Volume 18 (2020)
  Special Issue I

Full text of the journal: Volume 18 Special issue I

Contents


Pages

679–688 P. Alao, M. Tobias, H. Kallakas, T. Poltimäe, J. Kers and D. Goljandin
Development of hemp hurd particleboards from formaldehyde-free resins
Abstract |
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Development of hemp hurd particleboards from formaldehyde-free resins

P. Alao¹, M. Tobias¹, H. Kallakas¹, T. Poltimäe¹, J. Kers¹ and D. Goljandin²

¹Laboratory of Wood Technology, Department of Material and Environmental Technology, Ehitajate tee 5, EE19086 Tallinn, Estonia
²Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate tee 5, EE19086 Tallinn, Estonia
*Correspondence: percy.alao@taltech.ee

Abstract:

Low density of hemp hurd (Cannabis Sativa L), better end of life impact, performance comparable to wood chips and low energy requirement for cultivation make it a suitable alternative raw material for particleboards (Pb). However, due to concerns about sustainability and formaldehyde emissions, it is essential to develop the new bio-based resins from renewable resources. In this research, the mechanical and physical properties of Pb produced from hemp hurds (HH) and a variety of resins: Urea-formaldehyde (UF), formaldehyde-free acrylic resin (Acrodur®) and bio-based soy resin (Soyad™) were compared to those of wood particles (WP) bonded with UF. The results indicate that boards from HH are generally lighter than WP with a 5.6% variation between HH+UF and WP+UF. Hemp boards based on soy-resin showed higher tensile performance, with an average of 0.43 MPa compared to the 0.28 MPa and 0.24 MPa of (HH+UF) and (WP+UF) respectively. Nevertheless, thickness swelling (TS) of HH+UF (27%) was the least, while there was no significant difference in the water absorption (WA) compared to HH+Soyad4740, both were still lower than that of WP+UF. The overall outcome shows that bio-based soy resin can be a suitable alternative to UF as a binder in Pb production.

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689–698 R.R. Andrade, I.F.F. Tinôco, F.A. Damasceno, M. Barbari, D.A. Valente, M.O. Vilela, C.F. Souza, L. Conti and G. Rossi
Lighting and noise levels in compost dairy barns with natural and forced ventilation
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Lighting and noise levels in compost dairy barns with natural and forced ventilation

R.R. Andrade¹*, I.F.F. Tinôco¹, F.A. Damasceno², M. Barbari³*, D.A. Valente¹, M.O. Vilela¹, C.F. Souza¹, L. Conti³ and G. Rossi³

¹Federal University of Viçosa, Department of Agricultural Engineering, Av. Peter Henry Rolfs, s/n Campus University of Viçosa, BR 36570-900, Viçosa, Minas Gerais, Brazil
²Federal University of Lavras, Department of Engineering, BR37200-000 Lavras, Minas Gerais, Brazil
³University of Florence, Department of Agriculture, Food, Environment and Forestry, Via San Bonaventura, 13, 50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it, rafaella.andrade@ufv.br

Abstract:

The housing system, called compost barn, is attracting the interest of several farmers. It allows dairy cows to remain in free movement inside a shed without any containment partitions like those used in freestall barns. In Brazil the compost barns with open sides are very common, but recently some closed barns with climatic control systems have been implemented. The objective of this work was to evaluate and compare lighting and noise levels in an open compost barn with natural ventilation and in a closed compost barn with a climate control system. The latter one is based on tunnel ventilation: inlet of air trough evaporative cellulose panels and exit through fans placed on the opposite wall. Through analysis of the collected data it was observed that the sound pressure recorded inside both analysed buildings did not exceed the ranges of noise discomfort recommended for the rearing of animals. However, the sound pressure amplitude inside the barn with climate control system was greater than in the open barn. The light intensity was significantly lower in the closed barn when compared to the open barn (84.96 and 1,413.58 lx, respectively). The artificial lighting system distributed throughout the closed barn was not sufficient to maintain brightness within the recommended range for lactating cows. In addition, it was found that in the closed building with forced ventilation, the highest brightness values are located near the exhaust fans.

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699–719 C.B. Aramian, F. Barcelos, F.C. Silva, D. Cecchin, A.R.G. Azevedo and D.F. Carmo
Sustainability indicators in cooperative management of recyclable materials
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Sustainability indicators in cooperative management of recyclable materials

C.B. Aramian, F. Barcelos, F.C. Silva, D. Cecchin, A.R.G. Azevedo and D.F. Carmo

Federal Fluminense University (UFF), Engineering school, Department of Agricultural
Engineering and Environment, Street Passo da Pátria, n.156, postal code: BR24210-240,
Niterói, Rio de Janeiro, Brazil

Abstract:

Following the promulgation of the National Solid Waste Policy in 2010, legal provisions, government programs and sectoral agreements have been implemented, but without the expected efficiency in relation to recycling. It should be noted that Cooperatives of Recyclable Material Pickers (CRMP) should play a leading role in this regard, but they do not have adequate management to be economically, socially and environmentally sustainable, depending on assistance to maintain the activity. Aiming to elucidate this issue, in this paper was made an institutional diagnosis of the category of waste pickers using the Gramacho region in the city of Duque de Caxias (Rio de Janeiro) as a case study. It was carried out an evaluation of the historical context of the neighbourhood, and it was drawn up a semi-structured questionnaire in 12 of the 18 cooperatives in the region. The data were interpreted through a SWOT matrix and the Venn diagram. A matrix was proposed and elaborated with 15 sustainability indicators specific to the CRMC reality in order to evaluate and monitor the management of cooperatives. After collecting the primary data, it was possible to validate the matrix of indicators with indexes of cultural, economic, political and ecological sustainability of the cooperatives. It was found that the matrix of indicators facilitated the understanding of the data and the comparison between the indicators. This tool can help decision-making, creation of action plans and identification of demands by the cooperative waste pickers themselves, without the presence of an analyst or technician.

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720–728 O. Bolotnikova,, J. Bazarnova, E. Aronova and T. Bolotnikova
Study of transhydrogenase systems features in the mutants of the yeast pachysolen tannophilus for the production of ethanol and xylitol from agricultural wastes
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Study of transhydrogenase systems features in the mutants of the yeast pachysolen tannophilus for the production of ethanol and xylitol from agricultural wastes

O. Bolotnikova¹,², J. Bazarnova², E. Aronova² and T. Bolotnikova²

¹Petrozavodsk State University, Institute of Medicine, Department of
biomedical chemistry, immunology and laboratory diagnostics, Lenina Str., 33,
RU 185910 Petrozavodsk, Republic of Karelia, Russia
²Peter the Great St. Petersburg Polytechnic University, Graduate school of biotechnology and food science, Polytechnicheskaya Srt., 29, RU 195251 Saint Petersburg, Russia

Abstract:

The key catabolic enzymes of D-xylose, an important structural component of different agricultural wastes, were studied in cells of mutant strains of the xylose-assimilating yeast Pachysolen tannophilus. The evaluation of catalytic activity and cofactor specificity of xylose reductase (ЕС 1.1.1.307) and xylitol dehydrogenase (ЕС 1.1.1.9) confirmed the dependence of intracellular catabolic pathway for D-xy lose on the NAD×H/NADP×H ratio, formed under microaerobic conditions. The study of total activity of some NAD+/NAP×H-dependent dehydrogenases revealed the metabolic characteristics of the yeast cells, which could ensure selective ethanol or xylitol production. Thus, the efficient involvement of D-xylose into the Embden–Meyerhof–Parnas pathway provided not only the high activities of xylose reductase and xylitol dehydrogenase, but also of 1-glycerophosphate dehydrogenase (EC 1.1.1.8) and lactate dehydrogenase (ЕС 1.1.1.27), respectively. The inhibition of activity of these enzymes led to selective production of xylitol from D-xylose. On the base of the experimental results, the principles of metabolic engineering of xylose-assimilating yeasts were formulated. The possibility of bioethanol and xylitol production from different agricultural wastes using xyloseassimilating
yeasts are discussed.

