Ekonomska efikasnost investicija u proizvodnji mleka na porodičnim gazdinstvima

Dairy production in Republic of Serbia is conducted primarily at family farms. However, these farms mostly posses small number of cows, so that they are not capable to apply modern technical and technological solutions concerning housing and feeding of cows. Small family farms can not purchase contemporary milking equipment; thus, they have no possibility to produce high quality milk. Therefore it is necessary to direct towards formation of large family dairy farms. Consequently, it is needed to provide sources of financing for very high investments, which are indispensable. To determine whether investments in dairy production at large family farms are economically efficient and financially feasible, appropriate model of family farm has been formed. This model was used to apply dynamical methods of investment evaluation, such as Net Present Value, Internal Rate of Return and Payoff method. It is determined that investing in large family dairy farms is economically efficient, as well as financially feasible.Proizvodnja mleka u Srbiji odvija se prvenstveno na porodičnim poljoprivrednim gazdinstvima. Međutim, ova gazdinstva većinom poseduju mali broj krava, pa nisu u mogućnosti da primenjuju moderna tehnička i tehnološka rešenja u smeštaju i ishrani krava. Mala porodična gazdinstva ne mogu nabaviti savremene muzne uređaje, pa su zato onemogućena da proizvode mleko visokog kvaliteta. Zbog toga treba ići prema formiranju krupnih porodičnih gazdinstava za proizvodnju mleka. U tom cilju potrebno je obezbediti izvore finansiranja za veoma visoka investiciona ulaganja, koja su neophodna. Da bi se utvrdilo da li su ulaganja u proizvodnju mleka na krupnim porodičnim gazdinstvima ekonomski opravdana i finansijski prihvatljiva, formiran je odgovarajući model porodičnog gazdinstva. Na njemu su primenjene metode dinamičke ocene investicija, kao što su neto sadašnja vrednost, interna kamatna stopa i rok povraćaja. Utvrđeno je da je investiranje u krupna porodična gazdinstva za proizvodnju mleka ekonomski opravdano, kao i finansijski prihvatljivo

Procena vrednosti objekata za čuvanje stočne hrane

In order to keep milk production economically effective in contemporary business environment, it is necessary to use appropriate types and combinations of animal feed. This means that the bulky part of the meal for the cows has to be based on the use of corn silage, with the addition of small amounts of alfalfa hay. This combination of forage allows for high milk production per cow, while keeping production costs low. However, this concept of nutrition is related to high investments in appropriate facilities for the storage of animal feed. To evaluate the economic effectiveness of investments in modern feed storages, a method of present value of investment is used. Determined present value of investment is compared with the corresponding construction costs of the objects at different prices of animal feed and various assumed losses due to its inadequate storage.Da bi u savremenim uslovima poslovanja proizvodnja mleka bila ekonomski opravdana, neophodno je koristiti odgovarajuće vrste i kombinacije stočnih hraniva. To znači da se kabasti deo obroka za krave mora zasnivati na korišćenju kukuruzne silaže, uz dodatak manje količine sena lucerke. Ovakva kombinacija kabastih hraniva omogućava visoku proizvodnju mleka po kravi, uz održavanje troškova proizvodnje na niskom nivou. Međutim, navedeni koncept ishrane vezan je za visoka investiciona ulaganja u odgovarajuće objekte za smeštaj stočne hrane. Da bi se utvrdila ekonomska efektivnost investicionih ulaganja u moderne objekte za čuvanje stočne hrane, korišćena je metoda prinosne vrednosti investicije. Utvrđena prinosna vrednost poređena je sa odgovarajućim troškovima izgradnje navedenih objekata, pri različitim cenama stočne hrane i različitim pretpostavljenim gubicima usled njenog neadekvatnog skladištenja

Primena metoda ekvivalenta sigurnosti za ocenu rizika investiranja u proizvodnji mleka na porodičnim gazdinstvima

