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he paper proposes a methodology for defining the optimal solution for the integrated usage of cogeneration and rooftop photovoltaics. The purpose is to minimize CO₂ emissions in industrial plants. The methodology is founded on the integral use of energy audit techniques (analyzing energy and material flows in a production process and the dependence of electricity and heat consumption on a production volume) and mathematical optimization (linear programming). In accordance with the obtained consumption profiles, technical limitations, and legal regulations, the potential for installing rooftop photovoltaic (PV) panels at appropriate locations and the implementation of appropriate cogeneration technologies were analysed. The proposed methodology was tested on a local margarine production facility. The integrated application of cogeneration (gas engines) and photovoltaics can reduce the current CO₂ emission by 56% if PV panels are installed on the entire accessible rooftop surface, i.e. up to 44.5% if 150 kW PV panels are installed as the new national regulation proposes.

Background/Aim. Achieving good metabolic control, which plays a key role in reducing or preventing macrovascular and microvascular complications of diabetes mellitus (DM), requires continuous patient involvement in the self-management of DM. This continued engagement, which makes type 2 DM (T2DM) one of the most physically and emotionally demanding diseases, can become, at certain periods of life, extremely severe and lead to emotional distress (symptoms of depression and DM-related distress) and d-terioration of metabolic control. The aim of this study was to examine the association and influence of behavioral and psychological factors on the metabolic control of patients with T2DM. Methods. The research was conducted as a descriptive-analytic cross-sectional study. The method of random sampling included 324 subjects with T2DM in the research. The values of biochemical parameters of metabolic control were measured by standard laboratory methods. Blood pressure was measured two times, and the arithmetic mean was calculated. Anthropometric measurement was performed, and body mass index (BMI) was calculated. Attitudes toward medication adherence, adherence to dietary recommendations, level of physical activity, presence of depressive symptoms, and level of DM-related distress were examined using standardized questionnaires. Results. The target values of metabolic control parameters were reached by 21.6% of respondents. Multivariate analysis as predictors of poor metabolic control identified obesity, non-adherence toward dietary recommendations, insulin therapy, low level of physical activity, and clinically significant DM-related distress. Conclusion. Routine application of the questionnaire used in this study in the initial stages or critical moments of the disease can assess patients’ attitudes and knowledge about behavioral determinants of DM self-management and timely detect psychological conditions that affect them. It would be realistic to expect that such a comprehensive holistic approach would contribute to a lower incidence of complications and better metabolic control of T2DM.

The aim of this research is to propose the two-stage model to select a set of failures that need to be eliminated or reduced which leads to improved reliability and effectiveness of the manufacturing process in the automotive industry. In the first stage, uncertainties under the relative importance of risk factors and costs of manufacturing process downtime due to failure are modeled by type 2 fuzzy sets. The weights vector of risk factors is obtained by analytical hierarchical Process which is extended with type 2 fuzzy sets. Evaluation of risk factors at the level of each identified failure is based on failure mode and effect analysis which is widely used in practice. Determining the set of failures to be eliminated is set as a knapsack problem. The linear fitness function is defined as the ratio of the overall risk priority index and total costs. Maintenance costs incurred due to the realization of failure are limited by the available budget and in this knapsack problem are presented by a linear inequality. The solution to this problem is found by using the Genetic Algorithm and Variable Neighborhood Search. The model is verified with real-life data originating from automotive companies that exist in Serbia. Authors have managed to obtain suitable results on different knapsack problem instances. It is shown that the enhancement of the manufacturing process can be based on the proposed model. [ABSTRACT FROM AUTHOR]

