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1812. A novel algorithm for the modeling of complex processes
- Creator:
- Rubio, José de Jesús, Lughofer, Edwin, Angelov, Plamen, Novoa, Juan Francisco, and Meda-Campaña, Jesús A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- recursive least square, Kalman filter, modeling, and complex processes
- Language:
- English
- Description:
- In this investigation, a new algorithm is developed for the updating of a neural network. It is concentrated in a fuzzy transition between the recursive least square and extended Kalman filter algorithms with the purpose to get a bounded gain such that a satisfactory modeling could be maintained. The advised algorithm has the advantage compared with the mentioned methods that it eludes the excessive increasing or decreasing of its gain. The gain of the recommended algorithm is uniformly stable and its convergence is found. The new algorithm is employed for the modeling of two synthetic examples.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1813. A novel approach to modelling of flow in fractured porous medium
- Creator:
- Šembera, Jan, Maryška, Jiří, Královcová, Jiřina, and Severýn, Otto
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- finite element method, Darcy´s flow, and fractured porous medium
- Language:
- English
- Description:
- There are many problems of groundwater flow in a disrupted rock massifs that should be modelled using numerical models. It can be done via "standard approaches'' such as increase of the permeability of the porous medium to account the fracture system (or double-porosity models), or discrete stochastic fracture network models. Both of these approaches appear to have their constraints and limitations, which make them unsuitable for the large-scale long-time hydrogeological calculations. In the article, a new approach to the modelling of groudwater flow in fractured porous medium, which combines the above-mentioned models, is described. This article presents the mathematical formulation and demonstration of numerical results obtained by this new approach. The approach considers three substantial types of objects within a structure of modelled massif important for the groudwater flow - small stochastic fractures, large deterministic fractures, and lines of intersection of the large fractures. The systems of stochastic fractures are represented by blocks of porous medium with suitably set hydraulic conductivity. The large fractures are represented as polygons placed in 3D space and their intersections are represented by lines. Thus flow in 3D porous medium, flow in 2D and 1D fracture systems, and communication among these three systems are modelled together.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1814. A novel association between Aphaenogaster subterranea (Hymenoptera: Formicidae) and the nymphs of Reptalus panzeri (Hemiptera: Cixiidae)
- Creator:
- Lörinczi, Gábor
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Formicidae, Aphaenogaster subterranea, Hemiptera, Cixiidae, Reptaluls panzeri, ant-hemipteran, association, insect-insect relationship, myrmecophily, Fraxinus ornus, ash, 2, and 59
- Language:
- English
- Description:
- Gábor Lörinczi.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1815. A Novel attribute-based access control model for multimedia social networks
- Creator:
- Zhang, Z., Han, L., Li, C., and Wang, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- multimedia social networks, attribute-based acces control, security, and prototype
- Language:
- English
- Description:
- Multimedia social networks (MSNs) provide great convenience to users, while privacy leaks issues are becoming prominent. The studies on relationship-based access control have been widely used in social networks. However, with the dynamic development of social networks and rapid growth of user information, the access control does not completely meet the current system's need. In this paper, an attribute-based access control model called ABAC{MSN is proposed for MSNs. This model comprehensively considers user attributes, environment attributes and resource attributes, not only including relationships among users. In this model, users can set multimedia usage control policies based on three categories of user-defined attributes. A formal theoretical model is established, which includes constraint rules, data ow rules, policy conflict resolution mechanism, and applied to CyVOD.net, a multimedia social-network-platform prototype systems. The deployment and application denote that this method effectively and exibly addresses use-case scenarios of multi-attribute-based media access control, and improves the access security of social media platforms and resources.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1816. A novel carboxymethylated mercaptotriazinoindole inhibitor of aldose reductase interferes with the polyol pathway in streptozotocin-induced diabetic rats
- Creator:
- Soltesova Prnova, M., Ballekova, J., Alena Gajdošíková, Gajodsik, A., and Stefek, M.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, diabetici, diabetics, carboxymethylated mercaptotriazinoindole, aldose reductase inhibitor, polyol pathway, diabetic complications, 14, and 612
- Language:
- English
- Description:
- The aim of the present work was to study the effect of 3- mercapto-5H-1,2,4-triazino[5,6-b]indole-5-acetic acid (CMTI), an efficient aldose reductase inhibitor, on sorbitol accumulation in selected organs of streptozotocin-induced diabetic rats in vivo . In addition, the effect of CMTI on aldose reductase back reaction and on sorbitol dehydrogenase was determined. The model of experimental diabetes in male Wistar rats induced by streptozotocin was used. Experimental diabetes was induced by triple intraperitoneal doses of streptozotocin on three consecutive days. In diabetic rats, significant elevation of sorbitol concentration in the sciatic nerve and eye lenses was recorded. CMTI administered intragastrically (50 mg/kg/day) for five consecutive days significantly inhibited sorbitol accumulation in the sciatic nerve, yet it was without effect in eye lenses of diabetic animals. For aldose reductase back reaction, the substrate affinity of glycerol to aldose reductase was one order lower than that of glyceraldehyde in forward reaction. In addition, the back reaction was much slower, characterized by Vmax value of about 30 times lower than that of the forward reaction. Inhibition of aldose reductase by CMTI was characterized by closely related IC50 values in submicromolar range for both forward and back reactions. No significant inhibition of the second enzyme of the polyol pathway, sorbitol dehydrogenase, by 100 μM CMTI was recorded (I=0.9±2.7 %, n=3). To conclude, the presented results showed the ability of CMTI to affect the polyol pathway in diabetic rats in vivo and represent thus a further step in a complex preclinical evaluation of CMTI as a potential agent for treatment of chronic diabetic complications., M. Soltesova Prnova, J. Ballekova, A. Gajdosikova, A. Gajdosik, M. Stefek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1817. A novel construction and mechanical principles of five-fingered prosthetic hand
