Taksonomija ucnih metod in oblik za mlade v neformalnem izobrazevanju v Mladinskem svetu Slovenije

Research from the field of non-formal education (NFE) in youth work emphasises the central role of experiential learning and learning in groups. The present paper aims to research teaching methods and teaching forms in NFE in youth work. The research sought to answer the following research questions: ‘What teaching forms can be found in NFE for young people in youth councils on a national level in Slovenia?’ and ‘What teaching methods can be found in NFE for young people in youth councils on a national level in Slovenia?’ Data was collected using semi-structured interviews; the instrument was a list of questions. The empirical research was conducted in July 2016 with six interviewees. The results indicate that learning in selected NFE in the National Youth Council of Slovenia (MSS) is participatory, interactive, inclusive and student-focused; with central concepts of experiential learning and learning in groups. The key teaching form is learning in groups. However, individual work, work in pairs, programmed instruction and direct instruction are also present. The central and omnipresent teaching method is experiential learning. Problem-based learning, case-study method, action learning, and project-based learning are intertwined and connected to the experiential learning method. Other methods include verbal-textual methods, illustrative-demonstration methods, experimental methods, peer learning, and support methods. The conclusions are applicative in the didactic spectrum of NFE in youth work and in the wider didactic spectrum of adult learning. Implications for further research include teaching methods and forms in NFE inside the wider youth sector, internationally comparative and through quantitative research. (DIPF/Orig.

Flattened Galactic Haloes and Baryonic Dark Matter

We discuss the tight interconnection between microlensing optical depths, flattening of dark haloes and low-to-intermediate redshift baryonic census. By analysing plots of the microlensing optical depth as a function of galactic coordinates for different values of axis ratio $q$ of the galactic MACHO halo, we have shown that observations are best described by a flattened halo with $q \simeq 0.6$. There is no dynamical obstacle for such a choice of global halo shape. Both extremely flattened $q \simeq 0.2$ and spherical $q \simeq 1$ haloes have several difficulties, although not of equal severity. Consequences of such flattening for the cosmological density fraction contained in MACHOs are considered and comparison with mass in low and intermediate-redshift Ly$\alpha$ forest and other plausible reservoirs of gas is discussed in context of a unified description of the evolution of baryonic content of the universe.Comment: 14 pages, 15 figures, TeX, uses mn.tex and psfig.tex, MNRAS accepte

Synthesis of Cerium-Activated Yttrium Aluminate Based Fine Phosphors by an Aerosol Route

Polycrystalline fine powders of yttrium aluminate doped with Ce³⁺ were synthesised by spray pyrolysis of a polymeric pre-cursor, which was obtained by dissolving the corresponding nitrates in a solution of ethylenediaminetetraacetic acid (EDTA) in ethylene glycol (EG). Aerosol decomposition was performed at 550 °C followed by an additional thermal treat-ment (900–1100 °C). The yield of either a single yttrium alu-minium perovskite (YAP) phase or a single yttrium alumin-ium garnet (YAG) phase was investigated as a function of the predefined yttrium/aluminium ratio, the cerium doping concentration, the processing temperature, and the thermal-treatment regime, which included the variation of the heat-ing and cooling rates (dT/dt), the residence time (τ), and the atmosphere. Changes in the composition and structure of the precursor during thermal decomposition were investigated by thermogravimetric and differential thermal analysis (TGA/DTA) and FTIR spectroscopy. The particle morphology and structure were analysed by a combination of scanning electron microscopy and energy-dispersive X-ray spec-troscopy (SEM/EDS) and by highresolution transmission electron microscopy (HR-TEM). The structural refinement was based on the phase identification performed by X-ray powder diffraction (XRPD). The emission spectra were re-corded within the range 325–800 nm by applying excitation wavelengths of 297 (YAP) and 450 nm (YAG). The employed synthesis conditions assured the formation of spherical, non-agglomerated particles with well-developed surfaces and diameters between 200 and 800 nm. For a predefined Y/Al ratio of 1:1, lower processing temperatures combined with longer heat treatments under stationary conditions resulted in a multiphase system, composed of YAP, YAG, and mono-clinic yttrium aluminate (YAM) phases. However, a short heat treatment with a high heating rate (200 °C/min) at higher temperatures results in the formation of a kinetically favoured pure YAP hexagonal phase. On the other hand, for a predefined Y/Al ratio of 3:5, the generation of a thermody-namically favoured pure YAG phase has been confirmed, re-gardless of the applied heat-treatment conditions. Although incomplete, Ce³⁺ introduction into the host matrix has been detected by XRPD and luminescence measurements.The authors gratefully acknowledge the Ministry of Science and Education of the Republic of Serbia (Project No 172035), the University Carlos III (Madrid, Spain), and the Santander Bank (Chairs of Excellence Program for the academic year 2010–2011) for financial suppor