Introduction/purpose: The paper presents the method of applying multicriteria decision-making methods in order to improve shooting and select the most favorable conditions for shooting. Alternatives were ranked by individual multi-criteria decision-making methods AHP and VIKOR by experts, and then the most favorable alternative was selected using the Borda method of group decision making. The aim of the work is to select the most efficient way of shooting with minimal human fatigue, consumption of movable things and in the shortest possible time through a combination of multi-criteria decision-making methods, which will ensure the accuracy and precision of the rifle for subsequent shooting and other operations. Methods: The paper presents one of the ways of using multidisciplinary methods of multi-criteria decision making for a specific problem in the field of tactics with weapon systems. Experts from the field of armaments, using the AHP and VIKOR methods of individual multi-criteria decision making, selected the most favorable alternative in accordance with four given criteria. Then, by applying the Borda method of group decision making, the the most favorable alternative was selected - the most favorable conditions for the execution of preparatory shooting at serial number one with a 12.7 mm long range rifle. The alternatives are four shootings, namely, two ways of performing preparatory shooting with a 12.7 mm long range rifle at serial number one, one from the current Instructions and Program of Shooting with Infantry Weapons and the other newly proposed method, as well as two ways of realizing shooting for testing the accuracy and precision of a long range rifle. Results: The selection of the most effective conditions for the execution of the first initial preparatory shooting at serial number one with a long range rifle, which will ensure maximum accuracy of the weapon and the minimum consumption of resources - time, ammunition, targets, and personnel fatigue. Conclusion: The solution takes into account the simultaneous optimization of several criteria in order to select the most efficient way of performing preparatory shooting at serial number one in order to ensure rested and trained personnel as well as accurate and precise long range rifles for subsequent shootings, which leads to the maximum saving of resources, the satisfaction of personnel, and precise weapons. [ABSTRACT FROM AUTHOR]

The paper presents a developed model for measuring key performance indicators (KPI) of processes implemented in business organizations. The goal of the research is to identify problems that affect the processes through the measurement of KPIs, based on which the management of the organization improves its operations. The model was developed in four phases shown by the algorithm, based on higher-order fuzzy sets, more precisely, using Fermatean fuzzy sets (FFS). The first phase includes decomposing the process into sub-processes using the hierarchy-input-output-processing (HIPO) method and defining KPIs for measurements. In the second phase, the relative importance of sub-processes is determined using the Delphi method extended by FFS. In the third phase, KPIs are assessed at the level of each process by experts. In the fourth phase, KPIs are measured using the VIKOR (Multi-Criteria Optimization and Compromise Solution) method extended by FFS. The model was tested in a business organization that mainly deals with the maintenance of technical military systems. The obtained results confirmed the stability of the model by analyzing the comparison with the results of another method and by analyzing the sensitivity of the change of a certain parameter. The results have been verified in practice by the management of the business organization and, as such, serve for the constant improvement of business. [ABSTRACT FROM AUTHOR]

Introduction. Data on effects of thrombus aspiration on left ventricular diastolic function in ST-elevation myocardial infarction (STEMI) population are scarce. Objective. We sought to compare echocardiographic indices of the diastolic function and outcomes in STEMI patients treated with and without manual thrombus aspiration, in an academic, high-volume percutaneous coronary intervention (PCI) center. Methods. A total of 433 consecutive patients who underwent primary PCI in 2011-2012 were enrolled in the study. Patients were not eligible for the study if they already suffered a myocardial infarction, had been previously revascularized, received thrombolytics, presented with cardiogenic shock, had significant valvular disease, atrial fibrillation or had previously implanted pacemaker. Comprehensive echocardiogram was performed within 48 hours. During follow-up patients’ status was assessed by an office visit or telephone interview. Results. Patients treated with thrombus aspiration (TA+, n=216) had similar baseline characteristics as those without thrombus aspiration (TA-, n=217). Groups had similar total ischemic time (319 ± 276 vs. 333±372 min; p=0.665), but TA+ group had higher maximum values of troponin I (39.5 ± 30.5 vs. 27.6 ± 26.9 ng/ml; p15, as a marker of severe diastolic dysfunction (TA+ 23.1% vs. TA- 15.2%; p=0.050). During average follow-up of 14Ѓ}5 months, major adverse cardiac/ cerebral events occurred at the similar rate (log rank p=0.867). Conclusion. Thrombus aspiration is associated with a greater incidence of severe diastolic dysfunction in unselected STEMI patients treated with primary PCI, but it doesn’t influence the incidence of major adverse cardiovascular events. [Projekat Ministarstva nauke Republike Srbije, br. 175099]

