2018

Selle valdkonna püsiv URIhttp://hdl.handle.net/10492/5371

Sirvi

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3D image analysis of the shapes and dimensions of several tropical fruits
(2018) Herak, D.; Mizera, C.; Hrabe, P.; Kabutey, A.
T hree dimension virtual models of Avocado ( Persea americana ) , Salak ( Salacca zalacca ) , Dragon fruit ( Hylocereus undatus ) , Mango ( Mangifera indica ) , Coconut ( Cocos nucifera ) using 3D scanner Intel RealSense were determined. C alculated models based on arithmetic and geometric diameter were also determined. From statistically analysis implies that virtual models on significance level 0 .05 are significantly different with calculated values based on arithmetic or geometric diameter.
Additional concentrates do not affect feeding times of cows, but social positions of cows do
(2018) Soonberg, Maria; Kass, Marko; Kaart, Tanel; Leming, Ragnar; Arney, David R.; Estonian University of Life Sciences. Department of Animal Nutrition; Estonian University of Life Sciences. Department of Animal Breeding and Biotechnology
In robotic milking dairy systems lack of control over intakes can be problematic for balancing the forage and concentrate portions of diets. This can lead to proble ms associated with high concentrate intakes and concomitant low forage intakes. To check this as a problem, the feeding behaviour of cows was observed: the number of daily visits to the feed barrier, the duration of these visits and actual feeding, of high and low yielding cows. The cows were robot - milked and fed a ration comprising, separately, concentrate feed from a robot and a feeder, and a grass/clover silage mix forage at the feed barrier. Individual variation in visiting times and times spent at the feed barrier were greater than the effect of level of production. There was no evidence that cows with higher milk yields are differentially motivated to feed from forage. But more dominant cows spent more time feeding than submissive cows.
Agricultural field production in an ‘Industry 4.0’ concept
(2018) Jørgensen, M.H.
Precision Agriculture is a well-established concept in agricultural field production. It has developed over the last three decades. As part of this concept, farmers are used to collect and handle data. Farmers are also used to create solutions for field operations based on their knowledge of diversity and local data. When compared to classic industrial production, agricultural field operations interact with a biologically-active system. From a production management system point of view, industrial production takes place in close, well-defined environments in which performance data can, to a great extent, be measured by deterministic matters: mass (kg), volume/dimensions (m3 /m), time (sec), etc. In agricultural operations such as work involving tillage, seeding, fertilising, and plant care, there are by nature a good many possible adjustments available in order to optimise the operation method, plus intensity and timing. The challenge here is to establish the levels of knowledge that are necessary to support the control of the individual and/or graduated, precision-based operations. Within this context, parameters such as, for example, the workability of the soil cannot be defined in terms of a few deterministic parameters. Neither can the operational impact upon the soil which is made by the tools being used. It is assumed that this challenge is part of the reason why the concept of precision agriculture still contains a great deal of unutilised potential. The hypothesis raised by this article is that analysis should be carried out in regard to whether inspiration for the concept of an ‘Industry 4.0’ can facilitate the establishment of operational solutions in the field of precision farming.
Agricultural residues in Indonesia and Vietnam and their potential for direct combustion: with a focus on fruit processing and plantation crops
(2018) Brunerová, A.; Roubík, H.; Brožek, M.; Velebil, J.
