Volume 14 (2016)
  Number 1

Journal Full Text: Vol14No1

Contents


Pages

5-13 A. Aboltins and J. Palabinskis
Fruit Drying Process Investigation in Infrared Film Dryer
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Fruit Drying Process Investigation in Infrared Film Dryer

A. Aboltins* and J. Palabinskis

Latvia University of Agriculture, Institute of Agricultural Machinery, Cakstes blvd. 5, Jelgava, LV – 3001, Latvia:
*Correspondence: aivars.aboltins@inbox.lv

Abstract:

The work analyzes three different product (apple slices, banana slices and grape halves) drying process in the infrared film dryer. Such drying takes place at low temperatures (to 40 °C), allowing to keep the maximum value of fresh products. The drying process is analyzed in detail in the first 8 hours. The quantity of water runoff, drying product temperature changes and flowing air humidity changes during drying were analyzed. It demonstrates the impact of the product placement on the drying progress. Using the experimental data, average diffusion coefficients are obtained for each product group. The results showed that diffusion coefficients were changing during the drying process. Using mathematical modelling and experimental data, the concentration-dependent diffusion coefficient for apple slices was obtained. The study finds that apple and banana drying using the infrared film is comparatively successful, but the drying process of the half of grape berry is slower. This can be explained by the impact of grape peel on the water diffusion.

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14-24 S. Arslan, N. Tursun, F. Kurtulmuş and D. Güleç
Use of thermal images for optimizing burner height, operating pressure, and burner angle of a weed flamer
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Use of thermal images for optimizing burner height, operating pressure, and burner angle of a weed flamer

S. Arslan¹*, N. Tursun², F. Kurtulmuş¹ and D. Güleç³

¹University of Uludag, Faculty of Agriculture, Department of Biosystems Engineering, TR 16059 Bursa, Turkey
²University of Inonu, Faculty of Agriculture, Department of Plant Protection, TR 44100 Malatya, Turkey
³University of Kahramanmaraş Sütçü İmam, Graduate School of Natural and Applied Sciences, Department of Biosystems Engineering, TR 46100 Kahramanmaraş, Turkey
*Correspondence: sarslan@uludag.edu.tr

Abstract:

A two-meter wide prototype weed flamer was developed as a tool for thermal weed control. The weed flamer consists of an LPG tank, pressure regulator, back pressure valve, flow valves, and burners. The burner adjustments are flexible with height setting from 0 to 450 mm and flame angle setting from and 0 to 90°.The thermal camera images were studied at different heights (150, 200, 250, and 300 mm), burner angles (30 and 45°), and pressures (0.1, 0.15, 0.2, 0.25 MPa) to determine the best settings under stationary operating conditions. Based on thermal camera image results, it was found that the burner should be set at 200–250 mm with 0.2–0.25 MPa to obtain the highest temperatures and longest flames. The initial tests of the gas burning system were completed as a broadcast flaming machine and gas doses from 15 to 90 kg ha-1 were applied from 0.25 m above the ground at 30° flaming angle at 0.2 MPa. The dose-response curves of a weed (Convolvulus arvensis L.) were generated to determine the effectiveness of the weed flamer. C. arvensis could be controlled with gas doses from 40 to 82 kg ha-1 depending on the growth stage at 14 day after treatment (DAT). The theoretical field capacity of the 2 m wide flamer varies from 0.32 to 1.62 ha h-1 depending on the gas dose to be applied.

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25-32 V. Dubrovskis and I. Plume
Biogas production from sugar rich waste
Abstract |
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Biogas production from sugar rich waste

V. Dubrovskis* and I. Plume

Latvia University of Agriculture, Faculty of Engineering, Institute of Energetics, Cakstes blvd 5, LV 3001 Jelgava, Latvia;
*Correspondence: vilisd@inbox.lv

Abstract:

56 biogas plants are working today in Latvia. There is need to investigate the suitability of various biomasses for energy production. Sweets production factories by-products are organic waste and wastewater featuring a high sugar content. Wastewater have a high chemical oxygen demand (COD) level and requires special treatment that results in additional input of energy and financial resources. 

This article shows the results of two studies evaluating sugar-containing biomass suitability for the production of biogas.
The anaerobic digestion process of damaged jam and sweets factory wastewater was investigated for biogas production in 0.75 L digesters, operated in batch mode at temperature 38 ± 0.1 °C. The average biogas yield per unit of organic dry matter (ODM) from digestion of damaged jam was 1.114 L g-1ODM and methane yield was 0.716 L g-1ODM. Average biogas yield from digestion of sweets production factory wastewater was 1.058 L g-1ODM and methane yield was 0.663 L g-1ODM. All investigated sugar rich wastes can be utilised for biogas production successfully thus providing an environmental solution for wastewater problem of sweets production factories.

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33-40 M. Gaworski, A. Leola, O. Sada, P. Kic and J. Priekulis
Effect of cow traffic system and herd size on cow performance and automatic milking systems capacity
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Effect of cow traffic system and herd size on cow performance and automatic milking systems capacity

M. Gaworski¹*, A. Leola², O. Sada², P. Kic³ and J. Priekulis⁴

¹Warsaw University of Life Sciences, Department of Production Management and Engineering, Nowoursynowska str. 164, PL02-787 Warsaw, Poland
²2Estonian University of Life Sciences, Institute of Technology, Fr.R. Kreutzwaldi 56, EE51014 Tartu, Estonia
³Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, CZ 16521 Prague 6, Czech Republic
⁴Latvia University of Agriculture, Faculty of Engineering, Cakstes blvd. 5, LV-3001 Jelgava, Latvia
*Correspondence: marek_gaworski@sggw.pl

Abstract:

The objective of the current study was to investigate automatic milking systems (AMS) to find relationships between cow traffic system and efficiency of the AMS use. Milking records of cows from 11 Estonian dairy farms (46 AMS units) as well as data coming from four Latvian (7 AMS units) and two Polish (4 AMS units) dairy farms were analyzed to determine the system capacity. The highest capacity (milk yield per AMS unit per day) for Feed First cow traffic system (mean ± SD) 1,817 ± 276 kg was indicated in Estonian dairy farms. 142 and 255 kg more milk was obtained, respectively, compared with Milk First and Free cow traffic systems. Overall, average milk yield per cow per day was the highest with Milk First cow traffic system – 31.4 kg. It was 3.3 kg higher than with Feed First and 3.5 kg than Free cow traffic systems. The average machine-on time for milking was highest with Feed First traffic system, i.e. 85.3 ± 6.1%. However, the lower percentage of machine-on time for milking was observed for Free and Milk First cow traffic systems (76.4 ± 10.1% and 73.3 ± 7.2%, respectively).