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729–741 J. Brovkina, G. Shulga, J. Ozolins, B. Neiberte, A. Verovkins and V. Lakevics
The advanced application of the wood-originated wastewater sludge
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The advanced application of the wood-originated wastewater sludge

J. Brovkina¹*, G. Shulga¹, J. Ozolins², B. Neiberte¹, A. Verovkins¹ and V. Lakevics²

¹State Institute of Wood Chemistry, Dzerbenes street 27, LV–1006 Riga, Latvia
²Riga Technical University, Faculty of Material Science and Applied Chemistry, Paula Valdena street 3/7, LV–1048 Riga, Latvia
*Correspondence: yuli@inbox.lv

Abstract:

The wood hydrothermal treatment is one of the plywood production’s stages, which resulting in the production of wastewater containing such components as hemicelluloses, lignin and wood extractive substances (HLES). It is necessary to improve the wastewater treatment technology with the aim to enhance the yield of sludge from plywood wastewater for its effective and rational recycling. In the present study, the optimal coagulation conditions for the HLES removal have been found using the developed aluminium salt-based coagulant. The developed composite coagulant is characterized by lower doses, a wide range of the work pH values, the insensitivity against temperature changes and a higher coagulation efficacy compared with traditional aluminium salts. The proposed treatment technology generates many tons of wood-originated sludge – a biomass coagulate. It was found that the formed coagulate produced in the process of wastewater treatment can increase the sorption ability of clay. The optimal content of the dry coagulate in a clay sorbent does not exceed 0.11%. The sorption capacity of the developed sorbent for water, rapeseed and silicone oil increases by 35%, 31% and 21%, respectively, relative to the unmodified clay sorbent. The sorption efficiency of heavy metals from water solutions is also increased by 10–12%. The thermal treatment of the modified clay sorbent at the high temperature leads to an increase in its sorption capacity for oil products.

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742-754 V. Bulgakov, S. Nikolaenko, Z. Ruzhylo, I. Fedosiy, J. Nowak and J. Olt
Theoretical study on motion of potato tuber on surface of separator
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Theoretical study on motion of potato tuber on surface of separator

V. Bulgakov¹, S. Nikolaenko¹, Z. Ruzhylo¹, I. Fedosiy¹, J. Nowak² and J. Olt³

¹National University of Life and Environmental Sciences of Ukraine, 15 Heroyiv Oborony Str., Kyiv, UA03041, Ukraine
²University of Life Sciences in Lublin, 13 Akademicka Str., 20-950 Lublin, Poland
³Estonian University of Life Sciences, Institute of Technology, 56 F.R. Kreutzwaldi Str., EE51006 Tartu, Estonia
*Correspondence: jyri.olt@emu.ee

Abstract:

The aim of the study was to determine the optimal design and kinematic parameters of the separator that cleans potatoes from impurities and has a design of the spiral type. The authors have devised a highly efficient design of the spiral type potato heap separator, in which the motion of the potato tubers takes place in the channel formed by two spiral members made in the form of cylindrical spiral springs. In order to substantiate the optimal kinematic and design parameters of the new spiral type potato heap separator, the authors have generated a mathematical model of the motion of a single potato tuber on the cleaning surface formed by two spirals. As a result of solving the obtained analytical expressions, the graphical relations between the parameters of the investigated process of the motion of a single potato tuber body situated between two adjacent spirals have been plotted, which has enabled selecting the optimal design and kinematic parameters of the spiral separator. It has been established in the completed investigation that the angular velocity of rotation of the cleaning rolls has to be within the range of 27-40 rad s-1 in order to ensure the efficient transportation and cleaning of the potato tuber with a diameter of 50 mm that moves on the surface of the spiral with a radius of 75 mm wound from the round bar with a diameter of 15 mm, in case the spirals are mounted with an eccentricity of 10 mm. By analysing the kinematics of motion of the potato tuber on the surface of the spiral type cleaning machine, in case the tuber contacts the spirals at two points, it has been established that the increase of the angular velocity of rotation of the spirals results in the respective growth of the transportation capacity of the cleaning tool, while the separating efficiency at the same time becomes reduced to some extent.

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755–761 M. Daneček, M. Havrlík, V. Beránek, J. Šafránková, M. Libra, V. Poulek, J. Sedláček and R. Belza
Design and data comparison of the photovoltaic power plants in the southern and northern hemispheres
Abstract |
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Design and data comparison of the photovoltaic power plants in the southern and northern hemispheres

M. Daneček¹, M. Havrlík¹, V. Beránek², J. Šafránková¹*, M. Libra¹, V. Poulek¹, J. Sedláček¹ and R. Belza¹

¹Czech University of Life Sciences Prague, Kamýcká 129, CZ16500 Prague, Czech Republic
²Solarmonitoring, Ltd., Prague, Czech Republic
*Correspondence: janicka.safrankova@gmail.com

Abstract:

We have recently developed a unique monitoring system for photovoltaic power plants and have gradually improved it in recent years. The system is installed at about 80 power plants in several European countries and at one power plant in Chile. We collect and evaluate all data in our laboratory. In this paper we describe the unique design of a photovoltaic power plant in the southern hemisphere in Chile with photovoltaic panels installed on tracking stands. We present the evaluated data and we discuss their comparison with photovoltaic power plants installed in Europe. We also discuss different solar conditions of these locations.

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762–770 A. Dastpak, B.P. Wilson and M. Lundström
Investigation of the anticorrosion performance of lignin coatings after crosslinking with triethyl phosphate and their adhesion to a polyurethane topcoat
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Investigation of the anticorrosion performance of lignin coatings after crosslinking with triethyl phosphate and their adhesion to a polyurethane topcoat

A. Dastpak, B.P. Wilson* and M. Lundström

Aalto University, School of Chemical Technology, Department of Chemical and Metallurgical Engineering (CMET), Hydrometallurgy and Corrosion, Vuorimiehentie 2, P.O. Box 16200, Espoo, Finland
*Correspondence: ben.wilson@aalto.fi

Abstract:

This study investigates the anticorrosion properties of sustainable organic coatings, which were prepared by dissolution of two different types of technical lignins – organosolv lignin (OL) and kraft lignin (KL) – in an organic solvent and applied onto iron-phosphated steel by air-assisted spray coating. Influence of triethyl phosphate (TEP) as a crosslinking agent for lignin and its effect on the anticorrosion properties of coatings during 24 h of immersion in 3.5% NaCl were investigated. Results obtained from electrochemical impedance spectroscopy (EIS) of coated steels suggest that the initial protection performance (1 h immersion) of non-crosslinked OL is higher than that of KL. Nevertheless, KL coatings that contained TEP and were heat-treated at elevated temperature (180 °C) demonstrated the best overall anticorrosion performance. In contrast, a similar trend was not observed for OL coatings, which indicates that the structural properties of lignin may be a crucial factor in applicability of TEP as a crosslinking agent. In addition, a layer of polyurethane was applied on all the different types of lignin coatings prepared and their adhesion characteristics were studied by crosscut adhesion measurements (ISO 2409). These adhesion results revealed that neither KL-TEP nor OL-TEP coatings demonstrate proper adhesive characteristics with a polyurethane (PU) topcoat and consequently these coatings are not suitable for utilization as a primer coating for the PU topcoat studied.

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771–780 V. Denisova, K. Tihomirova, J. Neilands, K. Gruskevica, L. Mezule and T. Juhna
Comparison of phosphorus removal efficiency of conventional activated sludge system and sequencing batch reactors in a wastewater treatment plant
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Comparison of phosphorus removal efficiency of conventional activated sludge system and sequencing batch reactors in a wastewater treatment plant

V. Denisova*, K. Tihomirova, J. Neilands, K. Gruskevica, L. Mezule and T. Juhna

Riga Technical University, Research Centre for Civil Engineering, Water Research Laboratory, P. Valdena 1-204, LV-1048 Riga, Latvia
*Correspondence: viktorija.denisova@rtu.lv

Abstract:

The aim of this study was to evaluate the effectiveness application of sequencing batch reactors (SBRs) for phosphorus removal compared to the conventional activated sludge (CAS) treatment system. The results showed that the removal efficiency of phosphorus reached about 99% at wastewater treatment plant with CAS system. At the same time, the maximum phosphorus removal efficiency can be achieved to 88% if the SBRs system operating parameters are optimized. Finally, this study demonstrated that even if granules are not fully developed, the SBR system is working with a good efficiency.

