p-Adic and Adelic Free Relativistic Particle

We consider spectral problem for a free relativistic particle in p-adic and adelic quantum mechanics. In particular, we found p-adic and adelic eigenfunctions. Within adelic approach there exist quantum states that exhibit discrete structure of spacetime at the Planck scale.Comment: 9 page

Reality in Noncommutative Gravity

We study the problem of reality in the geometric formalism of the 4D noncommutative gravity using the known deformation of the diffeomorphism group induced by the twist operator with the constant deformation parameters \vt^{mn}. It is shown that real covariant derivatives can be constructed via $\star$-anticommutators of the real connection with the corresponding fields. The minimal noncommutative generalization of the real Riemann tensor contains only \vt^{mn}-corrections of the even degrees in comparison with the undeformed tensor. The gauge field $h_{mn}$ describes a gravitational field on the flat background. All geometric objects are constructed as the perturbation series using $\star$-polynomial decomposition in terms of $h_{mn}$. We consider the nonminimal tensor and scalar functions of $h_{mn}$ of the odd degrees in \vt^{mn} and remark that these pure noncommutative objects can be used in the noncommutative gravity.Comment: Latex file, 14 pages, corrected version to be publised in CQ

p-Adic and Adelic Harmonic Oscillator with Time-Dependent Frequency

The classical and quantum formalism for a p-adic and adelic harmonic oscillator with time-dependent frequency is developed, and general formulae for main theoretical quantities are obtained. In particular, the p-adic propagator is calculated, and the existence of a simple vacuum state as well as adelic quantum dynamics is shown. Space discreteness and p-adic quantum-mechanical phase are noted.Comment: 10 page

Wetting and drying numerical treatments for the Roe Riemann scheme

This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordAccurate characterization of wetting-drying fronts in free surface flows is challenging because it is difficult and computationally demanding to track the exact position of the interface. This work presents a novel numerical treatment of the wetting-drying fronts applied to an approximate Roe Riemann solver and compares it to four other approaches. The numerical treatments were implemented both for the shallow water equations and for the local inertial equations. The results of this comparison overall showed a good agreement. For the tests conducted it was verified that element removal numerical treatments with global distributing of water can introduce errors and degenerate the solution introducing or displacing water upstream. Local correction and flux restricting numerical treatments show the best results. The negative depth numerical treatments provided similar results to the local correction and flux restricting numerical treatment, although with mass conservation errors.This research was funded by the FCT (Fundação para a Ciência e a Tecnologia) through the doctoral grant [SFRH/BD/81869/2011] financed through the POPH/FSE (Programa Operacional Potencial Humano/Fundo Social Europeu) and the strategic project UID/MAR/04292/2013 granted by FCT to MARE

Uticaj dodavanja zeolita na kvalitet silaža sveže lucerke

The influence of natural zeolite addition on chemical composition and quality of silages was investigated. Lucerne was ensiled with and without technologically processed natural zeolite (Min-A-Zel, product of ITNMS Belgrade) in the amounts of 80, 400 and 2000 g per 100 kg of fresh lucerne (with approximately 250 g/kg dry matter). Ensiling was done immediately after harvesting or after 24 hours (two factorial experiment 4 x 2). Second part of the experiment (alter 24 hours) was done to investigate the additional contamination of lucerne with aerial microorganisms. The results of the investigations show that addition of the technologically processed natural zeolite while lucerne ensiling enhances the fermentation intensity and results in the increase in acetic acid production with the lower pH values and more favorable ratio of lactic to total acids. The influence of mentioned doses of zeolite on chemical composition was less pronounced and is mostly relative. The only real changes were the increase of dry matter content and of the mineral content. According to DLG method the control silage was ranked as III quality class, silages with lowest and medium doses of zeolite in II quality class and silage with maximal dose of zeolite in 1 quality class.U ogledu je ispitivan uticaj dodavanja prirodnog zeolita na hemijski sastav i kvalitet silaža lucerke. Lucerka je silirana bez i sa dodatkom tehnološki obrađenog prirodnog zeolita (pod nazivom Min-A-Zel, proizvod ITNMS -Beograd) u količini od 80, 400 i 2000 g na 100 kg sveže lucerke (sa oko 250 g/kg suve materije). Siliranje lucerke je obavljeno odmah po košenju i posle 24 sata (dvofaktorijalni eksperiment, 4 x 2). Drugi deo eksperimenta (posle 24 sata) izveden je u cilju dodatne kontaminacije lucerke mikroorganizmima iz vazduha. Rezultati obavljenih istraživanja pokazuju da dodavanje tehnološki obrađenog prirodnog zeolita pri siliranju lucerke doprinosi intenziviranju fermentacije i povećanju produkcije mlečne kiseline, uz postizanje nižih pH vrednosti i povoljnijeg odnosa mlečne prema ukupnim kiselinama. Uticaj navedenih doza zeolita na standardni hemijski sastav je bio manji, i pretežno je relativnog karaktera. Jedine realne promene su povećanje stepena suve materije i povećanje količine mineralnog ostatka. Prema DLG metodi kontrolna silaža je svrstana u III klasu kvaliteta, silaže sa nižom i srednjom dozom zeolita u II klasu, a silaža sa maksimalnom dozom zeolita u I klasu kvaliteta

