Volume 11 (2013)
  Number I

Supportd by Central Baltic Interreg IV A Programme project ECOHOUSING

Homepage: www.ecohousing-project.eu

Contents


Pages

7-12 L.M. Abenavoli and C. Marcianò
Technical and economic analysis of alternative pruning systems in high dimensions olive trees in Calabria
Abstract |
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Technical and economic analysis of alternative pruning systems in high dimensions olive trees in Calabria

L.M. Abenavoli and C. Marcianò

Agraria Department, Mediterranean University of Reggio Calabria, LocalitàFeo de Vito, 89126 Reggio Calabria, Italy;
*Correspondence: claudio.marciano@unirc.it

Abstract:

Oliviculture in Calabria accounts for 30% of the agricultural gross regionalproduction. On the Gioia Tauro plain, located in the province of Reggio Calabria, theoliviculture area is extended over more than 20,000 hectares. The olive trees in this area arecharacterised by a remarkable growth with trees reaching and often exceeding 25 metres inheight. In these extreme conditions all the cultural operations are technically and economicallycomplex. Particularly complex are the pruning operations, normally done with traditionalmethods, which are dangerous for the operators, who have to climb the trees to make the cutswith chain saws. The objective of this study is to encourage the use of mechanical systems,specifically truck-mounted telescopic platforms, to secure operators and lower the pruningcosts. They were therefore analysed two operating systems, the traditional and the mechanical,comparing the working capacity of different yards. The results have been encouraging althoughthe machines utilised can be rationally introduced only on large farms, while the small farmshave to rely on cooperatives of services or on contractors.

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13-24 A. Bardule,, S. Rancane, I. Gutmane, P. Berzins, V. Stesele, D. Lazdina and A. Bardulis
The effect of fertiliser type on hybrid aspen increment and seed yield of perennial grass cultivated in the agroforestry system
Abstract |
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The effect of fertiliser type on hybrid aspen increment and seed yield of perennial grass cultivated in the agroforestry system

A. Bardule¹,*, S. Rancane², I. Gutmane², P. Berzins², V. Stesele², D. Lazdina¹ and A. Bardulis¹

¹Latvia State Forest Research Institute ‘Silava’, Riga street 111, Salaspils, Latvia;
*Correspondence: arta.bardule@silava.lv
²LLU Research Institute of Agriculture, Zemkopibas instituts 7, Skriveri, Latvia

Abstract:

Agroforestry is a perspective way of biomass production which combines simultaneous growing of woody plants with agricultural crops on the same area for different purposes. The advantage of agroforestry lies in the improved efficiency of resource utilisation and smaller competition of plants for nutrients. In this system the woody plants are less influenced by lasting periods of drought, and a stable annual increase in biomass is ensured. Accordingly, agroforestry is biologically more productive, economically – more favourable, and it is more sustainable than the monocultures of forestry or agriculture separately. The work was done to test the effect of fertiliser type on the increment of two clones of hybrid aspen (Populus tremuloides x Populus tremula) and the seed yield of perennial grasses (Phalaris arundinacea L., x Festulolium pabulare) and legumes (Lupinus polyphyllus L., Galega orientalis Lam.) cultivated in the agroforestry system on loam/sandy soils. Fertilisers used at the planting were wastewater sludge (dose 10 tDM ha-1) and wood ash (dose 6 tDM ha-1). Wastewater sludge fertilisation increased the stem length of hybrid aspen by 20% after the first growing season. The effect of wastewater sludge fertilisation on stem length was still significant after the second growing season. Soil and soil solution analysis indicated that the main Hybrid aspen growth response was due to the P and N supplied by fertiliser. Reed canary grass (RCG), festulolium and fodder galega can be successfully cultivated for seeds in the first year of use, locating the crop fields in the plantations of energy plants interchangeably with trees. The use of wastewater sludge provided an essential increase in seed yields for all species of herbaceous plants. However, the influence of fertilisers on the grass species was different: the greatest increase in seed yields was established by the use of wastewater sludge in RCG, mineral fertiliser in festulolium, and ash in galega, and the fertilisation provided the seed yield increase of 136%, 31% and 163%, respectively.

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25-30 J. Chyba, M. Kroulík, J. Lev and F. Kumhála
Influence of soil cultivation and farm machinery passes on water preferential flow using brilliant blue dye tracer
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Influence of soil cultivation and farm machinery passes on water preferential flow using brilliant blue dye tracer

J. Chyba*, M. Kroulík, J. Lev and F. Kumhála

Czech University of Life Sciences Prague, Faculty of Engineering, Kamýcká129, Prague 6 – Suchdol, 16521, *Correspondence: chyba@tf.czu.cz

Abstract:

Objective of this study was the investigation of water preferential flow into the soilby brilliant blue dye tracer, under different soil tillage treatment and different soil compactioncaused by farm machinery passes. Brilliant blue dye tracer measurement was supported by coneindex measurement. Measurement was carried out on land divided into several options:a) controlled traffic farming (CTF) with loosening, b) CTF with deep loosening before plotestablishment, c) ploughing, d) ploughing with deep loosening before plot establishment. Forthe mentioned measurement options the measurements were performed inside and outside of thetrack lines of agricultural machinery. Representation of the brilliant blue dye tracer inside of thetrack lines significantly decreases at a depth of 5–10 cm for all variants. This trend is stabilisedbetween depths of 0.10 m to 0.4 m with colour coverage ranging between 10 and 20%. Aninteresting fact was that the colour coverage outside of the tracks without deep loosening beforeplot establishment was higher than measurement with deep loosening. The largest statisticallysignificant differences occurred at a depth of 0.3 m, while the most homogeneous groups (froma total of four groups) were found at depths of 0.05 to 0.1 m and 0.25 to 0.3 m. Cone indexmeasurement confirmed almost 100% increase in penetration resistance inside of traffic lines(2. MPa) in comparison with measurements outside of the traffic lines (1. MPa) in the range ofdepth from 0–0.16 m.

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31-38 K. Drastig, S. Kraatz, J. Libra, A. Prochnow and U. Hunstock
Implementation of hydrological processes and agricultural management options into the ATB-Modeling Database to improve the water productivity at farm scale
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Implementation of hydrological processes and agricultural management options into the ATB-Modeling Database to improve the water productivity at farm scale

K. Drastig¹*, S. Kraatz¹, J. Libra¹, A. Prochnow¹⋅² and U. Hunstock³

¹Leibniz-Institute for Agricultural Engineering Potsdam-Bornim, Younginvestigators group ‘AgroHyd’, Department 2 ‘Technology-Assessment andSubstance Cycles’, Max-Eyth-Allee 100, 14469 Potsdam, Germany;
*Correspondence: kdrastig@atb-potsdam.de
²Humboldt-University of Berlin, Faculty of Agriculture and Horticulture, ChairUtilization Strategies for Bioresources, Hinter der Reinhardtstr. 8–18, 10115Berlin, Germany3runlevel3 GmbH, Kastanienallee 94, 10435 Berlin, Germany

Abstract:

To meet the food demands of a growing world population, the productivity ofagricultural water use for food production at farm scale, must be increased. A modelingdatabase has been developed to quantify water use, i.e. the use of precipitation, soil water andirrigation water at the farm scale, and to calculate water-use indicators based on farm operatingdata. These indicators can be used to assess agronomic measures for their merit in improvingthe productive use of water in different agricultural operation systems. The benefit of the ATBModeling Database lies within its speed and inherent flexibility which allows further water-related indicators, management options and water-related processes in different regions andfarm systems to be easily implemented. The description of the ATB Modeling Databasedemonstrates the development of a new solution to handle comprehensive farm and regionaldata, providing a tool to explore possibilities to enhance the productivity of water use indifferent farming systems.Key words: agricultural management options, ATB Modeling Database, data at farm scale,farm-scale, indicators, water productivity.ABBREVIATIONSET0 [mm]: potential evapotranspiration of a grass reference surface;ETc [mm]: potential crop evapotranspiration;ETc,act [mm]: actual crop evapotranspiration;Tc [mm]: potential crop transpiration;Tc,act [mm]: actual crop transpiration.INTRODUCTIONTo meet the future food demands of a growing world population, increases inagricultural productivity over the current level will be necessary. A more productivewater management for securing high water productivity and minimising water losses isone strategy to reduce negative impacts on water quantity in many places (e.g. Gordon31

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39-46 D. Hoffmann, P. Heřmánek, A. Rybka and I. Honzík
Design a drive for interaxle mechanical cutter used in low trellises
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Design a drive for interaxle mechanical cutter used in low trellises

D. Hoffmann*, P. Heřmánek, A. Rybka and I. Honzík

Czech University of Life Sciences Prague, Faculty of Engineering, Departmentof Agricultural Machines; *Correspondence: dhoffmann@tf.czu.cz

Abstract:

A mechanical cutter (similar to a special sprinkler for chemical pruning) serves toprune new hopvine shoots in spring. Depending on the right timing and quality of pruningdepends the later yield, which is why pruning is one of the most important agrotechnicaloperations. Double-disc mechanical cutter used with high trellises cannot be used with thetechnology of low trellises. Due to the effort to minimise the chemical environmental burden,special sprinklers for chemical pruning used abroad are considered inappropriate. This was thereason which led to a design for a mechanical cutter operating in low trellises. The articledescribes a hydraulic circuit design and laboratory measurements of an experimental model ofmechanical cutter.

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47-52 T. Ivanova,, A. Muntean, B. Havrland, and V. Pobedinsky
Theoretical modelling of the briquetting process with different pressing equipment
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Theoretical modelling of the briquetting process with different pressing equipment

T. Ivanova¹,*, A. Muntean², B. Havrland¹, and V. Pobedinsky²

¹Faculty of Tropical AgriSciences, Czech University of Life Sciences Prague,Kamýcká 129, 16500 Prague 6 – Suchdol, Czech Republic;
*Correspondence: ivanova@its.czu.cz
²Faculty of Agricultural Engineering and Auto Transportation, State AgrarianUniversity of Moldova, Mircesti 44, 2049 Chisinau, Republic of Moldova

Abstract:

Recently, a large number of technologies for production of solid biofuels in the formof briquettes has been researched and put into practice. The main advantages and disadvantagesof modern production methods are analysed in this study. The lack of information about theprocess of formation and agglomeration of briquettes of different types of processing equipmentadversely affects the quality of bio-fuel, rapid and intensive wear and tear of the main workingparts and higher energy compaction; this influences the cost of the final product. In order tosolve the above problems, a theoretical modelling of the process of bio-briquettes’ formation onthe piston press is proposed in the present paper. The main task was not only an analysis of theoptimal technologies for briquette production, but also a comparison and elaboration ofmathematical multifactorial linear models of the pressing process. During the theoreticalmodelling the main factors influencing the mechanical quality of briquettes were analysed andcalculated. For a more understandable description of the briquetting process in a piston press,the pressing chamber was divided into three pressing zones. Analysis of forces and pressuredistribution during the passage of material through the pressing chamber was done. The studypretends to improve the design and operational parameters of the pressing equipment.

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53-60 S. Ivanovs,, S. Gach, I. Skonieczny and A. Adamovičs
Impact of the parameters of round and square haylage bales on the consumption of the sealing film for individual and in-line wrapping
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Impact of the parameters of round and square haylage bales on the consumption of the sealing film for individual and in-line wrapping

S. Ivanovs¹,*, S. Gach², I. Skonieczny² and A. Adamovičs¹

¹Latvia University of Agriculture, Research Institute of Agricultural Machinery,
¹ Institute Str., Stopini reg., Ulbroka, Latvia;
*Correspondence: semjons@apollo.lv
²Warsaw Agricultural University, Nowoursynowska 166 St. 02-787 Warsaw,Poland

Abstract:

In the Baltic States and Poland haylage processing in a baled form with subsequentsealing in a flexible film has been intensively applied for about 15 years, and now it occupies animportant place among the forage processing methods. A drawback of this technology is thehigh cost of the film. There are factors investigated having impact on the cost of the film usedfor sealing individual round and square (rectangular) bales separately and in a long line.Comparative estimation has been made of the design values and the experimental data. For bothvariants, the size of the bales being equal, lesser consumption (approximately by 8%) of thefilm will be when the bales are sealed (wrapped). In contrast to individual wrapping of eachbale, in-line wrapping of bales reduces the consumption of the film by two times.

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61-66 A. Kronbergs, E. Kronbergs and E. Repsa
Evaluation of reed canary grass shredding and compacting properties
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Evaluation of reed canary grass shredding and compacting properties

A. Kronbergs*, E. Kronbergs and E. Repsa

Latvia University of Agriculture, Faculty of Engineering, Institute of
Mechanics, J. Cakstes bulv. 5, LV-3001 Jelgava, Latvia;
*Correspondence: andris.kronbergs@llu.lv

Abstract:

Reed canary grass biomass is recommended for solid biofuel production. The main conditioning operation before preparation of herbaceous biomass compositions for solid biofuel production is shredding. Shredding can increase bulk density up to 165 kg m-3. Biomass compacting represents technology for the conversion of biomass into a solid biomass fuel in the shape of briquettes and pellets. Compacting of biomass is one of the important processes for effective handling, transport and storage of this biomass fuel material. The purpose of the work was to investigate reed canary grass (Phalaris arundinacea) comminuting energy, bulk density and briquetting energy dependence on hammer mill screen opening sizes. For comminuting was used a hammer mill, equipped with four different screens with opening sizes 20, 12, 6 and 1.5 mm. Comminuting energy for these opening sizes was stated within 11–236 kJ kg-1 . Bulk density for reed canary grass by comminuting can be increased up to 165 kg m-3 if hammer mill screen with opening size 1.5 mm is used. For briquetting experiments were used a hydraulic laboratory press, where for compacting were used five different pressure levels – 90, 120, 150, 180 and 210 MPa. Maximum density 899–964 kg m-3 had been achieved for compacting pressure 210 MPa. Summary energy consumption for comminuting and briquetting is approximately 50 kJ kg-1 if screen opening sizes are 12 and 20 mm in comminuting. For these sizes briquette density is 899 and 915 kg m-3 .