Bearers of cattle production in Serbia are small family farms. Such farms should change significantly their business operations in order to be competitive and to enable existence in future. That implies cattle breading in modern barns, use of modern equipment and nutrition improvement. However, to achieve such goal significant investments are needed. The most common production type at Serbian family farms is combination of milk, heifers and steers production. Comparing to other cattle production types, this production type requires very high investments. At the same time, such investments are connected to significant risks. The risks are caused by fluctuations of milk price, steer price, fodder costs etc. To evaluate economic effectiveness of investments in above mentioned farm type, on appropriate model were applied dynamical methods for investment evaluation. In addition, financial feasibility of investment was examined, assuming the most unfavorable financing conditions. To evaluate economic effectiveness of investment in risky circumstances, certainty equivalent method has been used. This method is not prominent and adequately used in our scientific and professional practice.Nosioci govedarske proizvodnje u Srbiji su sitna porodična gazdinstva. Da bi ova gazdinstva u budućnosti opstala i bila konkurentna, ona moraju uvesti značajne izmene u svoje poslovanje. To podrazumeva držanje goveda u modernim objektima, korišćenje savremene opreme i poboljšanje načina ishrane. Međutim, da bi se to ostvarilo neophodna su značajna investiciona ulaganja. U Srbiji je na porodičnim gazdinstvima najviše zastupljen tip proizvodnje koji podrazumeva kombinaciju proizvodnje mlijeka, junica i tovne junadi. U poređenju sa ostalim tipovima govedarske proizvodnje, ovaj tip proizvodnje zahteva veoma visoka investiciona ulaganja. Istovremeno, ovakva su ulaganja vezana sa značajnim rizicima, koji su izazvani variranjem cene mleka, cena tovne junadi, troškova stočne hrane i sl. Da bi se ispitala ekonomska efektivnost ulaganja u navedeni tip farmi, na odgovarajućem modelu su primenjene dinamičke metode za ocenu investicija. Pored toga ispitana je i finansijska prihvatljivost investicije, pod pretpostavkom najnepovoljnijih uslova finansiranja. Za ocenu ekonomske efektivnosti investicije u uslovima rizika primenjen je metod ekvivalenta sigurnosti, koji nije dovoljno poznat i korišćen u našoj naučnoj i stručnoj praksi

Multiple Single-Unit Long-Term Tracking on Organotypic Hippocampal Slices Using High-Density Microelectrode Arrays

A novel system to cultivate and record from organotypic brain slices directly on high-density microelectrode arrays (HD-MEA) was developed. This system allows for continuous recording of electrical activity of specific individual neurons at high spatial resolution while monitoring at the same time, neuronal network activity. For the first time, the electrical activity patterns of single neurons and the corresponding neuronal network in an organotypic hippocampal slice culture were studied during several consecutive weeks at daily intervals. An unsupervised iterative spike-sorting algorithm, based on PCA and k-means clustering, was developed to assign the activities to the single units. Spike-triggered average extracellular waveforms of an action potential recorded across neighboring electrodes, termed ‘footprints’ of single-units were generated and tracked over weeks. The developed system offers the potential to study chronic impacts of drugs or genetic modifications on individual neurons in slice preparations over extended times

Uređenje, korišćenje i mere zaštite poljoprivrednog zemljišta opštine Kosjerić

The Kosjerić municipality is located in the north of the Zlatiborski region and total land area is 456.7 km2 Lower quality soils types and subtypes take the biggest area in the municipality. Loamy sand and sandy loam soils prevail in highland area of municipality. There are vertisol and eutric cambisol on lower terrain. Alluvial soils are under maize, vegetable and meadows, while slight slopes are under cereals, orchards and pastures. On the hilly part of terrain fruit production is traditionally developed. Analysis of the agricultural lands shows that plum orchards are ruined and old, so that renewal is needed. Higher mountainous parts are under forests where beech and oak prevails. Forest area takes 23878 ha (2/3 of total municipality area). Properties and varieties of soils on the Kosjeric municipality territory demand application of complex reclamation measures. These measures should solve range of complex problems, but it takes time and capital goods. Possible positive results of arrangement, agricultural soil usage and protection in Kosjeric municipality are multiple: soil conversion from agricultural to other can not be hold up, but it can be realised with carefully chosen restrictive practices. In western and eastern part of municipality should take up sustainable development principles. To establish forests as much as possible for the purpose of increasing environmental value, economic benefit and protection from erosion and strong current on slopes. Unfortunatelly Titan cement factory is not possible relocate, altought it`s position is upstream from town Kosjeric. There is possibility to apply range of suitable protective measures thus considerably improve existing properties of soils and environment.Opština Kosjerić je najsevernija opština Zlatiborskog okruga, u zapadnom delu Srbije, i ima 359 km². Najveće površine u opštini zauzimaju manje kvalitetni tipovi i poditopovi zemljišta. U brdsko-planinskom delu opštine preovlađuju zemljišta koja prema mehaničkom sastavu predstavljaju ilovaste peskuše i peskovite ilovače. Na nižim terenima se nalaze smonice i gajnjače. Aluvijalne zaravni su pod kukuruzom, povrćem i livadama, a blage padine su pod kulturama žita, voćnjaka i sa pašnjacima. Na brežuljkastom delu je tradicionalno razvijeno voćarstvo. Istraživanja na terenu ukazuju da su šljivici, uglavnom, propali i stari, i da ih treba postepeno obnoviti. Viši planinski delovi su pod šumom u kojoj preovađuju bukva i hrast. Površine pod šumama iznose 23878 ha (2/3 od ukupne površine opštine). Osobine i raznovrsnost zemljišta na prostoru opštine Kosjerić zahtevaju primenu kompleksnih melirativnih mera, koje treba da reše niz složenih, postojećih problema, ali zašto je potrebno vreme i znatna materijalna sredstva. Mogući pozitivni rezultati uređenja, korišćenja i zaštite poljoprivrednog zemljišta Opštine Kosjerić su mnogobrojni, od kojih su najvažniji: Konverzija namene poljoprivrednog u drugo zemljište se ne može zaustaviti, ali se može realizovati uz pažljive restriktivne mere . U zapadnom i istočnom delu Opštine, treba sprovoditi aktivno principe održivog razvoja, u pogledu korišćenja zemljišta zasnivati što više šume, zbog ambijentalnih i ekoloških vrednosti, ekonomske koristi i zaštite od erozije i bujica usled nepovoljnih nagiba terena; Nažalost, cementaru -Titan nije moguće izmestiti, iako se nalazi uzvodno od gradskog naselja Kosjerić, ali je moguće primeniti niz adekvatnih zaštitnih mera i znatno poboljšati postojeću situaciju, prema zemljištu i okolini