Energy consumption in Indonesia and Vietnam has grown rapidly in recent decades. To meet the energy needs of both countries, a higher utilisation of waste biomass sources may represent an adequate solution. Investigated samples represent major crop residues (waste biomass) originating mainly from the agriculture sector of the selected countries. Herbaceous waste biomass from Indonesia is, namely, cassava stems and root peelings ( Manihot esculenta ), coffee leaves ( Coffea arabica ), cacao leaves ( Theobroma cacao ), banana leaves ( Musa acuminata ), bamboo leaves ( Bambusoideae spp.) and aloe vera leaves ( Aloe vera ). Furthermore, fruit and aquatic waste biomass originating from Vietnam is, specifically, sugarcane bagasse ( Saccharum officinarum ), durian peelings ( Durio zibethinus ), rambutan peelings ( Nephelium lappaceum ), banana peelings ( Musa acuminata ), water milfoil ( Myriophyllum spicatum ) and water hyacinth ( Eichhornia crassipes ). All mentioned types of waste biomass were subjected to proximate and calorimetric analysis: moisture, ash and volatile matter contents (%) and higher and lower heating values (MJ kg – 1 ). Obtained values indicated the highest level of ash content in fruit bioma ss samples in the case of sugarcane bagasse (0.84%), in herbaceous biomass in the case of cassava stems (3.14%) and in aquatic biomass in the case of water hyacinth (14.16%). The highest levels of lower heating values were achieved by following samples (be st samples from each biomass type): cassava stems (17.5 MJ kg – 1 ); banana peelings (17.3 MJ kg – 1 ) and water hyacinth (12.8 MJ kg – 1 ). The overall evaluation of all observed samples indicated that the best suitability for energy utilisation by direct combusti on of investigated representatives is fruit waste biomass, followed by herbaceous waste biomass and then aquatic waste biomass.
Agronomic evaluation of a Colombian passion fruit (Passiflora edulis Sims) germplasm collection
(2018) Galeano Mendoza, C.H.; Cerón-Souza, I.; Arango, L.V.
Passion fruit (Passiflora edulis Sims) is one of the most promissory crops in Colombia with approximately 7,400 ha cultivated, an average production of 89,000 t and an average yield of 15 t ha-1. However, low yields as well as harvest problems including fruit quality, generate important losses, mainly due to lack of improved cultivars with particular characteristics for each market (fresh consumption, agroindustry) and specific adaptations to biotic and abiotic stress factors in producer areas. Therefore, as a pre-breeding phase, this study aimed at characterizing preliminary the production and physiochemical characteristics of 60 passion fruit germplasm accessions maintained in Corporación Colombiana de Investigación Agropecuaria (AGROSAVIA). We cultivated these accessions in the field for 22 months between 2014 and 2015, measuring 17 variables associated to both yield production and fruit quality. We analysed data using phenetic and multivariate methods to establish levels of genetic diversity. Additionally, we constructed a selection index (SI) with the most informative variables to select individuals according to fruit weight, shape and colour, as well as juice percentage. Results of genetic grouping and principal components showed a broad genetic diversity across the working collection, without any population substructure. Fruit volume, pulp and seed weight were the variables that explained 80% of the phenotypic variation. Finally, we identified 30 promissory accessions as parental for the first cycle of recurrent selection using the SI. We conclude that this core collection represents the diversity included in the working collection with promissory accessions to initiate an intra-population recurrent selection program.
Air flow conditions in workspace of mulcher
(2018) Čedík, J.; Chyba, J.; Pexa, M.; Petrásek, S.; Jedelský, J.; Malý, M.
Currently, there has been a great effort on increasing the efficiency of agricultural machinery. The energy demands of mulching with the vertical axis of rotation depends on the amount of pr ocessed material per unit of time, its properties and efficiency of material processing. Another important factor that is affecting the overall energy demands is the energy losses, which can be even higher than energy, required for the processing of materi al. The efficiency of the material processing and the energy losses are influenced to a large extent by the air flow inside the mulcher workspace, which is created by the movement of working tools. The air flow ensures the repeated contact of the processed material with the working tools, affects the energy losses and the quality of work. The contribution deals with the air flow conditions inside the workspace of mulcher with the vertical axis of rotation. The velocity of the air flow was measured my means of LDA (Laser Doppler Anemometry) method in three planes above the surface (180, 100 and 20 mm ) and in two directions (peripheral and radial). The laboratory model of one mulcher rotor from mulcher MZ 6000 made by BEDNAR Ltd. company was used for the measu rement. From the results it is evident that the maximum values of peripheral velocity of the air flow reach approx. 50% of the velocity of the tools. In the radial plane an air vortex is created between 20 and 100 mm planes above the surface around the tip of the blade.