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67-72 J. Kuht , T. Tõrra, A. Makke, J. Kilgi and E. Nugis
Effect of site-based precision fertilisation on yield and oil content of spring oilseed rape seeds
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Effect of site-based precision fertilisation on yield and oil content of spring oilseed rape seeds

J. Kuht¹ *, T. Tõrra¹, A. Makke¹, J. Kilgi¹ and E. Nugis²

¹Institute of Agricultural and Environmental Sciences, Estonian University of
Life Sciences, Kreutzwaldi 5, EE51014 Tartu, Estonia;
*Correspondence: jaan.kuht@emu.ee
²Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia

Abstract:

The experiments using two fertilisation methods on the spring oilseed rape in 2012 were carried out in two places – on the Eerika experimental field of the Estonian University of Life Sciences and on the Erumäe producing field of the Pilsu farm. The aim of this work was to investigate site-based precision fertilisation on the spring oilseed rape yield and oil content in oilseed rape seeds. The preceding crop was spring wheat in both fields. Five treatments were used: control treatment (without fertilisers, C), common fertilising system (CvS), fertilisation by site-specific information (SI), fertilisation by site-specific information additionally with mineral nitrogen fertiliser (SI+MF), and site-specific fertilisation additionally with foliar nitrogen fertiliser (SI+FF). The highest seed and oil yield was achieved in treatments fertilised by sitespecific information additionally with foliage nitrogen fertiliser. In the production field, the statistically significant seed and oil yield increase was achieved in treatment. Oil content of spring oilseed rape seeds was higher in treatments C and CvS. In both trials, additional fertilising with foliar nitrogen (including microelements, SI+FF) increased the oil content of oilseed rape seeds. There was a negative correlation between the oil content and seed yield of spring oilseed rape.

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73-80 J. Lev,, V. Prošek, M. Wohlmuthová and F. Kumhála
The mathematical model of segmented capacitance sensor with grounded segments for determining of material distribution on the conveyor
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The mathematical model of segmented capacitance sensor with grounded segments for determining of material distribution on the conveyor

J. Lev¹,*, V. Prošek², M. Wohlmuthová³ and F. Kumhála¹

¹Department of Agricultural Machines, Faculty of Engineering, CzechUniversity of Life Sciences Prague, Kamýcká 129, 16521 Prague 6,Czech Republic; *Correspondence: jlev@tf.czu.cz
²Department of Machinery Utilisation, Faculty of Engineering, CzechUniversity of Life Sciences Prague, Kamýcká 129, 16521 Prague 6,Czech Republic
³Department of Mathematics, Faculty of Engineering, Czech University of LifeSciences Prague, Kamýcká 129, 16521 Prague 6, Czech Republic

Abstract:

The need to analyse the material flow on conveyors is an important issue not only inagriculture but also in a number of industries. One of the possibilities is the use of electricalcapacitive sensors. In the past, simple throughput capacitive sensors, but also very sophisticatedelectrical capacitance tomographs were tested. A compromise may be a segmented capacitancesensor. Functional principle is based on the capacitive measurement of the mixture of materialand air several times. From the measured data it is then possible to determinate the parametersof the material distribution. This process is commonly called image reconstruction. Thereconstruction algorithm is very important for development of the mathematical model of thesensor. In this paper the proposed mathematical model for the sensor with grounded SCSsegments was evaluated. This variant of a possible sensor configuration is relatively simple,however, the sensitivity of the sensor in response to changes in the distribution of materialwithin the sensing area is reduced. To verify the mathematical model, a laboratory experimentwas designed. Tested sample was moved inside the sensing area and the response of the sensorwas observed. Proposed mathematical model was confirmed by this measurement. On the baseof measurement results, proposed mathematical model can be used in the development ofreconstruction algorithm.Key words: segmented capacitance sensor, mathematical model, material distribution,throughput.

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81-88 J. Priekulis and K. Vartukapteinis
Rational application of mobile machinery for slurry transportation and distribution
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Rational application of mobile machinery for slurry transportation and distribution

J. Priekulis* and K. Vartukapteinis

Faculty of Engineering, Latvia University of Agriculture, J.Čakstes bulv. 5,LV-3001 Jelgava, Latvia; *Correspondence: juris.priekulis@llu.lv

Abstract:

The article describes the most important versions of slurry transportation and distribution using mobile machinery. Calculation methods of organisation of work, including formulae calculation and description of work planning procedures are given. The principles of mathematical model development that are used for calculation and analysis of slurry transportation and distribution technological parameters are discussed.

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89-96 E. Šarauskis,, K. Romaneckas, A. Sakalauskas, E. Vaiciukevičius,K. Vaitauskiene, D. Karayel and R. Petrauskas
Theoretical analysis of interaction of disc coulters and straw residues under no-tillage conditions
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Theoretical analysis of interaction of disc coulters and straw residues under no-tillage conditions

E. Šarauskis¹,*, K. Romaneckas², A. Sakalauskas¹, E. Vaiciukevičius¹,K. Vaitauskiene¹, D. Karayel³ and R. Petrauskas¹

¹Institute of Agricultural Engineering and Safety, Aleksandras StulginskisUniversity, Studentu 15A, LT-53361 Akademija, Kauno distr., Lithuania;
*Correcpondence: egidijus.sarauskis@asu.lt
²Institute of Agroecosystems and Soil Science, Aleksandras StulginskisUniversity, Studentu 11, LT-53361 Akademija, Kauno distr., Lithuania;
³Department of Agricultural Machinery, Faculty of Agriculture, AkdenizUniversity, TR-07058 Antalya, Turkey

Abstract:

The article presents the theoretical aspects of disc coulters working process under no-tillage conditions. Under no-tillage conditions, effective operation of disc coulters is impededby plant residues. In the interaction of a disc coulter, plant residues and soil surface, the disccoulter may cut the plant residues, roll over them or press them into the furrow being formed inthe soil. The objective of the research is to theoretically study the process of straw cutting bydisc coulters under no-tillage conditions and to substantiate the main parameters acting upon thecutting force. Theoretical studies established the dependency according to each the extent of thestraw cutting force depends on the disc coulter blade sharpening angle, blade thickness and disccoulter blade length, straw normal stresses, friction coefficient, elastic modulus, straw diameter,its compression path, and other parameters. On the basis of calculations, it was found that if thedisc coulter blade sharpening angle is increased by one degree, the cutting force sufficient to cutwheat straw can be reduced by 6.5 N, and reducing the disc coulter blade thickness by onemillimetre would allow reducing the cutting force by 12.5 N.

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97-102 T. Šima,, L. Nozdrovický, K. Krištof, M. Dubeňová and J. Krupička
Effect of the nitrogen fertiliser rate on the nitrous oxide flux from haplic luvisol soil in the laboratory experiment
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Effect of the nitrogen fertiliser rate on the nitrous oxide flux from haplic luvisol soil in the laboratory experiment

T. Šima¹,*, L. Nozdrovický², K. Krištof³, M. Dubeňová⁴ and J. Krupička⁵

1,2,3Slovak University of Agriculture in Nitra, Faculty of Engineering,Department of Machines and Production Systems, Tr. A. Hlinku 2, 94976 Nitra,Slovak Republic;
*Correspondence: tomasko.sima@gmail.com
⁴Slovak University of Agriculture in Nitra, Faculty of Engineering, Departmentof Production Engineering, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic
⁵Czech University of Life Sciences Prague, Faculty of Engineering, Departmentof Agricultural Machines, Kamýcká 129, 16521 Prague, Czech Republic

Abstract:

The aim of the experiment was to study the effect of the variable rate of nitrogenfertiliser on the amount of nitrous oxide (N2O) flux from the soil within a laboratoryexperiment. We have conducted experiments for 30 days under laboratory conditions in order toeliminate the effect of field factors which could affect the results. During the experiment thenitrogen fertiliser DASAMAG® (manufacturer DUSLO, Inc., Slovakia) was used. The haplicluvisol soil properties were determined by pedological analysis. The amount of N2O emissionsemitting from soil was measured by photo-acoustic field gas monitor INNOVA 1412 withmultipoint sampler INNOVA 1309. There were carried out 3 variants of the experiment(application rates 0, 500 and 1,000 kg ha-1) with two replications. The fertiliser wasincorporated into the soil in sampling tubes to a depth of 80 mm after 24-hours measurement.Subsequently, after every 24 hours of measurements, 48 hours rest was carried out, and thismeasuring cycle was repeated 10 times. During the experiment the concentration of emissionsin sampling tubes considerably varied in comparison with the emissions concentration beforefertilising. Maximum values were measured on the 24th day after incorporation of fertiliser forboth application rates. The results of our experiment show that the application rate of fertiliserhas a significant effect on N2O flux and have confirmed the importance of the accurate and evenfertilisers application in order to eliminate the negative environmental effects.

