Search

Autonomous modular system mounted on a conventional (CON) sprayer operating on the principle of pulse-width modulation (PWM) control of electromagnetic valves represents state-of-the-art technology for implementation controlled application of spray mixture without changing the operating parameters of the sprayer (e.g. spray pressure, nozzle size). In accordance with the principles of precision viticulture, the pulse width modulation control is the primary technology, which allows the application of the required amount of spray mixture exclusively to the target areas of the vine without changing the droplet size spectrum and allows for even deposit quality and reducing the drift outside the target areas. In the vineyard, we tested an autonomous axial sprayer prototype throughout the entire spraying season in 2021 on which we have installed an autonomous modular system with enabled pulse-width control. We tested two modes of operation of the sprayer prototype, namely autonomous (continuous duty cycle control (DC: 0 to 100%)) and conventional (nozzle fully open at all time), at a steady spray speed of 6 kmh-1. We compared the amount of PPP expressed as a percentage between autonomous and conventional mode of operation of the sprayer through individual nozzles on the sprayer. The maximum saving of the spray mixture of 69.8%, through an individual nozzle was measured at phenological stage of the vine BBCH 55. A comparative analysis between the CON and PWM mode of the spray mixture application showed that we saved 626.24 l per year in the automated mode of operation., Autonomni modularni sustav postavljen na konvencionalnu (CON) prskalicu, koji operira na principu kontrole elektromagnetskih ventila modulacijom širine impulsa (PWM), predstavlja najsuvremeniju tehnologiju za provedbu kontrolirane primjene mješavine za prskanje bez promjene operativnih parametara prskalice (npr. pritisak prskanja, veličina mlaznice). U skladu s principima precizne vitikulture, kontrola modulacijom širine impulsa je primarna tehnologija, koja omogućava primjenu potrebne količine mješavine za prskanje isključivo na ciljana područja vinove loze, bez mijenjanja spektra veličine kapi, te omogućava ujednačenu kvalitetu nanosa i smanjenje zanošenja van ciljanih područja. U vinogradu je kroz cijelu sezonu prskanja u 2021. testiran prototip autonomne aksijalne prskalice, na koji je bio instaliran autonomni modularni sustav s omogućenom kontrolom širine impulsa. Testirana su dva načina rada prototipa prskalice, autonomni (kontinuirana kontrola radnog ciklusa (DC: 0 to 100%)) i konvencionalni (mlaznica potpuno otvorena sve vrijeme), pri standardnoj brzini prskanja od 6 kmh-1. Usporedili smo količinu sredstva za zaštitu bilja izraženu kao postotak između autonomnog i konvencionalnog načina rada prskalice kroz individualne mlaznice prskalice. Maksimalna ušteda mješavine za prskanje od 69,8%, kroz individualnu mlaznicu izmjerena je u fenološkoj fazi vinove loze BBCH 55. Komparativna analiza između CON i PWM načina primjene mješavine za prskanje pokazala je da je s automatiziranim načinom rada u godinu dana ušteđeno 626,24 L.

This paper describes a computer vision system based on image processing and machine learning techniques which was implemented for automatic assessment of the tomato seed germination rate. The entire system was built using open source applications Image J, Weka and their public Java classes and linked by our specially developed code. After object detection, we applied artificial neural networks (ANN), which was able to correctly classify 95.44% of germinated seeds of tomato (Solanum lycopersicum L.). Članek opisuje sistem računalniškega vida, ki temelji na tehnikah obdelave slik in strojnega učenja, ki je bil izdelan za avtomatsko oceno stopnje kaljenja semen paradižnika. Celoten sistem je bil zgrajen s pomočjo odprtokodnih aplikacij ImageJ, Weka in njihovih javno dostopnih javanskih kod, ki smo jih povezali v lastno originalno razvito kodo. Po odkrivanju predmetov na RGB slikah, smo uporabili umetne nevronske mreže (ANN), ki so bile sposobne pravilno razvrstiti 95,44% nakaljenih semen paradižnika (Solanum lycopersicum L.).