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41-53 J. Kaivosoja and R. Linkolehto
Spatial overlapping in crop farming works
Abstract |
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Spatial overlapping in crop farming works

J. Kaivosoja* and R. Linkolehto

Natural Resources Institute Finland (LUKE), Green Technology, Vakolantie 55, FI 03400 Vihti, Finland
*Correspondence: jere.kaivosoja@luke.fi

Abstract:

A good driving accuracy and a proper machine input control are essential in sustainable farming. The goal is to work on the field exactly according to the plan, for example spraying a certain amount of fungicides evenly to the field. However, without modern assisting systems the farmers tend to overlap their driving lines. So far there have not been quantitative tests to present how mark able this overlapping is in real conditions. To solve this, we collected data from regular farming practices during four years in 17 different fields by recording GNSS (Global navigation satellite system) positions and a relative working status of the implement. We developed data mining methods of finding out the average overwork percentages of regular crop farming practices within different complete field plots. Based on the cumulative work distance, we measured the minimum overlapping percentage of different field works. The average minimum overlapping percentages for different machinery were: sprayer 15.7%, combine driller 7.7%, combine harvester 1.7%, spin disk fertilizer 9.5%, cultivator 19% and roller 59%. To understand reasons for great deviation between similar works, we determined different overlapping components for the spraying work: 2/3 of the spraying overlap was because of the driving line inaccuracies while the remaining 1/3 happens in the headland turns. This detected overlapping leads to the over consumption of pesticides, seeds, fertilizers, fuel and time but it can be minimized by applying accurate steering assistance and by adapting automatic section controls.

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54-66 K. Kall, Ü. Roosmaa and R. Viiralt
Assessment of the economic value of cattle slurry and biogas digestate used on grassland
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Assessment of the economic value of cattle slurry and biogas digestate used on grassland

K. Kall¹*, Ü. Roosmaa¹ and R. Viiralt²

¹Institute of Economics and Social Sciences, Estonian University of Life Sciences,
Kreutzwaldi 1, EE51014 Tartu, Estonia
²Institute of Agricultural and Environmental Sciences, Estonian University of Life
Sciences, Kreutzwaldi 64, EE51014 Tartu, Estonia
*Correspondence: katri.kall@emu.ee

Abstract:

 Concentration of dairy production and development of manure handling technologies has led to large amounts of cattle slurry produced as a by-product. Slurry can be used directly for fertilisation or input for biogas production. As a result of added organic materials, the nutrient content of the by-product of anaerobic digestion (biogas digestate) differs from nutrient content of slurry. The data from the 2012 to 2014 field experiment designed to evaluate the use of local organic fertilisers on grassland were used for the current study. The objective of this research is to present an approach for the fair reflection of the economic value of organic fertilisers. The approach is based on substitution relationships between mineral and organic fertilisation on a certain yield level of grass dry matter production. The economic value was assessed based on the nutrient content of cattle slurry and biogas digestate, application costs, and the cost of mineral fertilisation. Two categories of economic value were calculated: the total and the actually realised value. The total economic value shows the potential value of nutrients available for plant production. The actual realised value is formed through the nutrient usage by plants. The economic value of the biogas digestate used in the experiments appeared to be higher than the value of slurry, due to the equal application of ammonium nitrogen (NH4-N), the higher content of potassium and lower application rates.

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67–74 N. Kamińska, M. Gaworski, P. Kaźmierska and A.M. Klepacka
Pilot study of variability on demand and knowledge concerning organic food on an example of two Polish regions
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Pilot study of variability on demand and knowledge concerning organic food on an example of two Polish regions

N. Kamińska*, M. Gaworski, P. Kaźmierska and A.M. Klepacka

Department of Production Management and Engineering, Warsaw University of Life
Sciences, Nowoursynowska str. 164, PL 02-878 Warsaw, Poland
*Correspondence: natalia.kaminska@poczta.onet.pl

Abstract:

The paper focuses on showing variability of knowledge and demand for organic food in two regions of Poland, i.e. Świętokrzyskie and Mazovian provinces. The selected for detailed investigations Polish regions differed in society wealth. Mazovia province with capitol (Warsaw) is reach as opposed to Świętokrzyskie – mountain province with dominance of more difficult conditions for comfort and affluent life. Basing on questionnaire the group of respondents’ attitude towards organic food was recognized and compared. The problems included in the questionnaire there were factors influencing the organic food buying, factors which influence about the resignation of organic food buying, the availability of information about organic food, availability of organic food in selected regions, requirements for organic food, most frequently purchased organic products, place where consumers buy organic food, consumption frequency of organic food, factors influencing the choice of organic food. The comparison of two provinces indicated differences within the meaning of organic food as well as autonomy in consumer behaviour. Polish society is characterized by a growing interest in organic food. The production industrialization and mass food processing causes people to look for some alternatives. Organic farming gives people that chance. In the conclusions, we have formulated a term mean that due to the consumption of organic products – ‘we are what we eat’.

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75–81 P. Kic
Dust pollution in the sport facilities
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Dust pollution in the sport facilities

P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Technological Equipment of Buildings, Kamycka 129, CZ 16521 Prague,
CzechRepublic; e–mail: kic@tf.czu.cz

Abstract:

The aim of this paper is to present the results of microclimatic research focused on the dust pollution in several buildings and different rooms used for sport activities at the University. The attention is paid mainly to the problems of dimensions of space, capacity and activity of sportsmen, and influence of space ventilation. In the frame of this research the concentration of air dust was measured by the exact instrument DustTRAK II Model 8530 aerosol monitor. Using the special impactors the PM1, PM2.5, PM4, PM10 size fractions were also measured. Obtained results of measurements were evaluated and concentrations of different size of dust particles were analysed. Results of different indoor conditions were generalized. Based on the results of measurements practical recommendations for the design, use and ventilation of these types of buildings were summarised in the conclusions.