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781–787 L. Dubova, N. Strunnikova, N. Cielava, I. Alsina, O. Kassien and A. Bekker
Thermal decontamination of sewage sludge
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Thermal decontamination of sewage sludge

L. Dubova¹*, N. Strunnikova², N. Cielava³, I. Alsina¹, O. Kassien⁴ and A. Bekker²

¹Latvia University of Life Sciences and Technologies, Faculty of Agriculture, Institute of Soil and Plant Sciences, 2 Liela street, LV-3001 Jelgava, Latvia
²Ekosoil Ltd, 26 Academy street, UA65009 Odessa, Ukraine
³Latvia University of Life Sciences and Technologies, Laboratory of Biotechnologies, 1 Strazdu street, LV-3004 Jelgava, Latvia
⁴Earth Revival, Ltd, Maskavas street 57-3, LV-1003 Riga, Latvia
*Correspondence: Laila.Dubova@llu.lv

Abstract:

Every year a huge amount of sewage sludge is formed at municipal wastewater treatment plants. Sewage sludge contains a sufficient amount of biogenic elements and organic components, which characterizes them as possible raw materials for the production of organic fertilizers. However, direct incorporation of these sediments into the soil is impossible due to the fact that, in addition to useful organic and mineral components, they contain pathogens, viruses and helminth eggs. The aim of the study was to optimise thermal disinfection conditions for preparing of safety sewage sludge fertilizer. Laboratory studies were carried out using sediments from wastewater treatment plants of some cities. During laboratory experiments, the conditions for thermal disinfection of sediments – the thickness of the sediment layer, the air temperature in the disinfection furnace, and the treatment time of the sediment – were determined. When conducting industrial tests of a conveyor-type sediment decontamination furnace, the operating conditions of the furnace were determined, i.e., the temperature regimes of the sludge heating zone, the decontamination zone and the cooling zone, and the optimum parameters of the sludge layer thickness on the conveyor and the conveyor speed were determined.

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788-796 B. Fagundes, F.A. Damasceno, R.R. Andrade, J.A.O. Saraz, M. Barbari, F.A.O. Vega and J.AC. Nascimento
Comparison of airflow homogeneity in Compost Dairy Barns with different ventilation systems using the CFD model
Abstract |
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Comparison of airflow homogeneity in Compost Dairy Barns with different ventilation systems using the CFD model

B. Fagundes¹, F.A. Damasceno²*, R.R. Andrade³, J.A.O. Saraz⁴, M. Barbari⁵, F.A.O. Vega⁴ and J.AC. Nascimento²

¹Professional Faculty, Department of Climatization Engineering, Porto Alegre, Tocantins Street, 937, n. 8, BR91.540.420 Porto Alegre, Brazil
²Federal University of Lavras, Department of Engineering, BR37200-000 Lavras, Minas Gerais, Brazil
³Federal University of Viçosa, Department of Agricultural Engineering, Av. Peter Henry Rolfs, s/n Campus University of Viçosa, BR36570-900, Viçosa, Minas Gerais, Brazil
⁴Univeridad Nacional de Colombia, Agrarian Faculty, Department of Agricultural and Food Engineering, Carrera 65 n. 59A – 110, Bloque 14 - Oficina 430, Medellin, Colombia
⁵University of Florence, Department of Agriculture, Food, Environment and Forestry, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: flavio.damasceno@ufla.br

Abstract:

In the pursuit of high milk productivity, producers are using confinement systems in order to improve performance and animal welfare. Among the housing systems, the Compost bedded-pack barns (CBP) stand out. In these barns a bedding area is provided inside, where cows move freely. Generally this area is covered with carbon source material (such as sawdust or fine dry wood shavings) which together with manure, thanks a regular mechanically stirring, ensures the aerobic composting process. The ventilation in these facilities has the function of dehumidifying the air, improving the air quality, drying the bedding, improving the thermal comfort conditions of the confined animals. This work aimed at validating a computational model using Computational Fluid Dynamics (CFD) to determine the best homogeneity of airflows generated by different forced ventilation systems used in CBP barns. Two CBP barns were compared with different ventilation systems: high volume low speed (HVLS) and low volume high-speed (LVHS) fans. The results showed that the proposed model was satisfactory to predict the flows generated by both types of fans. It was concluded that the use of HVLS fans produced a more homogeneous airflow when compared to LVHS fans. The use of mechanical ventilation in tropical conditions is necessary for the proper functioning of the system. In this study, the systems used promoted the increase in air speed to levels close to adequate.

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797-805 P.F.P. Ferraz, R.F. Mendes, G.A.S. Ferraz, V.R. Carvalho, M.R.C. Avelino, C.R.P. Narciso, T.M.C. Eugênio, V.G. Cadavid and G. Bambi
Thermal analysis of cement panels with lignocellulosic materials for building
Abstract |
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Thermal analysis of cement panels with lignocellulosic materials for building

P.F.P. Ferraz¹, R.F. Mendes², G.A.S. Ferraz¹, V.R. Carvalho², M.R.C. Avelino², C.R.P. Narciso³, T.M.C. Eugênio³, V.G. Cadavid⁴ and G. Bambi⁵

¹Federal University of Lavras, Department of Agricultural Engineering, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
²Federal University of Lavras, Department of Engineering, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
³Federal University of Lavras, Department of Forest Sciences, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
⁴Universidad Nacional de Colombia, Sede Medellin, Faculty of Agrarians Science, Medellín, Colombia
⁵University of Firenze, Department of Agriculture, Food, Environment and Forestry (DAGRI), Via San Bonaventura 13, IT50145 Firenze, Italy
*Correspondence: patricia.ponciano@ufla.br

Abstract:

The use of lignocellulosic material residue in cement composites can be considered as a good option because they allow good thermal behaviour. This paper aimed to compare three kinds of cement panels reinforced with different lignocellulosic materials (Coffee husk, Coconut shell, and Banana pseudostem) based on their thermal properties. To produce each panel, the methodology suggested by Souza (1994) was used. Six replicates of each lignocellulosic panel with dimensions of 7.0×7.5 were evaluated. The thermal analysis was performed in a chamber composed of MDP (medium density particleboard). The chamber contained the heat source (incandescent lamp) connected to a thermostat that maintained the temperature at 48.0 °C. The porosity and thickness of the panels and the thermal behaviour of each sample panel (thermal conductivity, resistivity, resistance, and transmittance) and the difference in temperature of both sides of the panel were evaluated. The temperature difference to stabilization was obtained after a sampling time of 200 minutes, with 1,000 readings of 12 s each. Although all the panels were submitted under the same temperature, the inner and external superficial temperatures of the coffee husk panels reached smaller values. Besides, coconut and banana pseudostem panels presented the best results of thermal transmittance and thermal resistance. Thus, coconut shell panels present the best thermal performance, which means that this panel might be an attractive alternative building material, in terms of heat insulation for indoor applications.

