Uticaj naučno-tehnološke i industrijske revolucije na rani razvoj poljoprivredne tehnike

Although the early applications of the agricultural mechanization can be dated in the I century b.c., the intensive use of the machines in agriculture started in the XIX century, as a result of the scientific and tecnical development. Taking this into account in this article the influence of scientific revolution and industrialisation on agricultural engineering has been presented.Počeci primene sredstava poljoprivredne mehanizacije sežu još u I vek nove ere, ali tek u XIX veku zahvaljujući naglom razvoju nauke i tehnike dolazi do značajnije primene mašina u poljoprivredi. Imajući to u vidu, u ovome radu sagledan je uticaj naučne revolucije i industrijalizacije na rani razvoj poljoprivredne tehnike

Cut Length Distributions of Haylage Particles

Alfalfa is one of the most important crops for forage production. Traditional method of alfalfa conservation assumes hay preparation. However, nowadays it is also commonly processed in the form of silage and haylage. Physiological effects of forages that are included in diets depend on plant species, stage of maturity, method of preservation and diet composition. Physical characteristics of rations for ruminants are primarily influenced by dietary forage to concentrate ratio, type of forages and concentrates, and mean particle size of feeds. Length distribution of forage particles represents an important parameter for ruminant’s diet formulation, especially for dairy cattle. During silage production, harvest considerations should be focused to obtaining the adequate particle size distribution of the ensiling crop particles. This paper presents results of testing three contemporary types of self-propelled silage harvesters applied in the alfalfa haylage preparation: Claas Jaguar 950, Krone Big X 700 and Krone Big X 500. All machines were adapted with pick-up headers. In the study are analyzed length distributions of chopped alfalfa particles. Resulting frequency distributions of produced haylage are characterised by high mass percentage of the fraction comprehending the largest particles. It is also evident that harvester Class Jaguar 950 achieved the mean chopping length closest to preset value

Ostvareni obim korišćenja sredstava poljoprivredne tehnike kao element za donošenje odluke pri organizovanju mehanizovanih procesa na poljoprivrednim gazdinstvima

The paper presents a method to be based on known economic laws made the decision making that provides increased levels of economic efficiency of use of agricultural mechanization. It is one of the basic tasks necessary precondition for achieving competitiveness in the market of agricultural products, as well as a necessary part of the transformation of rural economies in order to survive.U radu je prikazan metod kako se na bazi poznatih ekonomskih zakonitosti vrši donošenje odluke koja obezbeđuje povećanje nivoa ekonomske efektivnosti korišćenja poljoprivredne tehnike. To je jedan od osnovnih zadataka i neophodan preduslov za dostizanje konkurentnosti na tržištu poljoprivrednih proizvoda, kao i neophodan segment transformacije seoskih gazdinstava u cilju njihovog opstanka

Combines Work Quality in Maize Silage Production

The paper presents testing results of three silage combines employed in maize silage preparation in Toplica region. It is focused on determination of technical working parameters of tested machines. Achieved results verified the superiority of silage combine John Deere 5820, which produced the chopped mass having particle lengths of the smallest deviation with respect to the preset cutting length. In this case, the average length of chopped mass was 9.9 mm, having 69 % mass in the range up to 8 mm. The other two silage combines produced lower mass percentage of this fraction and larger variations of particle lengths with respect to the preset length. Minimum mass flow rate was evidenced for the silage combine Fortschrit E-286: 7.3 kg s-1 (26.3 t h-1) and the surface productivity of 0.83 ha h-1, at the average speed of 4.0 km h-1. Maximum production rate was achieved with silage combine John Deere 5820: 10.9 kg s-1 (39.1 t h-1) at average working velocity of 4.7 km h-1 and surface efficiency of 1.21 ha h-1

Priprema i potencijal ostataka rezidbe u voćnjacima i vinogradima kao energetskog materijala