Monografija je namenjena kmetijskim svetovalcem in izobraževanju pridelovalcev o sodobnih načinih obdelave tal na vodovarstvenih območjih (VVO), ki obsegajo območje varovanja vodnjaka (VVO), zasilno zaščitno cono (VVO III), pomembno območje za podtalnico (VVO II) in zelo občutljivo območje (VVO I). Pripravili smo jo za potrebe izvajanja projekta SI-MUR-AT v okviru EU programa sodelovanja Interreg Slovenija-Avstrija 2014 – 2020. VVO predstavlja področja zajemanja pitne vode (vključno z vodo iz jezer, rek in podzemnih vodonosnikov), ki jih ščitimo pred prekomerno uporabo in kontaminacijo. Ker je VVO po navadi del kmetijske krajine, na kakovost vode lahko vplivajo nepravilne kmetijske prakse. V prvem delu monografije so predstavljene najpomembnejše omejitev konvencionalnega gojenja na VVO, zlasti obdelava tal, ki je omejena z lokalno in državno zakonodajo. Pomemben del monografije je predstavitev ohranitvenega kmetijstva, pri čemer je posebej opisana konzervacijska (ohranitvena) obdelava (KO), ki je edini sprejemljiv način priprave tal za setev na VVO. Poleg KO-sistemov so prikazani principi direktne setve brez mehanskega mešanja tla, setev v trakove in združene setve. The monograph was prepared to educate agricultural advisors and farmers on the modern ways of soil tillage at water protection zones (WPZ), comprising of wellhead protection area, intake protection zone, significant groundwater recharge area and highly vulnerable area. It was prepared for the project SI-MUR-AT, an EU Cooperation Program INTERREG Slovenia-Austria 2014 – 2020. WPZ represents source water (including water from lakes, rivers and underground aquifers) protection from overuse and contamination. Since WPZ is usually the part of agricultural landscape, the water quality might be affected by the improper agricultural practices. In the first part the most important regulation on the way of conventional farming, especially soil tillage, fertilization is described as suggested by local and state legislative. The major part is contributed to the conservation agriculture (CA), whereby the conservation tillage (CT) represents the only acceptable way of preparing the soil for sowing. Beside CT systems no or minimum mechanical soil disturbance, organic mulch soil cover, and crop species diversification is presented in this monograph.

This research demonstrates the basic elements of a prototype automated orchard sprayer which delivers pesticide spray selectively with respect to the characteristics of the targets. The density of an apple tree canopy was detected by PROWAVE 400EP250 ultrasound sensors controlled by a Cypress PSOC CY8C29466 microcontroller. The ultrasound signal was processed with an embedded computer built around a LPC1343 microcontroller and fed in real time to electro-magnetic valves which open/close spraying nozzles in relation to the canopy structure. The analysis focuses on the detection of appropriate thresholds on 15 cm ultrasound bands, which correspond to maximal response to tree density, and this was selected for accurate spraying guidance. Evaluationof the system was performed in an apple orchard by detecting deposits of tartrazine dye (TD) on apple leaves. The employment of programmable microcontrollers and electro-magnetic valves decreased the amountof spray delivered by up to 48.15%. In contrast, the reduction of TD wasonly up to 37.7% at some positions within the tree crown and 65.1% in the gaps between trees. For all these reasons, this concept of precise orchard spraying can contribute to a reduction of costs and environmental pollution, while obtaining similar or even better leaf deposits.