Introduction. Spontaneous coronary artery dissection (SCAD) is a rare cause of the acute coronary syndrome. It occurs mostly in patients without atherosclerotic coronary artery disease, carrying fairly high early mortality rate. The treatment of choice (interventional, surgical, or medical) for this serious condition is not well-defined. Case report. A 41-year old woman was admitted to our hospital after the initial, unsuccessful thrombolytic treatment for anterior myocardial infarction administered in a local hospital without cardiac catheterization laboratory. Immediate coronary angiography showed spontaneous coronary dissection of the left main and left anterior descending coronary artery. Follow-up coronary angiography performed 5 days after, showed extension of the dissection into the circumflex artery. Because of preserved coronary blood flow (thrombolysis in myocardial infarction - TIMI II-III), and the absence of angina and heart failure symptoms, the patient was treated medicaly with dual antiplatelet therapy, a low molecular weight heparin, a beta-blocker, an angiotensinconverting enzyme (ACE) inhibitor and a statin. The patient was discharged after 12 days. On follow-up visits after 6 months and 2 years, the patient was asymptomatic, and coronary angiography showed the persistence of dissection with preserved coronary blood flow. Conclusion. Immediate coronary angiography is necessary to assess the coronary anatomy and extent of SCAD. In patients free of angina or heart failure symptoms, with preserved coronary artery blood flow, medical therapy is a viable option. Further evidence is needed to clarify optimal treatment strategy for this rare cause of acute coronary syndrome.

Background/Aim. The main complication of the atherosclerotic abdominal aortic aneurism (AAA) is her rupture that begins with lesion in intima and rupture. The purpose of this work was to determine immunocytochemical and morphofunctional characteristics of the cells in aortic wall in ruptured atherosclerotic abdominal aortic aneurysm. Method. During the course of this study, 20 samples of atherosclerotic AAA were analyzed, all of them obtained during authopsy. The samples were fixed in 4% formalin and embedded in paraffin. Sections of 5 μm thickness were stained histochemically (of Heidenhain azan stain and Periodic acid Schiff - PAS stain) and immunocytochemically using a DAKO LSAB+/HRP technique to identify α-smooth muscle actin (α-SMA), vimentin, myosin heavy chains (MHC), desmin, S-100 protein, CD45 and CD68 (DAKO specification). Results. The results of our study showed that ruptured atherosclerotic AAA is characterized by a complete absence of endothelial cells, the disruption of basal membrane and internal elastic lamina, as well as a presence of the remains of hypocellular complicated atherosclerotic lesion in intima. On the plaque margins, as well as in the media, smooth muscle cells (SMCs) are present, which express a α-SMA and vimentin (but without MHC or desmin expression), as well as leukocyte infiltration, and a large number of foam cells. Some of the foam cells show a CD68-immunoreactivity, while the others show vimentin- and S-100 protein-immunoreactivity. Media is thinned out with a disorganized elastic lamellas, while adventitia is characterized by inflammatory inflitrate (infection). Conclusion. Rupture of aneurysm occurs from the primary intimal disruption, which spreads into thinned out media and adventitia. Rupture is caused by unstable atherom, hypocellularity, loss of contractile characteristics of smooth muscle cells in intima and media, neovascularization of the media, as well as by the activity of the macrophages in the lesion.

Background/Aim. Graves disease (GD) is defined as hyperthyroidism with diffuse goiter caused by immunogenic disturbances. Antibodies to the thyroid stimulating hormone (TSH) receptors of thyroid gland (TRAb) have crucial pathogenetic importance in the development and maintenance of autoimmune hyperthyroidism. The aim of this study was to identify sensitivity, specificity, positive an negative predictive value of TRAb level in sera of patients with GD as well as to estimate significance of TRAb level for remission and GD relapses occurrence. Methods. We studied prospectively and partly retrospectively 149 patients, 109 female and 40 male patients, 5-78 years old, in the period 1982-2007. There were 96 patients with GD. The control group consisted of 53 patients, 21 with hyperthyroidism of second etiology and 32 patients on amiodarone therapy, with or without thyroid dysfunction TRAb was measured by radioreceptor assay (TRAK Assay and DYNO Test TRAK Human Brahms Diagnostica GMBH). Results. According to the results the sensitivity (Sn) of TRAb test was 80%, specificity (Sp) 100%, positive predictive value (PP) 100% and negative predictive value (NP) 83%. Also, the Sn of hTRAb test was 94%, Sp 100%, PP 100% and NP 94%. Our results show that an increased level of TRAb/hTRAb at the beginning of the disease and the level at the end of medical therapy is associated with an increased number of GD relapses and a shorter remission duration. Conclusion. Detection and measurement of TRAb in serum is a very sensitive method for diagnosing GD and very highly specific in vitro method for differential diagnosis of various forms of hyperthyroidism. Clinical significance of differentiating various forms of hyperthyroidism, using this in vitro assay, lays in adequate therapeutic choice for these entities.

