8 resultados para Automated Guideway Transit (AGT)

em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain


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Objective: To compare pressure–volume (P–V) curves obtained with the Galileo ventilator with those obtained with the CPAP method in patients with ALI or ARDS receiving mechanical ventilation. P–V curves were fitted to a sigmoidal equation with a mean R2 of 0.994 ± 0.003. Lower (LIP) and upper inflection (UIP), and deflation maximum curvature (PMC) points calculated from the fitted variables showed a good correlation between methods with high intraclass correlation coefficients. Bias and limits of agreement for LIP, UIP and PMC obtained with the two methods in the same patient were clinically acceptable.

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Purpose: To evaluate the suitability of an improved version of an automatic segmentation method based on geodesic active regions (GAR) for segmenting cerebral vasculature with aneurysms from 3D X-ray reconstruc-tion angiography (3DRA) and time of °ight magnetic resonance angiography (TOF-MRA) images available in the clinical routine.Methods: Three aspects of the GAR method have been improved: execution time, robustness to variability in imaging protocols and robustness to variability in image spatial resolutions. The improved GAR was retrospectively evaluated on images from patients containing intracranial aneurysms in the area of the Circle of Willis and imaged with two modalities: 3DRA and TOF-MRA. Images were obtained from two clinical centers, each using di®erent imaging equipment. Evaluation included qualitative and quantitative analyses ofthe segmentation results on 20 images from 10 patients. The gold standard was built from 660 cross-sections (33 per image) of vessels and aneurysms, manually measured by interventional neuroradiologists. GAR has also been compared to an interactive segmentation method: iso-intensity surface extraction (ISE). In addition, since patients had been imaged with the two modalities, we performed an inter-modality agreement analysis with respect to both the manual measurements and each of the two segmentation methods. Results: Both GAR and ISE di®ered from the gold standard within acceptable limits compared to the imaging resolution. GAR (ISE, respectively) had an average accuracy of 0.20 (0.24) mm for 3DRA and 0.27 (0.30) mm for TOF-MRA, and had a repeatability of 0.05 (0.20) mm. Compared to ISE, GAR had a lower qualitative error in the vessel region and a lower quantitative error in the aneurysm region. The repeatabilityof GAR was superior to manual measurements and ISE. The inter-modality agreement was similar between GAR and the manual measurements. Conclusions: The improved GAR method outperformed ISE qualitatively as well as quantitatively and is suitable for segmenting 3DRA and TOF-MRA images from clinical routine.

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Morphological descriptors are practical and essential biomarkers for diagnosis andtreatment selection for intracranial aneurysm management according to the current guidelinesin use. Nevertheless, relatively little work has been dedicated to improve the three-dimensionalquanti cation of aneurysmal morphology, automate the analysis, and hence reduce the inherentintra- and inter-observer variability of manual analysis. In this paper we propose a methodologyfor the automated isolation and morphological quanti cation of saccular intracranial aneurysmsbased on a 3D representation of the vascular anatomy.

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We present a study on the development and the evaluation of a fully automated radio-frequency glow discharge system devoted to the deposition of amorphous thin film semiconductors and insulators. The following aspects were carefully addressed in the design of the reactor: (1) cross contamination by dopants and unstable gases, (2) capability of a fully automated operation, (3) precise control of the discharge parameters, particularly the substrate temperature, and (4) high chemical purity. The new reactor, named ARCAM, is a multiplasma-monochamber system consisting of three separated plasma chambers located inside the same isothermal vacuum vessel. Thus, the system benefits from the advantages of multichamber systems but keeps the simplicity and low cost of monochamber systems. The evaluation of the reactor performances showed that the oven-like structure combined with a differential dynamic pumping provides a high chemical purity in the deposition chamber. Moreover, the studies of the effects associated with the plasma recycling of material from the walls and of the thermal decomposition of diborane showed that the multiplasma-monochamber design is efficient for the production of abrupt interfaces in hydrogenated amorphous silicon (a-Si:H) based devices. Also, special attention was paid to the optimization of plasma conditions for the deposition of low density of states a-Si:H. Hence, we also present the results concerning the effects of the geometry, the substrate temperature, the radio frequency power and the silane pressure on the properties of the a-Si:H films. In particular, we found that a low density of states a-Si:H can be deposited at a wide range of substrate temperatures (100°C

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The control of the right application of medical protocols is a key issue in hospital environments. For the automated monitoring of medical protocols, we need a domain-independent language for their representation and a fully, or semi, autonomous system that understands the protocols and supervises their application. In this paper we describe a specification language and a multi-agent system architecture for monitoring medical protocols. We model medical services in hospital environments as specialized domain agents and interpret a medical protocol as a negotiation process between agents. A medical service can be involved in multiple medical protocols, and so specialized domain agents are independent of negotiation processes and autonomous system agents perform monitoring tasks. We present the detailed architecture of the system agents and of an important domain agent, the database broker agent, that is responsible of obtaining relevant information about the clinical history of patients. We also describe how we tackle the problems of privacy, integrity and authentication during the process of exchanging information between agents.

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This paper deals with the structural properties of a-Si:H/a-Si1-xCx: H multilayers deposited by glow-discharge decomposition of SiH4 and SiH4 and CH4 mixtures. The main feature of the rf plasma reactor is an automated substrate holder. The plasma stabilization time and its influence on the multilayer obtained is discussed. A series of a-Si:H/a-Si1-xCx: H multilayers has been deposited and characterized by secondary ion mass spectrometry (SIMS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). No asymmetry between the two types of interface has been observed. The results show that the multilayers present a very good periodicity and low roughness. The difficulty of determining the abruptness of the multilayer at the nanometer scale is discussed.

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Recent standardization efforts in e-learning technology have resulted in a number of specifications, however, the automation process that is considered essential in a learning management system (LMS) is a lessexplored one. As learning technology becomes more widespread and more heterogeneous, there is a growing need to specify processes that cross the boundaries of a single LMS or learning resource repository. This article proposes to obtain a specification orientated to automation that takes on board the heterogeneity of systems and formats and provides a language for specifying complex and generic interactions. Having this goal in mind, a technique based on three steps is suggested. The semantic conformance profiles, the business process management (BPM) diagram, and its translation into the business process execution language (BPEL) seem to be suitable for achieving it.

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Automation or semi-automation of learning scenariospecifications is one of the least exploredsubjects in the e-learning research area. There isa need for a catalogue of learning scenarios and atechnique to facilitate automated retrieval of stored specifications. This requires constructing anontology with this goal and is justified inthis paper. This ontology must mainlysupport a specification technique for learning scenarios. This ontology should also be useful in the creation and validation of new scenarios as well as in the personalization of learning scenarios or their monitoring. Thus, after justifying the need for this ontology, a first approach of a possible knowledge domain is presented. An example of a concrete learning scenario illustrates some relevant concepts supported by this ontology in order to define the scenario in such a way that it could be easy to automate.