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I. Atanasov, A. Nikolov and E. Pencheva

Abstract

Machine-to-Machine communications (M2M) allow connected devices to exchange data and perform actions without human intervention. Different M2M applications have different quality of service (QoS) requirements. The dynamic QoS control is critical for applications like video surveillance, transportation services, and industrial control. The provided QoS depends on device connectivity. Connectivity management provides centralized management of M2M devices and connections. The paper studies model aspects of QoS management for connected M2M devices by means of connectivity management. Models for connectivity management are suggested, formally described and verified. The capabilities for device connectivity management are used to model the behavior of autonomous agent for dynamic QoS control.

Open access

E. Nikolov, N. Nikolova and B. Grasiani

Abstract

The work proposed analytical modeling the processes in laboratory pneumatic FESTO-model. The characteristics of the pro-posed analytical model are simulated and analyzed. Systems for control of laboratory installation are synthesized. Designing control systems are modeled and their performance is analyzed. Is confirmed and proven their efficiency.

Open access

E. Nikolov, N. G. Nikolova and B. Grasiani

Abstract

The present study systematizes certain methods for analysis at priori un-certainty and proposes new methods for analy-sis of the filtration features of the repetitive gain scheduling control sys-tems under the conditions of periodic harmonic interference. For analysis of the fil-tering features of the repetitive gain scheduling control systems, the following methods have been proposed and applied to a particular example: temporal analy-sis with “test” periodic im-pacts in nomi-nal parametric mode and frequency analysis, using the method of the alge-braic derivative.

Open access

Nikolay K. Balgaranov, Lachezar S. Nikolov, Nadia I. Kolarova-Yaneva, Vania N. Nedkova, Kristina Ts. Tabakova and Viktor E. Donev

Summary

Asthma and allergic rhinitis are common in childhood. Establishing sensitization to aeroallergens is crucial to effectively prevent exacerbation of these respiratory allergic diseases. The study aimed to evaluate sensitization to the most common aeroallergens in children with asthma and allergic rhinitis.We establishedacorrelation between patients sensitized to indoor, outdoor and simultaneously to both allergens. The study population consisted of 276 patients (168 boys and 108 girls) ages 4 to 16 years with asthma (A) and allergic rhinitis (AR). Skin prick tests were performed with 21 commercial allergen extracts: pollens, mites, epithelia and insects, and molds. We found that 217 patients were sensitized to at least one aeroallergen: 117 patients hadapositive result to mites, 92 to pollens, 72 to epithelia and insects, and 63 - to mold allergens. Dermatophagoides pteronyssinus was the most prevalent aeroallergen. Sensitized only to indoor allergens were 104 patients, 60 - only to outdoor allergens, and 53 were sensitized to both. Mites were the most frequent aeroallergens in children with Aand AR. Lately there has been foundasignificant increase in rates of sensitization to mold allergens, especially to Alternaria alternata. Our study has confirmed the dominant role of indoor allergens in children with respiratory allergic diseases.