Poređenje kvaliteta mesa linjaka i šarana

U poslednje dve godine postoje veliki problemi u plasmanu slatkovodnih riba proizvedenih na našim ribnjacima. Zahvaljujući nekontrolisanom uvozu, došlo je do toga da se na našem tržištu nađe velika količina jeftinih vrsta riba, pre svega Pangasius pangasius iz Vijetnama , čiji je uvoz zabranjen u mnogim razvijenim zemljama, pre svega SAD, Kanadi i većem broju zemalja Evropske Unije. Velprodajna cena šarana je veoma niska, pa je doveden u pitanje opstanak naše ribarske privrede, u čijoj strukturi šaran učestvuje najvećim delom. Stoga je potrebno razmišljati o uvođenju drugih slatkovodnih vrsta koje bi se mogle plasirati na tržište Evropske Unije, što se pre svega odnosi na linjaka. Takođe, treba razmišljati i o organskoj proizvodnji riba i o kreatnju ka ekstenzivnijim metodama gajenja. Neophodno je voditi računa i o nutritivnom kvalitetu mesa jer se od ribarske privrede očekuje proizvod sa niskim sadržajem masti i povoljnim odnosom nezasićenih masnih kiselina, pre svega ω-3 i ω-6 masnih kiselina. Poznat je povoljan uticaj ω-3 polinezasićenih masnih kiselina (PNMK) iz mesa ribe na zdravlje čoveka, kao i da povećana potrošnja ribe utiče na sprečavanje nastanka oboljenja kardiovaskularnog sistema, kao i u prevenciji inflamatornih, autoimunih i malignih oboljenja, dijabetesa i drugih bolesti. Literalni podaci o randmanu dvogodišnjih riba linjaka i šarana su veoma oskudni, dok su dostupne informacije o konzumnim ribama koje su starosti tri i više godina. Kako kvalitet mesa zavisi od starosti jedinke, neophodna su istraživanja i o kvalitetu mesa mlađih kategorija riba. Osim randmana analizirani su i hemijski sastav mesa dvogodišnjeg linjaka i šarana sa akcentom na zastupljenost masnih kiselina i poređenje odnosa ovih vrednosti kod linjaka i šarana. Uzorci dvogodišnjeg linjaka i šarana uzeti su na oglednom ribnjaku "Mošorin". Proizvodnja ovih riba odvijala se u ekstenzivnom sistemu, gde je povećanje organske produkcije vršeno pregorelim goveđim i ovčijim stajnjakom. Ishrana dodatnim hranivima nije vršena. U pripremi objekta i tokom vegetacionog perioda korišćen je hidratni kreč. Analize hemijskog sastava i masnokiselinskog sastava lipida ribe su izvršene u Institutu za higijenu i tehnologiju mesa, Beograd. Analizom morfometrijskih karakteristika ribe utvrđena je dobra kondicija. Randman mesa linjaka povoljniji je od istoga kod šarana što se može objasniti manjom masom digestivnog trakta ove vrste. Razlog za niži procenat proteina kod linjaka i kod šarana nego što je to prikazivano u klasičnoj literaturi je što se radi o mesu dvogodišnjih riba dok se pomenuti literaturni podaci odnose na starije kategorije koje imaju manji sadržaj vode. Veći sadržaj vode kod dvogodišnjih riba doprinosi boljem gastronomskom kvalitetu mesa. Po sadržaju masti meso linjaka je približno vrednostima tolstolobika i amura, iz čega se može zaključiti da je veoma pogodno kao dijetalna hrana za potrebe posebnih zdravstvenih kategorija ljudi. I dvogodišnji šaran ima nizak procenat masti iz čega se može zaključiti da šaran ne spada u masne ribe jer ima niži procenat sadržaja masti od pastrmke. Tehnologija gajenja odnosno vrsta dodatne ishrane je najodgovornija za procenat masti. Odnos nezasićenih masnih kiselina kod linjaka povoljniji je nego kod šarana i pastrmke i u sličnom nivou je sa istim kod morskih vrsta riba. Meso dvogodišnjih riba po svom hemijskom sastavu ima prednost u odnosu na meso riba gajenih u trogodišnjem i višegodišnjem sistemu gajenja. Ekstenzivni sistem ima prednost u kvalitetu mesa ali treba analizirati njegovu ekonomsku opravdanost. Kvalitet mesa linjaka je izuzetnih nutritivnih vrednosti što je razlog za njegovu reintrodukciju i repopulaciju. Meso riba visoke nutritivne vrednosti ima perspektivu kao izvozni artikal u zemlje Evropske Unije i druge razvijene zemlje

Determination of Capacity and Rules of the Variability of Maximum Force Using Nonlinear Mathematical Models: a Case Study.