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103-110 T. Šima,, L. Nozdrovický, M. Dubeňová, K. Krištof and J. Krupička
Effect of crop residues on nitrous oxide flux in the controlled traffic farming system during the soil tillage by LEMKEN Rubin 9 disc harrow
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Effect of crop residues on nitrous oxide flux in the controlled traffic farming system during the soil tillage by LEMKEN Rubin 9 disc harrow

T. Šima¹,*, L. Nozdrovický², M. Dubeňová³, K. Krištof⁴ and J. Krupička⁵

¹,²,⁴Slovak University of Agriculture in Nitra, Faculty of Engineering,
Department of Machines and Production Systems, Tr. A. Hlinku 2, 94976 Nitra,
Slovak Republic; *Correspondence: tomasko.sima@gmail.com
³Slovak University of Agriculture in Nitra, Faculty of Engineering, Department
of Production Engineering, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic
⁵Czech University of Life Sciences Prague, Faculty of Engineering, Department
of Agricultural Machines, Kamýcká129, 16521 Prague, Czech Republic

Abstract:

Nitrous oxide (N2O) is one of the most important greenhouse gases. Agriculture, especially soil tillage and the use of fertilisers, significantly contributes to N2O emissions from soil into the atmosphere. The aim of the paper was the comparison of the amount of nitrous oxide emissions released from the soil into the atmosphere depending on crop residues in conditions of a controlled traffic farming (CTF) system. Monitoring points were selected in parts of a field with/ without crop residues and in trafficked and non-trafficked areas. There were realised three variants of the experiment: before soil tillage, right after soil tillage and seven days after soil tillage. Soil tillage was carried out by a LEMKEN Rubin 9 disc harrow with a JOHN DEERE 8230 tractor on the loamy soil after the harvest of winter wheat. The used laboratory method of measuring N2O emissions released from the soil into the atmosphere consists of collecting soil samples from the field and their subsequent analysis in the laboratory. There were used INNOVA devices which consist of a photo-acoustic field gas monitor INNOVA 1412 based on the infrared photo-acoustic detection method, a multipoint sampler INNOVA 1309 used for gas sampling transport to the gas analyser INNOVA 1412, and a notebook with operation software used for the control and setup of the analysis. There was discovered an effect of crop residues and soil compaction on the nitrous oxide flux.

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111-116 T. Šima,, J. Krupička and L. Nozdrovický
Effect of nitrification inhibitors on fertiliser particle size distribution of the DASA® 26/13 and ENSIN® fertilisers
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Effect of nitrification inhibitors on fertiliser particle size distribution of the DASA® 26/13 and ENSIN® fertilisers

T. Šima¹,*, J. Krupička² and L. Nozdrovický³

1,3Slovak University of Agriculture in Nitra, Faculty of Engineering,Department of Machines and Production Systems, Tr. A. Hlinku 2, 94976 Nitra,Slovak Republic; *Correspondence: tomasko.sima@gmail.com
²Czech University of Life Sciences Prague, Faculty of Engineering, Departmentof Agricultural Machines, Kamýcká 129, 16521 Prague, Czech Republic

Abstract:

Effectiveness of the spinning disc fertiliser spreaders is affected by the physicalproperties of the fertiliser. One of the most important factors is the fertiliser particle-sizedistribution which depends upon the size of the fertiliser particles. The aim of the paper wascomparison of two very similar fertilisers from the same manufacturer DUSLO, Inc. usinggranulated nitrogen fertiliser with sulphur content DASA® 26/13 and nitrogen fertiliserENSIN® containing sulphur and nitrification inhibitors dicyandiamide DCD and 1, 2, 4 triazole– TZ. Comparison was done by evaluation of the particle-size distribution of the fertiliserseparated at first in the vertical air flow by K-293 Laboratory screening machine with steeplyincreasing flow speed. The airflow speed was regulated by airflow volume from 60 to 150 m3 h-1. Secondary separation was done by sieve screening of the samples by Haver EML digital plusTest Sieve Shaker. Sieves with square holes with dimensions 1 mm, 2 mm, 3.15 mm, 5 and10 mm were used. Both fertilisers meet the requirements of the manufacturer for grain-sizedistribution. Air flow separation shows higher variability of weight of the ENSIN fertiliserparticles in comparison with DASA fertiliser. Air flow 130 m3 h-1 separated all the particles ofDASA fertiliser. To separate all ENSIN® particles there was used air flow to 150 m3 h-1. Thesedifferences affect the quality of work of the spinning disc fertiliser spreader and cause non-uniformity in the field distribution of fertiliser which has negative environmental andeconomical effects.

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117-124 L. Vent and A. Rybka
Influence of humidity on the quality of baled hops at grower
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Influence of humidity on the quality of baled hops at grower

L. Vent* and A. Rybka

Czech University of Life Sciences Prague, Faculty of Engineering,Kamýcká 129, Praha 6 – Suchdol, Postcode 16521, Czech Republic;
*Correspondence: lvent@tf.czu.cz

Abstract:

Nowadays, in most of cases cured hops are pressed into square bales instead of roundbales. The specific weight of packaged hop is about 22% higher in the square bale and intensityof moistening of packaged hop is very important in this case. There is an increased risk ofdampening of hops in the square bale when the moistening intensity is too high. In the oppositecase is increased risk of destruction of hop cones due to low moistening intensity. The aim ofthis work was find out the influence of the intensity of moistening of hops before pressing intothe square bales on the development of humidity and quality of hops after pressing duringstorage at the grower. There were pressed square bales with humidity of hops from 9.2% to16.2%. The square bales with hop’s humidity 9–10% represented a dry variant, square baleswith hop’s humidity 11–12% represented an normal variant and square bales with hop’shumidity 13% and higher represented a wet variant. The square bales were stored on the firstfloor of the drying machine house at the grower. The range of storage temperature was from 7to 40 °C. All square bales were of the same condition. Humidity of the hops was monitoredduring 10 days. At the end of the measurement, there was carried out a laboratory analysis ofhops of all square bales. Samples were analysed for content of α – bitter acid and destruction ofhop cones. During storage, the humidity of wet variant dropped from 14.2 to 12.7% and thehumidity of dry variant increased from 9.37 to 11.1%. The destruction of hop cones was highestat dry variant (28%). On the contrary the lowest value was at normal variant (12.3%) and it isabout 43% less. However, the dependence of destruction of hop cones by humidity at asignificant level α = 0.05 has not been proven. There was no proven differences of content ofα – bitter acid between all three variants. The highest value 4.9% was at wet variant. We foundout a direct dependence of content of α – bitter acid on the humidity of hops in this case. Theresults of content of α – bitter and destruction of hop cones show that the best one was normalvariant with starting humidity from 11.2 to 11.6%.