Early information on yield has a special importance in the intensive apple production. Since the majority of older forecast methods are labor, time, organization and cost intensive a hybrid model based on image analysis and neural network was developed. From the end of fruit thinning in June till harvesting digital images of 120 trees of yellow-skin ‘Golden Delicious’ (four times) and 120 trees of red-skin ‘Braeburn’ (five times) were captured from intensive orchards. Firstly, each image was processed by image analysis algorithm to receive the data on number of fruits and a yield forecast, for each sampling period separately, which served as the input information for modeling the yield with the artificial neural network (ANN). The forecast of the hybrid method showed a higher accuracy than the image analysis for both varieties, since the new procedure managed to increase the correlation between the forecasted and weighed yield from 0.73 to 0.83 for ‘Golden Delicious’ and from 0.51 to 0.78 for ‘Braeburn’. The standard deviation/image was decreased from 4.79 to 2.83 kg for ‘Golden Delicious’ and from 3.64 to 2.55 kg for ‘Braeburn’. To introduce the new method in practice, additional tests on various locations including all important apple varieties are recommended.

Diplomsko delo zajema konstruiranje in vzdrževanje delovnih priprav v kovinarskopredelovalni industriji. Priprave so za proizvodnjo zelo pomembne, predvsem pri serijskih proizvodih. Zagotavljajo nam ponovljivost in natančnost pri sestavi in manipulacijah z izdelki. Za različne operacije v delovnih procesih se uporabljajo temu primerno namensko snovane delovne priprave. S pomočjo delovnih priprav se znatno skrajša proizvodni čas in poviša kvaliteta izdelave, kar v končni fazi pomeni konkurenčnost na trgu in krajše dobavne roke. Za sistematično delo načrtovanja in koncipiranja priprav so upoštevane smernice po VDI 2221. Preučene so tudi različne vrste vzdrževanja. Po končanem projektu je bila izdelana analiza pripravnih in izdelovalnih časov pred in po uporabi novih delovnih priprav, kar je pokazalo za smiselno uporabo priprav in upravičenost investicije. Splošno so predstavljene priprave, ki se uporabljajo v kovinarskopredelovalni industriji, in čemu služijo. Design and maintenance of working jigs in metalwork manufacturing industry are the main topics of the diploma work. Jigs are very important for the production process, especially with mass production. They provide repeatability and accuracy during assembly and manipulation with products. For various operations in work processes different jigs are used, which are designed especially for those specific operations. With the help of working jigs time of production process is extremely shortened and the quality of production is increased. This ultimately brings competitiveness in the market and shortens delivery times. Guidelines given by VDI 2221 are followed in the work to achieve systematic work of planning and conceptual design of jigs. Various types of maintenance are also studied. At the end of the work some analyses of preparation and production time before and after the usage of new working jigs are presented. The results showed that it is reasonable to use jigs and to invest into them. General survey of jigs used in the metalwork manufacturing industry and their application is presented in the work.

The paper describes a thermal imaging based technique for estimating number, diameter and yield of apple fruits automatically under natural condition in the orchard. A thermal camera was mounted on a tool-frame tractor equipped with a PC for acquiring apple trees images four times during the vegetation period June-September 2002. Each time twenty apple trees were recorded from both sides of the row. Video signals from the camera were digitised using frame grabber and the images were processed off-line using several image processing algorithms. Correlation coefficients (R-2 from 0, 78 to 0, 81) were established between manually measured fruit number and estimated number based on the thermal imaging algorithm. For measuring the fruit's diameter R-2 between 0, 56 and 0, 65 were established and were slightly increasing according to the size development during the ripening. The R-2 for current yield per tree were estimated from 0, 69 to 0, 79 when manual measurements were compared to thermal imaging.

The paper presents an example of the determination of stress and a dampening tree-stage spur gear assembly. 2nd order Lagrange equations are used for mathematical description of the model. The damping factor obtained from previous research into simple gear pairs was used in the computational simulation of a three-stage spur gear assembly. This simulation provides the estimation of actual maximum dynamic forces acting upon gear teeth, which are then compared with the results of experimental measurements on the equivalent operational gear assembly. The results of the proposed numerical dynamic analysis in form of the actual internal dynamic forces acting upon the teeth can be used for strength analysis of gear teeth already at the design stage of the gear assembly, which is much cheaper and faster than expensive experimental testing on dedicated prototypes.