The aim of this study is to determine the capacity and the variability of maximum force rules measured 1 RM for eight muscle groups (back-hip extensors, legs extensors, arm extensors, back extensors, shoulder and arms extensors, shoulder joint flexors, hip and knee extensors, trunk flexors). The determination was performed on the experimental results of the top basketball center player using repeated measurements and nonlinear mathematical models methods. Changes in maximum force were induced with 8 months of weight lifting training and analised with nonlinear regression analysis within 95% confidence interval. The results indicate that from all the models applied only the Asymptotic Regression, Michaelis-Menten and Gompertz Growth models had satisfactory performance and provided solid solutions to the given problem. This means that the models developed in this study properly and reliably determine the capacity and predicted changes in the maximum force (1 RM) for all eight monitored muscle groups

Structural, morphological and luminescence properties of nanocrystalline up-converting Y1.89Yb0.1Er0.01O3 phosphor particles synthesized through aerosol route

Nanocrystalline up-converting Y₂ O₃Yb³⁺ Er³⁺ phosphor particles were processed in a dispersed system-aerosol, generated ultrasonically at 1.3 MHz from common nitrate precursor solution having fixed ytterbium-to-erbium concentration ratio. The appropriate process parameters: residence time 21 s, carrier gas (air) flow rate 1.6 dm3/min, synthesis temperature 900 °C, led to the formation of un-agglomerated spherical nanostructured secondary particles, having mean particle size of approx 450 nm, composed of primary nanoscaled (20 nm) subunits. In order to reach targeting phase crystallinity, the as-prepared particles were additionally annealed at 1100 °C in air for 12, 24 and 48 h, respectively. Particle structure, morphology and purity were analyzed by X-ray powder diffraction (XRPD), scanning electron microscopy (FESEM/SEM), analytical and high resolution transmission electron microscopy (TEM/HRTEM) in combination with energy dispersive X-ray analysis and Fourier Transform Infrared Spectroscopy (FTIR). All samples crystallized in a cubic bixbyte-structure, space group Ia-3. The crystallite size changed with annealing time from 30 nm in as-prepared sample to 135 nm in sample annealed for 48 h, respectively. Emission spectra were assigned to the following trivalent erbium f–f electronic transitions: ²H₉/₂ → ⁴I₁₅/₂ (blue: 407–420 nm), (²H₁₁/₂̦ ⁴S₃/₂) → ⁴I₁₅/₂ (green: 510–590 nm), and ⁴F₉/₂ → ⁴I₁₅/₂ (red: 640–720 nm). The significant improvement of the emission decay times were observed after thermal treatment and this effect is correlated further with the structural and morphological particles characteristics. For the anneal-ing time of 12 h a quite high emission decay times were achieved (blue: 0.14 ms, green: 0.32 ms and red: 0.39 ms).This research is financially supported through the Project #172035 of the Ministry of Science and Education of the Republic of Serbia. OM especially acknowledge the University Carlos III, Madrid, Spain-Santander Bank Chairs of Excellence program and JSPS 2011/2012 fellowship, Japan.Publicad

Development of Expert System for the Selection of 3D Digitization Method in Tangible Cultural Heritage

Selection of an appropriate 3D digitization method in the field of cultural heritage represents a big challenge, especially for non-expert users, such as conservators, art historians, archaeologists etc. Considering the above, the aim of this paper is to develop an expert system for the selection of 3D digitization method, which is the tool for suggesting for the most acceptable 3D digitization method for any individual cultural heritage object. The development of the expert system was presented through the analysis of its components, i.e. main modules – user interface, database and knowledge base. This expert system was based on different parameters defined through theoretical-methodological analysis of representative tangible cultural heritage objects. The database contains technical specifications of various 3D digitization methods, devices, and additional equipment available on market, while the knowledge base defines their limitations. The expert selection system requires as input information details about the cultural heritage object and the end user requirements. During the evaluation phase through the case studies, the system proposed satisfactory solutions depending on the entered input data