101 research outputs found

    Design of novel tilting electric four-wheelers

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    EU cities are increasingly congested due to the demand and usage of motor vehicles. Future scenarios for EU urban centers see a modal shift in personal mobility from cars to lighter, smaller, more specialized and environmental-friendly alternatives. Electric L-category Vehicles (ELVs) are viable alternatives that can fulfill the commuter needs due to their small size and light-weight: by consequence the energy requirement, battery size and related costs can be strongly reduced respect to conventional electric cars. However, this modal shift must overcome one main challenge: most car drivers do not consider Lcategory vehicles as a suitable option mainly due to L-vehicle dynamic limitations. To achieve that, the RESOLVE (Range of Electric SOlutions for L-category VEhicles) project, funded in the Horizon 2020 framework - Green Vehicles GV5-2014 call, will develop components and systems aimed to meet the low cost target required for this segment. At the same time, the project will deliver an exciting and attractive ELV driving experience by proposing new concepts (tilting and narrow track), while containing as much as possible the vehicle energy consumption. In this paper, the dynamics analyses carried out to develop the architecture of ELV vehicles are presented. A stability analysis of the vehicles in straight line was firstly carried out and the results were compared to tilting two and three-wheelers for a wide range of speed. A detailed multibody model was developed to simulate the steady-state behavior of the 4-wheelers during turning and to perform further dynamic analyses. In addition, an entire vehicle model including electrical and mechanical components (battery, power electronics, e-motor, driveline, etc.) was developed to assess the ELVs energy needs during reference and real-world driving maneuver. The results demonstrated the feasibility of this novel kind of vehicles, confirming the exciting driving experience typical of tilting vehicles, combined with comfort, low environmental impact and limited energy requirements

    A NOVEL DISCRETE RAT SWARM OPTIMIZATION ALGORITHM FOR THE QUADRATIC ASSIGNMENT PROBLEM

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    The quadratic assignment problem (QAP) is an NP-hard problem with a wide range of applications in many real-world applications. This study introduces a discrete rat swarm optimizer (DRSO)algorithm for the first time as a solution to the QAP and demonstrates its effectiveness in terms of solution quality and computational efficiency. To address the combinatorial nature of the QAP, a mapping strategy is introduced to convert real values into discrete values, and mathematical operators are redefined to make then suitable for combinatorial problems. Additionally, a solution quality improvement strategy based on local search heuristics such as 2-opt and 3-opt is proposed. Simulations with test instances from the QAPLIB test library validate the effectiveness of the DRSO algorithm, and statistical analysis using the Wilcoxon parametric test confirms its performance. Comparative analysis with other algorithms demonstrates the superior performance of DRSO in terms of solution quality, convergence speed, and deviation from the best-known values, making it a promising approach for solving the QAP

    Characterization of bread wheat cultivars (Triticum aestivum L.) by glutenin proteins

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    Glutenin polymers composed of HMW and LMW subunits are important contributors to the wheat end-use properties. Twenty-six winter wheat cultivars differing in bread processing quality were collected at the experimental fields of the Agricultural Institute Osijek, Croatia and Institute of the Field and Vegetable Crops Novi Sad, Serbia, in 2008/2009 season. The HMW glutenins composition and glutenin proteins content were determined by SDS-PAGE and RP-HPLC, respectively, with aim to determine the relationship between glutenin protein fractions and wheat quality properties. Significant differences were found between Croatian and Serbian cultivars in several quality attributes (GI, WA, DDT, DS and R/EXT) as well as in the content of total glutenins and LMW glutenins and GLI/GLU ratio. The dominant HMW subunits in analyzed cultivars were 2*, 7 + 9/7 + 8 and 5 + 10. Principal component analysis (PCA) confirmed the presence of association between HMW glutenins composition and GI, dough E, R and R/EXT, while the glutenins quantitative data showed pronounced relation with P, DDT, DS, E, R and R/EXT. GLI/GLU ratio had the opposite effect on these parameters

