ABSTRACT Numerical modeling of detonation by the Wood-Kirkwood detonation theory requires the detonation front curvature radius to be specified as an input parameter. In this work we present two empirical equations for the estimation of the curvature radii of various explosives. The equations are derived based on a large number of literature-reported experimental data on the detonation front curvature radii as a function of charge radii and failure radii. The proposed equations predict the front curvature radii with the root mean square error of about 30%, which is a significant improvement compared to previously proposed empirical equations.
The efficiency of transport companies is a very important factor for the companies themselves, as well as for the entire economic system. The main goal of this paper is to develop an integrated model for determining the efficiency of representative transport companies over a period of eight years. An original model was developed that includes the integration of DEA (Data Envelopment Analysis), PCA (Principal Component Analysis), CRITIC (Criteria Importance Through Inter criteria Correlatio), Entropy and MARCOS (Measurement Alternatives and Ranking according to the COmpromise Solution) methods in order to determine the final efficiency of transport companies based on 10 input–output parameters. The results showed that the most efficient business performance was achieved in the period 2014–2017, followed by slightly less efficient results. Then, extensive sensitivity analysis and comparative analysis were performed, which confirmed, to some extent, the previously obtained results. In the sensitivity analysis, 30 scenarios with changes in the weights of criteria were created, while the comparative analysis was carried out with three other MCDM (Multi-Criteria Decision-Making) methods. Finally, the rank correlation index was determined using the Spearman and WS (Wojciech Salabun) correlation coefficients. According to the final results, very efficient years can be separated that can be the benchmark for furthering the business.
The increasing availability of high-quality genome assemblies raised interest in the characterization of genomic architecture. Major architectural elements, such as common repeats and segmental duplications (SDs), increase genome plasticity that stimulates further evolution by changing the genomic structure and inventing new genes. Optimal computation of SDs within a genome requires quadratic-time local alignment algorithms that are impractical due to the size of most genomes. Additionally, to perform evolutionary analysis, one needs to characterize SDs in multiple genomes and find relations between those SDs and unique (non-duplicated) segments in other genomes. A naïve approach consisting of multiple sequence alignment would make the optimal solution to this problem even more impractical. Thus there is a need for fast and accurate algorithms to characterize SD structure in multiple genome assemblies to better understand the evolutionary forces that shaped the genomes of today. Here we introduce a new approach, BISER, to quickly detect SDs in multiple genomes and identify elementary SDs and core duplicons that drive the formation of such SDs. BISER improves earlier tools by (i) scaling the detection of SDs with low homology to multiple genomes while introducing further 7–33×\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\times$$\end{document} speed-ups over the existing tools, and by (ii) characterizing elementary SDs and detecting core duplicons to help trace the evolutionary history of duplications to as far as 300 million years. BISER is implemented in Seq programming language and is publicly available at https://github.com/0xTCG/biser.
Purpose This paper aims to address the user perspective about usability, security and use of five authentication schemes (text and graphical passwords, biometrics and hardware tokens) from a population not covered previously in the literature. Additionally, this paper explores the criteria users apply in creating their text passwords. Design/methodology/approach An online survey study was performed in spring 2019 with university students in Mexico and Bosnia and Herzegovina. A total of 197 responses were collected. Findings Fingerprint-based authentication was most frequently perceived as usable and secure. However, text passwords were the predominantly used method for unlocking computer devices. The participants preferred to apply personal criteria for creating text passwords, which, interestingly, coincided with the general password guidelines, e.g. length, combining letters and special characters. Originality/value Research on young adults’ perceptions of different authentication methods is driven by the increasing frequency and sophistication of security breaches, as well as their significant consequences. This study provided insight into the commonly used authentication methods among youth from two geographic locations, which have not been accounted for previously.
Saeh, Bassam, Nadnaravni jezik Kur'ana, s engleskog preveo: Munir Drkić. Sarajevo: Centar za napredne studije, 2018. str. 104. ISBN 978-9958-022-68-5.