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806–814 P.F.P. Ferraz, R.F. Mendes, G.A.S. Ferraz, F.A. Damasceno, I.M.A. Silva, L.E.V.S.B. Vaz, L.M. Mendes, D. Cecchin and J.O. Castro
Comparison between the thermal properties of cement composites using infrared thermal images
Abstract |
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Comparison between the thermal properties of cement composites using infrared thermal images

P.F.P. Ferraz¹, R.F. Mendes², G.A.S. Ferraz¹, F.A. Damasceno², I.M.A. Silva², L.E.V.S.B. Vaz², L.M. Mendes³, D. Cecchin⁴ and J.O. Castro²

¹Federal University of Lavras, Department of Agricultural Engineering, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
²Federal University of Lavras, Department of Engineering, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
³Federal University of Lavras, Department of Forest Sciences, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
⁴Federal University Fluminense, Department of Agricultural Engineering and Environment, Campus Praia Vermelha, São Domingos, Niterói, Rio de Janeiro, Brazil
*Correspondence: patricia.ponciano@ufla.br

Abstract:

The use of agribusiness residual lignocellulosic fibres can be a good alternative in the development of lignocellulosic composites. The current work aimed to investigate the thermal performance of cement-based composites with lignocellulosic materials: Eucalyptus, sugarcane bagasse, coconut fibre in comparison with commercial gypsum board to be used as internal partitions of the building using infrared thermal images. Three repetitions for each kind of lignocellulosic material were made, and three commercial gypsum boards were used. In the production of the panels, the following parameters were applied: material and cement ratio, 1:2.75; water and cement ratio, 1:2.5; hydration water rate of 0.25; additive, 4% (based on cement mass). The calculations were performed for a nominal panel density of 1,200 kg m. The thermal analysis was performed in a chamber composed of MDP (Medium-Density Particleboard) and with an internal layer of rock wool and the heat source (thermal resistance). For the superficial temperature measurement, a FLIR E75 camera was used to capture the infrared images. When the internal temperature of the chamber stabilized at 50 °C, an infrared thermal image was collected from each side of the composite. Thermal properties were analysed: thermal conductivity, resistivity, resistance, and transmittance. Based on the results, sugar cane cement composites were characterized by higher values of thermal conductivity. Related to thermal resistivity, thermal resistance, and thermal transmittance, only the coconut panel presented similar behaviour to the commercial gypsum board. Thus, cement composite using coconut can be a potential alternative that might solve energy and environmental concerns simultaneously.

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815–822 P.F.P. Ferraz, R.F. Mendes, G.A.S. Ferraz, G. Rossi, L. Conti and M. Barbari
Chemical analyses of lignocellulosic materials residue for cement panels reinforcement
Abstract |
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Chemical analyses of lignocellulosic materials residue for cement panels reinforcement

P.F.P. Ferraz¹, R.F. Mendes², G.A.S. Ferraz¹, G. Rossi³, L. Conti³ and M. Barbari³

¹Federal University of Lavras, Department of Agricultural Engineering, Campus
Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
²Federal University of Lavras, Department of Engineering, Campus Universitário,
PO Box 3037, Lavras, Minas Gerais, Brazil
³University of Firenze, Department of Agriculture, Food, Environment and Forestry
(DAGRI), Via San Bonaventura 13, IT50145 Firenze, Italy

Abstract:

The use of lignocellulosic material residue in cement composites is on the rise as sustainable building materials in most developing countries. Besides, this alternative is seen as a good option for new cement panels formulations for indoor applications. Thus, the current paper aims to evaluate de chemical properties of five potential lignocellulosic materials residues to be used for cement panels reinforcement: Eucalyptus, sugarcane bagasse, coconut fibre, coffee rusk, and banana pseudostem. The following physical properties of the lignocellulosic materials were evaluated: lignin, extractives, ash, and holocellulose. To evaluate the similarity of the chemical composition of the lignocellulosic materials, Hierarchical Cluster Analysis (HCA) was used identified by using Ward’s method of cluster analysis. These compositions were grouped by dendrograms in which the similarity of these data was qualified. It was observed that there were statistical differences among all types of lignocellulosic materials related to the chemical composition. Coconut showed the smallest amount of extractives, and sugar cane the most significant amount. Eucalyptus and coffee husk presented the most similar chemical composition. All of the evaluated materials could be used in fibre cement production for indoor applications.

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823–841 M. Gailis, J. Rudzitis, M. Madissoo and J. Kreicbergs
Research on energy efficiency of pneumatic cylinder for pneumatic vehicle motor
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Research on energy efficiency of pneumatic cylinder for pneumatic vehicle motor

M. Gailis¹²*, J. Rudzitis¹, M. Madissoo³ and J. Kreicbergs¹

¹Riga Technical University, Faculty of Mechanical Engineering, Transport and Aeronautics, Institute of Transport, Kalku 1, LV 1658 Riga, Latvia
²Latvia University of Life Sciences and Technologies, Faculty of Engineering, Institute of Mechanics, Liela 2, LV 3001 Jelgava, Latvia
³Estonian University of Life Sciences, Institute of Technology, Fr. R. Kreutzwaldi 56/1, EE51014 Tartu, Estonia
*Correspondence: maris.gailis@rtu.lv

Abstract:

Compressed gas is relatively expensive source of energy. When compressed gas is used for propelling of pneumatically driven vehicle, efficient gas utilization is favoured. Design and control strategy of pneumatic cylinder, with the emphasis on effective energy conversion is being discussed in this paper. Mathematical model, results of computer simulation and experimental work are provided and discussed. Experimental research is performed on the competition vehicle, equipped with pneumatically driven piston motor and instrumented. Relative significance of various geometric and control parameters of pneumatic cylinder on efficiency of energy conversion is presented.

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842–851 P. Hnízdil, R. Chotěborský and J. Kuře
Utilization of fused deposition method 3D printing for evaluation of discrete element method simulations
Abstract |
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Utilization of fused deposition method 3D printing for evaluation of discrete element method simulations

P. Hnízdil¹, R. Chotěborský¹* and J. Kuře²

¹Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Science Prague, Kamycka 129, CZ165 00 Prague – Suchdol, Czech Republic
²Department of Electrical Engineering and Automation, Faculty of Engineering, Czech University of Life Sciences Prague, Kamycka 129, CZ165 21 Prague – Suchdol, Czech Republic
*Correspondence: choteborsky@tf.czu.cz

Abstract:

FDM 3D printing is used for designing prototype assessment in engineering production. It is usually used to verify the functionality of kinematics mechanisms. It can also be used for innovation in agricultural production, eg. the development of new mechanisms for agriculture tools. Such a mechanism as well as the entire components is printed using FDM and they are made of plastics. This whole can be experimentally verified in a laboratory trough. The article deals with the verification of the possibilities of using FDM technology for the design of agricultural tools. The material properties, namely stress-strain, of the plastics after printing are entered into the Ansys mechanical library, and the DEM results are also imported into Ansys mechanical. Material properties of plastics for FDM technology such as PLA, PETG show that its mechanical properties limited their using for validation.

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852–861 A.G. Ipatov, A.B. Spiridonov, R.R. Shakirov, A.V. Kostin, S.N. Shmykov and V.S. Kukhar
Physico-mechanical properties of modified antifriction coatings based on babbitt B83
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Physico-mechanical properties of modified antifriction coatings based on babbitt B83

A.G. Ipatov¹, A.B. Spiridonov², R.R. Shakirov³, A.V. Kostin³, S.N. Shmykov¹ and V.S. Kukhar⁴*

¹Operation and repair of machines, Izhevsk State Agricultural Academy, Studencheskaya steet 9, Izhevsk, Russia
²Technologies and equipment for food and processing industries, Izhevsk State Agricultural Academy, Studencheskaya steet 9, Izhevsk, Russia
³Theoretical mechanics and materials resistance, Izhevsk State Agricultural Academy, Studencheskaya steet 9, Izhevsk, Russia
⁴Ural State Agrarian University, Street Karla Libknekhta, 42, Ekaterinburg, Russia
*Correspondence: viktorurgau@mail.ru

Abstract:

The introduction presents the primary reasons for the decrease in the working efficiency of plain bearing assemblies and suggests key areas for the formation of a stable working capacity of these assemblies.
In addition, the introduction discusses preexisting methods for improving the working efficiency of plain bearings. These methods are based on the use of antifriction coatings and have the drawbacks which are considered in the text. The authors proposed a technology for producing an antifriction coating based on a metal composition. This antifriction coating is produces by high-speed laser processing of powder materials. The technology allows to create antifriction coatings, which have significant wear resistance and the effect of self-lubrication while also provide a minimum run-in time of the bearing assembly.
The methodology validates the choice of materials for the formation of an antifriction coating. An alloy with significant tribotechnical properties based on babbitt B83 was chosen as the basis (matrix). To improve the bearing capacity of the coating, the babbitt base was transformed with MoS2 molybdenum disulfide. The laser radiation usage in the formation of an antifriction coating based on babbitt B83 synthesizes finely dispersed intermetallide phases and forms a porous coating structure due to incomplete melting of the powder material. Molybdenum disulfide is released mainly through the porous structure, which leads to self-lubrication of the bearing assembly during oil starvation.
The results of microstructural and X-ray diffraction analysis are presented to display the structure of the obtained coatings based on antifriction materials. Research value is characterized by the presence of the following intermetallide phases in the structure of the formed coating: Fe2Sn, SnSb, Cu3Sn. The dispersivity of the formed phases is much greater than that of standard babbitt coatings, which is determined by higher crystallization rates under conditions of laser radiation processing. The analysis of diffractograms makes it possible to conclude that the distribution of intermetallide phases along the coating depth is uneven. The underlying layers close to the basis (matrix) are more soft and supple due to the presence of α – solid solution. The surface layers are solid and saturated with the finely crystalline Cu3Sn phase. The research undertaken on formed
coating under conditions of dry friction allows to conclude that the antifriction coating can work without supplying lubricant to the bearing assembly.

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862-887 H. Kaletnik, V. Mazur, I. Gunko, V. Ryaboshapka, V. Bulgakov, V. Raide, R. Ilves and J. Olt
Study on performance of compression engine operated by biodiesel fuel
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Study on performance of compression engine operated by biodiesel fuel

H. Kaletnik¹, V. Mazur¹, I. Gunko¹, V. Ryaboshapka¹, V. Bulgakov², V. Raide³, R. Ilves³ and J. Olt³*

¹Vinnytsia National Agrarian University of Ukraine, 3 Soniachna Str., UA21008 Vinnytsia, Ukraine
²National University of Life and Environmental Sciences of Ukraine, Ukraine, 15 Heroyiv Oborony Str., UA 03041 Kyiv, Ukraine;
³Estonian University of Life Sciences, Institute of Technology, 56 Kreutzwaldi Str., EE 51006 Tartu, Estonia
*Correspondence: jyri.olt@emu.ee

Abstract:

The analysis of the performance of biofuel is aimed at evaluating the energy efficiency of operating the engine with the use of biodiesel fuel as function of the fuel’s composition and other physical-and-chemical parameters. The mathematical models and analysis techniques known to the authors do not take into account the effect that the use of different bio-diesel fuels has on the operation of the engine and, therefore, need refinement in terms of the mathematical expressions and empirical formulae that describe the physical processes taking place in the engine’s cylinders. The aim of the study is to improve the mathematical relations taking into consideration the physical-and-chemical parameters of different types of fuel. The research methods proposed in the article are based on step-by-step consideration of the mathematical models of processes that follow each other, with due account for their possible overlapping, which jointly have an effect on the engine’s output indices. The boundary conditions and parameter increments are pre-set in electronic work sheets. Thus, it becomes possible, using the refined mathematical model, to calculate the main performance indices of the diesel engine with due account for the changes in the physical-and-chemical parameters of the fuel. The novelty of the described approach is in the possibility, through the use of the refined model and taking into account the data on the composition of the fuel and the design and operation parameters of the engine, to calculate the indices that allow evaluating the efficiency of use of specific fuels in the internal combustion engine under consideration. In results, formulas for the calculation of the effective power of the engine, fresh air charge density, excess air factor, effective specific fuel consumption and combustion pressure have been developed. Combustion pressure modelling and experimental data is presented.

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888-903 M. Khrapova, M. Růžička and V. Trnka
Recognition of retroreflective traffic signs by a vehicle camera system
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Recognition of retroreflective traffic signs by a vehicle camera system

M. Khrapova¹*, M. Růžička¹ and V. Trnka²

¹Czech University of Life Sciences Prague (CULS), Faculty of Engineering, Department of Vehicles and Ground Transport, Kamýcká 129, CZ165 00 Prague, Czech Republic
²ŠKODA AUTO a.s., tř. Václava Klementa 869, Mladá Boleslav II, CZ293 01 Mladá Boleslav, Czech Republic
*Correspondence: khrapova@tf.czu.cz

Abstract:

The systems of traffic sign recognition are based on the evaluation of three components of every sign: shape, colour and pictogram. There are different factors that can have an influence on the efficiency of detection and recognition of these components. One of the most important factors is the quality of the retroreflective sign surface. Retroreflective sheeting improves the readability of colour and pictogram of traffic sign by increasing brightness of its background and/or legend elements. The aim of the paper is to provide a comprehensive survey of the efficiency of sign’s recognition by a modern vehicle camera system. The traffic sign sheeting was measured by the handled retroreflectometer. Then this measurement was repeated by the modern camera system used for recognition of traffic signs in the vehicle. The results of this paper present the analysis of the recognition efficiency of traffic signs and the overview of other factors that can have a significant impact on sign detection and recognition distance. The results can be used for creation a traffic sign database for learning-based recognition techniques to vehicle camera systems.

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904–914 N.F. Luiz, D. Cecchin, A.R.G. Azevedo, J. Alexandre, M.T. Marvila, F.C. Da Silva, A.L.C. Paes, V.D. Pinheiro, D.F. Do Carmo, P.F.P Ferraz, C.M. Hüther, V.M.F. Da Cruz and M. Barbari
Characterization of materials used in the manufacture of ceramic tile with incorporation of ornamental rock waste
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Characterization of materials used in the manufacture of ceramic tile with incorporation of ornamental rock waste

N.F. Luiz¹, D. Cecchin¹*, A.R.G. Azevedo¹, J. Alexandre², M.T. Marvila², F.C. Da Silva¹, A.L.C. Paes², V.D. Pinheiro², D.F. Do Carmo¹, P.F.P Ferraz³, C.M. Hüther¹, V.M.F. Da Cruz⁴ and M. Barbari⁵

¹Federal Fluminense University (UFF), Engineering school, Department of Agricultural Engineering and Environment, Street Passo da Pátria, n.156, postal code: BR24210-240, Niterói, Rio de Janeiro, Brazil
²North Fluminense State University (UENF), Civil Engineering Department, Campos dos Goytacazes, Rio de Janeiro, Brazil
³Federal University of Lavras (UFLA), Department of Agricultural Engineering, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
⁴University of Évora, Polo da Mitra - Department of Rural Engineering - Évora/Portugal
⁵University of Firenze, Department of Agriculture, Food, Environment and Forestry (DAGRI), Via San Bonaventura 13, IT50145 Firenze, Italy
*Correspondence: daianececchin@yahoo.com.br

Abstract:

The production of ceramic tiles, such as tiles, has a great environmental impact, either in the extraction of natural raw materials or gas emissions in the burning stages. The use of industrial solid waste in ceramic materials can contribute to the reduction of these impacts, according to the characteristics of solid waste and its interaction with ceramic materials in the processing steps. Thus, this study aimed to characterize the materials needed to make a ceramic tile with incorporation of ornamental rock waste (ORW), thus evaluating its main characteristics regarding the feasibility of this incorporation. The physical characterization of the clays used in the production of ceramic artifacts was performed, and for the waste the mineralogical analyzes were performed, through x-ray diffraction (XRD), microstructure analysis from confocal optical microscopy, after sintering the prototypes and chemical analysis by X-ray spectroscopy (EDX). Soon after the raw materials went through the step of conformation and preparation of the prismatic specimens by the process of extrusion of the ceramic mass, with an incorporation of the ORW in 0% and 15% of the ceramic mass, for its subsequent The prototypes were sintered at three different temperatures (850 °C, 950 °C and 1,050 °C). The specimens were submitted to technological tests of mechanical resistance, water absorption, firing shrinkage and porosity to evaluate the incorporation viability. The results indicated the presence of quartz particles in all raw materials, and also that the clays of the study region are predominantly kaolinitic. The presence of these materials in the ceramic masses directly influences the micrographs, because they result in the formation of liquid phase, inert particles that can turn the site into a stress concentration point and when incorporated in the ORW the specimens met the technical specifications of the Brazilian standard for application on ceramic tiles. The results found in the technological tests carried out, that the incorporation of 15% of ornamental rock waste in both clays did not affect the tile properties, indicating the feasibility of incorporating this waste in civil construction, minimizing the impacts generated.

