golomb rulers, n-queens,
social golfer and the car-sequencing problems. 相似文献
17.
Patrick Heymans Quentin Boucher Andreas Classen Arnaud Bourdoux Laurent Demonceau 《International Journal on Software Tools for Technology Transfer (STTT)》2012,14(5):553-566
Software product line engineering seeks to systematise reuse when developing families of similar software systems so as to minimise development time, cost and defects. To realise variability at the code level, product line methods classically advocate usage of inheritance, components, frameworks, aspects or generative techniques. However, these might require unaffordable paradigm shifts for developers if the software was not thought at the outset as a product line. Furthermore, these techniques can be conflicting with a company’s coding practices or external regulations. These concerns were the motivation for the industry–university collaboration described in this paper in which we developed a minimally intrusive coding technique based on tags. The approach was complemented with traceability from code to feature diagrams which were exploited for automated configuration. It is supported by a toolchain and is now in use in the partner company for the development of flight-grade satellite communication software libraries. 相似文献
18.
J L Willems P Arnaud J H van Bemmel P J Bourdillon R Degani B Denis F M Harms P W Macfarlane G Mazzocca J Meyer 《Computers and biomedical research》1985,18(5):439-457
As a result of an international cooperative project entitled "Common Standards for Quantitative Electrocardiography" (CSE), an ECG reference data base has been established with the aim of standardizing computer-derived ECG measurements. The objective of the project is to reduce the wide variation in wave measurements currently obtained by ECG analysis programs. A library of 250 ECGs with selective ECG abnormalities was established and a comprehensive reviewing scheme was devised for the visual determination of the onsets and offsets of P, QRS, and T. This task was performed by a board of cardiologists on highly amplified, selected complexes from the library. A subset was examined in order to study beat-to-beat and intraobserver variability. By using a modified Delphi approach, individual outlying point estimates were eliminated in four successive rounds. In this way final referee estimates were obtained which proved to be highly reproducible and precise. A reference library has thereby been developed which allows testing of the performance of ECG measurement programs and is a useful instrument in establishing recommendations for more precise measurement rules and definitions. 相似文献
19.
Sara Cavaliere-Jaricot Arnaud Etcheberry Michel Herlem Henri Perez 《Electrochimica acta》2007,52(6):2285-2293
Platinum nanoparticles (n-Pt), over-grafted with 2-thiophenecarbonyl chloride are assembled on gold electrodes, by the Langmuir Blodgett (LB) technique using behenic acid (BHA) as promoting agent. These layers are electrochemically active without any preliminary activation. The [Fe(CN)6]3−/4− redox couple was used as electrochemical probe. This paper reports on the influence of the number of deposited LB layers, and the n-Pt density on the electrochemical response. n-Pt density was modified by the change of the “BHA/n-Pt” ratio. Cyclic voltammograms of “[Fe(CN)6]3−/4−” were observed whatever the coating conditions. As soon as the first layer was deposited the electrochemical response was associated to the n-Pt coverage, its response slightly increased up to a steady state for five or seven layers. As expected, the increase of the Pt density favored the increase of the current density. XPS analysis performed before and after electrochemical cycling showed that 4-mercaptoaniline capped platinum nanoparticles, and their over grafting were chemically and electrochemically stable. Analysis of influence of the number or the n-Pt density of the layers showed that the electrochemically active part of LB electrodes was provided by the last layer plus a part of the underlying one. 相似文献
20.
Blondel Arnaud; Nageotte Roland; Bedouelle Hugues 《Protein engineering, design & selection : PEDS》1996,9(2):231-238
Hybrid MalEGVP is a bifunctional protein in vitro sinceit binds maltose as protein MalE of Escherichia coli and sinceit is dimeric and specifically binds single-stranded DNA asprotein GVP of phage M13. The oxidation rate of a unique cysteineresidue was used to compare the stabilities of GVP in its freeand hybrid forms, under conditions where MalE was either foldedor unfolded by a denaturing agent. The results showed that boththe covalent link and tertiary non-covalent interactions betweenMalE and GVP destabilized GVP in MalEGVP. To test whetherGVP had identical structures in its free and hybrid forms, mutationswere used as local conformational probes. The effects of thesemutations on the capabilities of MalEGVP to dimerizeand to bind single-stranded DNA were assayed in vitro. Theywere compatible with the effects of the same mutations on theglobal activity of free GVP in vivo and with the effects thatcould be predicted from the known data on free GVP, in particularits crystal structure. Thus, one partner of a hybrid proteincan be destabilized by the other partner while maintaining itsstructural and functional characteristics. 相似文献