Huge amounts of plant remains are obtained following pruning, an essential agricultural practice measure during the exploitation of orchards and vineyards. Different pruning modes are employed depending on the size of the orchard and the available machinery. The remains tend to hinder other activities in the orchard but on the other hand they represent an essential energetic source. The energy can be transformed or returned into soil by mulching. Collecting and burning of the remains but also further cutting into small pieces and plowing itself were elimination modes of former technologies. However, these procedures contributed to the loss of a useful and important source of heat energy. Optimal technological and technical solutions should be defined with regard to collecting, loading, transporting and preparing pruning remains in orchards and vineyards with the aim of obtaining energy. This is expected to have a significant influence on the energetic efficiency of fruit growing and is an issue of major concern. In our country collecting, preparing and using pruning remains is not widely used due to the irrational disposal of energy and extensive production. Pruning remains have their advantage as sustainable energy source being at the site of consumption or its vicinity. The simplest and oldest way of using pruning remains as energents in the process of burning and producing heat energy is to burn the unchanged remains. Considering the bulk of it which is characterized by the irrational transport, impeded loading, unloading, storing and use in combustion equipments. Ecological issues and fossil energy deficiency impose the need to focus on the preparation and use of pruning remains as energetic fuel in orchards. The issue has gained in importance following the regulations imposed by the EU whereby renewable energy sources should be used in the production of electrical energy. The aim is to solve the lack of eco energy and contribute to environmental protection.Tokom eksploatacije višegodišnjih zasada pored ostalih kao obavezna agrotehnička mera sprovodi se i rezidba kojom se dobija velika količina biljne mase u obliku ostataka rezidbe. Rezidbe se može obavljati na više načina što je uslovljeno veličinom zasada i raspoloživim tehničkim sredstvima. Nastala masa najpre predstavlja balast koji ometa prolazak zasadom sa druge strane je značajan energetski izvor. Energija iz te masi se može transformisati na više načina uz primenu odgovarajućih postupaka ili da se varati zemljištu postupkom mulčovanja. Kod zastarelih tehnologija upotrebe uglavnom se obavlja sakupljanje i sagorevanje ostataka rezidbe neposredno u zasadu, ili se vrši njihovo sitnjenje a zatim zaoravanje. Ovim postupcima ostaci rezidbe u zasadima su izgubljeni kao energetski vredan i količinski značajan izvor toplotne energije. Definisanje optimalnih tehnologija i tehničkih rešenja prikupljanja, utovara, transporta i neposredne pripreme ostataka rezidbe voćaka i vinove loze za dobijanje energije, presudno utiče na energetsku efikasnost voćarske proizvodnje i predstavlja veoma aktuelni problem. Zbog neracionalnog raspolaganja energijom i ekstenzivnije proizvodnje, u našim uslovima, prikupljanje, obrada, priprema i korišćenje biljnih ostataka nisu našli širu primenu. Ostaci rezidbe kao obnovljivi izvor energije ima i prednost u tome što se najčešće nalaze na mestu potrošnje ili u njihovoj blizini. Najjednostavniji i najstariji način korišćenja ostataka rezidbe kao energenta u procesima sagorevanja i dobijanja toplote je kada se u neizmenjenom obliku obavi proces sagorevanja. Obzirom na kabastu formu koju karakteriše mala zapreminska masa, uslovljava veoma malu racionalnost u transportu kao i otežan utovar, istovar, skladištenje i samu upotrebu u gorionicima. Ekološki problemi i deficit fosilnih goriva nameću potrebu da se u našem okruženju posveti veća pažnja iznalaženju postupaka pripreme i korišćenju ostataka rezidbe u zasadima kao energetskog goriva. Ovaj problem aktualizuju i norme Evropske Unije koje propisuju kao obavezu proizvodnje električne energije iz obnovljivih izvora, kako bi se doprinelo rešavanju problema nedostatka ekološki čiste energije i doprinelo očuvanje životne sredine

Eksploatacioni parametri kombajna za ubiranje semenskog kukuruza

Maize is one of the most important crops and one of the most significant naturally renewable energy source, but also numerous very different products. The maize seed production is much more complex, sensitive and expense than the commercial maize production. Therefore a special attention should be paid during the whole process of the seed production, in order to achieve higher yields and better seed quality. The aim of this study was to reveal the effects of harvest methods on maize hybrid seed production and on losses. Paper presents comparison of different technological designs of maize seed harvesters.Kukuruz je jedna od najznačajnijih gajenih biljaka i jedan od najznačajnijih prirodno obnovljivih izvora energije i velikog broja proizvoda. Proizvodnja semena kukuruza je veoma složena, osetljiva i znatno skuplja od merkantilne proizvodnje. Zbog toga se ovoj proizvodnji posvećuje posebna pažnja u cilju ostvarivanja većih prinosa i kvalitetnijeg semena. Cilj rada je da se pokaže kako načini ubiranja utiču na proizvodnju hibridnog semena kukuruza kao i na gubitke. Prikazana su različita tehnološka rešenja kombajna za ubiranje semenskog kukuruza