Experimental calibration and validation of sewer/surface flow exchange equations in steady and unsteady flow conditions

This is the final version of the article. Available from Elsevier via the DOI in this record.The linkage between sewer pipe flow and floodplain flow is recognised to induce an important source of uncertainty within two-dimensional (2D) urban flood models. This uncertainty is often attributed to the use of empirical hydraulic formulae (the one-dimensional (1D) weir and orifice steady flow equations) to achieve data-connectivity at the linking interface, which require the determination of discharge coefficients. Because of the paucity of high resolution localised data for this type of flows, the current understanding and quantification of a suitable range for those discharge coefficients is somewhat lacking. To fulfil this gap, this work presents the results acquired from an instrumented physical model designed to study the interaction between a pipe network flow and a floodplain flow. The full range of sewer-to-surface and surface-to-sewer flow conditions at the exchange zone are experimentally analysed in both steady and unsteady flow regimes. Steady state measured discharges are first analysed considering the relationship between the energy heads from the sewer flow and the floodplain flow; these results show that existing weir and orifice formulae are valid for describing the flow exchange for the present physical model, and yield new calibrated discharge coefficients for each of the flow conditions. The measured exchange discharges are also integrated (as a source term) within a 2D numerical flood model (a finite volume solver to the 2D Shallow Water Equations (SWE)), which is shown to reproduce the observed coefficients. This calibrated numerical model is then used to simulate a series of unsteady flow tests reproduced within the experimental facility. Results show that the numerical model overestimated the values of mean surcharge flow rate. This suggests the occurrence of additional head losses in unsteady conditions which are not currently accounted for within flood models calibrated in steady flow conditions.The research has been supported by the UK Engineering and Physical Sciences Research Council (grants ID: EP/K040405/1)

Agriotypus armatus Curtis, 1832, a parasitoid of Silo pallipes Fabricius, 1781: the first record for the Balkan Peninsula

Among the diverse order of Hymenoptera, aquatic species are of special interest. During macrozoobenthos sampling in the rivers of Serbia in 2003 and during the period 2011-2012, pupae of Silo pallipes Fabricius, 1781 were recorded which were parasitized by an ichneumonid wasp Agriotypus armatus Curtis, 1832, this being the first record of it for the Balkan Peninsula. A total of 217 A. armatus specimens were collected at 29 localities situated along 16 watercourses of Serbia. All four parasitoid stages (egg, larva, pupa and resting adult) were recorded. The identity of the parasitoid was confirmed using standard molecular methods. This study also focuses on the ecology of the parasitoid and its host. The widespread distribution of A. armatus in Europe suggests the presence of this species in other Balkan countries, but this has not yet been confirmed due to a lack of surveys and/or the constantly increasing pollution of freshwaters

Raspodela pristupačnih sadržaja mikroelemenata po dubini kultivisanog zemljišta

This paper presents a study of the profile distribution of available micronutrients Fe, Mn, Cu and Zn and radionuclide 137Cs in cultivated soil at the experimental field 'Radmilovac' (property of Agricultural Faculty, Belgrade University) in the vicinity of Vinča Institute of Nuclear Sciences. The soil belongs to the anthrosol class of anthropogenic soils according to FAO (2006). At first, the deep plowing was performed while preparing soil for planting peach trees followed by cultivation of soil for 12 years. All agricultural treatments at the experimental field ceased for three years. After that period, soil sampling was carried out. Contents of DTPA-extracted Fe, Mn, Cu and Zn were in the range of (mg kg-1): 5.8-41.6; 9.2-34.2; 1-7.6 and 0.2-1.3, respectively. Detected activity concentration (Bq kg-1) for 137Cs ranged from 1.8 to 35. It was noticed that distribution patterns of 137Cs radionuclide and available Cu and Zn along soil depth were very similar and they were analyzed by simple linear regression; mutual affinity for the soil organic matter might affect their distribution in soil. Contents of available Fe and Mn exhibited different, more constant distribution within a soil horizon.U ovom radu ispitivana je raspodela sadržaja pristupačnih mikroelemenata Fe, Mn, Cu i Zn i koncentracije aktivnosti proizvedenog radionuklida 137Cs u profilima zemljišta (dubine 080 cm) sakupljenih sa voćnjaka pod zasadom breskvi na oglednom školskom poljoprivrednom dobru 'Radmilovac' (Poljoprivredni fakultet, Univerzitet u Beogradu) u neposrednoj blizini Instituta za nuklearne nauke 'Vinča'. Zemljište pripada klasi antrosol antropogenih zemljišta prema međunarodnoj FAO (2006) klasifikaciji. Priprema zemljišta za sadnju bresaka izvršena je rigolovanjem, posle čega je usledila 12 godina duga nega voćnjaka. Uzorkovanje zemljišta izvršeno je tri godine nakon prestanka svih poljoprivrednih tretmana zemljišta na oglednom polju. Sadržaji pristupačnih mikroelemenata Fe, Mn, Cu i Zn (dobijeni ekstrakcijom sa rastvorom 0,005 M DTPA) nalazili su se u opsegu (mg kg-1): 5,841,6; 9,234,2; 17,6 odnosno 0,21,3. Detektovana koncentracija aktivnosti 137Cs u zemljištu (merena metodom gama-spektrometrije korišćenjem koaksijalnog HPGe-detektora) nalazila se u intervalu (Bq kg-1): 1,835. Uočeno je da su obrasci distribucije po dubini profila pristupačnih oblika Cu i Zn i radionuklida 137Cs bili veoma slični, a rezultati proste linearne regresione analize su pokazali da je uzajamni afinitet prema organskoj materiji zemljišta mogao da utiče na takvu njihovu distribuciju. Sadržaji pristupačnih mikroelemenata Fe i Mn, pokazali su da imaju drugačiju, uniformniju distribuciju po dubini ispitivanih profila zemljišta

