Trends of forest area and population and the impact of population on forest area per hectare in Serbia without APS

Socio-economic changes throughout history have shaped the attitude towards the forest and most significant ones are changes in terms of population. Over the centuries population and population density have had a significant impact on deforestation and the reduction of forest areas. Therefore, it is important to check what kind of trends are concerned and how population growth affects forest areas, forest cover and forest area per capita. These elements are important for assessing the direction, intensity of activity and the degree of success in the implementation of all forest policy measures in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanja klimatskih promena i njihovog uticaja na životnu sredinu - praćenje uticaja, adaptacija i ublažavanje, podprojekat, br. 43007/16-III: Socio-ekonomski razvoj, ublažavanje i adaptacija na klimatske promene

Wood dimensions and value in the Austrian pine plantations in Forest Estate "Sombor"-Forest Unit "Subotica"

The relationship and interaction between quantitative (number and dimensions of trees) and value indicators in Austrian pine plantations were researched in Forest Management Unit „Subotičke Šume” (Forest Estate „Sombor” - FA „Subotica”). As the measurement of quantitative elements is more simple, their effect on wood value can be used as a rather reliable support in the value estimation of standing trees. The analysis of the research results shows that there is a strong inter-relationship of the study elements, so they can be a good foundation for the estimation of standing timber value in artificial Austrian pine plantations at the given site

Typology of the supply chains of non-wood forest products in central Serbia

Modern economies are characterized by a growing importance of cooperation and the creation of networks of enterprises, organizations and institutions, which are all part of a supply chain, in order to achieve competitive advantage in a market. The aim of this study was to determine the structure of the supply chains of non-wood forest products in selected forest areas of Central Serbia (Golijsko, Podrinjsko-kolubarsko, Posavsko-podunavsko, Rasinsko and Tarsko-zlatiborsko FAs). The comparative method was applied in this paper, along with the method of specialization (classification), the method of structural partial analysis (supply chain analysis) and the statistical method (analysis of frequencies and two-step cluster). The data collection was conducted in 2011, by using the technique of door-to-door survey. The analysis of the basic types of the supply chains of non-wood forest products and their main stages (purchasing, processing and placement) was conducted in the selected areas. A cluster analysis showed that there were six basic types of supply chains in the selected forest areas and one dominant type. [Projekat Ministarstva nauke Republike Srbije, br. 443007/16 –III: Istraživanja klimatskih promena i njihovog uticaja na životnu sredinu -praćenje uticaja, adaptacija i ublažavanje, podprojekat: Socio-ekonomski razvoj, ublažavanje i adaptacija na klimatske promene

ASCORBIC ACID MODULATES SPONTANEOUS THYMOCYTE APOPTOSIS

The aim of the paper was to analyze the effect of various concentrations of ascorbic acid on spontaneous apoptosis of lymphocytes.About 58% of all thymocytes are subjected to a spontaneous apoptosis, after 24-hour cultivation in the complete medium. The number of apoptotic thymocytes was much lower in the culture with different concentrations of ascorbic acid. The most dramatic effect was detected in the culture with the highest concentration of ascorbic acid (10000 μg/ml). In this culture, the number of apoptotic thymocytes was about 32%. These results, compared with the results of spontaneous apoptosis, show that the most significant inhibition of apoptosis was detected in the culture with 10000 μg/ml of ascorbic acid. High concentration of ascorbic acid can inhibit spontaneous apoptosis of thymocytes. Such inhibition of T cell apoptosis, as the effector cells in immune system, can represent one of the major factors by which ascorbic acid influence the immune system