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125-130 L. Vent and A. Rybka
Physical characteristics of picked hops during storage
Abstract |
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Physical characteristics of picked hops during storage

L. Vent* and A. Rybka

Czech University of Life Sciences Prague, Faculty of Engineering,Kamýcká 129, Praha 6 – Suchdol, Postcode 16521, Czech Republic;
*Correspondence: lvent@tf.czu.cz

Abstract:

To prevent interrupting the process of drying or picking due to lack or surplus ofhops coming out of the picking line, hops, in most cases are placed in a storage container.. In acontainer, however, hops are layered, thus temperature and humidity increase owing to anincreased intensity of hop cones breathing and an insufficient airing, i.e. they mowburn. In theprocess of breathing a cone loses important substances which results in its deteriorated qualityand correspondingly in the poor quality of the final product. Our task was to observe the courseof hop temperature and humidity in a storage container and to compare it with the checkvariant, which was loosely spread hops outside the container. Data of temperature and humiditywere continually recorded by COMET D 3631 measuring equipment with N1ATG8/Cmeasuring probe by the Comet System company. Other analogue sensors to measure humidityand temperature were independently installed for checking. The monitoring was each timecarried out for 24 hours. During storage both the temperature and humidity of the hops in thecontainer increased substantially, with temperature values reaching up to 49 °C and humidityvalues 100%. The progress of temperatures was almost identical with all the measurements, thatis why we present only the average values. The highest temperature inside the container was inthe range of 39 °C to 49 °C with individual measurements. The temperatures of the checksamples were identical with the air temperature in the daytime with all the repeats. Themaximum temperature of the check samples ranged from 21 °C to 27 °C with eachmeasurement. In the same way as with the temperature, during the individual measurements thehumidity showed similar progress and the measurements did not differ from each other in anysubstantial way. The humidity level in the container rose up to the maximum value of 100%already two hours after the measurement had started and stayed like this until the end. Thehumidity of the hop check samples was 2.24% higher than the air humidity, which might beexplained by water vapour emission due to an increased intensity of hop cones breathing. Theconclusion we may draw here says that with an increasing volume and, probably above all,height of the stored hops layer, the influence of the surroundings on the conditions inside thecontainer will decline.

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133-138 V.V. Мaksarov and A.I. Keksin
Methods of increasing the quality of thread pitches
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Methods of increasing the quality of thread pitches

V.V. Мaksarov* and A.I. Keksin

National Mineral Resources University ‘Mining University’, 21 Line, house 2, Vasilevsky island, 199106 St. Petersburg, Russia; *Correspondent: maks78.54@mail.ru

Abstract:

The article considers the improvement of machining process, namely thread cutting with screw taps, improving quality and stability of roughness of the thread surfaces of high speed cutting steel tools. A scheme of magnetic abrasive polishing and a method of selecting operating conditions of screw taps machining. In the process of elaborating the conditions of the magnetic abrasive polishing process it became clear that one needs different processes for shaping major and minor cutting edges of the taper leads, the sizing parts and the lead-in sections of screw taps. Key words: threaded joints, surface roughness, magnetic abrasive polishing, polishing conditions selection, thread quality.INTRODUCTION

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139-146 V. Mironovs, M. Lisicins, I. Boiko and V. Zemchenkovs
Manufacturing of cellular structures from perforated metallic materials
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Manufacturing of cellular structures from perforated metallic materials

V. Mironovs¹, M. Lisicins¹, I. Boiko²⋅* and V. Zemchenkovs¹

¹Riga Technical University, Laboratory of Powder Materials, Azenes 16/20, LV1048 Riga, Latvia 2Riga Technical University, Institute of Mechanical Engineering, Ezermalas 6k, LV1006 Riga, Latvia; *Correspondence: irina.boiko@rtu.lv Abstract: This research regards the manufacturing of cellular structures with through channels of different form from perforated steel tape. These methods allow recycling of metal wastes (tapes), which are obtained during stamping of fine-sized details. There are given examples of steel wastes with different physical-mechanical properties and geometry. The methods of profiling and welding of thin perforated materials are studied. A method of through channel parameter evaluation is suggested. The estimation of parameters of cellular structures during deformation is suggested. Key words: waste materials, perforated steel tape, cellular structures, deformation.

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INTRODUCTION

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147-154 M. Müller
Research of liquid contaminants influence on adhesive bond strength applied in agricultural machine construction
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Research of liquid contaminants influence on adhesive bond strength applied in agricultural machine construction

M. Müller

Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Science, Kamýcká ¹²⁹, ¹⁶⁵²¹ Prague, Czech Republic; e-mail: muller@tf.czu.cz

Abstract:

An  adhesive  bonding  technology  is  a  prospective  bonding  technology  of  diverse materials.  Namely the research in the  sphere of the degradation aspects affecting the adhesive bond  during  the  technical  life  of  the  adhesive  bonded  complex  is  essential.  Mineral  and industrial fertilisers can be included as significant degradation agents. The aim of the research was to find out the relevant knowledge in the sphere of the degradation of the adhesive bonds placed in the water bath, the oil bath and the solution of the mineral and industrial  fertilisers.  The  experiment’s  results  bring  knowledge  for  producers  of  agricultural machines  introducing  adhesive  bonding  technology  into  their  production  programme.  Two-component constructional epoxy adhesives were tested which were placed into the water bath, the  oil  bath  and  the  solution  of  mineral  and  industrial  fertilisers.  Some  agents  caused  such changes in the adhesive that the adhesive bond strength decreased to zero value already after ⁹0 days.  Significant  changes  of  the  adhesive  bond  strength  occurred  in  the  interval  ¹⁵–⁴⁵  days depending on the adhesive and agents. The strength decrease was connected with the change of a  failure  area  from  cohesive  one  to  combined  and  then  to  adhesive  one.  The  research  showed that it came to diffuse seepage and to a partial corrosion of the adhesive bonded steel samples.

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155-162 M. Müller, and P. Valášek
Assessment of bonding quality for several commercially available adhesives
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Assessment of bonding quality for several commercially available adhesives

M. Müller¹,* and P. Valášek²

¹Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Science, Kamýcká 129, 16521 Prague, Czech Republic;
*Correspondence: muller@tf.czu.cz
²Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Science, Kamýcká 129, 16521 Prague, Czech Republic

Abstract:

An  adhesive  bonding  technology  is  a  prospective  bonding  technology  of  diverse materials.  For  successful  practical  application,  knowledge  gained  by  studying  factors  that significantly influence mechanical properties of the adhesive bonds are essential. The adhesive bond  rise  is  influenced  by  an  increase  of  chemical  –  physical  links.  The  adhesive  bonding strengthens its position in a number of agricultural machines and tools.  The aim of the experiment is to create the adhesive bond which provides the maximum strength and  quality  for  single  combination  of  the  adhesive  and  adherents,  usually  at  minimum  costs. This aim can be reached by describing the process of the hardening and ensuring the optimum adhesive  layer.  Describing  the  adhesive  bonding  process  and  its  factors  is  essential  for companies producing agricultural machinery. From the results of the experiment there is visible a significant fall of the tensile shear strength of  the  adhesive  bond  with  increasing  time  needed  for  the  adhesive  bond  creation.  The experiment  results  also  certified  the  negative  influence  of  the  unequal  adhesive  layer  on  the strength fall but also a huge dispersion variance of results.