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82–90 P. Kic
Microclimatic conditions in the poultry houses
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Microclimatic conditions in the poultry houses

P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Technological Equipment of Buildings, Kamýcká 129, CZ 165CZ 21 Prague,
Czech Republic; Correspondence: kic@tf.czu.cz

Abstract:

The aim of this paper is to present the results of microclimatic research focused on the indoor conditions in several agricultural buildings used for fattening of chicken broilers. The attention is paid mainly to the construction of the building and its position in the farm area, which together with technological equipment of the building, floor covering, and system of ventilation, can influence the microclimatic conditions inside the halls. In the frame of this research main parameters of internal and external properties of climate were measured and evaluated. Themeasurement results of the air temperature, humidity, globe temperature, concentration of CO2, dust pollution and surface temperatures show rather important role of the overall layout of buildings, influence of the wind and solar radiation together with surroundings. The research results show that to the improvement of internal microclimate can contribute significantly the use of principles of passive air conditioning. The acquired new knowledge can be useful not only to improve the current situation on the farm, but mainly for the improvement of the building
constructions in similar new farms.

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91–108 J. Kukk and A. Leppiman
The construct of value in knowledge-intensive business service from customer’s perspective. An example of a long-term training activity
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The construct of value in knowledge-intensive business service from customer’s perspective. An example of a long-term training activity

J. Kukk* and A. Leppiman

Tallinn University of Technology, School of Economics and Business Administration,
Department of Business Administration, Chair of Marketing, Akadeemia tee 3,
EE 12618 Tallinn, Estonia
*Correspondence: janakukk@gmail.com

Abstract:

Value is considered to be the driver, as well as the main purpose, of relationships between customers and service providers. Despite the topicality of the subject, service marketing literature provides little information about the process of value creation. The question of how is value formed is topical for a broad scope of services, from healthcare to beauty services, but it is especially relevant for knowledge-intensive business services (KIBS). KIBS are complex offerings that aim to solve customer’s problem by applying competence of service provider (for example consultancies and training services). It happens quite often that those types of services fail to meet the expectations of the customer regarding service value. This mismatch between service value and price charged might come from a broad variety of reasons. This ambiguity of value creation process leads to the research question of the current article: how do clients identify, what the service is actually worth? The current article presents the results of longitudinal qualitative research on service value formation from the customer’s perspective. It aims to provide insights both for researchers as well as practitioners on elements of service, based on which client forms the perception of the value of KIBS and also illustrated the dynamics.

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109–122 D. Lazdiņa, S. Šēnhofa, M. Zeps, K. Makovskis, I. Bebre and Ā. Jansons
The early growth and fall frost damage of poplar clones in Latvia
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The early growth and fall frost damage of poplar clones in Latvia

D. Lazdiņa*, S. Šēnhofa, M. Zeps, K. Makovskis, I. Bebre and Ā. Jansons

Latvian State Forest Research Institute ʻSilava’, Rigas 111, LV 2169 Salaspils, Latvia
*Correspondence: dagnija.lazdina@silava.lv

Abstract:

The early growth and frost damage of Populus spp. was studied in two sites. The height of 23 five-year-old poplar clones was measured in the central part of Latvia; and the early-fall frost damage of 19 one-year-old and two-year-old poplar clones were assessed in the eastern part of Latvia. The relation between the height growth and frost damage of 16 clones, which were common for both sites, was assessed. The phenologically dormant stage was denoted for three clones, among which two are collected across Latvia (the origin un-known; introduced in 1960s). All the other clones had trees with damaged leaves and two clones had stem damage. The height of the clones ranged from 273.3 ± 60.2 to 711.0 ± 32.0 cm. The 3 most productive clones (LV3, LV1 and LV4) significantly (P < 0.01) exceeded others, by 34 and 65% for height and biomass, respectively. The mean height of these clones was 649.0 ± 21.5 cm and stem biomass varied from 33.7 ± 4.2 to 55.0 ± 6.4 tfresh=ha-1 (planting density 6,500 trees=ha-1). The clone had significant (P < 0.01) effect on the phenological stage, leaf and stem frost damage, as well as on the height and stem biomass. No relation (P > 0.05) between the frost damage of leaves and both tree height and stem biomass was found. The results suggest that fast-growing frost-tolerant clones might be selected.

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123–133 A. Lēnerts, D. Popluga, K. Naglis-Liepa and P. Rivža
Fertilizer use efficiency impact on GHG emissions in the Latvian crop sector
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Fertilizer use efficiency impact on GHG emissions in the Latvian crop sector

A. Lēnerts¹, D. Popluga¹*, K. Naglis-Liepa¹ and P. Rivža²

¹Latvia University of Agriculture, Faculty of Economics and Social Development,
Institute of Economics and Regional Development, Svetes street 18, LV-3001, Jelgava,
Latvia
²Latvia University of Agriculture, Faculty of Information technologies, Liela street 2,
LV-3001, Jelgava, Latvia
*Correspondence: dina.popluga@llu.lv

Abstract:

Within increasing production activity Latvian agricultural sector has become one of the main sources of greenhouse gas emissions (GHG) in Latvia. In 2013, agricultural sector contributed 21.0% of the total GHG emissions originated in Latvia (2310.1 Gg CO2eq). Analysis of agricultural GHG emissions by sources shows that direct N2O emissions from agricultural soils through the usage of synthetic fertilizers are one of the most significant GHG source in Latvia. The usage of synthetic fertilizers is one of the most common widespread agricultural practices in Latvian cropping systems and according to statistical data usage of synthetic fertilizers is constantly increasing, for example, in 2013 it increased by 6.9% if compared with 2012. Taking into account that over-fertilization can lead to negative economic and environmental consequences, such as high production costs, depletion of energy resources, and increased GHG emissions, this research aims to estimate how effective usage of synthetic fertilizers are in Latvian crop farms. In order to achieve the set aim an N fertilizer usage were estimated in four crop farms by giving insight into N balance and N use efficiency (NUE) rate in these farms. Research results suggest that improved N efficiency can be selected as GHG mitigation measure as it reduces N surpluses and the use and production of mineral fertiliser while maintaining yield levels. It was also concluded that improved N efficiency reduces direct N2O emissions from fertilized soils and indirect N2O emissions that occur by the release of NH3.