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915–922 D. Maksimov, H. Kalkis, Y. Perevoschikov and Z. Roja
Qualimetry as productivity criteria in metal-cutting operations
Abstract |
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Qualimetry as productivity criteria in metal-cutting operations

D. Maksimov¹*, H. Kalkis², Y. Perevoschikov¹ and Z. Roja³

¹Institute of Economics and Management, Udmurt State University, 1, Universitetskaya street, bld. 4, RU426034 Izhevsk, Russia
²Faculty of European Studies, Riga Stradins University, 16 Dzirciema street, LV-1007 Riga, Latvia
³University of Latvia, 19 Raina blv., LV-1586 Riga, Latvia
*Correspondence: maksim.dan.gen@gmail.com

Abstract:

The qualimetry method will allow an objective assessment of the performance of metal-cutting machines and the production capacity of machinery, as well as an objective assessment of their use in multi-product manufacturing, applying the qualimetry approach and qualimetry indicators, which are based on the concept of qualification of metal removing during machine operations. The aim of the study is to develop methods for measuring the performance of metal-cutting machines and open the way to create a regulatory framework based on quantitative indicators of the equipment quality. Qualimetry measured volume of metal removing allows setting the maximum possible productivity (quali-power) of metal cutting machinery, based on a small number of basic quality indicators contained in the machinery data sheets. It is essential that the quali-power of the machinery is an objective indicator of its quality, independent of the specific conditions of its operation at any given time. Hence the productivity criteria in metalworking cutting operations can be measured.

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923–930 V. Mitrofanovs, I. Boiko and Ē. Geriņš
New approach for recycling spare parts, components and assemblies
Abstract |
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New approach for recycling spare parts, components and assemblies

V. Mitrofanovs, I. Boiko and Ē. Geriņš

Riga Technical University, Institute of Mechanics and Mechanical Engineering, Kipsalas 6B, LV-1048 Riga, Latvia

Abstract:

Recycling and disposal are one of the most complicated topics in the lifecycle of a mechanism, especially in case of previous generations of machines that were designed without taking any care of post exploitation period. In the current work, the ‘feasibility points’ of recycling units, methods of recycling as well as pricing formation for recycling materials, reviewed and proposed by several world universities and scientific bureaus and applied by major world brands have been analysed. The general principles that should be rated as a basis when designing and creating new mechanisms, as well as the actions which we consider as a necessary supplement to the existing rules of the lifecycle of assemblies and which should be applied in practice, were introduced by authors in the ‘Management of parts and components for units and assemblies in mechanical engineering industry and its impact on the environment’. It was discovered that even modern assemblies, not to mention previous generations, are being designed without taking into consideration any possibilities of easy recycling the used materials. The number of components of mechanisms, which are being repaired as assemblies, is continuously increasing, while maintainability and repairability of separate parts is decreasing. Taking into account the state of the art in the field, the new approach for promoting the reusing natural resources and decreasing the harmful effects of obsolete components of mechanisms on the environment is proposed.
Thus, using the fast-moving parts that in post operational period can be easily detailed by type of a material will ensure more efficient consumption of natural resources. Our research and developments significantly reduce the costs of recycling and these materials become competitive comparing to the new ones.
Taking into account the state of the art in the field, the new approach for promoting the reusing natural resources and decreasing the harmful effects of obsolete components of mechanisms on the environment is proposed.

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931–944 F.A. Obando Vega, A.P. Montoya Rios, F.A. Damasceno, J.A. Osorio Saraz and J.A. Costa Do Nascimento
Airflow profile study of a compost dairy barn using a low-cost 3D-printed anemometer network
Abstract |
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Airflow profile study of a compost dairy barn using a low-cost 3D-printed anemometer network

F.A. Obando Vega¹*, A.P. Montoya Rios¹, F.A. Damasceno², J.A. Osorio Saraz¹ and J.A. Costa Do Nascimento²

¹Universidad Nacional de Colombia sede Medellín, Facultad de Ciencias Agrarias, Departamento de Ingeniería Agrícola y Alimentos, CO050034 Medellín, Colombia
²Federal University of Lavras, Department of Engineering, BR37200-000 Lavras, Minas Gerais, Brazil
*Correspondence: faobando@unal.edu.co

Abstract:

Mechanical ventilation is commonly used for environmental thermal regulation inside closed-field agricultural production systems. Analyzing the air distribution inside these facilities and the correct operation of the fans can be a challenging. This could be determined using cost prohibitive techniques as particle image velocimetry or deploying large wind sensors networks on-site. To avoid this limitation without a lack of measurement accuracy, this research was focused on developing and test a low-cost anemometer network based in low cost propeller’s anemometers, built using fused 3D-printed and open-hardware platforms. Four propeller anemometers with three to six blades were simulated using the 6-DOF method of ANSYS computer fluid dynamics software. Similar results were obtained for all the simulated models with minor differences. Anemometers were tested in an open circuit wind tunnel before to be evaluated in two open compost dairy barn building using high-volume low-speed and low-volume high-speed fans. Data were analyzed by employing contour maps, descriptive statistics and correlation. The results show that the anemometer network determines the fan’s wind profile for wind speeds over 0.7 m s-1 and it was possible to determine the facilities spots with ventilation problems. The proposed anemometer network and methodology are a good alternative to analyze the operating conditions of the tested agricultural facilities and optimize its performance.

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945–957 D. Pastare, Z. Roja, H. Kalkis and I. Roja
Psychosocial risks analysis for employees in public administration
Abstract |
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Psychosocial risks analysis for employees in public administration

D. Pastare¹, Z. Roja¹, H. Kalkis¹²* and I. Roja³

¹University of Latvia, Ergonomics Research Centre, Raina blvd. 19, LV-1586 Riga, Latvia
²University of Latvia, Faculty of Business, Management and Economics, Department of management, Aspazijas blvd. 5, LV-1050 Riga, Latvia
³MFD Healthcare group, Vienibas gatve 109, LV-1000, Riga, Latvia
*Correspondence: henrijs.kalkis@gmail.com

Abstract:

Nowadays psychosocial risks at work have a serious impact not only on the health of employees, but also on the economic performance of organisations, and this is the biggest challenge in working environment. In Latvia, employees in public administration comprise 11% of the total population. Hence the aim of this study was to analyse the causes of psychosocial risks and the differences in their prevalence among inspectorate officials employed in the State Administration compared to office staff employed by the State Administration. A modified Copenhagen Psychosocial Questionnaire from the Danish National Research Centre for the Working Environment was used to assess psychosocial risks at work. One public administration organisation was selected for the study, which involved 111 staff (60 inspecting officers and 51 office staff). The analysis of the results of the psychosocial risk assessment shows that there are statistically significant differences in the assessment of four out of 11 psychosocial risks to the working environment. The most common psychosocial work environment risk factor among inspectors is the inadequate attitude of management, but the most common risk factor among office employees is the lack of impact on work. To reduce the spread of psychosocial risks more effectively, an individual approach is required for each worker.