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163-170 P. Valášek and M. Brožek Abstract.
Two body abrasion of composites containing filler on the basis of hard cast iron deposits utilisable in agrocomplex
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Two body abrasion of composites containing filler on the basis of hard cast iron deposits utilisable in agrocomplex

P. Valášek* and M. Brožek Abstract.

Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences, Kamýcká ¹²⁹, Praha – ⁶ Suchdol, ¹⁶⁵²¹, Czech Republic; *Correspondence: valasekp@tf.czu.cz

Abstract:

A  row  of  industrial  branches  including  agriculture  requires  materials  resistant  to different  types  of  wear. The  contribution  is  concerned  with  polymeric  particle  composites containing  filler  on  the  basis  of  hard  cast  iron  deposits  chips.  The  interaction  of  polymeric matrix and such  filler creates  wear resistant  material and at the same time  makes possible the low costly recycling of the secondary raw materials. From measured values it is evident that by the addition of hard cast iron deposits chips in the polymeric matrix the sharp increase of wear resistance occurs compared with wear resistance of polymeric material without filler. Such wear resistant composite systems can find utilisation in the agrocomplex field.

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173-182 K. Eisenhuber, A. Jäger, J. Wimberger and H. Kahr
Comparison of different pretreatment methods for straw for lignocellulosic bioethanol production
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Comparison of different pretreatment methods for straw for lignocellulosic bioethanol production

K. Eisenhuber, A. Jäger*, J. Wimberger and H. Kahr

University of Applied Sciences Upper Austria, Stelzhamerstr 23, A 4600 Wels, Austria;
*Correspondence: Alexander.Jaeger@fh-wels.at

Abstract:

In order to reduce carbon dioxide emissions from the combustion of fossil fuels, the production  of  biofuels  from  lignocellulosic  agricultural  residues  is  the  focus  of  industrial  and scientific  interest.  The  feedstocks  of  the  second  generation  used  for  bioethanol  production  are lignocellulose-containing  raw  materials  like  different  types  of  straw,  or  other  plants  like miscanthus x giganteus. In all these plants, the cellulose in the lignocellulose is not accessible to enzymes. Therefore, lignin and/or hemicelluloses have to be removed by a specific pretreatment in order to make enzymatic degradation of cellulose possible. We examined and compared the pretreatment of wheat straw by means of steam treatment and steam explosion treatment. After  hydrolysis,  glucose  concentrations  up  to  ³00 g kg-¹  were  reached  both  for  steam- pretreated straw and steam-exploded straw. After fermentation, ethanol concentrations ranging from  ¹²0–¹⁴0 g kg-¹  were  achieved.  Results  suggest  that  the  explosion  process  slightly  favors the  solubilisation  of  sugars  and,  therefore,  enhances  ethanol  production.  Only  at  higher temperature and longer incubation time does the explosion process not seem to be necessary. In  addition  to  this,  we  examined  most  of  the  lignocellulosic  residuals  in  Austria  available  for bioethanol  production.  As  a  result,  we  can  show  that  even  in  a  country  not  focused  on agricultural production all the bioethanol needed for E¹0 can easily be provided.

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183-188 M. Kaválek,, B. Havrland, J. Pecen, T. Ivanova and P. Hutla
Oil palm shell use as alternative biofuel
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Oil palm shell use as alternative biofuel

M. Kaválek¹,*, B. Havrland¹, J. Pecen¹, T. Ivanova¹ and P. Hutla²

¹Czech University of Life Sciences Prague, Faculty of Tropical AgriSciences, Kamycka 129, 16521 Praha 6, Czech Republic; *Correspondence: kavalek@its.czu.cz 2Research Institute of Agricultural Engineering, Drnovská 507, 16101 Praha 6, Czech Republic Abstract. This study describes analysis of utilisation of shells from the palm oil nuts as a pellet substitute. The analysis of shells from palm nuts processing comprised of the following aspects: analysis of possible utilisation of palm shells as a substitution for standard pellets, assessing physical and chemical properties and emissions released during combustion of palm shells. The performed palm shells´ physical and chemical examination offers opportunity to make conclusion that pellet substitutes based on palm shells are, in comparison to standard woody pellets, of similar or better physical and chemical properties and reach requirements of European standard EN 14961 for solid biofuels. Because it is a waste material from one of the most important oil plants, it is produced in high amounts in tropical zones of many developing countries. It could be successfully used by the commercial companies as a source for small, medium and large scale energy installations. Key words: oil palm, oil palm shell, solid biofuel, waste, pellet, biomass.INTRODUCTION

Abstract:

With increasing consumption of biofuels the demands on researchers to developnew sorts of biofuels are growing in parallel. Utilisation of waste from one of the major oil crops – oil palm is an interesting alternative to existing biofuels.There are two species belonging to the Arecaceae or Palmae (also known asPalmaceae) that are called palm tree. They are used in commercial agriculture for production of palm oil. The African Oil Palm Elaeis guineensis (guineensis refers to its country of origin) is native in West Africa, occurring between Angola and Gambia, while the American Oil Palm Elaeis olifera (from English oliferous, meaning ‘oil-producing’) is native to tropical Central and South America (Lotschert & Beese, 1983). The production of palm oil is directed especially at the food industry and (recently) for production of biodiesel (Mekhilef et al., 2011). The oil contains high amount of beta-carotene. It is used as cooking oil and for production of margarine. Palm oil is also used for biodiesel production, as either a simply processed palm oil mixed with diesel, or processed through transesterification to create a palm oil methyl ester blend which meets the international EN 14214 specification, with glycerin as a by-product (Queiroz et al, 2012).Waste material from palm oil production such as palm shells is produced in hugeamounts with little utilisation. In general, the fresh fruit bunch contains (by weight)183

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189-196 S. Kraatz
Environmental Impact of Corn Grain Ethanol Production focussed on Energy Intensity and Global Warming Potential
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Environmental Impact of Corn Grain Ethanol Production focussed on Energy Intensity and Global Warming Potential

S. Kraatz

Leibniz-Institute for Agricultural Engineering Potsdam-Bornim, Department Technology-Assessment and Substance Cycles, Max-Eyth-Allee 100, 14469 Potsdam, Germany; e-mail: sikraatz@atb-potsdam.de Abstract. The need of fossil fuels and renewable energy is steadily increasing. The evaluation of the sustainability of the bio-fuel production needs to be considered in detail and under a holitistic point of view. The goals of this study are to enumerate the life cycle Energy Intensity (EI) and Global Warming Potential (GWP) of corn grain ethanol production, and to explore ethanol production scenarios which differ at the treatment of the Whole Stillage (WS) co-product, the starch content of the corn kernels and the corn production process at farm scale. A case study of ethanol production in Wisconsin, United States is done. The system boundaries of the investigation are from ‘cradle to plant gate’. In this study statistic data are used for real conditions of corn grain production in Wisconsin. The data for energy use at the biorefinery industrial processes are sourced from an ethanol plant survey. From the comparison of co-product use scenarios, we find that recycling the WS into electricity, heat and fertilizer is the most environmentally beneficial co-product use because it results in a 54% lower EI and a 49% lower GWP than the processing of WS into Distillers Dried Grains with Soluables (DDGS). An increasing starch content of the corn kernels shows a strong decrease of the EI and GWP of the ethanol production up to 20%. Key words ethanol, Life Cycle Assessment, corn, biofuel.