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134–142 K. Makovskis,, D. Lazdina, A. Arsanica and V. Solodovniks
Mechanical durability and water absorption of pellets made from different tree species – a case study
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Mechanical durability and water absorption of pellets made from different tree species – a case study

K. Makovskis¹,*, D. Lazdina¹, A. Arsanica² and V. Solodovniks²

¹Latvian State Forest Research Institute ‘Silava’, 111 Riga street, LV–2169 Salaspils,
Latvia
²LTD NewFuels, 169a Atbrivosanas aleja, LV – 4604 Rezekne, Latvia
*Correspondence: kristaps.makovskis@silava.lv

Abstract:

Seven different tree species (coniferous and broad leaved) were selected for small scale pelletizing tests: birch (Betula sp.), aspen (Populus tremula L.), grey alder (Alnus incana L.), poplar (Populus sp.), European larch (Larix decidua Miil.), pine (Pinus sylvestris) and lodgepole pine (Pinus contorta). Tree species were mixed in different combinations and proportions. Wood mixture from one tree specie (several tree species were tested as base material during study) was used as base material with volume share in the mix at least 70% and mixtures from other tree species were used as additives. In total 49 different tree mixes were tested in pellet production where mechanical durability and water absorption was later measured for each sample. Mechanical durability where grey alder was mixed with pine was 98.8% (fulfils ENplus quality class). Poplar also showed high results and in some mixes meet the criteria for mechanical durability with best result 99% in mixes with European larch and lodgepole pine (proportions 80:10:10). From 9 different poplar mixes 7 of them showed mechanical durability higher than 97.5%. In tests where no additives was added (100% poplar), poplar pellets mechanical durability was 98.8%. Other mixes with birch, aspen and grey alder when they were taken as base material for pellet production (base material wood volume share in the mixture at least 70%, where remaining 30% consists of other tree specie mixtures) didn’t meet the mechanical durability limit for ENplus quality classes and it was lower than 97.5%. Also in samples where birch and grey alder were used without adding other tree species durability was under 97.5%. European larch was the only one from coniferous trees was tested as base material and the best results in mechanical durability showed in mixes with lodgepole pine (proportion 70:30). From 9 different European larch mixes 7 of them showed mechanical durability higher than 97.5%, which is suitable for ENplus certification. Water absorption in pellets with different tree species  composition does not change significantly and ranges from 0.70 to 0.73 ml g-1 when in commercially available litter material it is 0.75–0.8 ml g-1. Water absorption tests leads to a conclusion that if pellets mechanical durability is not sufficient to sell it as combustion material in could be sold as litter material for animals.

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143–149 R. Mieldažys, E. Jotautienė, A. Pocius and A. Jasinskas
Analysis of organic agricultural waste usage for fertilizer production
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Analysis of organic agricultural waste usage for fertilizer production

R. Mieldažys*, E. Jotautienė, A. Pocius and A. Jasinskas

Aleksandras Stulginskis University, Faculty of Agricultural Engineering, Institute of
Agricultural Engineering and Safety, Studentu g. 15b, LT-53361, Akademija, Lithuania
*Correspondence: ramunas.mieldazys@asu.lt

Abstract:

Waste management, especially biodegradable (organic) waste, is highly relevant in agriculture. Increasing the intensity of agricultural production inevitably increases pollution of soil, water and air due to chemical, biological and other effects because of untidy agricultural waste. Currently there is a search for new and more rational ways to use waste for new forms of energy, making fertilizer, building materials and other products. One of the processes of biodegradable waste management is pelleting; i.e., the processing of recyclable materials into organic ecological products.
The SWOT analysis-expert, literature survey methods were used for the analysis of animal and plant origin organic agricultural waste’s suitability for production of fertilizer. The analysis has shown that the granulation of animal waste allows making better use of nutrients, significantly reduces the amount of fertilizer needed to be deposited into the soil and reduces the cost of storing, transportation and spreading into the soil. SWOT analysis motivated the need for further research of manure waste and its pelletizing.

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150–159, M. Ojasoo and A. Leppiman
Ethics audit as a marketing instrument and its potential for organic farming
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Ethics audit as a marketing instrument and its potential for organic farming

M. Ojasoo* and A. Leppiman

Tallinn University of Technology, Faculty of Economics, Institute of Business
Administration, Ehitajate tee 5, EE19086 Tallinn, Estonia
*Correspondence: merle.ojasoo@ttu.ee

Abstract:

Demand for organic foods is growing quickly but remains to be a relatively small segment of the food market. In order to increase the market share there is important role in an effective and smart marketing communication. According to many researches consumers are mostly interested in additional ethical attributes in organic food producing. Organic food farmers’ ability to earn profit from experience marketing according ethical values in organic food production is rather weak. At the same time organic farming faces many significant ethical risks from unregulated area of organic food-production. Consumer trust in environmentally friendly or organic products is often being undermined by business scandals, unsubstantiated ‘organic’ claims and assessment practices. The current paper aims to improve ethics audit framework as a marketing instrument for organic farming companies in order to increase the trust between producers and consumers. This paper draws upon previous researches and adds new approach based on the needs of organic farming.

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160–166 L. Paura and D. Jonkus
Use of automatic system for pig feed consumption control
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Use of automatic system for pig feed consumption control

L. Paura* and D. Jonkus

Latvia University of Agriculture, Faculty of Agriculture, Institute of Agrobiotechnology,
Liela str. 2, LV-3001, Jelgava, Latvia
*Correspondence: liga.paura@llu.lv

Abstract:

The aim of this study was to analyse average daily gain and feed conversion ratio, and to estimate daily gain and feed conversion ratio during the pig fattening period. 100 pigs from the same herd were housed in pens of around 10–15 animals and fed ad libitum with one single-place electronic feeder. Average on-test weight and off-test weight were 34.8 kg and 119 kg, respectively. Average daily gain, average daily feed intake and feed conversion ratio were computed. During investigation the average daily gain was 0.788 kg, the daily feed intake was 2.25 kg and feed conversion ratio was 2.86 kg. The differences in investigated traits between male and female pigs were significant. Generally, male pigs had greater off-test weight (+7.3 kg, p < 0.05), average daily gain (+0.037 kg, p < 0.1) and feed conversion ratio (+0.13 kg) in the fattening period. Average daily gain and feed conversion ratio were also calculated based on 100 kg off-test weight. If pigs will be fattening till 100 kg, than daily feed conversion ratio decreased and is 2.25 kg, but average daily gain increased and is 0.840 kg. The average fattening duration when pig has 100 kg off-test weight was 154.8 days. Phenotypic correlations between production and feeding traits were calculated. Correlation between average daily gain and feed conversion ratio was moderate negative (r = -0.542), pigs with higher average daily gain had better feed conversion ratio.