Air-conditioning in the cabins of passenger cars
(2018) Kumar, S.; Cerny, J.; Kic, P.
The objective of this paper is to analyse the current state of the constructional design and operational conditions of air - conditioning device in passenger cars. The research was focused on the function of air - conditioning equipment of passenger cars Skoda and KIA in various modes of operation during the winter, spring and summer season at different levels of air conditioning (without air - conditioning, minimum, medium and maximum level). Air temperature, air humidity, globe temperature, CO 2 concentration, dust concentration and noise inside the cabin w ere measured. Solar radiation plays a big role to rise up temperature inside the cabin. It resulted in the higher values of globe temperature than temperature of the air. The results of the measurements showed that CO 2 values were significantly lower than 2,500 ppm at minimum air - conditioning, lower than 600 ppm at medium and lower than 500 ppm at maximum level of air - conditioning. For all vehicles, dust concentration was greater when it measured with the air conditioning switched off than with the air con ditioning system turned on. The measurements confirmed that the total dust concentration was not more than 47 μg m - 3 , PM 10 lower than 28 μg m - 3 and PM 1 lower than 27 μg m - 3 . The noise levels ranged from 49.1 to 68.7 dB(A). The air - conditioning had very positive impact on the inside comfort in car cabins from all points of view during all periods of the year.
Alarm guard systems for the prevention of damage produced by ungulates in a chestnut grove of Middle Italy
(2018) Conti, L.; Bartolozzi, S.; Iacobelli, S.; Racanelli, V.; Sorbetti Guerri, F.
Wildlife populations, in particular ungulates and carnivores, have had a significant increase in most Italian regions over the last decades and for this reason ecosystems and agricultural and forest productions are threatened by damage produced by wildlife. In order to evaluate effective met hodologies and technologies to mitigate the impact of this phenomenon, innovative protection systems, such as electronic acoustic alarm guard sensors, were tested. These devices are able to randomly produce a significant number of sounds and light projecti ons. At the same time, camera traps were used, as a support instrument to show the presence or absence of wild fauna. Video analysis has provided information on the effectiveness of security systems, on the most suitable methods of installation and managem ent of devices and their ecological impact. Experimental trials were carried out in a chestnut grove located in an Apennine area of the Middle Italy during the harvesting period (autumn). The results obtained have shown that these technologies seem to be particularly suitable for crops that concentrate production in a short time (e.g. vine and chestnut) and in areas not excessively large. Widespread use of devices could mitigate the conflict between public bodies involved in the management of wildlife and farmers.
Anaerobic co-fermentation of molasses and oil with straw pellets
(2018) Dubrovskis, V.; Plume, I.; Straume, I.
The average grain and straw production in Latvia is increasing in last decade. Straw is not always managed properly and its utilisation in biogas plants can be considered as an alternative. Straw is not the best feedstock for methane production, because it has high C/N ratio. Co - fermentation with other biomass with higher N content can improve the methane production. Purpose of investigation is to evaluate the wheat straw pellets biomass suitability for production of the methane and effect of its co - fermentatio n with molasses, fried sunflower oil and catalyst Metaferm. The anaerobic digestion process for biogas production was investigated in 0.75 L digesters, operated in batch mode at temperature 38 ± 1.0°C. The average biogas yield per unit of dry organic matte r added from digestion of wheat straw pellets was 0.540 L g - 1 DOM and methane yield was 0.285 L g - 1 DOM . Average biogas yield from co - fermentation of wheat straw pellets and molasses was 0.777 L g - 1 DOM and methane yield was 0.408 L g - 1 DOM . Average biogas yie ld from fermentation of wheat straw pellets with 1ml Metaferm was 0.692 L g - 1 DOM and methane yield was 0.349 L g - 1 DOM . Average biogas yield from co - fermentation of wheat straw pellets and sunflowers oil was 1.041 L g - 1 DOM and methane yield was 0.639 L g - 1 DOM . All investigated biomasses can be used for methane production.
