30 research outputs found
The influence of product complexity on team performance within NPD
This paper explores the influence of product complexity on team performance. A longitudinal case study of a Masters course European Global Product Realisation, where 4 universities collaborate on product development projects is used to study the phenomenon. 4 different projects are explored, where in 2 of them teams worked on the full product development process for a particular product and 2 projects where several teams worked on a single product, thus the focus was on developing specific modules of the same product, due to its complexity
Arsenic removal from water using low-cost adsorbents: A comparative study
Inorganic arsenic removal from water using low-cost adsorbents is presented in this paper. Selective removal of As(III) and As(V) from water was performed with natural materials (zeolite, bentonite, sepiolite, pyrolusite and limonite) and industrial by-products (waste filter sand as a water treatment residual and blast furnace slag from steel production); all inexpensive and locally available. Kinetic and equilibrium studies were realized using batch system techniques under conditions that are likely to occur in real water treatment systems. The natural zeolite and the industrial by-products were found to be good and inexpensive sorbents for arsenic while bentonite and sepiolite clays showed little affinity towards arsenic. The highest maximum sorption capacities were obtained for natural zeolite, 4.07 mg As(V) g-1, and waste iron slag, 4.04 mg As(V) g-1
Erratum: Systematic uncertainties in integrated luminosity measurement at CEPC (Journal of Instrumentation (2022) 17 (P09014) DOI: 10.1088/1748-0221/17/09/P09014)
The very forward region is one of the most challenging regions to instrument at a future + − collider. At CEPC, machine-detector interface includes, among others, a calorimeter dedicated for precision measurement of the integrated luminosity at a per mill level or better. Here we review a feasibility of such precision, from the point of view of systematic effects arising from luminometer mechanical precision and positioning, beam-related requirements and physics background from two-photon processes. The impact of the beam energy spread and its uncertainty on the integrated luminosity precision is also discussed, as well as the achievable beam energy spread precision with the post-CDR CEPC beamsLink to the corrected article: [https://vinar.vin.bg.ac.rs/handle/123456789/10567
Influence of soil properties on soil-to-plant transfer factors of natural radionuclides in the vicinity of coal fired power plants in Serbia
Study of coal fired power plants environmental impact have been performed analyzing activity concentrations of natural radionuclides 238U, 226Ra, 232Th and 40K in the samples of soil and native vegetation collected in the vicinity of TE “Kolubara”, TE “Morava” and TE “Nikola Tesla” A and B power plants. Soil-to-grass transfer factor values (kg kg-1 dry mass) were calculated. Some soil characteristics such as particle size distribution, soil pH, organic matter content and carbonate content were determined in order to examine their influence on natural radionuclides soil-to-plant transfer factors, assuming TFs are mostly controlled by root uptake
Emergency or delayed surgical treatment of unstable supracondylar humeral fractures in children?
© 2017, University of Kragujevac, Faculty of Science. All rights reserved. Supracondylar humeral fractures (SCHF) are the most common elbow fractures in children, representing 3% of all paediatric fractures. Treatment options for SCHF in children are based on the Gartland classification. Treatment of non-displaced fractures (type I) is non-operative. Plaster immobilization for 3 to 4 weeks is recommended, depending on the age of the child and fracture healing. Treatments of displaced supracondylar fractures (type II and III) of the humerus in children are still undefined in clinical practice. Because of divided opinions, the aim of this study was to evaluate whether delayed or immediate surgical treatment has an advantage in the treatment of supracondylar fractures in children. This is a prospective – retrospective clinical study. This study included 64 patients from 5 to 15 years old; 47 (73.4%) were boys and 17 (26.6%) were girls. The most common age range (59.4%) in this study was 5-8 years old. All patients were diagnosed with supracondylar fractures at the Institute for Orthopaedic Surgery “Banjica”. We analysed 17 parameters, which were obtained either from direct patient interviews or from their medical history. All patients were divided into two groups with matched characteristics. Group I consisted of 26 patients who had immediate operations. Group II consisted of 38 patients who had delayed operations. Based on the results of the analysed parameters, consisting primarily of functional results, the absence of subjective symptoms and myositis ossificans one year after surgery suggests that emergency surgical treatment of displaced supracondylar humeral fractures is optimal
Systematic uncertainties from mechanics and MDI in luminosity measurement at CEPC
The very forward region is one of the most challenging regions to instrument
at a future collider. At CEPC, machine-detector interface include,
among others, a calorimeter dedicated for precision measurement of the
integrated luminosity at a permille level or better. Here we review a
feasibility of such precision, from the point of view of luminometer mechanical
precision and positioning, beam-related requirements and physics background.A
method of the effective center-of-mass determination due to the beam-spread,
initially proposed for FCC, is also discussed for the CEPC beams