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958–968 H. Pihlap, A. Annuk, M. Lehtonen, S. Muiste, A. Tooming and A. Allik
A control method for increasing the heat usage efficiency of nearly-zero-energy buildings with heat pumps
Abstract |
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A control method for increasing the heat usage efficiency of nearly-zero-energy buildings with heat pumps

H. Pihlap¹*, A. Annuk¹, M. Lehtonen², S. Muiste¹, A. Tooming¹ and A. Allik¹

¹Estonian University of Life Sciences, Institute of Technology, Chair of Energy Application Engineering, Kreutzwaldi 56, EE51006 Tartu, Estonia
²Aalto University, Department of Electrical Engineering and Automation, Maarintie 8, Espoo, Finland
*Correspondence: heino.pihlap@emu.ee

Abstract:

In the retrofitting of older buildings with central heating into nearly zero-energy buildings more and more air to water heat pumps are used. These heat pumps are normally connected to heating systems, producing heat only on demand. The greatest demand for heat occurs when the outside temperature and therefore the COP of the pump is lowest. Outside temperature varies during the day, meaning it is possible to save energy by producing and storing heat in a situation where the COP is higher. To determine the periods with higher COP values weather forecast data and COP curves are used. The data enables to rank and select time periods for heat production. This in conjunction with the heat demand curve of the building enables to create an operation schedule for the heat pump. The aim of the study is to develop heat pump control methods for renovated buildings to comply with nearly zero energy building codes. Dependent on the heat pump and weather conditions, up to 10 % of the electricity demand for heating can be decreased.

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969–979 A. Ryabchikov, M. Kiviste, S.-M. Udras, M. Lindpere, A. Vassiljev and N. Korb
The experimental investigation of the mechanical properties of steel fibre-reinforced concrete according to different testing standards
Abstract |
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The experimental investigation of the mechanical properties of steel fibre-reinforced concrete according to different testing standards

A. Ryabchikov, M. Kiviste, S.-M. Udras, M. Lindpere, A. Vassiljev and N. Korb

Estonian University of Life Sciences, Institute of Forestry and Rural Engineering, Chair of Rural Building and Water Management, Kreutzwaldi 1, EE51006 Tartu, Estonia
*Correspondence: alexander.ryabchikov@emu.ee.

Abstract:

Steel fibre-reinforced concrete (SFRC) is widely applied in the construction of civil infrastructure projects, including the following: industrial floors, slabs, walls, and foundations. The application of steel fibres in the reinforcement of concrete remarkably improves the post-cracking behaviour of such concrete. In order to estimate this property, the energy involved in absorption is measured by using several valid testing standards: EVS-EN 14651:2005, EVS-EN 14488-5:2006, and ASTM C1550-12a. The objective of this study was to carry out a comparable analysis of the results that have been obtained using previously-mentioned standards and to be able to find a more reliable method for the determination of the fracture toughness of SFRC specimens. Experiments were carried out in accordance with the chosen standards. It was concluded that procedure involved in the ASTM standard provides a smaller variability of results with better levels of repeatability, therefore a smaller volume of specimens can be tested in one series in order to achieve reliable results.

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980–988 E.O. Samuilova, A.V. Podshivalov, M.I. Fokina, V.S. Chursina, I.E. Strelnikova and M.V. Uspenskaya
Tensile properties of wood plastic composites based on plant-filled polyvinyl chloride/poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) matrices
Abstract |
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Tensile properties of wood plastic composites based on plant-filled polyvinyl chloride/poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) matrices

E.O. Samuilova*, A.V. Podshivalov, M.I. Fokina, V.S. Chursina, I.E. Strelnikova and M.V. Uspenskaya

ITMO University, Faculty of Applied Optics, Kronverkskiy pr., 49, RU197101 Saint Petersburg, Russia,
*Correspondence: samuilova.eo@itmo.ru

Abstract:

The article considers the obtaining and studying of microcomposites based on polyvinyl chloride (PVC)/poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) polymer matrix, filled with a various faction of different natural plant fillers. In work, such plant fillers as wood flour without lignin, spruce flour and rice husk were used. Microcomposites were obtained by melt rolling processing method with subsequent analysis of their morphology and mechanical tensile properties. It is shown that the filler particles were strongly oriented in the direction of the melt rolling process and have a different aspect ratio depending on the filler type. The tensile strength of materials strongly depends on the particle’s aspect ratio. When the aspect ratio of the particles is 4.25, the material has a strength value comparable to a pure PVC/PHBHHx matrix.

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989–999 T. Schlechter, R. Froschauer and A. Bronowicka-Schlechter
Towards a business and production engineering concept for individual beer brewing applying digitalization methodologies
Abstract |
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Towards a business and production engineering concept for individual beer brewing applying digitalization methodologies

T. Schlechter¹*, R. Froschauer¹ and A. Bronowicka-Schlechter²

¹University of Applied Sciences Upper Austria, Automotive Mechatronics and Management, Stelzhamer str. 23, AT4600 Wels, Austria
²Salzburg Schokolade GmbH, Hauptstraße 14, AT5082 Grödig, Austria
*Correspondence: thomas.schlechter@ieee.org

Abstract:

Individualization is a common trend in many fields of production across the industries. Also in the food sector, significant changes can be observed. For many products, individual offerings towards the customer are meanwhile either mandatory or at least help to increase the sales and revenue. Somehow, individual product design and production contradicts scaling effects, which are especially important for food production. On the other hand, as digitalization is implemented in a fairly limited way in the food sector, currently great chances can be observed to build a unique selling proposition and consequently gain market share by implementing appropriate measures to enable a digital food factory. This is where the proposed idea comes into the game. The starting point is the idea to produce individually developed beer and ship it to the individual customer. The beer can be designed on a web page based on typical parameters, like beer type, bitterness, colour, or alcohol concentration. In an expert mode, individual beer creations may be thoughtful, allowing the creation of completely individual recipes (for sure, not guaranteeing the customer a perfect drinking experience). In any way, the data from the web page is directly fed to the brewing equipment in the brewing facility. There, using newly to be developed specialized machines, the individually ordered beer will be produced automatically. In this paper we discuss the individual challenges at each point in the production cycles and propose solutions to those.

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1000–1009 L. Šenfelde, D. Kairiša and D. Bārzdiņa
Effect of concentrate feeding technology on nutrient digestibility in Latvian Dark-Head lambs
Abstract |
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Effect of concentrate feeding technology on nutrient digestibility in Latvian Dark-Head lambs

L. Šenfelde, D. Kairiša and D. Bārzdiņa

Latvia University of Life Sciences and Technologies, Faculty of Agriculture, Institute of
Animal Science, Street Liela 2, LV-3001 Jelgava, Latvia

Abstract:

Research has been conducted to evaluate the effect of concentrate feeding technology on nutrient digestibility in Latvian Dark-Head lambs. Twenty-four purebred Latvian Dark-Head lambs (rams) were divided into three study groups (four lambs in each group). Concentrate was offered with different feeding technologies: group 1 – ad libitum once per day (ADL); group 2 – five times per day (5TD); group 3 – three times per day (3TD). Lamb live weight at the start of research was 24.6 kg (ADL), 24.1 kg (5TD) and 25.6 kg (3TD), the average age – 83 ± 1.4 days (ADL; p < 0.05), 75 ± 1.4 days (5TD) and 75 ± 1.6 days (3TD). Research data were collected over three periods and two repetitions during lamb fattening in July, August and September, 2019. During the data collection period lambs were transferred to cages with slatted wooden floor and a container with a grid under it. The highest concentrate intake in all data collection periods was found in ADL lambs (1.25 ± 0.106 kg – 1.75 ± 0.092 kg on average per lamb). Hay intake was not equal (90–350 g in average per lamb).The highest average faecal production was found in 3TD and 5TD lambs (F – 0.98 ± 0.102 kg (3TD), S – 1.13 ± 0.060 kg (5TD) and T – 0.99 ± 0.070 kg (5TD)).The least urinal production was found in 3TD lambs (0.24 ± 0.038 kg (F), 0.61 ± 0.078 kg (S) and 0.47 ± 0.033 kg (T)). Dry matter digestibility was 66.54–80.39%. Faecal consistency was soft for ADL and 5TD lambs and solid for 3TD lambs.