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INTRODUCTION

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197-204 M. Pexa, J. Mařík, K. Kubín and K. Veselá
Impact of biofuels on characteristics of the engine tractor Zetor 8641 Forterra
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Impact of biofuels on characteristics of the engine tractor Zetor 8641 Forterra

M. Pexa¹*, J. Mařík¹, K. Kubín² and K. Veselá¹

¹CULS-Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, 16521, Prague 6, Czech Republic; *Correspondence: pexa@tf.czu.cz
²VUZT-Research institute of Agricultural Engineering p.r.i.; Czech Republic

Abstract:

The European Union currently pays great attention to the possibilities for the use of biofuels  to  power  mobile  machinery.  The  main  reasons  for  the  promotion  of  biofuels  is  the effort of Member States to reduce dependence on oil imports, efforts to reduce emissions from internal  combustion  engines  and  also  efforts  to  support  agriculture.  As  the  best  substitute  for diesel, promoting fatty acid methyl ester, namely in the Czech conditions rapeseed methyl ester (RME). Requirements for diesel fuel are the norm ČSN EN 590 and prescribes requirements for RME standard ČSN EN 14214. At present, based on the requirements of EU directives there is a  mandatory  addition  of  methyl  ester  in  diesel  of  a  maximum  volume  fraction  of  7%.  This blended fuel complies with ČSN EN 590 and can be used without any modification to existing diesel engines. Production of methyl ester of fatty acids is energy intensive and therefore offer, with the allowance made for the structural adjustment of the combustion engine, the possibility to use a mixture of diesel fuel and oil directly. In this paper they are compared on the basis of the  complete  characteristics  of  the  engine  performance  parameters  (torque  and  engine  power) and  minimum  specific  fuel  consumption.  Based  on  standardised  test  NRSC  (non-road  steady cycle)  are  also  compared  smoke  and  fuel  consumption  of  the  internal  combustion  engine  of  a Zetor 8641 Forterra tractor (tractor has worked less than 100 hours). As the fuel is a mixture of different ratios of selected diesel with rapeseed oil, jatropha curcas oil and rapeseed oil methyl ester.

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205-214 V. Pirs and M. Gailis
Research in use of fuel conversion adapters in automobiles running on bioethanol and gasoline mixtures
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Research in use of fuel conversion adapters in automobiles running on bioethanol and gasoline mixtures

V. Pirs* and M. Gailis

Motor Vehicle Institute, Faculty of Engineering, Latvia University of Agriculture,
⁵ Janis Caksteboulevard,LV-3001,Jelgava,Latvia;
*Correspondence: vilnis.pirs@llu

Abstract:

By using fuel conversion adapters, bioethanol and gasoline mixture (E85) can be used in automobiles which are designed to work with fossil fuel. Such adapters increase the amount of the injected fuel, by adjusting the opening time of injectors. Different fuel conversion adapters are available in various automobile markets, for instance, European and North American. The working principles and efficiency of usage of fuel conversion adapters are little researched and there is a lack of scientific studies in this area. The aim of this research is to explore the working properties, efficiency of usage and influence on automobile operational parameters of two different fuel conversion adapters. The authors found a significant difference in the design approach regarding availability of functions, working and regulation principles between different conversion adapters. The increase of the amount of the injected fuel is realised by prolonging of the original injector opening impulse or by generating an additional impulse. Both conversion adapters, subjected to tests, increased the amount of the injected fuel during cold start conditions. During full load conditions, full capacity of fuel injectors was reached and no further enrichment of air/fuel mixture was possible. The findings of the research can be useful for selection of a suitable fuel conversion adapter and providing guidance for designing of better adapters.

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215-220 M. Tutt, T. Kikas and J. Olt
Influence of harvesting time on biochemical composition and glucose yield from hemp
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Influence of harvesting time on biochemical composition and glucose yield from hemp

M. Tutt*, T. Kikas and J. Olt

Institute of Technology, Estonian University of Life Sciences, 56 Kreutzwaldi, EE51014, Tartu, Estonia;
*Correspondence: marti.tutt@emu.ee

Abstract:

Abstract. This article investigates the influence of different harvesting times of hemp samples on their biochemical composition and glucose conversion  yield. Samples  were harvested from experimental fields of the Estonian University of Life Sciences from July to September in 2011. Dilute  sulfuric  acid  solution  was  used  for  pretreatment  in  combination  with  enzymatic hydrolysis.  Results  indicate  that  the  highest  glucose  conversion  rate  of  204.1 g kg-1  of  dry matter of biomass was achieved by samples harvested on the 18th of August. The lowest glucose yield  of  170.3 g kg-1  was  achieved  by  samples  harvested  on  25th  of  August,  which  also  had  a very  low  hydrolysis  efficiency  of  46.9%.  Biochemical  composition  and  glucose  conversion efficiencies of samples vary in time. Samples harvested in September have higher cellulose and lignin  content  than  samples  harvested  in  July.  However,  glucose  conversion  efficiencies decrease significantly in later samples. Average hydrolysis efficiency was 51.4%.  

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223-230 A. Aan and M. Heinloo
Composing and solving differential equations for small oscillations of mathematical spring-coupled pendulums
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Composing and solving differential equations for small oscillations of mathematical spring-coupled pendulums

A. Aan* and M. Heinloo

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56, EE51014 Tartu, Estonia; *Correspondence: aare.aan@emu.ee

Abstract:

This paper shows how to compose differential equations describing the oscillations of mathematical spring-coupled pendulums in a Mathcad worksheet. The composed differential equations are solved using both symbolic calculation features of Mathcad and Laplace transform. On the basis of the obtained solution, a video clip is made to demonstrate the motion of mathematical spring-coupled pendulums. The methods presented in this paper can be used for teaching engineering mathematics and mechanics.

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231-238 M. Gaworski,, A. Leola and J. Priekulis
Comparative analysis on effectiveness of AMS use on an example of three European countries
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Comparative analysis on effectiveness of AMS use on an example of three European countries

M. Gaworski¹,*, A. Leola² and J. Priekulis³

¹Department of Production Management and Engineering, Warsaw University of Life Sciences, Nowoursynowska str. 164, 02-787 Warsaw, Poland; *Correspondence: marek_gaworski@sggw.pl 2Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56, EE51014 Tartu, Estonia 3Institute of Agricultural Engineering, Latvia University of Agriculture, J.Čakstes bulv. 5, LV-3001 Jelgava, Latvia Abstract. Automatic milking system (AMS) belongs to the increasingly significant solutions spread in modern dairy farm production in many countries. But among countries, agriculture and economic conditions can differ widely. As a result there are premises to put the thesis that conditions as well as effectiveness of the AMS use can differ between countries. In order to prove the thesis we have analysed data coming from three European countries. The methodological approach included comparison of data covering technical, biological, economic and technological potential in general and in the selected AMS farms, to propose new indices to express conditions of AMS implementation and their effectiveness in the countries. We would like to conclude that there are considerable differences in effectiveness of AMS use between countries and farms, so it is valuable to exchange experiences resulting from the presented analyses. Key words: AMS, annual milk yield, effectiveness, European countries.INTRODUCTION

Abstract:

Automatic milking system (AMS), named also by the acronyms VMS (voluntarymilking system) and RMS (robotic milking system) constitutes one of the most important solutions demonstrating progress in the modern dairy farm production in the world.The first automatic milking systems (AMS) were installed in the Netherlands in1992. The main reason for investing in an AMS was possible labour savings. Many experiences resulting from AMS management over the last two decades show that there are premises to develop research studies covering technical, technological, health, quality, social, welfare and economic problems. Analyses covering benefits vs. risk as well as some conditions of AMS implementation constitute an important step to recognise additional ways leading to more effective use of automatic milking systems.One of the factors referring to AMS effectiveness is the increased milk yieldresulting from more frequent milking. When milking frequency increased from two times to three times per day an increase from 6 to 25% in complete lactations was231

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239-248 T. Jokiniemi and J. Ahokas
A review of production and use of first generation biodiesel in agriculture
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A review of production and use of first generation biodiesel in agriculture

T. Jokiniemi* and J. Ahokas

University of Helsinki, Department of Agricultural Sciences, Agrotechnology, P.O. Box 28, 00014 University of Helsinki, Finland; *Correspondence: tapani.jokiniemi@helsinki.fi Abstract. Biofuels manufactured by transesterification from organic fats and oils, usually known as first generation biodiesel, have often been rejected in recent energy policy discussions. Major reasons for this have been the low energy return on investment ratio and greenhouse gas emissions emerging from the production of biodiesel raw material. Studies have indicated that total greenhouse gas emissions from the production chain of first generation biofuels can be equal to fossil fuels or even somewhat bigger. However, considering the constantly rising energy prices and decreasing fossil energy resources, and the fact that a true substituent for fossils does not exist at the moment, first generation biodiesel could still offer some new possibilities as an energy source at farm level. Because of the limited production capacity and competition with food production, it would be rational to focus the use of this kind of fuel inside the agriculture system. The object of this review was to examine the use and production of first generation biodiesel at farm level in the present situation. This includes production of biodiesel, suitability for different applications, and economical and environmental evaluation. It was concluded that even though the first generation biodiesel would not reduce emissions, it can assist to save nonrenewable energy. Farm scale biodiesel production is not economically viable at the moment, but the viability is strongly influenced by feedstock price and several other factors. Key words: biodiesel, biofuel, rapeseed, RME, FAME, energy ratio, energy analysis.INTRODUCTION

Abstract:

Biofuels refer to fuels manufactured from different kinds of organic biomass.Since also the fossil fuels are fundamentally organic, another criterion for biofuels is renewability: the raw materials have to renew with the same rate they are used in fuel production. Biofuels can be solid, gaseous or liquid, for example wood in different forms, biogas or carbon monoxide, alcohols and several biodiesel fuels. Absolute advantages of liquid biofuels are the high energy density, homogenous composition and good manageability, which lead to reduced storage space, long operation time without refueling and simple and familiar storage and handling technology. These factors are crucial especially in vehicle and moving machinery applications.Liquid biofuels are usually divided into first and second generation biofuelsaccording to the raw materials and production methods. First generation includes the ‘conventional biofuels, such as alcohols produced by fermentation and fatty acid esters produced from vegetable oils or animal fats. Second generation biofuels can be239

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249-254 H. Lille
Engineering drawing as a visual channel in communication medium
Abstract |
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Engineering drawing as a visual channel in communication medium

H. Lille

Institute of Forestry and Rural Engineering, Estonian University of LifeSciences, Kreutzwaldi ⁵, EE⁵¹0¹⁴ Tartu, Estonia; e-mail: harri.lille@emu.ee

Abstract:

Engineering Graphics is an important technical basic course known as the language of  engineering  and  technology  (design  language)  ‘in  two  dialects’:  the  First-angle  orthogonal projection  (earlier  referred  to  as  method  E)  and  the  Third-angle  orthogonal  projection  (earlier referred  to  as  method  A).  This  course  for  engineering  students  is  essential  for  introducing engineering  to  their  further  studies  and  it  involves  several  disciplines  (e.g.  Machine  Design, Engineering Measurements, Mechanical Engineering Projects). Engineering Graphics serves to create  a  graphic  model  (engineering  drawing)  according  to  which  machine  parts  can  be manufactured  and  machines  and  buildings  can  be  assembled.  Graphic  models  can  also  be considered in the aspect of semiotic principles. The tools of expression of Engineering Graphics are graphic representation, figure (image) and drawing specification, which are perceived by the visual and auditory organs (in the case of verbal contact between the writer of a drawing and the reader of a drawing, i. e. oral form), and represent the means of communication for engineering practice. The requisite elements  for communication are: sender (writer of a drawing), receiver (reader  of  a  drawing),  channel,  medium  and  at  least  a  partially  overlapping  sign  repertoire  of sender and receiver. In order for overlapping to be complete and unambiguous, the Engineering Graphics  course  begins  with  learning  the  design  language  which  is  based  on  graphic conventions.

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255-260 U. Sannik, T. Reede, L. Lepasalu, J. Olt,A. Karus, A. Põldvere, R. Soidla, K. Veri and V. Poikalainen
Utilization of animal by-products and waste generated in Estonia
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Utilization of animal by-products and waste generated in Estonia

U. Sannik¹⋅², T. Reede¹, L. Lepasalu², J. Olt²,A. Karus², A. Põldvere², R. Soidla², K. Veri² and V. Poikalainen²⋅*

¹Competence Center of Food and Fermentation Technologies, Akadeemia tee 15A, EE12618 Tallinn, Estonia 2Estonian University of Life Sciences, Kreutzwaldi 1, EE51014 Tartu, Estonia; *Correspondence: vaino.poikalainen@emu.ee Abstract. Three main directions must be considered in valorisation studies of animal by-products:1. Creation of a monitoring system that reflects the generation of animal by-products andwaste in the food production chain (livestock farming companies – meat industries – marketing and consumer); this includes mapping of by-products and waste, and the creation of a relevant database and models;2. Study of pre-treatment of various types of animal by-products and waste, whichincludes of size-reduction and fractioning as well as a physical and chemical study;3. Studies concerning the use of animal by-products and waste fractions (fat, protein,carbohydrates etc.) for the production of goods and energy. Large amounts of waste and by-products, which are suitable for further use, are generated in the food production chain. Animal by-products and waste consist of organic substances, which contain fat, protein, carbohydrates and often also important bioactive compounds. However, their use in Estonia is still rather modest and there is no complex approach to this. For example, the common technology for processing the by-products generated in meat industry is not designed for optimal use of protein-rich materials suitable for food (connective tissue, tendons, bones, rind and blood) to reduce the deficit of food protein of animal origin, but instead it is used for technical purposes, poured into sewerage or burnt. Many positive examples of the reuse of animal by-products and food waste can be found in European Union Member States (Denmark, Finland, Germany and Austria). This reduces environmental pollution and supplies energy production and industry with additional raw material. In this paper establishing research for a complex approach in the utilisation of animal by-products and waste for food, feed and technical purpose in the production chain is proposed. Keywords: animal by-products, food, feed, energy, biofuels.

Abstract:

INTRODUCTIONFood production volumes generally meet the biological needs of the world’spopulation, but up to a billion people around the world are suffering from hunger due to the uneven availability of food. Deficit for proteins, including protein of animal origin, is high. Proteins of animal origin should comprise approximately half of the255

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