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Amer Mešanović, Amer Mešanović, U. Münz, A. Szabo, M. Mangold, J. Bamberger, Mitchell Metzger, C. Heyde et al.

Reliable and secure operation of power systems becomes increasingly challenging as the share of volatile generation rises, leading to largely changing dynamics. Typically, the architecture and structure of controllers in power systems, such as voltage controllers of power generators, are fixed during the design and buildup of the network. As replacing existing controllers is often undesired and challenging, setpoint adjustments, as well as tuning of the controller parameters, are possibilities to counteract large disturbances and changing dynamics. We present an approach for fast and computationally efficient adaptation of parameters of structured controllers based on H-infinity optimization, also referred to as structured H-infinity controller synthesis, tailored towards power systems. Conditions are established that guarantee that the approach leads to stability.The results are verified in a testbed microgrid consisting of six inverters and a load bank, as well as simulation studies. The proposed method improves the system robustness, as well as the time-response to step disturbances and allows structured controller tuning even for large networks.

27. 10. 2019.
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S. Vranić, Z. Gatalica

A carcinoma with apocrine differentiation arising from the sweat glands. It presents as single or multiple nodular lesions which may be ulcerated or hemorrhagic and is usually in the axilla and less often in the anogenital region. It grows in the dermis and infiltrates subcutaneous tissues. It is characterized by the presence of large cells with abundant eosinophilic cytoplasm and large often vesicular nuclei. Most cases are slow growing tumors and have a prolonged course. Qeios · Definition, February 7, 2020

D. Kosini, C. Saidou, E. Nukenine, I. Sugri, W. Mojeremane, T. Mathowa, Ofentse Moseki, G. M. Legwaila et al.

M. Grabner, A. Souvent, N. Suljanovic, A. Košir, B. Blazic

There has been an increasing trend of integrating photovoltaic power plants (PVs). One of the important challenges for distribution system operators is to evaluate the total installed power of a PV that a particular network can host (or PV hosting capacity) while keeping voltage and element constraints within required limits. The major drawback of the existing methods for calculating PV hosting capacity is that they use the same installed power of the PV systems for all simulated PVs, as these methods do not use external data sources about building roofs. As a consequence, this has a significant impact on the final accuracy of the results. This paper presents a probabilistic methodology for calculating the PV hosting capacity in low voltage (LV) networks. The main contribution of this paper is the improved modeling of PV generation using actual building roof data when calculating the PV hosting capacity, as every building is treated according to its actual solar potential. Monte Carlo simulations with incorporated stochastic consumption and PV generation models are utilized for load flow calculations of the actual LV network. The simulation results presented in this paper prove that the proposed methodology increases the accuracy of the final PV hosting capacity calculations.

L. Fachal, H. Aschard, J. Beesley, Daniel R. Barnes, Jamie Allen, S. Kar, K. Pooley, J. Dennis et al.

Genome-wide association studies have identified breast cancer risk variants in over 150 genomic regions, but the mechanisms underlying risk remain largely unknown. These regions were explored by combining association analysis with in silico genomic feature annotations. We defined 205 independent risk-associated signals with the set of credible causal variants in each one. In parallel, we used a Bayesian approach (PAINTOR) that combines genetic association, linkage disequilibrium and enriched genomic features to determine variants with high posterior probabilities of being causal. Potentially causal variants were significantly over-represented in active gene regulatory regions and transcription factor binding sites. We applied our INQUSIT pipeline for prioritizing genes as targets of those potentially causal variants, using gene expression (expression quantitative trait loci), chromatin interaction and functional annotations. Known cancer drivers, transcription factors and genes in the developmental, apoptosis, immune system and DNA integrity checkpoint gene ontology pathways were over-represented among the highest-confidence target genes. Fine-mapping of causal variants and integration of epigenetic and chromatin conformation data identify likely target genes for 150 breast cancer risk regions.

Rijad Dedeić, Ensar Mekić

The purpose of this study is to develop theoretical grounds to investigate relationship between different leadership styles of sport managers and achievement motivation of practitioners in judo sport of Bosnia and Herzegovina (B&H). Practitioners’ perceptions on sport managers’ leadership styles and achievement motivation of practitioners can be used to investigate the mentioned relationships. Methodology used to develop the theoretical model is literature review. Once relevant studies were carefully analyzed, the variables have been defined, relationships among them were explained, and hypotheses were proposed. The validation of proposed model may provide useful findings for sport managers in martial arts, especially judo coaches. Furthermore, practical implications of this study could help sport managers engaged in martial arts to determine more functional leadership style which will result in more effective results. The validation of the proposed model is strongly recommended to different researchers, in different regions at different times.