Background The objectives of the study were to investigate the organizational characteristics of acute care facilities worldwide in preventing and managing infections in surgery; assess participants’ perception regarding infection prevention and control (IPC) measures, antibiotic prescribing practices, and source control; describe awareness about the global burden of antimicrobial resistance (AMR) and IPC measures; and determine the role of the Coronavirus Disease 2019 pandemic on said awareness. Methods A cross-sectional web-based survey was conducted contacting 1432 health care workers (HCWs) belonging to a mailing list provided by the Global Alliance for Infections in Surgery. The self-administered questionnaire was developed by a multidisciplinary team. The survey was open from May 22, 2021, and June 22, 2021. Three reminders were sent, after 7, 14, and 21 days. Results Three hundred four respondents from 72 countries returned a questionnaire, with an overall response rate of 21.2%. Respectively, 90.4% and 68.8% of participants stated their hospital had a multidisciplinary IPC team or a multidisciplinary antimicrobial stewardship team. Local protocols for antimicrobial therapy of surgical infections and protocols for surgical antibiotic prophylaxis were present in 76.6% and 90.8% of hospitals, respectively. In 23.4% and 24.0% of hospitals no surveillance systems for surgical site infections and no monitoring systems of used antimicrobials were implemented. Patient and family involvement in IPC management was considered to be slightly or not important in their hospital by the majority of respondents (65.1%). Awareness of the global burden of AMR among HCWs was considered very important or important by 54.6% of participants. The COVID-19 pandemic was considered by 80.3% of respondents as a very important or important factor in raising HCWs awareness of the IPC programs in their hospital. Based on the survey results, the authors developed 15 statements for several questions regarding the prevention and management of infections in surgery. The statements may be the starting point for designing future evidence-based recommendations. Conclusion Adequacy of prevention and management of infections in acute care facilities depends on HCWs behaviours and on the organizational characteristics of acute health care facilities to support best practices and promote behavioural change. Patient involvement in the implementation of IPC is still little considered. A debate on how operationalising a fundamental change to IPC, from being solely the HCWs responsibility to one that involves a collaborative relationship between HCWs and patients, should be opened.
We study the flavor structure of the lepton and baryon number-conserving dimension-6 operators in the Standard Model effective field theory (SMEFT). Building on the work of [1], we define several well-motivated flavor symmetries and symmetry-breaking patterns that serve as competing hypotheses about the ultraviolet (UV) dynamics beyond the SM, not far above the TeV scale. In particular, we consider four different structures in the quark sector and seven in the charged lepton sector. The set of flavor-breaking spurions is (almost) always taken to be the minimal one needed to reproduce the observed charged fermion masses and mixings. For each case, we explicitly construct and count the operators to the first few orders in the spurion expansion, providing ready-for-use setups for phenomenological studies and global fits. We provide a Mathematica package SMEFTflavor (https://github.com/aethomsen/SMEFTflavor) to facilitate similar analyses for flavor symmetries not covered in this work.
Palmberger, Monika, How Generations Remember: Conflicting Histories and Shared Memories in Post-War Bosnia and Herzegovina. London: The Palgrave Macmillan, 2016. pp. vii+254. ISBN 978-1-137-45063-0.
Sebina Sivac-Bryant, Re-Making Kozarac: Agency, Reconciliation and Contested Return in Post-War Bosnia, Palgrave Studies in Com- promise after Conflict, 2016. Str. 214, ISBN 978-1-137-58838-8.
Institucije islamske civilizacije – izabrani članci iz Türkiye Diyanet Vakfı İslâm Ansiklopedisi, Ahmet Alibašić, Munir Mujić (ur.), Sarajevo: Čentar za napredne studije, 2017, str. 712, ISBN 978-9958-022-50-0.