- Creator:
- Žajdlík, Jakub
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- prosthetic, grasp, EMG, hand, and biomechanics
- Language:
- English
- Description:
- This paper presents idea flow, development and construction of an anthropomorphic hand which is intended to be used mainly in prosthetics. Fundamental results of simulations and optimization of grasp are shown. The prototype has been manufactured and the principal functionality of finger mechanism (drive three axes by one string) has been tested. A new mechanical principle has been developed which is based again on an idea of using less actuators then joints with keeping adaptability and functionality of the mechanism. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1818. A novel endosymbiont-containing trypanosomatid Phytomonas borealis sp. n. from the predatory bug Picromerus bidens (Heteroptera: Pentatomidae)
- Creator:
- Ganyukova, Anna I, Frolov, Alexander O, Malysheva, Marina N, Spodareva, Viktoria V, Vyacheslav Yurchenko, and Kostygov, Alexei Yu
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- dravé ryby, predatory fishes, new trypanosomatid species, prokaryotic endosymbionts, non-specific infection, 2, and 59
- Language:
- English
- Description:
- Here we describe the new trypanosomatid, Phytomonas borealis sp. n., from the midgut of the spiked shieldbugs, Picromerus bidens (Linnaeus), collected in two locations, Novgorod and Pskov Oblasts of Russia. The phylogenetic analyses, based on the 18S rRNA gene, demonstrated that this flagellate is a sister species to the secondary monoxenous Phytomonas nordicus Frolov et Malysheva, 1993, which was concurrently documented in the same host species in Pskov Oblast. Unlike P. nordicus, which can complete its development (including exit to haemolymph and penetration into salivary glands) in Picromerus bidens, the new species did not form any extraintestinal stages in the host. It also did not produce endomastigotes, indispensable for transmission in other Phytomonas spp. These observations, along with the fact that P. bidens overwinters at the egg stage, led us to the conclusion that the examined infections with P. borealis were non-specific. Strikingly, the flagellates from the Novgorod population contained prokaryotic endosymbionts, whereas the parasites from the second locality were endosymbiont-free. This is a first case documenting presence of intracellular symbiotic bacteria in Phytomonas spp. We suggest that this novel endosymbiotic association arose very recently and did not become obligate yet. Further investigation of P. borealis and its intracellular bacteria may shed light on the origin and early evolution of endosymbiosis in trypanosomatids., Anna I. Ganyukova, Alexander O. Frolov, Marina N. Malysheva, Viktoria V. Spodareva, Vyacheslav Yurchenko and Alexei Yu. Kostygov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1819. A novel experimental model of acute respiratory distress syndrome in pig
- Creator:
- Otáhal, M., Mlček, M., Vítková, I., and Kittnar, O.
- Type:
- article, model:article, and TEXT
- Subject:
- Acute respiratory distress syndrome, Animal model, Pig, and Lavage
- Language:
- English
- Description:
- Acute respiratory distress syndrome (ARDS) is severe medicalcondition occurring in critically ill patients and with mortality of 33-52 % is one of the leading causes of death in critically ill patients. To better understand pathophysiology of ARDS and to verify novel therapeutical approaches a reliable animal model is needed. Therefore we have developed modified lavage model of ARDS in the pig. After premedication (ketamine and midazolam)35 healthy pigs were anesthetized (propofol, midazolam, morphin, pipecuronium) and orotracheally intubated and ventilated. Primary ARDS was induced by repeated cycles of lunglavage with a detergent Triton X100 diluted in saline (0.03 %) heated to 37 °C preceded by pre -oxygenation with 100 % O2. Single cycle included two subsequent lavages followed by detergent suction. Eachcyclewas followed by hemodynamic andventilation stabilization for approx. 15 min, with eventualadministration of vasopressors according to an arterial bloodpressure. The lavage procedure was repeated until the paO2/FiO2index after stabilization remained below 100 at PEEP 5 cm H2O. In 33 pigs we have achieved the desired degree of severe ARDS(PaO2/FiO2<100). Typical number of lavages was 2-3 (min. 1,max.5). Hemodynamictolerance and the need for vasopressors were strongly individual. In remainingtwo animalsan unmanageable hypotension developed. For other subjects theexperimental ARDS stability was good and allowed reliablemeasurement for more than 10 h. The present model of theARDS is clinically relevant and thus it is suitable for further research of the pathophysiology and management of this serious medical condition.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1820. A Novel Framework to Alleviate Dissemination of XSS Worms in Online Social Network (OSN) using View Segregation
- Creator:
- Chaudhary, P. and Gupta, B. B.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Cross-Site Scripting (XSS) worms, online social network security, and URI links
- Language:
- English
- Description:
- In this paper, we propose a client-server based framework that alleviates the dissemination of XSS worms from the OSN. The framework initially creates the views corresponding to retrieved request on the server-side. Such views indicate that which part of the generated web page on the server can be accessed by user depending on the generated Access Control List (ACL). Secondly, JavaScript attack vectors are retrieved from the HTTP response by referring the blacklist repository of attack vectors. Finally, injection of sanitization primitives will be done on the client-side in place of extracted JavaScript attack vectors. The framework will perform the sanitization on such attack vectors strictly in a context-aware manner. The experimental testing of our framework has performed on the two platforms of open source OSN-based web applications. The observed detection rate of JavaScript attack vectors was effective and acceptable as compared to other existing XSS defensive methodologies. The proposed framework has optimized the method of auto-context-aware sanitization in contrast to other existing approaches and hence incurs a low and acceptable performance overhead.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public