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91.
Gilhuly TJ Hutchings SR Dumont GA Macleod BA 《Computer methods and programs in biomedicine》2008,89(2):179-188
The neuromuscular blocker advisory system (NMBAS) is a computer program developed to provide advisory guidance to anesthesiologists on the timing and dose of rocuronium to paralyze patients during surgery. It is believed that the use of such a system will administer the minimally effective amount of drug, maintaining the patient in a state of paralysis that is useful for surgery yet easily reversible. This will improve patient safety and result in more efficient care. In this paper we present the NMBAS, its basic methodology, and its development though a pilot study. Novel methods of handling neuromuscular response data are presented, including relaxation measurement and the enhanced-train-of-four sensing modality. New methods of handling nonlinearities at the neuromuscular junction to allow application of adaptive control techniques are presented. A novel form of modelling combining model swapping and RLSE adaptation to accommodate the patient variation seen with NMB drugs is introduced. A pilot study testing the NMBAS was undergone to prepare the NMBAS for application in a full clinical trial, in which patients undergoing prostate brachytherapy surgeries using rocuronium for intubation were admitted. 相似文献
92.
Aye Akbalk Sekoun Kebe Bernard Penz Najiba Sbihi 《International Transactions in Operational Research》2008,15(2):195-214
In this paper we study the coordination of different activities in a supply chain issued from a real case. Multiple suppliers send raw materials (RMs) to a distribution center (DC) that delivers them to a unique plant where the storage of the RMs and the finished goods is not possible. Then, the finished goods are directly shipped to multiple customers having just‐in‐time (JIT) demands. Under these hypotheses, we show that the problem can be reduced to multiple suppliers and one DC. Afterwards, we analyze two cases; in the first, we consider an uncapacitated storage at DC, and in the second, we analyze the capacitated storage case. For the first case, we show that the problem is NP‐hard in the ordinary sense using the Knapsack decision problem. We then propose two exact methods: a mixed integer linear program (MILP) and a pseudopolynomial dynamic program. A classical dynamic program and an improved one using the idea of Shaw and Wagelmans are given. With numerical tests we show that the dynamic program gives the optimal solution in reasonable time for quite large instances compared with the MILP. For the second case, the capacity limitation in DC is assumed, which makes the problem solving more challenging. We propose an MILP and a dynamic programming‐based heuristic that provides solutions close to the optimal solution in very short times. 相似文献
93.
In the ternary system Ti-Si-C, the ternary compound Ti3SiC2 seems to exhibit promising thermal and mechanical properties. Its synthesis as a thin film from the vapour phase is very difficult owing to the complexity of the system. A contribution to the knowledge of the CVD of Ti3SiC2 from a TiCl4-SiCl4-CH4-H2 gas mixture is proposed on the basis of a thermodynamic approach. This approach is based on a reliable estimation of Ti3SiC2 thermodynamic data in good accordance with recent experimental results on its thermal stability. A first equilibrium calculation for the deposition on an inert substrate shows the influence of the experimental parameters on the composition of both the deposit and the gas phase. As a result, the deposition of Ti3SiC2 can be favoured by an excess of TiCl4 ( 45%), a rather low pressure (10–20 kPa), high temperature ( 1273 K) and low H2 dilution ratio. On the basis of equilibrium calculations for various reactive substrates, complex mechanisms of Ti3SiC2 deposition are pointed out, with intermediate steps of substrate consumption, e.g. the formation of TiC from a carbon substrate or TiSi2 from a silicon substrate. 相似文献
94.
Chapellier Paul Lavenus Pierre Le Traon Olivier Dulmet Bernard 《Microsystem Technologies》2022,28(6):1485-1496
Microsystem Technologies - This paper presents recent advances on two dimensional length-extension mode (2D-LEM) quartz resonators providing high quality (Q) factor on resonances at a few MHz. The... 相似文献
95.
Hassen Ait Atmane Abdelouahed Tounsi Fabrice Bernard 《International Journal of Mechanics and Materials in Design》2017,13(1):71-84
The novelty of this paper is the use of an efficient beam theory for bending, free vibration and buckling analysis of functionally graded material (FGM) beams on two-parameter elastic foundation. The present theory accounts for both shear deformation and thickness stretching effects by a parabolic variation of all displacements across the thickness, and satisfies the stress-free boundary conditions on the upper and lower surfaces of the beam without requiring any shear correction factor. Due to porosities, possibly occurring inside FGMs during fabrication, it is therefore necessary to consider the vibration, bending and buckling behaviors of beams having porosities in this work. The equation of motion for FGM beams is obtained through Hamilton’s principle. The closed form solutions are obtained by using Navier technique, and then fundamental frequencies are found by solving the results of eigenvalue problems. The validity of the present theory is investigated by comparing some of the present in literature. It can be concluded that the proposed theory is accurate and simple in solving the bending, free vibration and buckling behaviors of FGM sandwich beams. 相似文献
96.
