Interactive multimedia in teaching mathematics

This PhD thesis presents the benefits and importance of using multimedia in the math classes using selected examples of multimedia lessons from isometric transformations, regular polyhedral and definite integral. The research presented in the thesis was carried out among 150 first year students of the Faculty of Architecture, the Faculty of Civil Construction Management and the Faculty of Entrepreneurial Business of the UNION "Nikola Tesla" University, Belgrade, Serbia. Each group of 50 students was divided into two equal groups of students, one of which had the traditional lectures, while the other one had the interactive multimedia lessons. All three topics were presented to students of the Faculty of Architecture and the Faculty of Civil Construction Management while only definitive integral was presented to students of the Faculty of Entrepreneurial Business. The main source of information in multimedia lectures were the software’s created in Macromedia Flash, with the same definitions, theorems, examples and tasks as well as in traditional lectures but with emphasized visualization possibilities, animations, illustrations, etc. Both groups were tested after the lectures. In the multimedia groups students showed better theoretical, practical and visual knowledge. Besides that, survey carried out at the end of the research clearly showed that students from multimedia groups were highly interested in interactive multimedia learning

Preliminary monitoring results of ventilated heavyweight building envelope from recycled aggregate

Potential of recycled aggregate concrete (RAC) has already been acknowledged by many researchers, but the focus was primarily on its mechanical and durability properties at material level. If the focus is shifted to element and whole building level, then the question can be raised; how building envelopes made from RAC behave when exposed to real environment? The present paper describes an experimental set up to monitor hygrothermal behaviour of one three-storey family house built with prefabricated ventilated sandwich wall panels made from recycled concrete and recycled brick aggregate. This type of building envelope can be classified as a heavyweight envelope. In ground-floor flat a wall in the living room facing south is analysed in terms of internal temperature evolution and humidity distribution. Conditions of indoor and outdoor environment were monitored as well. Time lag and decrement of temperature extremes were observed and these benefits can be attributed to the presence of thermal mass. Ventilation of air in cavity ensured acceptable humidity level in all characteristic layers of wall panel. Summer overheating occurred due to insufficiently shaded large transparent openings. Further step is validation of numerical model and assessing the suitability of presented envelope type to different climates. This paper indicates the great potential of RAC application in energy efficient and moisture safe building envelope design

Proclivity for open innovation in the case of agricultural and food companies in Serbia

The approach to open innovation presents one of the major trends in terms of constant change and accelerating technological innovation. The given construct proclivity for open innovation involves measuring technology exploration and technology exploitation involving different inside-out and outside-in open innovation activities. In this paper, we are researching the tendency for open innovation on a sample of 102 companies in the agriculture and food sectors in Serbia. The research has shown that companies in the agro-food sector are inclined to open innovation, not just those in high-tech industries that are often the subject of innovation literature. The food sector shows greater proclivity for open innovation in comparison with agriculture in all elements apart from the question of willingness to sell intellectual property. The study was limited to Serbia and cross-countries research would allow establishing the specificities and differences of the proclivity for open innovation in the agro-food sector by regions

How to achieve Nearly zero-energy buildings standard

Implementacijom standarda zgrade gotovo nulte energije (NZEB) došlo je do značajnog razvoja projektiranja i izvođenja vanjske ovojnice zgrade koja ima najveći utjecaj na kvalitetu zgrade u smislu energetske učinkovitosti. Praksa pokazuje da za kvalitetno izvođenje radova treba kompetentna i motivirana radna snaga, odgovarajuća oprema i dobra komunikacija između svih sudionika u građenju. U radu su prikazani osnovni principi arhitektonsko-građevinskog projektiranja i izvođenja NZEB-a te su predočeni problemi koji se javljaju i mogu rezultirati građevinskom štetom.The implementation of the Nearly zero-energy buildings (NZEB) standard has enabled significant developments in the design and realisation of external building envelopes, which have the greatest influence on the quality of buildings in the sense of energy efficiency. Experience has shown that prerequisites for good-quality realisation of works mainly include competent and motivated workforce, appropriate equipment, and good communication between all participants in construction. Basic principles of architectural and civil engineering design and realisation of NZEB projects are presented, and problems occurring and possibly resulting in construction damage are presented in the paper