Mehanizmi financiranja sustava upravljanja zaštićenim područjima u Srbiji

The financing of protected area (PA) management includes the interaction of different actors that are involved in the process of management and financing, i.e., from the management framework to the mechanisms of financing. The management framework sets the basic preconditions for PA management, while the mechanisms of financing represent the ways of financing PAs based on the long-term and sustainable conditions. The management of PAs in Serbia has mostly been done by public enterprises (PE). It was given to non-governmental organizations (NGO) for the first time in the late 1990s. Today, the management is carried out by different managers from the public sector (PS) to the private sector (PrS). This research deals with different financing mechanisms present in PAs in Serbia. Additionally, it deals with the differences in the financing between different management actors (MA) in order to establish the best financing practices in the PA management system in Serbia. The results indicate that public enterprise “Srbijašume” (PES) has the lowest average number of financial sources, unlike public enterprise “Vojvodinašume” (PEV). Regarding the average amount of financing, other managers from the public sector (OPS) have the largest amount of financing, while other public enterprises (OPE) record the smallest amount of their own financing. In order to improve the use of mechanisms for the PA management system financing, additional training for the use of funds is proposed at national and international level, as well as external, i.e., additional engagement of agencies that would prepare projects at international level. It is also proposed to establish a specific mechanism – a fund intended for nature protection.Financiranje upravljanja zaštićenim područjima (ZP) uključuje interakciju različitih dionika koji su uključeni u proces upravljanja i financiranja, tj. od okvira upravljanja do mehanizama financiranja. Upravljački okvir postavlja osnovne preduvjete za upravljanje ZP, dok mehanizmi financiranja predstavljaju načine financiranja ZP na temelju dugoročnih i održivih uvjeta. Upravljanje ZP može se delegirati organizaciji, pojedincu ili zajednici, koja funkcionira u skladu s nizom zakona, pravila i / ili tradicijom. Isto tako, upravitelji ZP mogu se podijeliti na temelju toga tko donosi odluke i može se smatrati odgovornim. Jedna od važnih komponenti upravljanja ZP predstavlja održivo financiranje, što predstavlja temelj za ostvarivanje zaštite prirode. Održivo financiranje definira se kao sposobnost pružanja dovoljnih, stabilnih i dugoročnih financijskih izvora. Upravljanje ZP u Srbiji uglavnom provode javna poduzeća, dok je krajem devedesetih godina u Srbiji upravljanje ZP po prvi put dodijeljeno nevladinim organizacijama. Danas upravljanje provode različiti upravitelji iz javnog sektora i privatnog sektora. Planirano povećanje ZP u Srbiji uključuje skoro dvostruko veću površinu od sadašnje pokrivenosti i ta će činjenica stvoriti dodatnu obavezu za postojeće i nove upravitelje u budućem razdoblju, jer je održivo upravljanje ZP postalo izazov, kako sa upravljačkog, tako i sa financijskog gledišta. Ovo istraživanje bavi se različitim mehanizmima financiranja koji su prisutni u ZP u Srbiji. Također, bavi se razlikama u financiranju između različitih grupa upravitelja, kako bi se uspostavile najbolje prakse financiranja u sustavu upravljanja ZP u Srbiji. U fazi prikupljanja podataka korištena je anketa od vrata do vrata. Istraživanje se provodilo u dvije faze. U prvoj fazi, populacija za istraživanje definirana je na temelju registra ZP, od čega su izdvojena 63 ZP. U drugoj fazi, uzorak za istraživanje definiran je na temelju primjera „dobre prakse“ upravitelja ZP i predstavnika javne uprave i službi, kao i organizacija u sustavu upravljanja ZP. Za obradu podataka korištena je deskriptivna statistika, frekvencijska analiza, Kruskal-Wallis-ov test i Mann-Whitney-jev U test. Kruskal-Wallis-ov test korišten je za određivanje razlika između svih grupa upravitelja, dok je Mann-Whitney-jev U test korišten za određivanje razlika između pojedinih grupa upravitelja. Rezultati pokazuju da javno poduzeće “Srbijašume” ima najmanji prosječan broj izvora financiranja, za razliku od javnog poduzeća “Vojvodinašume” (tablica 1). Što se tiče prosječnih iznosa financiranja, najveći dio financiranja imaju ostali upravitelji iz javnog sektora, dok ostala javna poduzeća bilježe najmanji iznos vlastitog financiranja (tablica 2). Na temelju rezultata prve faze istraživanja predloženi su elementi unaprjeđenja sustava upravljanja ZP za mehanizme financiranja (tablica 3). Predstavnici upravitelja ZP, javne uprave i službi, kao i organizacija, smatraju da politička volja donositelja odluka, kao i nepostojanje razumijevanja države za potrebe financiranja ZP, ima velik utjecaj na unaprjeđenje postojećih mehanizama financiranja. Također, predstavnici sve tri skupine vjeruju da lokalne vlasti nisu ni uključene u financiranje ZP-a i da postoji nedovoljna zainteresiranost drugih institucija. Kao problem u unaprjeđenju korištenja domaćih i međunarodnih izvora financiranja, predstavnici upravitelja ZP vide potrebu za dodatnim istraživanjima i problemom nedovoljne izobrazbe upravitelja, za podnošenje projektnih ideja, koje su vezane uz nedovoljnu informatičku pismenost