Na nogometnih igriščih je zelo pomembno, da je travna ruša odporna na obremenitve, ki jih predstavljajo tekme na najvišjih nivojih različnih tekmovanj. Da lahko to dosežemo, je zelo pomembno, da se na igriščih izvajajo agrotehnični ukrepi: košnja, zračenje, škropljenje, zalivanje in gnojenje, ki travni ruši omogočajo optimalne pogoje za rast, igralcem pa optimalne pogoje za igro. Na stadionu »Ljudski vrt« v Mariboru so se leta 2018 odločili za zamenjavo travne ruše, da bi igralcem zagotovili optimalne pogoje za igro. V magistrskem delu smo želeli z merjenji števila posameznega agrotehničnega ukrepa in merjenjem parametrov porabe goriva, časa in hitrosti ugotoviti, ali z zamenjavo travne ruše lahko zmanjšamo potrebo po tehnoloških ukrepih na stadionih, ki so opremljeni z najsodobnejšo travno rušo. It is very important for football that the surface is resistant to the burdens during matches and different competitions. In order to achieve this, it is very important that the following agro-technical measures are carried out on the fields: mowing, ventilation, spraying, watering and fertilization. If grasses are provided with optimal conditions for growth, the players are provided with optimal conditions for the game. That is why, in 2018 in Maribor, at the »Ljudski vrt« stadium, they decided to replace the grass surface in order to provide the players with optimal conditions for the game. The goal of the master's thesis was to determine, by measuring the number of individual agrotechnical measurements and measuring the fuel, time and speed parameters of parameters, or by replacing the grass surface, if the need for technological measures in the stadiums equipped with the most modern grassland could be reduced.

Za potrebe intenzivne pridelave hrane se vedno več rastlin goji v zavarovanih prostorih, kjer so rastline zaščitene pred neželenimi vremenskimi vplivi. Zavarovani prostori so lahko povsem enostavni objekti pokriti z različnimi folijami ali pa najsodobnejši steklenjaki z avtomatskim uravnavanjem klime. V letu 2017 smo na domači njivi na Pobrežju postavili štiri nizke tunele in jih prekrili z različnimi prekrivkami, in sicer z PE folijo debeline 60 µm in 150 µm, z PE folijo debeline 60 µm, ki je bila naluknjana in z 19 g PP folijo oziroma kopreno. V obdobju od 20. 4. 2017 do 18. 5. 2017 smo z dataloggerjem CR1000 podjetja Campbell Scientific konstantno merili zunanjo temperaturo in temperaturo v tunelih. Kot najprimernejša prekrivka se je izkazala koprena, saj je rastlinam nudila višje temperature ponoči, podnevi pa se v tunelih ni segrelo preveč. Kot neprimerni za prekrivanje nizkih tunelov sta se izkazali PE foliji debelin 150 in 60 µm, saj se je že ob zunanjih temperaturah nad 10 °C v njih ogrelo preko 40°C. Za poskusno rastlino smo v tunele posadili sadike nizkega fižola, vendar jih je že v prvi noči merjenja skoraj v celoti uničila zunanja temperatura -4,2°C. For the needs of more intensive food production, more and more plants are grown in protected areas, where the plants are also protected from adverse weather effects. Protected areas can be simple objects covered with different foils or state-of-the-art glass bottles with automatic climate control. In 2017, four low tunnels were erected on a home field in Pobrežje and covered with different overlays, namely PE film with a thickness of 150 μm and 60 μm, PE film with a thickness of 60 μm, which was punched, and with 19 g PP film or agryl. In the period from April 20, 2017 to May 18, 2017, Campbell Scientific's CR1000 datalogger constantly measured the outside temperature and the temperature in the tunnels. The agryl was the most appropriate cover, providing plants with higher temperatures at night and did not warm the tunnels too much during the day. PE films of 150 and 60 µm thicknesses, proved to be unsuitable for covering low tunnels, since they already heated above 40 °C at outdoor temperatures of above 10 °C. Low bean seedlings were planted in the tunnels as the test plant, but were almost completely destroyed by -4.2 ° C on the first night of measurement.