Ante Marušić

Mycobacterium xenopi pulmonary disease – Epidemiology and clinical features in non-immunocompromised patients

OBJECTIVES The genus Mycobacterium has more than 120 well-characterized species. Although the incidence of tuberculosis has decreased over the studied period, other, non-tuberculous mycobacteria (NTM) are isolated more often. Since, Mycobacterium xenopi is the most frequent NTM isolate in Croatia we studied its epidemiology and clinical relevance. METHODS We performed a retrospective study over a 25-year period determining epidemiology, radiological findings and clinical importance of M. xenopi infection, obtaining data from archives in health care institutions from all over the country. RESULTS We detected 40 patients with a positive isolate of M. xenopi. Twenty-four patients met American Thoracic Society criteria for pulmonary disease. Eighteen (90%) of treated patients were male, on average 61.7 years old. Nineteen (95%) patients lived in towns. Most of them had comorbid disease, 18 (90%), with chronic obstructive pulmonary disease (COPD) being the most frequent, found in 11 (55%) patients. All patients were immunocompetent. We found COPD as the most frequent comorbid disease in the group of patients with worse treatment response (n=8; 80%), while in patients with good treatment response COPD was less frequent (n=3; 30%). Differences in the proportions of patients with COPD were significant (p=0.037). CONCLUSION In patients with M. xenopi pulmonary infection, COPD is a predisposing condition, and as a comorbid disease, is an important prognostic factor for treatment response.

Integrating DPWS and OPC UA device-level SOA features into IEC 61850 applications

Flexible and adaptable integration of diverse devices and applications used for power system automation is one of the key prerequisites for accelerated and future-proof Smart Grid deployment. International standard IEC 61850 has been globally accepted as one of the prime movers of successful and interoperable Smart Grid integration. However, current IEC 61850 definition lacks the integration capability based on device-level Service Oriented Architecture (SOA) paradigm. SOA is widely applied for enterprise integration and one of the envisioned paradigms for industrial automation domain. Implementing IEC 61850 systems according to device-level SOA principles could significantly facilitate standards-compliant device integration and accelerate overall Smart Grid automation deployment. This article presents a solution for integrating device-level SOA principles into IEC 61850 architecture. Two most prominent device-level SOA technologies, Devices Profile for Web Services (DPWS) and OPC Unified Architecture (OPC UA), have been analyzed according to IEC 61850 system requirements. As a result of analysis, a novel middleware platform which integrates both DPWS and OPC UA features into IEC 61850 applications is presented. The proposed solution provides an extensible Smart Grid application framework based on state-of-the-art industrial automation standards thus allowing accelerated Smart Grid integration.

Transmission line impedance estimation based on PMU measurements

State estimation is one of the most important network management functions, responsible for determining the actual state of the power network based on the network model, available telemetry (analog measurements and digital device statuses) and pseudo measurements. Phasor measurement units (PMUs) provide valuable instantaneous information regarding power system stability and security, and thus have the potential to improve the reliability of the state estimator. Also, measured synchrophasors can be used for transmission line impedance estimation, which results in more accurate power system state estimation, in comparison with the traditional approach that uses catalogue values of the transmission line impedance.

Comparison of various neural network models applied to adaptive distance protection

This paper elaborates settings and modification of the operating characteristic of adaptive distance relays which protect a transmission line between two terminals. Operating characteristic should have such shape to satisfy all conditions in the power system. However it is known that there is no combination of characteristics which can satisfy all possible conditions. So the only solution is modification of the operating characteristic. Solution of this problem involves two types of neural networks, multilayered perceptron and the self-organizing neural network, the so called Kohonen network. Here the authors consider a two-terminal transmission line, confirm that fault resistance and location of faults can produce erroneous relay function and finally suggest ways to ensure the generation of the correct signal for relay operation. With the simple simulation, the authors present the advantages of the particular models and the credibility of the developed models.

Nontuberculous Mycobacterial Pulmonary Disease

Tuberculosis (TB) is an infectious and transmissible disease caused by Mycobacterium tuberculosis and closely related mycobacterial species (M. bovis, M. africanum, and M. microti). These species, obligate pathogens, compose what is known as the M. tuberculosis complex. Nontuberculous mycobacterial (NTM) species are mycobacterial species other than those belonging to the Mycobacterium tuberculosis complex. Nontuberculous mycobacteria are generally free-living organisms that are ubiquitous in the environment. There have been more than 140 NTM species identified. In 1959, Runyon proposed a classification of NTM into four major groups, based on growth rate and colony pigmentation (Runyon EH , 1959).

A computerized fault location process for overhead radial distribution feeders

This paper describes an automated system for fault location in distribution networks including information recorded by protection devices as so as knowledge about feeder configuration, quality of network, type of terrain, human experience, fault statistics etc. Fuzzy set theory was applied to deal with uncertainties and inexactness during fault location process (FLP) and as a support in decision making

Multi-variable series infinite impulse response least squares algorithm

The comparison is discussed between the multi- variable LSQ algorithm and newly developed LSQ IIR algorithm; the operation characteristics of both algorithms are analyzed. The obtained analyses results indicate the advantages of LSQ IIR algorithm over the LSQ one. The LSQ IIR algorithm is used in extracting fundamental components of voltage and current waveforms from which the amplitudes and phases of each component are obtained.

Electrical protection selectivity in auxiliary DC installations in power plants and substations

The goal of this work is to present an adequate model that will allow analysis, dimensioning and control of auxiliary DC installations in power plants, first of all from the protection device point of view. A general mathematical model of auxiliary DC installations in power plants was developed in order to be used for analyzing short circuit conditions. It was concluded that the transient state during the short circuit has to be taken into account. The essence of this new approach is the new mathematical model which takes into consideration not only resistances, but inductances and capacities of auxiliary DC elements as well as the active network in front of the rectifier. Based on this mathematical model, an original program package was developed and used for analyzing and dimensioning auxiliary DC installations in power plants. The results obtained are relevant for dimensioning all elements of auxiliary DC installations, particularly when protection devices are considered.

Transient short-circuit currents in auxiliary DC installations in power plants and substations

The original contribution of this work is contained in the following statements. A general mathematical model of auxiliary DC installations in power plants was developed in order to be used for analyzing short circuit conditions according to the references K. Albert et al. (1996). It was concluded that the transient state during short circuit has to be taken into account. The essence of this new approach is the new mathematical model which takes into consideration not only resistances, but inductances and capacities of auxiliary DC elements as well as the active network in front of the rectifier. Based on this mathematical model, an original program package was developed and used for analyzing and dimensioning auxiliary DC installations in power plants according to A. Berizzi et al. (1998). The results obtained by means of the program package are relevant for dimensioning all elements of auxiliary DC installations, particularly when protection devices are considered.

Wake Characteristics of Ice-Accreted Cylindrical Bars in a Cross-Flow at Subcritical Reynolds Numbers

AbstractIce accretion can considerably alter aerodynamic characteristics of bridge cables. The present study focuses on flow characteristics in the cable wake for three arrangements of ice accretio...