Identifikacija nelinearnog strukturnog ponašanja pomoću digitalne povratne neuronske mreže

Dynamical systems contain nonlinear relations which are difficult to model with conventional techniques. Hence, efficient nonlinear models are needed for system analysis, optimization, simulation and diagnosis of nonlinear systems. In recent years, computational-intelligence techniques such as neural networks, fuzzy logic and combined neuro-fuzzy systems algorithms have become very effective tools in the field of structural identification. The problem of the identification consists of choosing an identification model and adjusting the parameters in an way that the response of the model approximates the response of the real system to the same input. This paper investigates the identification of a nonlinear system by Digital Recurrent Neural Network (DRNN). A dynamic backpropagation algorithm is employed to adapt weights and biases of the DRNN. Mathematical model based on experimental data is developed. Results of simulations show that the application of the DRN for the identification of complex nonlinear structural behaviour gives satisfactory results.Dinamički sustavi sadrže nelinearne veze koje se teško modeliraju konvencionalnim tehnikama. Nelinearni modeli su neophodni za analizu sustava, optimizaciju, simulaciju i dijagnostiku nelinearnih sustava. Prethodnih godina, tehnike računalne inteligencije kao što su neuralne mreže, fuzzy logika i kombinirani neuro-fuzzy sustavi postaju efikasni alati u identifikaciji nelinearnih objekata. Problem identifikacije se sastoji od izbora identifikacijskog modela i prilagođavanja parametara tako da odziv modela aproksimira odziv realnog sustava za isti ulaz.Ovaj rad proučava identifikaciju nelinearnih sustava pomoću digitalne povratne neuronske mreže. Dinamički algoritam s propagacijom pogreške unazad se primjenjuje za adaptaciju težina i pragova osjetljivosti DRNN. Matematički model se razvija na bazi eksperimentalnih podataka. Rezultati simulacija pokazuju da primjena DRN u identifikaciji kompleksnog nelinearnog strukturnog ponašanja daje zadovoljavajuće rezultate

Direct and Joint Effects of Genotype, Defoliation and Crop Density on the Yield of Three Inbred Maize Lines

The aim of this study was to observe direct and joint effects of three factors (genotypes, ecological environmental conditions and the applied crop density) on the level of defoliation intensity and yield. Three inbred lines (G) of maize (G1–L217RfC, G2–L335/99 and G3–L76B004) were used in the study. The trials were performed in two years (Y) (Y1 = 2016 and Y2 = 2017) and in two locations (L) (L1 and L2) under four ecological conditions of the year–location interaction (E1–E4) and in two densities (D1 and D2) (50,000 and 65,000 plants ha−1 ). Prior to tasselling, the following five treatments of detasseling and defoliation (T) were applied: T1—control, no leaf removal only detasseling, T2–T5—removal of tassels and top leaves (from one to four top leaves). The defoliation treatments had the most pronounced effect on the yield reduction in G1 (T1–Tn+1 . . . T5), p < 0.05. The ecological conditions on yield variability were expressed under poor weather conditions (E3 and E4), while lower densities were less favorable for the application of defoliation treatments. The result of joint effects of factors was the lowest grain yield (896 kg/ha) in G3 in the variant E3D1 for T2 and the highest grain yield (11,389 kg/ha) in G3 in the variant E2D2 for T1. The smallest effect of the defoliation treatment was on the kernel row number (KRN

Direct and Joint Effects of Genotype, Defoliation and Crop Density on the Yield of Three Inbred Maize Lines

The aim of this study was to observe direct and joint effects of three factors (genotypes, ecological environmental conditions and the applied crop density) on the level of defoliation intensity and yield. Three inbred lines (G) of maize (G1-L217RfC, G2-L335/99 and G3-L76B004) were used in the study. The trials were performed in two years (Y) (Y1 = 2016 and Y2 = 2017) and in two locations (L) (L1 and L2) under four ecological conditions of the year-location interaction (E1-E4) and in two densities (D1 and D2) (50,000 and 65,000 plants ha−1). Prior to tasselling, the following five treatments of detasseling and defoliation (T) were applied: T1-control, no leaf removal only detasseling, T2-T5-removal of tassels and top leaves (from one to four top leaves). The defoliation treatments had the most pronounced effect on the yield reduction in G1 (T1-Tn+1… T5), p < 0.05. The ecological conditions on yield variability were expressed under poor weather conditions (E3 and E4), while lower densities were less favorable for the application of defoliation treatments. The result of joint effects of factors was the lowest grain yield (896 kg/ha) in G3 in the variant E3D1 for T2 and the highest grain yield (11,389 kg/ha) in G3 in the variant E2D2 for T1. The smallest effect of the defoliation treatment was on the kernel row number (KRN)