    HYBRID GENETIC AND PENGUIN SEARCH OPTIMIZATION ALGORITHM (GA-PSEOA) FOR EFFICIENT FLOW SHOP SCHEDULING SOLUTIONS

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    This paper presents a novel hybrid approach, fusing genetic algorithms (GA) and penguin search optimization (PSeOA), to address the flow shop scheduling problem (FSSP). GA utilizes selection, crossover, and mutation inspired by natural selection, while PSeOA emulates penguin foraging behavior for efficient exploration. The approach integrates GA's genetic diversity and solution space exploration with PSeOA's rapid convergence, further improved with FSSP-specific modifications. Extensive experiments validate its efficacy, outperforming pure GA, PSeOA, and other metaheuristics

    Reintrodukcija i repopulacija linjaka (Tinca Tinca l.) u ribnjačke sisteme i otvorene vode

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    Tench (family Cyprinidae) is widespread in Europe and is one of the economically significant fish species of the region. It is most commonly bred as supplemental fish in pond polyculture with carp. Recently, its presence in our fish pond systems and natural waters has almost disappeared due to replacement with other fish species. There is necessity of tench reintroduction in aquaculture of Serbia, because its certain positive features. In order to perform tench repopulation in an adequate way it is necessary to master with controlled spawning in our equipment and practitioner hatcheries. Ambient conditions need adapt considering literature data and knowledge in technological processes of the carp production. Should tend to balancing use of the habitant nature capacities from our surrounding and production where no added chemical compounds to make tench production in our conditions organic, ecologically safe

    ZNAČAJ PRAVILNE ISHRANE KRMNIH LEGUMINOZA FOSFOROM NA KISELIM ZEMLJIŠTIMA

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    In the Republic of Serbia, acid soils cover about 60% of the total arable land. On such soils, numerious micro and macro elements are hardly accessible for plants. Sufficient supply of leguminous plants with phosphorus is very important for the processes of their growth and development, nodulation and nitrogen fixation. The aim of this study was to analyze the importance of proper nutrition of leguminous plants with phosphorus on acid soils and to point out the problems that exist in such conditions, as well as the possible ways to solve them

    Contamination, risk, and source apportionment of potentially toxic microelements in river sediments and soil after extreme flooding in the Kolubara River catchment in Western Serbia

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    Climate change is contributing to an increase in extreme weather events. This results in a higher river flooding risk, causing a series of environmental disturbances, including potential contamination of agricultural soil. In Serbia, the catastrophic floods of 2014 affected six river basins, including the Kolubara River Basin, as one of the larger sub-catchments of the large regional Sava River Basin, which is characterized by large areas under agricultural cultures, various geological substrates, and different types of industrial pollution. The main aim of this study was to establish the sources of potentially toxic elements in soil and flood sediments and the effect of the flood on their concentrations. Field sampling was performed immediately after water had receded from the flooded area in May 2014. In total, 36 soil samples and 28 flood sediment samples were collected. After acid digestion (HNO3), concentrations of the most frequent potentially toxic elements (PTE) in agricultural production (As, Cd, Cr, Cu, Ni, Pb, Zn) and Co which are closely related to the geological characteristics of river catchments, were analyzed. The origin, source, and interrelations of microelements, as well as BACKGROUND: values of the PTE of the river catchment, the pollution index (Pi), enrichment factor (Ef), and geological index (Igeo), were determined, using statistical methods such as Pearson correlations, principal component analysis (PCA), and multiple linear regression (MLRA). The content of the hot acid-extractable forms of the elements, PCA, and MLRA revealed a heavy geological influence on microelement content, especially on Ni, Cr, and Co, while an anthropogenic influence was observed for Cu, Zn, and Cd content. This mixed impact was primarily related to mines and their impact on As and Pb content. The pseudo-total concentrations of all the analyzed elements did not prove to be a danger in the catchment area, except for Cu in some samples, indicating point-source pollution, and Ni, whose pseudo-total content could be a limiting factor in agricultural production. For the Ef, the Ni content in 59% soil and 68% flood sediment samples is classified into influence classes. The similar pseudo-total contents of the elements studied in soil samples and flood sediment and their origin indicate that the long-term soil formation process is subject to periodic flooding in the Kolubara River Basin without any significant changes taking place. This implies that floods are not an endangering factor in terms of the contamination of soil by potentially toxic elements in the explored area