Dizajn, klasifikacija, perspektiva i moguća aplikacija dronova u poljoprivredu Srbije

The paper analyzes the possibility and the needs for the use of specific types of robots (mini unmanned aircraft with different designs and the designation of UAVs) and the possibility of using in agriculture (agrodrone). The year 2015 was proclaimed (Fortune Magazine, 2016) as the year of increasing and widespread use of UAVs in various areas of human activity, especially in agriculture and forestry (75% of use). This is important for large farm areas, where UAV has many useful functions and a very cost-effective commercial application. Today, the needs for UAVs have increased sharply with various opportunities for both civilian and military needs. There is also a significant interest in the development of new drones that can autonomously fly in different environments and locations and can perform various missions and tasks. Over the past decade, a wide range of applications for drones has gained the significance that led to the discovery of various types of unmanned UAVs of different sizes and weights. In this review, the classification of UAVs ranging based on a detailed overview of the development of the drone industry in recent years, this paper demonstrates the evolution of drones and differents application technologies. Of course, this development is very advanced and revolutionary, as well as the development of mobile and smart phones and the Internet, which will open the way for many users to participate in defining the future of UAV implementation. LIVONA Company, Belgrade, Serbia (and Institute of Agricultural Engineering, Faculty of Agriculture in Belgrade, in tehnical cooperation) has a study and plans on the implementation of the model micro drone EBee SQ Livona RTK in the future general plans for inspection of protection Soils of territory Minicipality of Stara Pazova (351 km2), and agricultural company Napredak , and exspecially plans for soils of agriculture of R. Serbia. VEKOM GeoCompany from Belgrade, (in cooperation with Institute of Agricultural Engineering, Faculty of Agriculture in Belgrade), has a study and plans on the implementation of the model of the drone Aibot KX6 model, in the future of application of agricultural soils of region Open pit Kolubara for area from app. 600 km2 and the other soils of Region). Institute of Agricultural Engineering, Faculty of Agriculture in Belgrade, in cooperation with Municipality of Ub, has a study and plans on the implementation of the model micro drone Hubsan H109S X4 PRO in the future plans general inspection of protection Soils and Waters of territory of Municipality Ub (456 km2).U radu su analizirane mogućnosti i potrebe upotrebe specifičnih vrsta robota (mini bespilotnih letelica sa različitim dizajnom, označane kao UAV) i način korištenja u poljoprivredi (agrodron). Časopis Fortune je 2015.godinu proglasio kao godinu sve većeg i široko rasprostranjene upotrbe UAV letelica, u različitim oblastima ljudske delatnosti, posebno u poljoprivredi i šumarstvu (75% upotrebe). Ovo je naročito važno za velike farme i oblasti pod šumama, gde UAV ima mnogo korisnih funkcija i veoma isplative komercijalne aplikacije. Danas, potrebe za UAV imaju nagli porast sa različitim mogućnostima kako za civilne tako i za vojne potrebe. Takođe postoji značajan interes za razvoj novih bespilotnih letelica koji mogu autonomno leteti u različitim okruženjima i lokacijama i obaviti različite misije i zadatke. Tokom protekle decenije XXI veka, širok spektar aplikacija za bespilotne letelice je dobio značaj koji je doveo do konstrukcija različitih tipova bespilotnih UAV, različitih veličina i težina i svakako namene. Naravno, tehnološki razvoj kod dron sistema je veoma tehničko-tehnološki napredan i revolucionaran, uz razvoj mobilnih i pametnih (android) telefona i interneta, brzo otvora puteve i mogućnosti za mnoge korisnike u definisanju nove budućnosti implementacije UAV u različitim oblastima primene . Kompanija Livona d.o.o., Beograd i Institut za poljoprivrednu tehniku, Poljoprivredni fakultet u Beogradu, u tehničkoj saradnji imaju planove o implementaciji modela mikro drona EBee SK Livona RTK u narednim generalnim planovima za inspekciju, zaštitu i korišćenje poljoprivrednih zemljišta Republike Srbije, i posebno teritorije Opštine Stara Pazova (351 km2), gde je posebno mesto poljoprivrednog preduzeća Napredak a.d. VekomGeo d.o.o, Beograd u saradnji sa Institutom za poljoprivrednu tehniku Poljoprivrednog fakulteta u Beogradu ima planove o budućoj upotrebi drona model Aibot X6, za nadzor na površinama od 600 km2 (i poljoprivredna zemljišta) otvorenog kopa R.B. Kolubara ili drugih objekata. Institut za poljoprivrednu tehniku, Poljoprivredni fakultet u Beogradu, ima planove o saradnji sa opštinom Ub, zbog upotrebe modela mikro drona Hubsan H109S Ks4 PRO u inspekciji oko zaštite i načina korišćenja zemljišta i voda na ovoj teritoriji (456 km2)