Report and papers with guidelines on calibration of urban flood models

Computer modelling offers a sound scientific framework for well-structured analysis and management of urban drainage systems and flooding. Computer models are tools that are expected to simulate the behaviour of the modelled real system with a reasonable level of accuracy. Assurance of accurate representation of reality by a model is obtained through the model calibration. Model calibration is an essential step in modelling. This report present concepts and procedures for calibration and verification of urban flood models. The various stages in the calibration process are presented sequentially. For each stage, a discussion of general concepts is followed by descriptions of process elements. Finally, examples and experiences regarding application of the procedures in the CORFU Barcelona Case Study are presented. Calibration involves not only the adjustment of model parameters but also other activities such as model structural and functional validation, data checking and preparation, sensitivity analysis and model verification, that support and fortify the calibration process as a whole. The objective in calibration is the minimization of differences between model simulated results and observed measurements. This is normally achieved through a manual iterative parameter adjustment process but automatic calibration routines are also available, and combination parameter adjustment methods also exist. The focus of a model calibration exercise is not the same for all types of models. But regardless of the model type, good modelling practice should involve thorough model verification before application. A well-calibrated model can give the assurance that, at least for a range of tested conditions, the model behaves like the real system, and that the model is an accurate and reliable tool that may be used for further analysis. However, calibration could also reveal that the model cannot be calibrated and that the correctness of the model and its suitability as a tool for analysis and management of real-world systems could not be proven. The conceptualisation and simplification of real-world systems and associated processes in modelling inevitably lead to errors and uncertainty. Various modelling components introduce errors such as the input parameters, the model concept, scheme and corresponding model output, and the observed response measurements. Ultimately, the quality of the model as quantified by how much it deviates from reality is an aggregate of the errors that have been brought into it during the modelling process. Thus, it is important to identify the different error sources in a model and also account for and quantify them as part of the modelling.The work described in this publication was supported by the European Community’s Seventh Framework Programme through the grant to the budget of CORFU Collaborative Research on Flood Resilience in Urban Areas, Contract 244047

Trendovi u siliranju leguminoza

Modern trends in legumes ensilaging technology are based on the knowledge of biomass from the aspect of suitability for ensilaging, wilting, addition of carbohydrate feed, use of biological additives, etc. Today, the experiments are conducted, worldwide, with inoculates, which, in addition to homofermentative, also contain heterofermentative lactic acid bacteria. Products of such inoculants contribute to the increase of aerobic stability of silages so their implementation is good for all types of silage. In addition to the usage of those additions, modern technology of silage is based on the maximum mechanization of the ensilaging process, as well as preparing the silage in the form of roto-bales and silo tubes (most inexpensive way of conservation) as well as permanent facilities.Savremeni trendovi u tehnologiji siliranja leguminoza zasnivaju se na poznavanju biomasa sa aspekta pogodnosti za siliranje, provenjavanju, dodavanju ugljenohidratnih hraniva, upotrebi bioloških dodataka, i dr. Trenutno se u svetu eksperimentiše sa inokulantima, koji pored homofermentativnih, sadrže i heterofermentativne bakterije mlečne kiseline. Produkti ovakvih inokulanata doprinose povećanju aerobne stabilnosti silaža, pa su navedeni dodaci aktuelni za sve vrste silaža. Osim korišćenja navedenih dodataka, savremena tehnologija siliranja se bazira na maksimalnoj mehanizovanosti celokupnog procesa siliranja, kao i pripremanja silaže u formi roto-bala i silokobasica (najeftiniji vid konzervisanja) kao i stalnih objekata