Kanali distribucije u savremenom bankarstvu

U savremenim uslovima neizvesnog i izuzetno konkurentnog okruženja banke su izložene velikom pritisku unapređenja kvaliteta usluga, uz istovremeno smanjenje troškova poslovanja. U uslovima u kojima cenovna konkurentnosti ne obezbeđuje dovoljan prostor za tržišno pozicioniranje, banke su suočene sa imperativnom poboljšanja korisničkog servisa. Navedena tendencija je posebno izraženo za retail bankarski segment, pri čemu kanali distribucije igraju ključnu ulogu u pružanju kvalitetnijeg korisničkog iskustva, jer interakcije sa klijentima počinju i završavaju u okviru kanala distribucije. Korisnici bankarskih usluga očekuju sve veću udobnost, dostupnost, personalizaciju i pouzdanost kanala bankarskih distributivnih mreža. Da bi ostvarile postavljene zahteve korisnika banke se u velikoj meri oslanjaju na mogućnosti i novitete informaciono-komunikacione tehnologije. Aktuelnost predložene teme predstavljala osnovnu motivaciju autorima ove monografije posvećene analizi razvoja i trendova u oblasti elektronskog bankarstva, kanala distribucije i elektronskih transakcija. Autori priloga predstavili su rezultate analize pojedinih tema koji dominantno targetiraju segment kanala u savremenom bankarstvu. Osvrt na istorijski razvoj elektronskog bankarstva, sa akcentom na uticaj i prilagođavanje bankarskog poslovanja inovacijama koje je donosio revolucionarni razvoj informaciono-komunikacione tehnologije. Posebna dimenzija prvog poglavlja predstavlja i analizu najnovijih trendova u Srbiji. U okviru drugog poglavlja detaljno su opisani rizici sa kojima se banke suočavaju u domenu elektronskog bankarstva, a pored pregleda situacije u Srbiji, dat je pregled i za Bosnu i Hercegovinu, Crnu Goru i Hrvatsku. Treće poglavlje je posvećeno izazovima kojima se banke suočavaju u retail sektoru kada su u pitanju elektronski kanali distribucije. Predstavljeni su rezultati analize trendova koji utiču na promene u bankarskim kanalima distribucije. Poglavlje obuhvata i kriterijume za izbor optimalne strategije kanala distribucije. Veoma važna tema, razvoj i trendovi u oblasti platnih kartica vrlo detaljno je predstavljena u četvrtom poglavlju. Centralni deo monografije, peto poglavlje, posvećeno je vrlo aktuelnoj temi – mogućnostima primene društvenih mreža u bankarstvu. Poglavlje obrađuje fenomen Interneta i Web 2.0 tehnologije i servisa bazirane na njoj. Tema je obrađena kroz dve perspektive: korisnika bankarskih usluga i banaka. Logičan nastavak ove teme su inovacije u mobilnom bankarstvu, obrađenu u šestom poglavlju. Rast potreba korisnika za lagodnijim i lakšim upravljanjem bankovnim računima i drugim bankarskim uslugama morali su zadovoljiti i proizvođači mobilnih telefona, a to se pre svega odnosi na razvoj aplikacija kao što su Google Walet i Apple Pay. Poslednja, treća glava monografije obuhvata temu elektronskih transakcija. Sedmo poglavlje obrađuje vrlo važnu i kompleksnu oblast – razmenu poslovnih transakcija. Obuhvaćena je analiza rada klirinških kuća, kao i rešenja za elektronska plaćanja poput MultiChain, Blue Mix i Bitcoin. Osmo poglavlje doprinosi kvalitetu monografije prikazom rezultata analize navika koje građani Srbije imaju u onlajn transakcijama u poređenju sa građanima razvijenih zemalja Evropske unije