    Left ventricular function, congestion, and effect of empagliflozin on heart failure risk after myocardial infarction

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    Background Empagliflozin reduces the risk of heart failure (HF) hospitalizations but not all-cause mortality when started within 14 days of acute myocardial infarction (AMI). Objective To evaluate the association between left ventricular ejection fraction (LVEF), congestion, or both on outcomes and the impact of empagliflozin in reducing HF risk post-MI. Methods In the EMPACT-MI trial, patients were randomized within 14 days of an AMI complicated by either newly reduced LVEF<45%, congestion, or both to empagliflozin 10 mg daily or placebo and followed for a median of 17.9 months. Results Among 6522 patients, the mean baseline LVEF was 41%+9%; 2648 patients (40.6%) presented with LVEF<45% alone, 1483 (22.7%) presented with congestion alone, and 2181 (33.4%) presented with both. Among patients in the placebo arm, multivariable adjusted risk for each 10-point reduction in LVEF included all-cause death or HF hospitalization (hazard ratio [HR] 1.49; 95%CI, 1.31-1.69; P<0.0001), first HF hospitalization (HR, 1.64; 95%CI, 1.37-1.96; P<0.0001), and total HF hospitalizations (rate ratio [RR], 1.89; 95%CI, 1.51-2.36; P<0.0001). Presence of congestion was also associated with a significantly higher risk for each of these outcomes (HR 1.52, 1.94, and RR 2.03, respectively). Empagliflozin reduced the risk for first (HR 0.77, 95%CI 0.60-0.98) and total (RR 0.67, 95%CI 0.50-0.89) HF hospitalization, irrespective of LVEF or congestion or both. The safety profile of empagliflozin was consistent across baseline LVEF and irrespective of congestion status. Conclusions In patients with AMI, severity of LV dysfunction and the presence of congestion was associated with worse outcomes. Empagliflozin reduced first and total HF hospitalizations across the range of LVEF with and without congestion

    Effect of empagliflozin on heart failure outcomes after acute myocardial infarction: insights from the EMPACT-MI trial

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    Background: Empagliflozin reduces the risk of heart failure events in patients with type 2 diabetes at high cardiovascular risk, chronic kidney disease, and in those with prevalent heart failure irrespective of ejection fraction. While EMPACT-MI showed empagliflozin does not reduce the risk of the composite of hospitalization of heart failure and all-cause mortality, the impact of empagliflozin on first and recurrent heart failure events in patients after myocardial infarction is unknown. Methods: EMPACT-MI was a double-blind, randomized, placebo-controlled, event-driven trial that randomized 6522 patients hospitalized for acute myocardial infarction at risk for heart failure based on newly developed left ventricular ejection fraction of <45% and/or signs or symptoms of congestion to receive empagliflozin 10 mg daily or placebo within 14 days of admission. In prespecified secondary analyses, treatment groups were analyzed for heart failure outcomes. Results: Over a median of follow-up of 17.9 months, the risk for first heart failure hospitalization and total heart failure hospitalizations was significantly lower in the empagliflozin compared with the placebo group (118 (3.6%) vs. 153 (4.7%) patients with events, HR 0.77 [95% CI 0.60, 0.98], P=0.031 for first heart failure hospitalization and 148 vs. 207 events, RR 0.67 [95% CI 0.51, 0.89], P=0.006 for total heart failure hospitalizations). Subgroup analysis showed consistency of empagliflozin benefit across clinically relevant patient subgroups for first and total heart failure hospitalizations. Post-discharge need for new use of diuretics, renin-angiotensin modulators, and mineralocorticoid receptor antagonists were less in patients randomized to empagliflozin than placebo (all p<0.05). Conclusions: In patients after acute myocardial infarction with left ventricular dysfunction or congestion, empagliflozin reduced the risk of heart failure
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