Negra Hadžić Metjahić, M. Vidovič, J. Cakar, M. Dzehverovic, A. Pilav, S. Dogan, D. Marjanović

This study was conducted to confirm preliminary anthropological research indicating the specificity of isolated Selška Valley populations and implement clear mapping of genetic distances between neighboring populations and similar "inland island" populations from the region. The sample consisted of 86 unrelated individuals born in the Selška Valley from the lowland villages (Bukovica, Ševlje, Dolenja Vas, Selca, Železniki and Zali Log) and the mountain villages (Podlonk, Prtovč, Spodnje Danje, Zgornja Sorica and Spodnja Sorica). The for mentioned 15 STR loci (D3S1358, TH01, D21S11, D18S51, Penta E, D5S818, D13S317, D7S820, D16S539, CSF1PO, Penta D, vWA, D8S1179, TPOX and FGA) were analyzed and statistical analysis was applied to determine population-genetics and forensic parameters. The frequencies of 15 STR loci from isolated populations of Slovenian villages, Slovenia, Bosnian mountain villages and Bosnia and Herzegovina were analyzed to calculate genetic distances between them. Our results confirmed a similar genetic pattern between the Selška Valley mountain villages and Slovenian general population as well as Bosnian mountain villages and general Bosnian population. Even if the sample size was relatively small and examined populations were geographically isolated, observed genetic variation within the whole population was relatively high and comparable with neighboring populations. Additional analysis proved that the Selška Valley population is genetically closest to the Slovenian and Austrian populations. On the other hand, comparison with similarly patterned populations confirmed that this population could be recognized as "inland island" population in genetic terms.

M. Arslan, J. Schaap, P. P. Rood, K. Nieman, R. Budde, M. Attrach, E. Dubois, A. Dedic

Aims: Coronary computed tomography angiography is increasingly employed in the emergency department for suspected acute coronary syndrome patients. The HEART score has been proposed for initial risk stratification in these patients. The aim of this study was to investigate the diagnostic value and efficiency of the HEART score before coronary computed tomography angiography. Methods and results: We included patients suspected of acute coronary syndrome who underwent coronary computed tomography angiography in the emergency department. Based on the HEART score, patients were stratified as low-risk (HEART≤3), intermediate-risk (HEART4–6) and high-risk (HEART≥7). We assessed coronary computed tomography angiography for the presence of significant coronary artery disease (>50% stenosis). The primary outcome, the level of major adverse cardiac events, was a composite endpoint of all-cause mortality, acute coronary syndrome or coronary revascularisation within 30 days. The study population consisted of 340 patients (mean age: 55.6±10.1 years, 44.7% women), major adverse cardiac events occurred in 45 (13.2%) patients. The incidence of major adverse cardiac events in patients stratified as low-risk (35.0%), intermediate-risk (56.8%) and high-risk (8.2%) was 3.4%, 12.4% and 60.7%, respectively. All four low-risk patients with major adverse cardiac events had a HEART score of three. An algorithm where coronary computed tomography angiography is reserved for patients with HEART 3–6 resulted in a sensitivity of 97.8%, specificity of 84.1%, negative predictive value of 99.6% and positive predictive value of 48.4%, while reducing the need for coronary computed tomography angiography by 22% (n=75). Conclusion: The predictive value of coronary computed tomography angiography for 30-day major adverse cardiac events in suspected acute coronary syndrome patients is good, and reserving coronary computed tomography angiography for HEART score 3–6 patients reduces the number of needed coronary computed tomography angiograms without affecting diagnostic accuracy.

Background: This study aimed to investigate the accuracy and reliability of a free mobile heart rate variability (HRV) application in measuring HRV. Methods: Twelve females and 12 males underwent five-minute simultaneous HRV recording from electrocardiogram (ECG) and chest strap connected to a free mobile HRV application (HRVapp) in a supine position. HRV data from ECG and HRVapp were used to examine accuracy and reliability via relative error and intraclass correlation coefficient respectively. Results: The natural log of the square root of the mean of the sum of the squares of differences between adjacent normal to normal intervals (lnRMSSD) exhibited accuracy and high reliability in HRVapp. Conclusion: lnRMSSD in HRVapp can serve as an alternative, low-cost technology for measurement of autonomic activity.

Stevan Djenadic, D. Ignjatović, M. Tanasijević, U. Bugarić, I. Jankovič, T. Šubaranović

Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the coefficient of time use of the machine. This approach is not good enough because it does not go into the structure of the availability itself and requires a high level of IT support in system monitoring. In this sense, this paper will use the fuzzy theory and the corresponding analytic hierarchy process (AHP) multi-criteria analysis to present a conceptual and mathematical model for the assessment of availability based on expert judgment. The model will be shown in the case study (on the example) of bulldozers working in the open-pit lignite mine.

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