One of the important and persistent problems that engineers face in the automotive industry is the reliability of production equipment. This research promotes a new fuzzy multicriteria model for determining the priority of failures in an exact manner. In this way, the decision makers can determine the management activities whose application should result in enhanced manufacturing process reliability, promptly. The analysis of failures is based on Failure mode and effects analysis that is extended with added risk factors, which represents the incremental improvement compared to the current literature sources. The relative importance of risk factors and their values are presented by pre‐defined linguistic expressions modelled by the interval type‐2 fuzzy numbers. The assessment of risk factors' relative importance is set as a fuzzy group decision‐making problem. The weights vector is determined by using the extended Best‐Worst Method. The rank of failures is obtained by employing the modified VIseKriterijumska Optimizacija i kompromisno Resenje (Eng. Multi‐criteria optimization and compromise solution) which reflects the scientific contribution of the research, and simultaneously, the second incremental improvement of the proposed model compared to the existing state of the art. These incremental improvements are: (i) The fuzzy algebra rules have been used for determining the group utility value and (ii) and individual regret value is determined by comparing the two interval type‐2 fuzzy numbers. The model testing and verification are performed on real data in an automotive supply chain. [ABSTRACT FROM AUTHOR]

The opportunity for large amounts of open-for-public and available data is one of the main drivers of the development of an information society at the beginning of the 21st century. In this sense, acquiring knowledge from these data using different methods of machine learning is a prerequisite for solving complex problems in many spheres of human activity, starting from medicine to education and the economy, including traffic as today's important economic branch. Having this in mind, this paper deals with the prediction of the risk of traffic incidents using both historical and real-time data for different atmospheric factors. The main goal is to construct an ensemble model based on the use of several machine learning algorithms which has better characteristics of prediction than any of those installed when individually applied. In global, a case-proposed model could be a multi-agent system, but in a considered case study, a two-agent system is used so that one agent solves the prediction task by learning from the historical data, and the other agent uses the real time data. The authors evaluated the obtained model based on a case study and data for the city of Niš from the Republic of Serbia and also described its implementation as a practical web citizen application. [ABSTRACT FROM AUTHOR]

Introduction. Persistent left superior vena cava represents a congenital vascular defect of the venous system, which often makes standard 58 cm endocardial lead placement impossible. Case Outline. A right chamber approach by the left cephalic vein was tried. This was impossible because standard endocardial lead (SJM Isoflex S 1646T, bipolar lead, 58 cm in length, body diameter 7 French) was too short for this patient. A unipolar lead for coronary sinus (Medtronic ATTEIN 4193-88), 88 cm in length, body diameter 4 French, was placed in the posterior branch of the coronary sinus. With such positioning of the lead, a VVI pacemaker pacing was enabled. The operation lasted for 48 minutes, and the time of total X-ray exposure was 9.6 minutes. The values that were achieved were: threshold 0.3 V, pulse width 0.37 ms, maximum R 22.55 mV. Ten months after the implantation, the values were: thresh- old 0.3 V, maximum R 28.8 mV. Conclusion. Persistent left superior vena cava in some cases makes standard 58 cm endocardial lead placement impossible due to its joining to the right atrium over the dilated coronary sinus. Coronary sinus lead placement in the posterior or lateral coronary sinus branch represents an acceptable alternative approach for pacemaker lead placement in these patients.