From selective stimulation to single-spike detection: interfacing neocortical neurons with thousands of microelectrodes at subcellular spatial resolution

Complex operations performed by neuronal networks arise from the orchestrated activities of individual neurons. Therefore, an experimental ability to simultaneously observe and elicit activity in individual neurons over extended periods of time is a prerequisite for exploring how neural circuits work. Recent advances in microelectronics and microfabrication technology have produced novel high-density microelectrode arrays (HD-MEAs) that enable measuring and stimulating in vitro neuronal activity across thousands of microelectrodes noninvasively. The arrays’ dense arrangements of microelectrodes provide hundreds of locations to comprehensively access the electrical activity of a single neuron. The microelectrodes can simultaneously observe and elicit activities in virtually any neuron within the network. However, selectively targeting a specific neuron and not its neighbors and extracting the small signals of a cell’s neurites from the background noise both pose difficult challenges that must be overcome. With this in mind, the first part of this thesis presents strategies for the electrical identification and selective stimulation of individual neurons within cortical networks. The second part describes a method for observing the small individual action potentials (APs), importantly without the need to average multiple events, emitted by the hundreds of micrometers long axonal arbors. The combination of these techniques enables precisely controlling and observing electrical activity across an entire neuron and, thereby, allows for influencing and monitoring how targeted neurons operate within the network. In the first project, we studied cultured neocortical neurons by using high-density microelectrode arrays and optical imaging, complemented by the patch-clamp technique, with the aim to correlate a neuron’s responsiveness to extracellular stimulation to the morphology and electrical characteristics of its various subcellular compartments. We developed strategies to electrically identify any neuron in the network, while subcellular-spatial-resolution recording of extracellular AP traces enabled their assignment to the axon initial segment (AIS), axonal arbor and proximal somatodendritic compartments. We proposed analytical approaches to reveal correlations between spatiotemporal features of extracellular APs and effective stimulation voltages, and explored the limits of targeted extracellular stimulation of different neuronal compartments. We found that stimulation at the AIS required low voltages and provided immediate, selective and reliable neuronal activation, whereas stimulation at the soma required high voltages and produced delayed and unreliable responses. Subthreshold stimulation at the soma depolarized the somatic membrane potential without eliciting APs. Approaches established in the first project were used to develop a method to non-invasively detect single action potentials throughout the whole axonal arbor of individual cortical neurons. The method was then used to measure (I) the precision of neuronal activation in response to extracellular stimulation; (II) the precision of AP propagation across multiple axonal branches; and (III) to observe changes in the precision and velocity of AP propagation during a high-frequency regime of neuronal activity. We found that (I) an increase in stimulation voltage magnitude decreases neuronal activation latency and, at the same time, increases temporal precision of the activation itself; (II) the precision of AP propagation decreases with the length of the propagation path; and (III) the high-frequency regime of neuronal activity decelerates AP propagation by 20.7 % and decreases the precision of AP propagation by 21.4 %

Functional imaging of conduction dynamics in cortical and spinal axons

Mammalian axons are specialized for transmitting action potentials to targets within the central and peripheral nervous system. A growing body of evidence suggests that, besides signal conduction, axons play essential roles in neural information processing, and their malfunctions are common hallmarks of neurodegenerative diseases. The technologies available to study axonal function and structure integrally limit the comprehension of axon neurobiology. High-density microelectrode arrays (HD-MEAs) allow for accessing axonal action potentials at high spatiotemporal resolution, but provide no insights on axonal morphology. Here, we demonstrate a method for electrical visualization of axonal morphologies based on extracellular action potentials recorded from cortical and motor neurons using HD-MEAs. The method enabled us to reconstruct up to 5-cm-long axonal arbors and directly monitor axonal conduction across thousands of recording sites. We reconstructed 1.86 m of cortical and spinal axons in total and found specific features in their structure and function