Michelle Elias Erika Nnang‐Obada Bernard Charpentier Antoine Durrbach Severine Beaudreuil 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(1):45-49
Introduction: Adequate hemodialysis directly improves health. Puncturing an arteriovenous fistula (AVF) and the amount of blood recirculation greatly affect the quality of dialysis. Few studies have assessed the method to cannulate a fistula and its influence on efficiency of hemodialysis. Methods: This prospective pilot study included 14 patients with end‐stage renal failure receiving regular intermittent hemodialysis. Patients received three consecutive treatments with both needles directed upstream then three consecutive treatments with the venous needle directed upstream and the arterial needle directed downstream. With both techniques, the distance between the needles was kept constant at 2.5 cm. Recirculation rate and Kt/V ratio were measured during each treatment using thermodilution and a diascan Fresenius generator. Findings: The 14 patients received 84 hemodialysis sessions: i.e., 8 (57.1%) males and 6 (42.8%) females, mean age 62.3 ± 15.57 years. Results showed that mean recirculation rates and Kt/V did not significantly differ between the two techniques. Discussion: Because no significant difference was found between the two techniques, the direction of insertion of needles should be decided upon on a case‐by‐case basis depending on the anatomy of the AVF and the feasibility of the puncture. 相似文献
97.
Forked laser eigenstates are shown to provide a powerful tool both to phase lock spatially separated laser oscillators and to add their powers coherently into a TEM(00) output beam. Coherent addition of the powers extracted from two fiber-coupled diode-pumped Nd:YAG channels is theoretically and experimentally demonstrated. Pure TEM(00) oscillation is obtained with a 20% optical-to-optical conversion efficiency. The coherence of the two-propagation-axis laser is proved, and single-frequency operation is demonstrated. The scalability of the scheme is discussed. 相似文献
98.
Aurélien Bellet Author Vitae Marc Bernard Author Vitae Thierry Murgue Author Vitae Marc Sebban Author Vitae 《Pattern recognition》2010,43(6):2330-2339
During the past few years, several works have been done to derive string kernels from probability distributions. For instance, the Fisher kernel uses a generative model M (e.g. a hidden Markov model) and compares two strings according to how they are generated by M. On the other hand, the marginalized kernels allow the computation of the joint similarity between two instances by summing conditional probabilities. In this paper, we adapt this approach to edit distance-based conditional distributions and we present a way to learn a new string edit kernel. We show that the practical computation of such a kernel between two strings x and x′ built from an alphabet Σ requires (i) to learn edit probabilities in the form of the parameters of a stochastic state machine and (ii) to calculate an infinite sum over Σ* by resorting to the intersection of probabilistic automata as done for rational kernels. We show on a handwritten character recognition task that our new kernel outperforms not only the state of the art string kernels and string edit kernels but also the standard edit distance used by a neighborhood-based classifier. 相似文献
99.
Abstract: Enterprise production is becoming more and more knowledge oriented nowadays and knowledge management is playing a key role in making commercial profit and maintaining enterprise competence. Knowledge characterization and measurement are the bases of knowledge management, and this paper aims to develop a method for characterizing and measuring knowledge in a comprehensive and practical way. Knowledge in its static state is modelled as a vector, whose values vary with the situation, and changes in state are modelled as a finite state machine. 相似文献
100.
Understanding argumentation and its role in human reasoning has been a continuous subject of investigation for scholars from
the ancient Greek philosophers to current researchers in philosophy, logic and artificial intelligence. In recent years, argumentation
models have been used in different areas such as knowledge representation, explanation, proof elaboration, commonsense reasoning,
logic programming, legal reasoning, decision making, and negotiation. However, these models address quite specific needs and
there is need for a conceptual framework that would organize and compare existing argumentation-based models and methods.
Such a framework would be very useful especially for researchers and practitioners who want to select appropriate argumentation
models or techniques to be incorporated in new software systems with argumentation capabilities. In this paper, we propose
such a conceptual framework, based on taxonomy of the most important argumentation models, approaches and systems found in
the literature. This framework highlights the similarities and differences between these argumentation models. As an illustration
of the practical use of this framework, we present a case study which shows how we used this framework to select and enrich
an argumentation model in a knowledge acquisition project which aimed at representing argumentative knowledge contained in
texts critiquing military courses of action. 相似文献