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121.
Maria A. Lambrou Kay Endre Fjrtoft Efstathios D. Sykas Nikitas Nikitakos 《Telematics and Informatics》2008,25(2):72-83
The Intelligent Maritime Environment (i-MARE) framework and technological platform we introduce in our paper conceptualize an innovative, collaborative and context-aware network business model for cargo shipping. The i-MARE framework considers ambient-intelligence technologies, in particular an ontology-derived and web semantics based interoperability framework and application modules for key shipping process areas, namely the maritime regulations-rules compliance and port operations support. We explain how the improvement of the later operations can be realized in terms of the proposed technological platform towards the effective matching of individual companies’ capabilities and needs with market demands for cargo shipping. Whereas cargo shipping refers to a number of different markets, our framework is generic and adaptable to the requirements of particular sectors, for instance ocean bulk shipping or short sea container shipping. The framework presented is proposed for testing and application in the maritime sector, whereas in our paper we examine, as a proof of concept, short sea shipping business cases and a normative modelling and architectural solution. 相似文献
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OBJECTIVES: To test the rapidity of a continuous PCO2 measurement system response to brief reductions in gut perfusion from transient episodes of graded aortic hypotension, and to investigate the relationship between the increase in ileal luminal PCO2 and mean aortic pressure during the episodes. DESIGN: Prospective, experimental animal study. SETTING: University research laboratory. SUBJECTS: Adult male Sprague-Dawley rats, weighing 430 to 510 g. INTERVENTIONS: Five Sprague-Dawley rats were anesthetized with intraperitoneal sodium phenobarbital and ventilated with 100% oxygen via tracheostomy to a PaCO2 of 30 to 50 torr (4.0 to 6.7 kPa). Distal aortic pressure was monitored invasively, and a sensor was inserted into the ileal lumen. Luminal PCO2 measurements were recorded every 2 secs. Normal saline was infused at 3 mL/hr, and isoflurane was titrated to a mean aortic pressure of 80 to 100 mm Hg. In each rat, paired 2-min inductions of distal aortic hypotension were induced by digital elevation of an aortic silk sling above the celiac artery to as many as possible of the following pressures (mm Hg): 60, 50, 40, 30, 20, and 10. The experiment was stopped if instability of luminal PCO2 or hypotension persisted through the intervening 8-min recovery periods. MEASUREMENTS AND MAIN RESULTS: One rat completed paired inductions of all six goal aortic pressures. Two rats completed five inductions. One rat completed four inductions, and one rat completed three inductions. The times to onset of luminal hypercapnia and to peak luminal hypercapnia were highly consistent and independent of the degree of hypotension. Onset of hypercapnia was usually detected < 1 min after aortic elevation, but peak luminal hypercapnia occurred approximately 1 min after release of the aortic sling. Regression analysis showed an inverse linear relationship between the maximum increase in luminal PCO2 above baseline and mean aortic pressure during induced hypotension (r2 = .6; p < .001). CONCLUSIONS: Continuous ileal luminal PCO2 measurement by the sensor is rapidly responsive to brief reductions in aortic pressure in a rat model. Maximum luminal PCO2 increase during such perturbations is inversely related to mean aortic pressure. 相似文献
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Wolfgang Maass Georg Schnitger Endre Szemerédi György Turán 《Computational Complexity》1993,3(4):392-401
We prove the first superlinear lower bound for a concrete, polynomial time recognizable decision problem on a Turing machine with one work tape and a two-way input tape (also called off-line 1-tape Turing machine).In particular, for off-line Turing machines we show that two tapes are better than one and that three pushdown stores are better than two (both in the deterministic and in the nondeterministic case). 相似文献
126.
Krishanu Chatterjee Asaithambi Suresh Saibal Ganguly Kajari Kargupta Dipali Banerjee 《Materials Characterization》2009,60(12):1597-1601
The present work consists of synthesis and characterization of a novel thermoelectric material polyaniline (PANI)-bismuth telluride (Bi2Te3) nanocomposite using simultaneous electrochemical reactions and deposition method. The inorganic bismuth nitrate has been used as a dopant for polyaniline to achieve high electrical conductivity. A semi-batch mode of operation has been employed to control the rate of deposition of an individual component and thus the molecular architecture of the composite. The electro-deposited composite film on ITO coated glass substrate has been characterized by X-ray diffraction analysis (XRD), FTIR analysis, scanning electron microscope (SEM), and transmission electron microscope (TEM). The microscopic analysis reveals the formation of rod-like nanostructures of diameter less than 100 nm. It has been found that smaller molecules of Bi2Te3 are dispersed in the macromolecules of PANI. The nanocomposite has been characterized by thermoelectric power. 相似文献