Underground diesel exhaust exposure is an occupational health risk. It is not known how recent intensified emission legislation and use of renewable fuels have reduced or altered occupational exposures. We characterized these effects on multipollutant personal exposure to diesel exhaust and underground ambient air concentrations in an underground iron ore mine. Full-shift personal sampling (12 workers) of elemental carbon (EC), nitrogen dioxide (NO2), polycyclic aromatic hydrocarbons (PAHs), and equivalent black carbon (eBC) was performed. The study used and validated eBC as an online proxy for occupational exposure to EC. Ambient air sampling of these pollutants and particle number size distribution and concentration were performed in the vicinity of the workers. Urine samples (27 workers) were collected after 8 h exposure and analyzed for PAH metabolites and effect biomarkers (8-oxodG for DNA oxidative damage, 4-HNE-MA for lipid peroxidation, 3-HPMA for acrolein). The personal exposures (geometric mean; GM) of the participating miners were 7 µg EC m−3 and 153 µg NO2 m−3, which are below the EU occupational exposure limits. However, exposures up to 94 µg EC m−3 and 1200 µg NO2 m−3 were observed. There was a tendency that the operators of vehicles complying with sharpened emission legislation had lower exposure of EC. eBC and NO2 correlated with EC, R = 0.94 and R = 0.66, respectively. No correlation was found between EC and the sum of 16 priority PAHs (GM 1790 ng m−3). Ratios between personal exposures and ambient concentrations were similar and close to 1 for EC and NO2, but significantly higher for PAHs. Semi-volatile PAHs may not be effectively reduced by the aftertreatment systems, and ambient area sampling did not predict the personal airborne PAHs exposure well, neither did the slightly elevated concentration of urinary PAH metabolites correlate with airborne PAH exposure. Miners’ exposures to EC and NO2 were lower than those in older studies indicating the effect of sharpened emission legislation and new technologies. Using modern vehicles with diesel particulate filter (DPF) may have contributed to the lower ambient underground PM concentration and exposures. The semi-volatile behavior of the PAHs might have led to inefficient removal in the engines aftertreatment systems and delayed removal by the workplace ventilation system due to partitioning to indoor surfaces. The results indicate that secondary emissions can be an important source of gaseous PAH exposure in the mine.
The possibility of establishing a transparent public procurement process through the inclusion of protected transparent digital technologies or platforms, such as blockchain technology, represents a significant step forward in the field of public procurement. Furthermore, if we add to this idea the Ethereum network and the ability to create applications that run on this network, such as smart contracts, the procurement process can be made much more objective and transparent to all participants in the process. The proposed model presented in this paper consists of two smart contracts. Each one of them has its own basic building blocks used for different phases of the public procurement process, from the definition of security access polices for different parts of procurement contract, public procurement procedure, bidding by interested bidders, evaluation of bids and the final publication of the results. Elements of the proposed system have been analyzed and presented and some of the further development plans have been formulated.
Short circuit faults are one of the most common disturbances in power systems that occur because of insulation failure due to a sudden overvoltage condition caused by lightning, switching operations, insulation contamination, etc. Medium voltage power distribution networks use different methods for grounding the neutral point. Influences of these grounding methods on the characteristics of single-phase short circuit fault are discussed in this paper on the example of substation “Bugojno”. Modeling and simulation are implemented in EMTP-RV (Electromagnetic Transient Program-Restructured Version) software. Data recorded by protection system during normal operation and three-phase short circuit fault in the substation are analyzed and used for comparison with simulation results to validate developed model of the observed part of power system. This validated model was then used to analyze the effects of neutral point grounding methods on the characteristics of single-phase short circuit fault.
Transient events, especially those related to the short circuit faults, are the main causes of power distribution lines outages. This paper is dedicated to the analysis of three-phase short circuit fault and its impact to the real 20 kV power distribution lines. One of the most important parts of Bosnia and Herzegovina's power system was monitored and analyzed. Short circuit currents and voltages were obtained by using the power distribution lines numerical protection system measurements from the moment of fault occurrence to the moment when the faulty line was switched off. Part of the power system of interest was modeled in EMTP-RV (Electromagnetic Transient Program - Restructured Version) software which is standardized software for transient analyses. Several simulations were conducted to perform fault analysis. Measured data and simulation results were compared.
Overvoltages are unpredictable and extremely dangerous for the electric power system. The causes of overvoltages are different, but lightning is considered as one of the most serious causes of overvoltages. High voltage substations are one of the main parts of the power system whose faults caused by overvoltages can lead to outage of large part of power system. Therefore, overvoltage protection of a high voltage substation is very important. In order to protect the substation as much as possible from the effects of the overvoltages, it is necessary to implement elements that can help reduce these effects, for example surge arresters. This paper presents the effects of the use of surge arresters in high voltage, gas SF6 insulated substation, modeled in the EMTP-RV (Electromagnetic Transient Program-Restructured Version) software. An accurate representation of lightning surge incoming in the substation is very important because it strongly affects the design of overvoltage protection system. In this paper parameters of lightning strikes are determined using Sigma Slp software.
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