Improving the efficiency of using heat in preschool buildings: Case study of 'Ciciban' kindergarten
Educational buildings have a significant share in the total number of buildings of public sector. Also, significant part of energy consumption belongs to these buildings. There are 15 kindergartens that are under 2 preschool institutions. Their specific annual heat consumptions are from 79.42 kWh/m2 to 491.52 kWh/m2 (from 106.02 kWh/m2 to 325 kWh/m2 for objects connected to the district heating system). The average specific annual heat consumption is about 22% more than the consumption in neighboring countries. Most kindergarten buildings were built in the '70 and '80s of the last century and do not have adequate thermal insulation. Based on the defined methodology, specific annual heat consumption of these buildings has been analyzed, priorities for reconstruction have been defined and measures for improvement of energy efficiency have been proposed. Conducted case study of implementing the proposed measures at 'Ciciban' kindergarten showed that savings could be from 36% to 58% in heat consumption
Measurement of the H to ZZ branching fraction at a 350 GeV and 3 TeV CLIC
In this paper we investigate the prospects for measuring the branching fraction of the Standard Model Higgs boson decay into a pair of Z bosons at the future Compact Linear Collider (CLIC) at 350 GeV and 3 TeV center-of-mass energies. Studies are performed using a detailed simulation of the detector for CLIC, taking into consideration all relevant physics and beam-induced background processes. It is shown that the product of the Higgs production cross section and the branching fraction BR(H→ZZ*) can be measured with a relative statistical uncertainty of 20% (3.0%) at a center-of-mass energy of 350 GeV (3 TeV) using semileptonic final states, assuming an integrated luminosity of 1 ab-1 (5 ab-1).In this paper we investigate the prospects for measuring the branching fraction of the Standard Model Higgs boson decay into a pair of bosons at the future Compact Linear Collider (CLIC) at 350 GeV and 3 TeV centre-of-mass energies. Studies are performed using a detailed simulation of the detector for CLIC, taking into consideration all relevant physics and beam-induced background processes. It is shown that the product of the Higgs production cross-section and the branching fraction BR() can be measured with a relative statistical uncertainty of 20% (3.0%) at a centre-of-mass energy of 350 GeV (3 TeV) using semileptonic final states, assuming an integrated luminosity of 1 ab (5 ab)
Impact of Mineral Composition on the Distribution of Natural Radionuclides in Rigosol-Anthrosol
Primordial radionuclides present in the rocks and minerals of the earth's crust are naturally occurring source of radiation that has important impact on human health. Therefore, it is essential to evaluate origin, mobility and transfer of natural radionuclides in ecosystem.
Our paper represents the results of influence of mineral composition, sand-, silt-, and clay- size mechanical fraction and heavy mineral fraction on distribution and mobility of natural radionuclides 238U, 232Th, 226Ra and 40K in profiles of soil type rigosol, from the area of school estate good ”Radmilovac” of Faculty of Agriculture, Zemun, University of Belgrade.
Methods used were X-ray powder diffraction, heavy liquid mineral separation, HCBr3, scanning electron microscopy (SEM) and gamma-ray spectrometry. Analysis of the results showed correlation of natural radionuclides with heavy mineral fraction (Fe oxides and hydroxides, epidote, ilmenite-rutile, staurolite and zircon, garnet, amphibole) and secondary minerals (Ca montmorillonite, mix layer silicates (MSS), illite, kaolinite and vermiculite)
Changes in maximal oxygen uptake during growth and development in girls who actively participate in basketball and non-athletes girls: A longitudinal study
© 2018, Inst. Sci. inf., Univ. Defence in Belgrade. All rights reserved. Background/Aim. It is well known that continuous engagement in physical activity is important for normal growth and development of children. Maximal oxygen uptake (VO2max), as a measure of functional state of the organism, is largely affected by level of physical activity, but it remains unclear to what extent it can be improved during childhood. The aim of the study was to evaluate dynamics of changes in aerobic capacity, anthropometric and body composition characteristics in active and non-active girls over a period of 3 years. Methods. A total of 48 young girls were included in the study. Girls were divided into 2 groups: training group consisted of 25 girls who played basketball (age 13.84 ± 0.94) and non-training group of 23 girls who were not involved in any organized sports (age 13.83 ± 0.98). Anthropometric and body composition characteristics were measured in order to monitor somatic growth during the study. VO2maxvalues were obtained by performing cardiopulmonary exercise testing on a treadmill. All parameters were measured every 6 months during 3-years period. Results. ANOVA analysis showed a significant time and group interaction effect on VO2max (p < 0.001), body mass index (BMI) (p < 0.001) and fat percentage (FAT%) (p < 0.01). Also, there was an obvious increase in VO2max within both groups due to growth and development itself (p < 0.001). Conclusion. The main finding of the study was an increase in VO2max due to growth and development. The girls who actively participated in basketball had higher level of aerobic capacity compared to non-active girls. Furthermore, continuous basketball training led to maintaining normal body composition in terms of FAT% and BMI, which altogether may imply that organized physical activity has a positive influence on evaluated characteristics