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Jitka Kühnová and Lenka Přibylová

References [1] AUGER, P.-PARRA, R. B-MORAND, S.-SÁNCHEZ, E.: A predator-prey model with predators using hawk and dove tactics, Mathematical Biosciences 177&178 (2002), 185-200. [2] KUZNETSOV, Y. A.: Elements of Applied Bifurcation Theory. Springer-Verlag, Berlin, New York, Inc. 1998.

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Jevgeņijs Stepanovs, Agnese Ozoliņa, Vita Rovīte, Biruta Mamaja and Indulis Vanags

Abstract

Microvascular free flap surgery, has become an important part of reconstructive surgery during the last decades, as it allows closure of various tissue defects and recovery of organs function. Despite surgical progress resulting in high rates of transferred tissue survival, the risk of pedicle vessels thrombosis still remains a significant problem. A total of 108 articles from Pubmed and Science Direct databases published in 2005–2015 were analysed. This review of the literature assessed the influence of patient-dependent risk factors and different perioperative management strategies on development of microvascular free flap thrombosis. Sufficient evidence for risk associated with hypercoagulation, advanced age and certain comorbidities was identified. Presently, rotational thromboelastometry allows early hypercoagulability detection, significantly changing further patient management. Identification of flap thrombosis promoting surgery-related aspects is also essential in preoperative settings. Choice of anaesthesia and postoperative analgesia, administration of different types and amounts of fluids, blood products and vasoactive agents, temperature control are no less important in perioperative anaesthesiological management. More attention should be focused on timely preoperative evaluation of patient-dependent risk factors, which can influence anaesthesiological and surgical tactics during and after microvascular free flap surgery. Perioperative anaesthesiological management strategy continues to be controversial and therefore it should be performed based on thrombotic risk assessment and patient individual needs, thus improving flap survival rates and surgical outcome.

Open access

Yun Gao, Mohammad Reza Farahani and Wei Gao

Abstract

In this article, we propose an ontology learning algorithm for ontology similarity measure and ontology mapping in view of distance function learning techniques. Using the distance computation formulation, all the pairs of ontology vertices are mapped into real numbers which express the distance of their corresponding vectors. The more distance between two vertices, the smaller similarity between their corresponding concepts. The stabilities of our learning algorithm are defined and several bounds are yielded via stability assumptions. The simulation experimental conclusions show that the new proposed ontology algorithm has high efficiency and accuracy in ontology similarity measure and ontology mapping in certain engineering applications.

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Linli Zhu, Yu Pan and Jiangtao Wang

an ontology optimization tactics according to distance calculating techniques. More theoretical analysis of ontology learning algorithm can be referred to Gao et al. [ 16 ]. In this paper, we propose a new ontology learning trick based on affine transformation. Furthermore, we present the efficiency of the algorithm in the biology and chemical applications via experiments. 2 Setting Let V be an instance space. We use p dimension vector to express the semantics information of each vertex in ontology graph. Specifically, let v = { v 1 , ···, v p } be