Analysis and forecast of performance characteristics of combine harvesters
(2018) Zubko, V.; Roubik, H.; Zamora, O.; Khvorost, T.
This article presents results of an experimental research of qualitative indicators of the modern combine harvesters (Case IH Axil Flow 8230, MasseyFergusonMFT7, JohnDeereS680i, ClaasLexion760, NewHolland CR9.80) used for winter wheat harvesting. Based on the results obtained, determination was made regarding the productivity of combine harvesters on the field, fuel consumption, and field conditions influence the grain loss and grain damage caused by a harvester. When conducting the experimental research of a combine's performance on the field a study of the effectiveness of the combine JohnDeereS680i was made on different modes. A program 'Machine Unit', designed by the authors, was used for the determination of productivity, fuel consumption and quality indicator for harvesting.
Analysis of cost and performances of agricultural machinery: reference model for sprayers
(2018) Yezekyan, T.; Marinello, F.; Armentano, G.; Sartori, L.
Management of agricultural operations is currently rapidly changing caused by increased attention to the concepts of sustainable development and sustainable intensification. Enhancement of productivity and efficiency of agricultural machinery are the leadi ng factors in sustainable agriculture. The complete application and exploitation of engineering advances require the revision of traditional agricultural machinery management process. The definition of the farm fleet (tractors and implements), as well as m achinery planning and management, must consider different parameters, including not only the cost of the machines but also their dimensions, weight, working width, needed power, etc. All of this information related to an agricultural machine is eventually influencing the impact on productivity, on the return on the investmen t, and also on the environment. The present work is aimed at identifying the most relevant parameters which are influencing costs and performances of sprayers, including tank volume, max imum flow, needed power, weight and price. The different parameters are analysed in a correlation matrix, in order to allow identification of dependencies a nd to extract reference models. The study is based on linear and multiple linear regression analysis carried out on technical specifications of about 700 models of sprayers. Relevant correlations were highlighted between price and weight, between weight and tank capacity and in some cases between power and weight . Following such correlations , models have been proposed, which can be implemented in order to support the decision making phases.
Analysis of gamma rays induced variability in lentil (Lens culinaris Medik.)
(2018) Tabti, D.; Laouar, M.; Rajendran, K.; Kumar, S.; Abdelguerfi, A.
In this study, a lentil variety, Idlib-3, was subjected to 100 Gy (LD50) gamma-ray irradiation. At M2, mutant families were characterized for the most beneficial agronomic traits. High genotypic coefficient of variation, broad sense heritability and genetic advance of the traits such as seed yield per plant and hundred-seed weight indicated expression of additive gene action and confirmed the response at early generation selection. Total number of pods per plant had positive correlation and the highest positive direct effect on seed yield per plant and hence the preference should be given for this trait during selection. The novel mutant families identified with early flowering, early maturity (families 5 and 90) in cluster I, and more first pod height (families 10,70 and 82) in cluster II could be utilized to breed short duration lentil varieties suitable for machine harvest.
Analysis of hop drying in chamber dryer
(2018) Rybka, A.; Heřmánek, P.; Honzík, I.
This article is aimed at the analysis of the hop drying process that has been carried out in the chamber dryer of Rakochmel Co. Ltd. in Kolešovice with the Saaz hop variety. The values measured by means of dataloggers as well as fixed sensors show an identical trend. When the hops fall over from one slat box onto another, the drying air temperature declines and the relative humidity rises. A sharp increase in the relative humidity gradually decreases starting with the first slat box and finishing with the emptying conveyor, which points to a gradual levelling of the relative humidity and hop moisture. The hop moisture content, determined from laboratory samples, logically decreases depending on the measurement time. In comparison to belt dryers, chamber dryers clearly ensure continuous and more gentle drying during which the hops are not overdried and a moisture content of 10% is achieved practically only at the outlet of the dryer prior to conditioning.