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167–173 B. Peterka, M. Pexa, J. Čedík and Z. Aleš
The influence of biobutanol on performance parameters of mobile generator
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The influence of biobutanol on performance parameters of mobile generator

B. Peterka, M. Pexa, J. Čedík* and Z. Aleš

Czech University of Life Sciences Prague, Faculty of Engineering, Department for
Quality and Dependability of Machines, Kamycka 129, CZ 165 21 Prague 6,
Czech Republic; *Correspondence: cedikj@tf.czu.cz

Abstract:

The expansion of biofuel also affects the area of using small internal combustion engines, which are widely used in municipal equipment such as minitractors,  chainsaws, mowers and brush cutters. These small engines have their specific  operation conditions, especially given by high operating speeds and high loads. Current legislation for fuel BA 95 prescribes the addition of ethanol. The percentage is however very small nearly not affecting the operation of combustion engines. The paper is focused on biobutanol since it is considered as more advanced type of alcohol based fuel than bioethanol. The measurement is focused on a small combustion engine of portable generator with maximum power of 2.5 kW. There is monitored influence of biobutanol on their performance parameters. As the mixing ratios are in the range of 100% fuel BA 95 (without ethanol) to 100% biobutanol.

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174–180 F. Pfannerer, K. Krennhuber, A. Jäger and H. Kahr
New constructs for ethanol production via cyanobacteria
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New constructs for ethanol production via cyanobacteria

F. Pfannerer¹, K. Krennhuber¹, A. Jäger¹ and H. Kahr¹*

¹University of Applied Sciences Upper Austria, R&D, Franz-Fritsch-Straße 11,
AT 4600 Wels, Austria
*Correspondence: Heike.Kahr@fh-wels.at

Abstract:

Alternatives to fossil fuels must be developed due to several already known reasons. Bioethanol can be an attractive energy concept. Bioethanol gasoline hybrid fuel can be used by most internal combustion engines. First and second generation bioethanol production is already available – here agricultural crops or residues are utilised. There are controversial discussions about these bioethanol production methods – the food versus fuel debate, cost and energy efficiency. Alternative advanced bioethanol production must be established with competitive production costs. Photosynthetic prokaryotes like cyanobacteria are attractive organisms for this purpose – these prokaryotes are fast growing organisms and utilize solar energy and CO2. But these prokaryotes must be genetically manipulated for ethanol production. In this study transformation was performed using homologous recombination to introduce the pyruvate decarboxylase (pdc) and alcohol dehydrogenase B (adhB) genes  of Zymomonas mobilis into the photosynthetic prokaryote Synechococcus elongatus PCC 7942 genome. These cyanobacteria grow in fresh water and seawater or even in wastewater. Both genes were expressed under the control of the strong constitutive promoter of psbA1 gene (encoding photosystem II protein D1). Various cloning strategies were done. Each construct was transformed successful in Synechococcus elongatus PCC 7942 and the potential bioethanol production was determined with HPLC. Only one construct produces bioethanol at detectable level. Diverse reactors and scale up steps were done to increase the bioethanol production. Anyhow further cloning strategies must be implemented to improve the production rate to achieve an effective bioethanol production from Synechococcus elongatus PCC 7942.

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181–197 M.R. Picornell-Buendía,, A. Pardo-Giménez and J.A. de Juan-Valero
Reuse of spent mushroom substrate by modification and its qualitative parameters
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Reuse of spent mushroom substrate by modification and its qualitative parameters

M.R. Picornell-Buendía¹,*, A. Pardo-Giménez² and J.A. de Juan-Valero¹†

¹Escuela Técnica Superior de Ingenieros Agrónomos de Albacete, Castilla – La Mancha
University, Campus Universitario s/n, E02071, Albacete – Spain
²Centro de Investigación, Experimentación y Servicios del Champiñón (CIES),
C/Peñicas, s/n. Apartado 63, 16220 Quintanar del Rey – Cuenca, Spain
*Correspondence: MRaquel.Picornell@hotmail.com

Abstract:

In this study the agronomic viability of Pleurotus ostreatus (Jacq.) P. Kumm. is studied by reusing the spent substrates previously used in crops of the same mushrooms. After the physical and chemical characterization of the substrates, we have evaluated qualitative production parameters in one growing season. As base material, the experiment was arranged with wheat straw (WS) and spent Pleurotus substrate (SPS) to generate prepared substrates with the participation of the same, alone and mixed in different proportions with wheat bran (WB). Unsupplemented SPS, supplemented SPS with 600 g of WB, mixture of WS + unsupplemented SPS, and mixture of WS + supplemented SPS with 600 g of WB, are prepared substrates that have achieved acceptable crude protein content in fruit bodies at the expense losing texture, but not firmness. Also these substrates promote brightness, and yellow-blue (b*) and red-green (a*) chromaticity of the harvested mushrooms.

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198–210 S. Rancane, A. Karklins, D. Lazdina, P. Berzins, A. Bardule, A. Butlers and A. Lazdins
The evaluation of biomass yield and quality of Phalaris arundinacea and Festulolium fertilised with bio-energy waste products
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The evaluation of biomass yield and quality of Phalaris arundinacea and Festulolium fertilised with bio-energy waste products

S. Rancane¹*, A. Karklins², D. Lazdina³, P. Berzins¹, A. Bardule³, A. Butlers³ and A. Lazdins³

¹Latvia University of Agriculture, Institute of Agriculture, Lielā iela 2, LV-3001,
Jelgava, Latvia
²Latvia University of Agriculture, Faculty of Agriculture, Institute of Soil and Plant
Sciences, Lielā iela 2, LV-3001 Jelgava, Latvia
³Latvia State Forest Research Institute ‘Silava’, Rīgas iela 111, LV-2169 Salaspils,
Latvia
*Correspondence: sarmite.rancane@inbox.lv

Abstract:

 Tall growing perennial grasses such as Phalaris arundinacea and Festulolium can be used as an alternative source for bioenergy production in northern latitudes as they can be grown in less cultivated areas and can be potentially used as a dual purpose crop (bioenergy and forage). The aim of studies was to investigate the effectiveness of using bioenergy waste products – fermentation residues (digestate) and wood ash as fertilisers for perennial grasses. The field experiment was conducted in the central part of Latvia (56°42′ N and 25°08′ E) from 2013 to 2015. For all fertiliser treatments (wood ash, digestate once per season; digestate twice per season and mineral fertilisers) the same amount of plant nutrients (N, P, K) was applied annually: N (100), P2O5 (80), K2O (160); and the missing quantities of elements in ash and digestate were compensated by mineral fertilisers. Dry matter yield (DMY) in two harvest regimes (single cut and two cut) and chemical composition (ash content; total C and N) of grass biomass partitioning among tillers, leaves and panicles were estimated.
Biomass yield in the three years of use varied considerably depending on the fertiliser, harvest regime and species, ranging up to 10.0 Mg ha-1 for RCG and 7.73 Mg ha-1 for festulolium. All fertilisers provided a significant increase of DMY, however, better results for both species were obtained using wood ash and mineral fertilisers. The harvest regime and species affected directly the quality of biomass, single cut of RCG contained significantly less ash and more carbon. There were significant differences between sward fractions – culms in comparison with leaves contained less ash and nitrogen, and more carbon, what are desirable features for solid fuel.