Operacionalizacija ekonomičnosti potrošnje goriva traktora

Fuel consumption in agriculture is on very high level. Even a small percentage of lowering fuel consumption can contribute to more successful management of agricultural enterprises. Reduced fuel consumption will, also, be a mean of fossil fuel resources preservation and ecology friendlier agriculture production. There are known methods for reducing fuel consumption abut are not fully used. This paper presents results of using known methods in operationalisation of fuel consumption economy. The results are given for tractors with diesel motors and common fuel supply systems.Poljoprivreda je veliki potrošač dizel goriva pa bi i malo procentualno smanjenje značilo veliku uštedu. To bi vodilo ka uspešnijem poslovanju poljoprivrednih preduzeća ali još značajnije je da bi se time doprinelo očuvanju ograničenih resursa fosilnih goriva kao i smanjenju zagađenja okoline. Metode za smanjenje potrošnje goriva su uglavnom poznate ali se nedovoljno primenjuju. Zbog toga se u ovom radu kroz plansku primenu poznatih metoda operacionalizuje ekonomičnost potrošnje goriva kod traktora sa dizel motorima koji imaju klasičan sistem snabdevanja gorivom

Dijagnostika sredstava mehanizacije mašinskih prstenova

The economical functioning of machinery rings is based on maximizing use of labor resources of machinery rings. This includes adequate logistical support. Maintenance of machinery and technical equipment of the ring is one of the most challenging logistical tasks within it is very important segment of the diagnostics.Ekonomično funkcionisanje mašinskih prstenova se zasniva na maksimiziranju korišćenja radnih resursa mašina prstena. To podrazumeva odgovarajuću logističku podršku. Održavanje tehničkih sredstava mašinskog prstena je jedan od najzahtevnijih logističkih zadataka u okviru koga je segment dijagnostike veoma značajan

Održavanje i analiza strukture zemljišta

The structure of land is one of their most important characteristics. Substantially influence the structure of the many features and processes in the soil is generally accepted. Soil aggregates are strongly influenced by human activities, including land use, tillage, application of manure and growing crops. Size of aggregates and their stability are interconnected to describe soil structure. Size distribution and aggregate stability after the break, are used to calculate quantitative stability index. In the classical approach to statistical analysis of soil structure are used: Gaussian normal function, and log-normal, Rosin-Rammler and Gaudin's-Schuhmann's functions. In addition to these distribution models recently introduced models are based on a dimensionless statistical moments and the log-hyperbolic distribution.Uticaj strukture zemljišta na osobine i procese u zemljištu je opšte prihvaćen. Zemljišni agregati su izloženi raznim uticajima, uključujući korišćenje zemljišta, obradu, aplikaciju stajnjaka i gajenje useva. Veličine agregata i njihova stabilnost međusobno su povezani. Stoga se raspodele veličina i stabilnost agregata, posle razbijanja, koriste za izračunavanje kvantitativnih indeksa stabilnosti. Klasična statistička analiza strukture zemljišta se oslanja na: normalnu, log-normalnu, Rosin- Rammler-ovu i Gaudin-Schuhmann-ovu funkciju raspodele. Pored navedenih, u novije vreme uvedeni su i modeli zasnovani na primeni viših statističkih momenata i hiperboličke raspodele

Tečni stajnjak kao potencijal stočarskih farmi u sistemu kogeneracije

Biomass is specific energetic resource, because of a possibility of getting heat, electricity, fuel etc. This kind of energy contribute to higher labour employment, reduce emission of SO2, CO2, NO2, comparing to other fossile fuels. In order to increase energetic efficiency of its production, optimal technology and adequate technical solutions for biomass using, are determined. Because of extensive production in our country, processes like gathering, treatment, preparing and using of biomass vaste are not in common use. This paper examines the state of the fattening farm's biomass as potential in cogeneration system, the same of renewable energy sources technologies. There are some experiances in countries with undeveloped livestock production, that redirected production process to better use of secondary products can significantly improve economic effects.Biomasa uopšte, a tečni stajnjak posebno, predstavlja raznorodni energetski izvor, jer se od njega može dobiti toplota, električna struja, gorivo za pogon i dr. Energija iz tečnog stajnjaka doprinosi većoj zaštiti životne sredine jer se, smanjuju emisije sumpor-dioksida, ugljen-dioksida i azot-dioksida, u odnosu na sagorevanje fosilnih goriva. Određena je optimalna tehnologija i tehnička rešenja korišćenja biomase iz stočarske proizvodnje, radi poboljšanja energetske efikasnosti proizvodnje. Postupci prikupljanja, obrade, pripreme, kao i korišćenja biomase, u našim uslovima nisu naišli na širu primenu, zbog ekstenzivnog načina proizvodnje i nedomaćinskog načina poslovanja. U radu je dato stanje biomase na stočarskim farmama, kao potencijala u sistemu kogeneracije, jednoj od tehnologija korišćenja obnovljivih izvora energije. Ekonomski efekti u zemljama sa manje razvijenom stočarskom proizvodnjom ukazuju da se tom pitanju mora posvetiti adekvatna pažnja i pravilno usmeriti proizvodnja, koja sa svojim sekundarnim proizvodima može doprineti pozitivnijem rezultatu