Analysis of indoor temperature in the workshop building during the summer: a pilot study
(2018) Cao, D.V.; Kic, P.
The aim of this paper is the presentation of measurements' results and the calculation method for analysis and evaluation of climate conditions as well for using of natural illuminance in two large simple buildings during summer which could be used to calc ulate power demand for the air cooling to reduce the indoor temperature caused by solar radiation. In this research, we carried out experiments of measuring the indoor temperature at level of working place which is 1.1 m, in two similar large workshops wit h floor area 260 m 2 and height 6.5 m, during several hot summer days. The indoor conditions were strongly influenced by the solar radiation as the buildings have large wall and roof windows. The indoor air temperatures in the first building achieved 39.5 ° C, which caused the heat stress for workers. The indoor air temperatures in the second building achieved only 29.5 °C. The calculated power demand for the air cooling to reduce the indoor temperature to 25 °C is 25 . 6 kW in the first building, the cooling p ower for second building is 14 . 9 kW. We investigated measured construction of the workshop and we set up the formula in order to calculate thermal balance. The measurement results and calculated results in two buildings are compared and summarized in the t ables and in the graphs for analysis. As a general conclusion, it must be said that solar radiation has a big influence on the air temperature and methods of passive air - conditioning should be more applied also on the production buildings in industry, agri culture and other branches of civil engineering to release heat increasing air temperature inside the building.
Application of conversion model for designing hydrodynamic pumps in turbine mode
(2018) Polák, M.
The use of the smallest water resources has been coming again to the centre of interest in recent years. A water engine – turbine, is the heart of these power plants. This is usually the highest expense for the investor, in terms of cost. The effort is therefore to seek investment less demanding alternatives. One of them is the use of hydrodynamic pumps in reverse turbine operation. This paper provides a methodology for conversion of parameters of the smallest power pumps (micro hydro sites) to turbine operation. The conversion model is based on the results of experimental research at the author's workplace and is suitable for pumps with low specific speeds and outputs. The pump design process for turbine mode is complemented by a practical example for a specific deployment site. This example also serves to verify the accuracy of the conversion model.
The application of micro-wave treatment to reduce barley contamination
(2018) Kretova, Y.; Tsirulnichenko, L.; Naumemko, N.; Popova, N.; Kalinina, I.
The goal of this work is to study the applicability of ultra high frequency electromagnetic field treatment for decontaminating barley grain used in brewing while preserving its technological properties. The germination rates and/or yield of the treated sample seed were compared with those of the untreated seed germinated under normal conditions. To determine optimal treatment conditions, a two-factor analysis was carried out, taking the mycological state of the grain into account. The heating rate and the duration of electromagnetic exposure were chosen as variables; these values varied from 0.4 to 0.8 °C s-1 and from 30 to 90 s, respectively. It was found that germination of the treated barley seed was increased about 10.1–15.7% compared with that of the untreated seed. The microbial load decreased up to 80%. A heating rate of 0.4 °C s-1 and treatment exposure time of 30 s showed the strongest effect of decontamination while preserving the viability of the barley grain.
Assessment of Calotropis natural dye extracts on the efficiency of dye-sensitized solar cells
(2018) Alami, A.H.; Aokal, K.; Zhang, D.; Tawalbeh, M.; Alhammadi, A.; Taieb, A.
This work presents the construction and testing of solar cells sensitized with natural dyes extracted from plants indigenous to the desert. Calotropis plants are self - sufficient as they grow in very harsh environments, and yet are not consumed by humans or livestock due to their irritating agents to the skin and eyes. The energy generators of these plants are the leaves, which are crushed and processed to produce the dye solution. Also, the Calotropis leaves are covered in a white powder that is thought to aid in mitigating the heat by scattering incident radiation. This powder material is examined and added to the dye as it proved advantageous for the o verall cell efficiency, which reached 0.214% compared with 0.108% for cells with no powder. The produced cells are also compared with ones sensitized by spinach, another common natural sensitizer for dye - sensitized solar cells, and the performance proved t o be significantly better. The fact that Calotropis is a non - food plant is an added advantage to utilizing it as a dye source, along with its intrinsic heat resistance that allows it to survive the harsh desert conditions all year round.