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211–219 Z. Roja, H. Kalkis, I. Reinholds and A. Cekuls
Ergonomics risk analysis in construction operations
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Ergonomics risk analysis in construction operations

Z. Roja¹, H. Kalkis²*, I. Reinholds¹ and A. Cekuls³

¹University of Latvia, Faculty of Chemistry, Ergonomic Research centre, Jelgavas street
1, LV-1004 Riga, Latvia
²Riga Stradins University, Faculty of European Studies, Dzirciema street 16, LV-1007
Riga, Latvia
³University of Latvia, Faculty of Economics and Management, Department of
Management, Aspazijas blvd. 5, LV-1050 Riga, Latvia
*Correspondence: henrijs.kalkis@gmail.com

Abstract:

The research focuses on analysis of ergonomics risks among construction workers in different operations at work. The aim of the research is to carry out ergonomics risk analysis in various construction operations and to prove that physically hard manual work and application of force in manual work operations affect muscular fatigue, using objective and subjective risk assessment methods, including extended version of Nordic musculoskeletal questionnaire, myotonometric measurements, muscle’s force determination with dynamometer. During the research it was proved that the combination of objective and subjective ergonomics risk analysis methods provides holistic approach and reliable ergonomics risk analysis results.

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220–227 E. Runno-Paurson, R. Kiiker, A. Aav, M. Hansen and I.H. Williams
Distribution of mating types, metalaxyl sensitivity and virulence races of Phytophthora infestans in Estonia
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Distribution of mating types, metalaxyl sensitivity and virulence races of Phytophthora infestans in Estonia

E. Runno-Paurson*, R. Kiiker, A. Aav, M. Hansen and I.H. Williams

Estonian University of Life Sciences, Institute of Agricultural and Environmental
Sciences, Department of Plant Protection, Kreutzwaldi 1, EE51014 Tartu, Estonia
*Correspondence: eve.runno-paurson@emu.ee

Abstract:

 Potato late blight, caused by the oomycete Phytophthora infestans, is a destructive potato disease, causing considerable crop loss worldwide. As the late blight pathogen population is diverse and variable in Estonia, changes in the population should be monitored regularly. In this study, the Estonian population of P. infestans was characterised with mating type, sensitivity to metalaxyl and virulence on potato R-gene differentials. During the growing season 2013, 110 isolates were collected from nine potato fields. The frequency of A2 mating type was on average 29%, and varied significantly between different fields from 7% to 78% (p = 0.001). On all studied potato fields, both mating types were recorded, suggesting continuous sexual  reproduction of P. infestans and possible risk of oospore production and early attacks of late blight in Estonian potato fields. The prevalence of metalaxyl sensitive isolates in the population (64%) differed from results from previous research. Thus changes have occurred in the P. infestans Estonian population. There were no significant differences in metalaxyl sensitivity between studied fields (p = 0.073). The Estonian race structure was highly diverse and complex, on average 7.2 virulence factors per isolate, but varied between fields from 5.6 to 9.0. 42 virulence races were found; the four most common were 1.2.3.4.5.6.7.8.10.11, 1.2.3.4.6.7.8.10.11, 1.2.3.4.7.10.11 and 1.2.3.4.7.8.10.11, which comprised 46% of the population. The overall normalized Shannon’s diversity index was 0.69, confirming the high diversity of the population. Continuous pathogen population studies describing the contemporary P. infestans population are essential in order to advise potato breeders and growers accordingly.

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228–235 J. Said, Š. Boďo, T. Saady, R. Gálik, S. Sardary and K. Abbas
Effect of broiler chickens living conditions on results of fattening
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Effect of broiler chickens living conditions on results of fattening

J. Said², Š. Boďo¹*, T. Saady², R. Gálik¹, S. Sardary² and K. Abbas²

¹Department of Production Engineering, Faculty of Engineering, Slovak University of
Agriculture in Nitra, Tr. A. Hlinku 2, SK 949SK 76 Nitra, Slovak Republic
²Agricultural College, Salahaddin University-Erbil, Karkuk St. Erbil, Kurdistan region,
Republic of Iraq
*Correspondence: stefan.bodo@uniag.sk

Abstract:

This work was aimed to monitor outdoor temperature, air humidity and internal microclimate conditions in broilers house during summer days, the temperature and the quality of bedding material as well as bird density. To evaluate the quality of litter we set three-tier system. If the litter dry and hard – value was ‘1’ if it was moist and supple – value was ‘2’, and if it was wet – value was ‘3’. The measurements were carried out on the 10th and 20th days of chickens age. Air temperature was monitored by (logger Comet R 3120) thermometer and for the measurement of the litter temperature used a non-contact thermometer (Raytek Raynger ST). To find out the birds density a thermocamera (Guide TP8S) for thermal imaging was used and subsequent shots are evaluated the birds stocking density. If the bird density high, value was ‘1’, if the bird density median, value was ‘2’ and if the density low, value was ‘3’. The hall was divided into 33 rectangular shapes. Results showed that the bedding quality averageed 1.2 on day 10 and 1.3 on day 20 of fattening (dry and hard). By comparing the P values and the significance level α (0.05), the value of 0.651 and 0.820 was found respectively for both age. No significance was detected between the litter temperature and the litter quality, also between bedding temperature and birds density. Intercomparison for bedding temperature and quality on days 10 and 20 a significant difference (0.000 < 0.05) was observed.

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236–243 N. Siņicina and A. Martinovs
Changes in air ions concentration depending on indoor plants activity
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Changes in air ions concentration depending on indoor plants activity

N. Siņicina* and A. Martinovs

Rezekne Academy of Technologies, Faculty of Engineering, Atbrīvošanas aleja 115,
Rēzekne, LV-4601, Latvia
*Correspondence: natalija.sinicina@rezekne.lv
Abstract. Lack of negative ions in the air can cause deterioration

Abstract:

 Lack of negative ions in the air can cause deterioration of the health which is described in many scientific articles. At the same time, an air saturated with negative ions can improve the state of health and provide a comfortable indoor environment. In addition, there are considerable evidences that drowsiness, apathy, headache etc. get even worse indoors, and these health problems may be effectively eliminated with a help of moderate concentrations of negative ions. Literature sources and earlier researches state that plants may be able to produce a variety of air ions, including negative light ions. The most plants emit different types of volatile organic compounds, and the indoor plants can improve the air quality: they effectively remove organic pollution and reduce the number of microorganisms in the air by releasing phytoncides. In this article, the regularity of influence of plants on the number of ions in the room is being proved, basing on a series of experiments performed with the following plants: Spathiphyllum, Pinus mugo, Aloe arborescens, Chlorophytum comosum, Cactaceae opuntia.