Laparoskopsko osemenjavanje ovaca u Republici Srbiji

This paper describes a procedure of laparoscopic insemination (LAI) performed in 42 Ile de France ewes with deep-frozen rams' semen. Frozen semen doses was imported from France, originating from two rams (A and B), and used intermittently in three LAI cycles on different females. The ewes were examined ultrasonographically for pregnancy, two months following insemination and data of lambing were recorded at the end. Total achieved lambing rate was 61.90% (26/42) and total number of lambs was 49 (prolificacy 1.88; 1.16 lambs per sheep included in LAI protocol). Three labs from 2 ewes were stillborn and one dyed at 10th day after lambing. Lambing rates for rams A and B were 53.85% (14/26) and 75.00% (12/16), respectively. Introduction of laparoscopic insemination of sheep with imported deep-frozen semen of top quality rams, gaining technical experience and achieving conception rate over 65% could make this technique acceptable in improving genetic potential of top quality sheep flocks.U radu je opisan postupak laparoskopskog osemenjavanja (LAO) primenjen kod 42 ovce rase Ile de France duboko zamrznutim semenom. Tokom tri ciklusa osemenjavanja naizmenično je korišćeno seme dva ovna (A i B), uvezeno iz Francuske. Nakon dva meseca od osemenjavanja ovce su pregledane na sjagnjenost ultrasonografskom metodom i analizirani su podaci o jagnjenju. Ostvarena je koncepcija od 61,90% (26/42) i dobijeno je ukupno 49 jaganjaca (indeks jagnjena 1,88 po ojagnjenoj ovci, odnosno, 1,16 jagnjeta po ovci uključenoj u protokol LAO). Tri jagnjeta od dve ovce bila su mrtvorođena i jedno jagnje je uginulo 10. dana nakon jagnjenja. Sjagnjenost od semena ovna A iznosila je 58,85% (14/26) a od ovna B 75,00% (12/16). Uvođenje laparoskopskog osemenjavanja ovaca, uvoz duboko-zamrznutog semena vrhunskih ovnova, sticanje iskustva i ostvarenje koncepcije od preko 65% može ovu tehniku učiniti prihvatljivom u popravljanju genetskog potencijala kvalitetnih stada ovaca

Leaf morphometric characteristics variability of different beech provenances in juvenile development stage

The taxonomic status of beech from the Balkan Peninsula is not yet clearly defined. There is no agreement among different authors about the morphological characteristics discriminating between the Balkan and European and/or Eastern beech. For most characteristics, the mean values are different but the ranges of variation overlap considerably. Provenance trial of beech established in Serbia, at the locality Debeli Lug, has provided an opportunity for research of interprovenance variability at the level of leaf morphometric characteristics in juvenile development stage. Research included 10 provenances originating from the Western Balkans (Serbian provenance 36 and 38; Croatian provenance 24 and 25; Bosnian provenance 30 and 32) and from Central Europe (German provenance 47 and 49; Austrian provenance 56 and Hungarian provenance 42), where following morphometric characteristics were analyzed: leaf length (Ll), leaf width (Lw), petiole lenght (Pl), leaf base width on 1 cm (Blw), number of veins - left (Vl), number of veins - right (Vr), distance between 3rd and 4th vein - left (Dv 3-4). The results of this research show existence of clear differentiation among provenances from the Western Balkan and from Central Europe, from the point of leaf dimensions, number of veins and leaf base width. [Projekat Ministarstva nauke Republike Srbije, br. TR31041: Establishment of Wood Plantations Intended for Afforestation of Serbia i br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation

Leaf morphometric characteristics variability of different beech provenances in juvenile development stage

The taxonomic status of beech from the Balkan Peninsula is not yet clearly defined. There is no agreement among different authors about the morphological characteristics discriminating between the Balkan and European and/or Eastern beech. For most characteristics, the mean values are different but the ranges of variation overlap considerably. Provenance trial of beech established in Serbia, at the locality Debeli Lug, has provided an opportunity for research of inter-provenance variability at the level of leaf morphometric characteristics in juvenile development stage. Research included 10 provenances originating from the Western Balkans (Serbian provenance 36 and 38; Croatian provenance 24 and 25; Bosnian provenance 30 and 32) and from Central Europe (German provenance 47 and 49; Austrian provenance 56 and Hungarian provenance 42), where following morphometric characteristics were analyzed: leaf length (Ll), leaf width (Lw), petiole lenght (Pl), leaf base width on 1 cm (Blw), number of veins-left (Vl), number of veins - right (Vr), distance between 3(rd) and 4(th) vein - left (Dv 3-4). The results of this research show existence of clear differentiation among provenances from the Western Balkan and from Central Europe, from the point of leaf dimensions, number of veins and leaf base width