Assessment of dairy cow herd indices associated with different milking systems
(2018) Gaworski, M.; Leola, Arvo; Kiiman, Heli; Sada, Oliver; Kic, P.; Priekulis, J.; Estonian University of Life Sciences. Institute of Technology
The objective of the research was to find whether any differences exist between cattle herds operated by certain milking installations. The cattle herds were studied not only by herd size but also by certain data, like annual milk yield, age and number of lactations. Data collected on dairy farms that operate pipeline milking systems, milking parlours and automatic milking systems were analysed. These farms are situated in three Baltic States. The investigated Estonian dairy farms indicated a decreased tendency in the prevalence of disease cases for udder diseases with an increase in cow herd size. An index of cow production potential was proposed to compare different (including number of lactations) group of cows in dairy farms.
Assessment of potato plant development from Minitubers
(2018) Dimante, I.; Gaile, Z.
In production of minitubers, mani pulation of their weight by modifying production method is common. Under field conditions plant development from minitubers can be affected by their weight, as well as cultivar. This objective of this study was to compare plant development from four minitu ber weight classes (MtC) (3 to 4.99 g, 5 to 9.99 g, 10 to 19.99 g, and > 20 g) with broken apical dominance of cultivars ‘Monta’, ‘Prelma’ and ‘Mandaga’. ‘Prelma’ and ‘Mandaga’ had a similar development pattern, and minitubers > 20 g required significantly less growing degree days (GDD) to emerge than minitubers from the lightest classes. The heaviest minitubers needed on average 176 GDD for 50% emergence and 207 GDD were needed for the lightest class. The difference in GDD between the marginal MtC was more pronounced in period between 50 and 80% emergence. MtC did not affect the final rate of emergence. Number of above ground stems (1.4 – 4.0) was significantly affected by MtC. ‘Monta’ had significantly different development – delayed emergence, lower emergen ce rate, less above ground stems, faster canopy closure. Our study showed that plant development was significantly affected by MtC and cultivar. Differences between MtC were more pronounced under adverse meteorological condi tions.
Assessment of soil electrical conductivity using remotely sensed thermal data
(2018) Křížová, K.; Haberle, J.; Kroulík, M.; Kumhálová, J.; Lukáš, J.
Detection of heterogeneity (crop, soil, etc.) gained a lot of importance in the field of site - specific farming in recent years and became possible to be measured by different sensors. The therma l spectrum of electromagnetic radiation has a great potential today and experiments focused on describing a relation between canopy temperature and various vegetation characteristics are conducted. This paper was aimed to examine the relation between canop y temperature and electrical conductivity as one of staple soil characteristics. The related experiment was undertaken in Sojovice, Czech Republic, within an agricultural plot where winter wheat was grown in 2017 growing season. The examined plot was compo sed of three sub plots and 35 control points were selected within this area which the data were related to. A canopy was sensed by UAV (eBee carrying thermoMAP (FLIR TAU2) camera). Soil conductivity data were collected by terrestrial sampling using EM38 - MK 2 Ground Conductivity Meter in 1 m depth and 2 m sampling point distance. This dataset was later interpolated using the kriging method. The correlation analysis results showed a strong negative correlation between conductivity and thermal data ( - 0.82; p < 0.001 ). When comparing conductivity with NDVI representing the aboveground biomass, there was an opposite trend but also strong result (0.86; p < 0.001 ). Correlation coefficient of thermal data and NDVI comparison was - 0.86; ( p < 0.001 ). These preliminary results have a potential for further research in terms of soil characteristics studies.

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