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244–250 K. Sirviö, S. Niemi, S. Heikkilä and E. Hiltunen
The effect of sulphur content on B20 fuel stabil
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The effect of sulphur content on B20 fuel stabil

K. Sirviö*, S. Niemi, S. Heikkilä and E. Hiltunen

University of Vaasa, Faculty of Technology, PL 700, FIN-65101 Vaasa, Finland
*Correspondence: katriina.sirvio@uva.fi

Abstract:

The aim of this study was to investigate if a high amount of sulphur is favourable for the fuel blends’ storage stability. The parameters that correlate with the storage stability of the fuel blends were compared with two B20 fuel samples consisting of 20 vol% biodiesel and 80 vol% fossil diesel. The studied parameters were the oxidation stability (OSI), acid number and kinematic viscosity. The measurements were carried out straight after mixing the blends, and again after 4 and 9 weeks. One of the B20 samples was prepared from rapeseed methyl ester (RME) and fossil diesel fuel containing 6.6 mg kg-1 sulphur and the other from the same RME but the fossil diesel fuel contained 186 mg kg-1 of sulphur. According to the results of this study, the fuel containing less sulphur had slightly better quality during the entire study. Though, the OSI of the fuel containing more sulphur decreased less in percentages than it did for the fuel containing less sulphur. As a conclusion, the study gives a reason to assume that the sulphur may be favourable to fuel blends’ storage stability but it should be studied for a longer time to confirm this statement. 

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251–258 L. Sisenis, B. Dzerina,, K. Udris, L. Purina, S. Luguza and J. Katrevics
Impact of browsing damages on growth and quality of silver birch plantations in Latvia
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Impact of browsing damages on growth and quality of silver birch plantations in Latvia

L. Sisenis¹, B. Dzerina²,*, K. Udris¹, L. Purina², S. Luguza¹ and J. Katrevics²

¹Latvia University of Agriculture, Forest Faculty, Akademijas 11, LV 3001 Jelgava,
Latvia
²Latvian State Forest Research Institute ʻSilava’, Rigas 111, LV 2169 Salaspils, Latvia
*Correspondence: baibadzerina@inbox.lv

Abstract:

 Silver birch is widely used both in forest regeneration and afforestation of abandoned agricultural lands, since it has high productivity and phenotypic plasticity and is relatively seldom damaged by biotic or abiotic factors. In Baltic States significant browsing damage of this tree species had not been noted in contrast to other countries with notably higher ungulate population densities. Therefore the aim of our study was to evaluate the impact of browsing damages on tree and stand parameters as a basis for further recommendations for stand protection. Data for the analysis were collected in central Latvia (56°22´N, 23°7´E) in a large plantation with areas of different browsing intensity. At the age of 16 years, tree height and diameter was measured and traits characterising damages were assessed. Browsing had caused a significant decrease in survival: from 87% survival in areas with light browsing to 56% survival in areas with heavy browsing. Browsing had caused a reduction of tree growth: mean tree height in areas with slight browsing was 13 ± 0.4 m, but only 2 ± 0.3 m (i.e. reaching height of red deer and moose) in areas with heavy browsing. Heavy browsing had created irreversible loss of productivity: even if browsing would not continue, it would take double as much time for the birches in these areas to reach target diameter for cutting (27 cm) than in slightly browsed areas. Frequency of spike knots and crooked stems was statistically significantly higher for trees with browsing damage.

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259–268 D. Streikus, A. Jasinskas, M. Arak, E. Jotautienė1, R. Mieldažys, S. Čekanauskas and Z. Jankauskienė
Investigations of fibre plants preparation and utilization of solid biofuels
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Investigations of fibre plants preparation and utilization of solid biofuels

D. Streikus¹, A. Jasinskas¹*, M. Arak², E. Jotautienė1, R. Mieldažys¹, S. Čekanauskas³ and Z. Jankauskienė⁴

¹Aleksandras Stulginskis University, Faculty of Agricultural Engineering, Institute of
Agricultural Engineering and Safety, Kaunas-Akademija, Studentu str. 15A, LT-53361
Kaunas r., Lithuania
²Estonian University of Life Sciences, Institute of Technology, Fr.R. Kreutzwaldi 56,
EE51014 Tartu, Estonia
³Aleksandras Stulginskis University, Experimental Station, Kaunas-Akademija,
LT-53361 Kaunas r., Lithuania
⁴Lithuanian Research Centre for Agriculture and Forestry, Upyte Experimental Station,
Linininku str. 3, Upyte, LT-38294 Panevezys r., Lithuania
*Correspondence: algirdas.jasinskas@asu.lt

Abstract:

Presented research results of technological-technical means and operations for solid biofuel preparation: chopping, milling, pelleting and burning of fibre plants – 3 sorts of fibre hemp (Beniko, Bialobrzeskie and Epsilon 68) and fibre nettle (sown in 60 x 60 cm). These fibre plants were grown in the experimental fields of Lithuanian Research Centre for Agriculture and Forestry, Upytė Experimental Station, and in Aleksandras Stulginskis University were investigated the technical means of these plants preparation and usage for energy purposes. It was used the standard methodology for solid biofuel preparation of fibre plants, and was investigated the technique for plant chopping, milling and pelleting. There were determined fibre plant mill fractional composition while usage the hummer miller prepared mill. There were determined the fibre plant pellet quality indicators – moisture content and bulk density. The fibre plant pellet moisture content ranged from 6.4% to 8.8%, and pellet density reached 1,082.7–1,186.2 kg m-3 DM (dry matter). Pellet elemental composition, ash content and calorific value were determined at the Lithuanian Energy Institute. The ash content after the burning of fibre plant pellet was not high and varied from 3.6 to 5.9%. Determined net calorific value of fibre hemp and fibre nettle dry mass was relatively high 17.2–17.5 MJ kg-1, it was close to calorific value of some wood species.

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269–279 R. Zewdie, and P. Kic
Transport route segments and stress effect on drivers
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Transport route segments and stress effect on drivers

R. Zewdie¹,* and P. Kic²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Vehicles and Ground Transport, Kamýcká 129, CZ-165 21, Prague 6, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ-165 21, Prague 6, Czech Republic
*Correspondence: Zewdie@tf.czu.cz

Abstract:

Drivers are expected to drive safely whilst carrying out a variety of complex tasks using physical, sensor, cognitive and psychomotor skills. In this paper, the authors examine the influence of road characteristics and microclimate influence in driver’s cabin, on different drivers’ performance while accomplishing their daily duties. The authors gave prior emphasis on transport route profiles like pedestrian crossing, road junctions, round about; pulling in and out of each bus stop and other unexpected incidences on driver’s attention. The research was held on different drivers on the same transport route and segment of articulation. Work experiences, unfamiliarity of the routes were among the key factors for increasing stress and decreasing drivers’ attention. This paper analyse stress factors on drivers during the summer period of driving performance. The core data on microclimate situation in the driver’s cabin and the heart rate are preserved through careful measurements on all route segments. The drivers’ heart rates are carefully recorded at specific parts in the road to examine how the road characteristics affect driver’s behaviour. The influence of route characteristics, the microclimate influence in the drivers cabin, and other complications in transport route on heart rate variations of different drivers is the output of the research findings.

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280–289 K. Tamm, E. Nugis, L. Edesi, E. Lauringson, L. Talgre, P. Viil, T. Plakk, T. Võsav, R. Vettik and P. Penu
Impact of cultivation method on the soil properties in cereal production
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Impact of cultivation method on the soil properties in cereal production

K. Tamm¹*, E. Nugis¹, L. Edesi¹, E. Lauringson³, L. Talgre³, P. Viil¹, T. Plakk¹, T. Võsav, R. Vettik¹ and P. Penu²

¹Estonian Crop Research Institute, J.Aamisepa 1, EE48309 Jõgeva, Jõgeva Vald, Estonia
²Agricultural Research Centre, Teaduse 4/6, EE75501 Saku, Estonia
³Estonian University of Life Sciences, Kreutzwaldi 1, EE51014 Tartu 4, Estonia
*Correspondence: kalvi.tamm@etki.ee

Abstract:

The aim of present paper is to give an overview about results collected in 2012–2014 related to impact of cultivation method on the cereal field soil properties. Experiments were conducted on Estonian farmers’ production fields to compare no-till and plough-based tillage practices. Studied properties were among others soil bulk density, structure, water content, microbial activity and weeds seeds content.
The bulk density, gravimetric moisture content and structure of soil from 0–10, 10–20 and 20–30 cm layers were evaluated. For microbial activity an enzyme  dehydrogenase, which occurs in all viable microbial cells, was determined in soil layers 0–10 and 10–20 cm. Soil samples were taken from 0–25 cm layer to determine weed seeds content. Seeds were extracted from the soil using a flotation-method. The seeds were counted and species identified under the microscope.
The cultivation method has significant impact on some soil properties and insignificant to other. Cultivation method had no significant impact on ratio of agronomically preferred soil particles (2–4.75 mm). No-tilled fields soil bulk density had no differences between layers except 0–10 layer in Pärnumaa (p < 0.05). Soil bulk density differences (p < 0.05) between layers occurred in Soth-Viljandimaa and Pärnumaa tilled soils, in which plough pan in layer 20–30 cm was noticeable.
In average the abundance of weeds seeds was higher on no-tilled fields, compared to tillage accordingly 60,975 and 29,250 weed seeds m-2 (p < 0.003). Results showed higher soil dehydrogenase activity in the no-tilled soils layer 0–10 cm than in 10–20 cm layer (p < 0.05). In the tillage the dehydrogenase activity had no significant difference between soil layers.

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290–296 J. Tuure, A. Rammo and J. Ahokas
Realtime soil moisture measurement during field work
Abstract |
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Realtime soil moisture measurement during field work

J. Tuure¹, A. Rammo² and J. Ahokas¹*

¹University of Helsinki, Department of Agricultural Sciences Agrotechnology,
Koetilantie 5, FI 00014 Helsinki, Finland
²University of Mosul, College of Agriculture, Mosul Iraq
*Correspondence: jukka.ahokas@outlook.com

Abstract:

Soil moisture affects grain germination. If the seeds are sown in dry soil the germination is poor and the emergence is uneven. In Finland, the fieldwork during the spring sowing season takes a couple of weeks and during this period the soil is drying or it is wetting if there are rains. If the seeds can be sown to optimal soil moisture content this enhances germination and increases the yield.
Soil moisture content and temperature was measured before spring tillage. By utilizing these results a prototype of soil moisture measurement system was built utilizing commercial NIRtechnology moisture sensor. This system could be used in harrows and drills so that the work is done to proper soil moisture content. The principle functioned reliably when properly calibrated and mounted. The measuring system could be further improved with narrower light beam so that the falling soil aggregates would not have interference to the results. This kind of instrumentation could be used in implements.
Harrowing and sowing season could be prolonged with a small impact on yield if the seeds could be sown to advantageous moisture content. This would be also economical because the work capacity and machine sizes could be reduced. Also risk of soil compaction would be less.

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297–302 K. Veselá, M. Pexa and J. Pavlů
The water content in the engine oil by using E85
Abstract |
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The water content in the engine oil by using E85

K. Veselá*, M. Pexa and J. Pavlů

Czech University of Life Sciences Prague, Faculty of Engineering, Department for
Quality and Dependability of Machines, Kamycka 129, CZ 16521, Prague 6,
Czech Republic
*Correspondence: katerina86@email.cz

Abstract:

The European Union adopted a decision to achieve by 2020 at least 20% reduction in greenhouse gas emissions. To fulfill this task, the EU proposed in 2020 binding targets – further improve energy efficiency by 20%, achieving a 20% share of renewable energy and a 10% share of biofuels in the fuel market. One of the most widely used biofuel in the automotive industry is bioethanol. Bioethanol can be used on low-percentage blending into petrol, which is governed by European Directive 2003/30/EC, and on high-blend bioethanol mixture, particularly E85 consists of 85% bioethanol and 15% petrol BA95. But in recent years, increasingly demonstrating opinions, that biofuels do not produce nearly as much effect as was propagated. This paper deals with the concentration of water in the engine oil with using biofuel E85. The water in the engineoil significantly affects its parameters (especially viscosity). How measurement results demonstrated the use of bioethanol in the fuel increases the concentration of water in the engine oil.

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