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1010–1017 T. Seregina, O. Chernikova, Yu. Mazhaysky and L. Ampleeva
Features of the influence of copper nanoparticles and copper oxide on the formation of barley crop
Abstract |
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Features of the influence of copper nanoparticles and copper oxide on the formation of barley crop

T. Seregina¹, O. Chernikova¹*, Yu. Mazhaysky¹ and L. Ampleeva²

¹Academy of law management of the federal penal service of Russia, Sennaya street 1, RU390036 Ryazan, Russia
²Ryazan State Agrotechnological University named after P.A. Kostychev, Kostychev street 1, RU390044 Ryazan, Russia
*Correspondence: chernikova_olga@inbox.ru

Abstract:

In addition to modern methods of agricultural technology, currently the achievements of selection and genetics are widely used, as well as modern nanotechnology and nanomaterials, to improve food production. One of the forms of biologically active nanomaterials is metal nanopowders and their derivatives. The application is carried out in minimal doses that can significantly reduce costs in agricultural production. Improving the yield and quality of crops by optimizing nutrition and plant protection using nanotechnology and nanomaterials will solve not only the problems of increasing the yield and quality of farmed products, but also environmental problems. The purpose of this research was to determine the effect of copper and copper oxide nanoparticles on the formation of a barley crop. Under the conditions of a lysimetric experiment, the effect of presowing treatment of spring barley seeds by nanoparticles of copper and copper oxide on the growth and development of plants, yield, and their nutritional value was studied. The used nanoparticles have the following characteristics: Cu – 40–60 nm, phase composition: Cu – 100%; CuO – 40–60 nm, phase composition: CuO – 100%. A suspension of nanoparticles was obtained by dispersion by ultrasound in an aqueous solution. Nanopowders of copper and copper oxide in the solution contained 0.01 g per hectare seed rate. Barley seeds were soaked 30 minutes before sowing in double distilled water (control variant), as well as in a suspension of nanoparticles. Presowing treatment of barley seeds by Cu nanoparticles contributed to the intensification of growth processes, as well as an increase in green mass. The use of copper nanoparticles contributed to an increase in grain yield by 17.3% compared with the control, while there was no decrease in nutritional value: metabolic energy, feed units, digested protein. Based on the research results, it is preferable to use copper nanoparticles in comparison with copper oxide nanoparticles to obtain a higher barley yield.

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1018-1026 K.L. Silva-Martínez, L. Cruz-Rivero, A. Arrieta-González and R. Purroy-Vasquez
Non-Invasive measurer for methane and carbone dioxide emissions in bovine cattle through TRIZ
Abstract |
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Non-Invasive measurer for methane and carbone dioxide emissions in bovine cattle through TRIZ

K.L. Silva-Martínez¹, L. Cruz-Rivero¹*, A. Arrieta-González¹ and R. Purroy-Vasquez²

¹TECNM/ ITS-TANTOYUCA, Posgrado e Investigación, Desv. Lindero Tametate SN Col. La Morita CP 92100, Tantoyuca, Veracruz, México
²TECNM /ITS- Zongolica, Posgrado e Investigación, Km 4 Carretera a la Compañia S/N, Tepetliplanapa, CP 95005, Tantoyuca, Veracruz, México
*Correspondence: lilirivero@gmail.com

Abstract:

Greenhouse gases (GHG), mainly methane (CH4) and carbon dioxide (CO2), can be generated in agricultural activities, not only in waste but also in the process of breathing of livestock. The Theory of Inventive Problem Solving (TRIZ) is an innovative Russian methodology that allows finding the solution to a problem raised. This paper presents the use of two TRIZ tools to design a non-invasive prototype that detects CH4 and CO2 emitted by cattle in real time. The tools were the matrix of technical contradictions and the nine-screen analysis with which the parameter to be improved (A) was found and the best possible solution to design a prototype that allows quantifying gases for animal welfare, Final Ideal Result (IFR) a wireless module with a sensor system for each of the gases placed on the bovine head, which convert the detected gas into an electrical signal to be sent wirelessly to a range of 1.5 km in free space at a receiver for its visualization representing the parts per million (ppm) of CH4 and CO2 that the bovine is generating during the measurement.

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1027-1035 R. Šmigins, V. Pīrs and D. Berjoza
Investigation in fuel consumption of a hybrid and conventional vehicle
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Investigation in fuel consumption of a hybrid and conventional vehicle

R. Šmigins*, V. Pīrs and D. Berjoza

Latvia University of Life Sciences and Technologies, Faculty of Engineering, Motor Vehicle Institute, J. Cakstes blvd 5, LV3001 Jelgava, Latvia
*Correspondence: ruslans.smigins@llu.lv

Abstract:

During the last decade the introduction of more environmentally friendly technologies were raised more rapidly by the decline in the global fossil energy resources and the increased negative environmental impact of conventional vehicles. One of such technology is the hybrid, which is currently making the transition from conventional vehicle with internal combustion engine to an electric vehicle. At this time there exist a lot of offers of such vehicles from different manufacturers, but there do not exist many researches connected with real hybrid performance in different road cycles and conditions allowing evaluate its real economical performance.
This research was realized with the aim to evaluate performance and fuel consumption of hybrid electric vehicle and its conventional internal combustion engine analogue in laboratory conditions. Tests were realized with two new Toyota Yaris vehicles in Alternative Fuels and Research Laboratory on chassis dynamometer MD-1750 using AVL KMA Mobile system. The results showed better adaptation of Toyota Yaris Hybrid to urban operation, demonstrating 21.3% lower fuel consumption than Toyota Yaris conventional gasoline vehicle, accordingly 7.29 and 8.84 L (100 km)-1.

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1036-1045 J. Sosnowski, K. Jankowski, M. Truba, J. Novák, E. Zdun and J. Skrzyczyńska
Morpho-physiological effects of Stymjod foliar application on Dactylis glomerata L.
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Morpho-physiological effects of Stymjod foliar application on Dactylis glomerata L.

J. Sosnowski¹*, K. Jankowski¹, M. Truba¹, J. Novák², E. Zdun¹ and J. Skrzyczyńska¹

¹Siedlce University of Natural Sciences and Humanities, Prusa street 14, PL-08110 Siedlce, Poland
²Slovak University of Agriculture in Nitra, Tr. A. Hlinku street 2, SK94976 Nitra, Slovakia
*Correspondence: jacek.sosnowski@uph.edu.pl

Abstract:

The aim of the experiment was to study the effects of foliar application of a growth regulator containing iodine nanoparticles, with the trade name of Stymjod, on morphometrics, photosynthetic activity and chlorophyll content of Dactylis glomerate L. The following parameters were determined: the weight of fresh and dry matter of plants, leaves and roots, the number of shoots and leaves, potential (FV/Fm) and effective (ΔF/Fm’) quantum efficiency of photosystem, photochemical (qP) and non-photochemical (qN) quenching, as well as chlorophyll a and chlorophyll b content in leaf blades. The pot experiment was carried out in a breeding room. Stymjod was applied at 1.5%, 3% and 4.5% concentrations in the spray solution. It is a nanotechnology-based growth regulator, with easily assimilable forms of mineral and organic ingredients, favorably affecting plant ontogenesis. Plants were treated twice with a single dose of 50 mL of spray per pot. They were sprayed till they were completely covered with the liquid. Distilled water was used to spray control plants. The results were statistically processed using analysis of variance, while the significance of the differences between means was determined with Tukey’s test with P = 0.05. In the experiment it was found that different concentrations of Stymjod in the spray resulted in different response of plants. The best morphological effects were obtained using the concentration of the product exceeding 3%. In the test conditions Stymjod applied to D. glomerata increased the efficiency of the photosynthetic apparatus and the content of chlorophyll pigments.

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1046-1055 I. Tipans, J. Viba, M. Irbe and S.K. Vutukuru
Investigation of dual varying area flapping actuator of a robotic fish with energy recovery
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Investigation of dual varying area flapping actuator of a robotic fish with energy recovery

I. Tipans, J. Viba, M. Irbe and S.K. Vutukuru

Riga Technical University, Faculty of Mechanical Engineering, Transport and
Aeronautics, Department of Theoretical Mechanics and Strength of Materials,
Kipsala street 6B, LV-1048 Riga, Latvia

Abstract:

Autonomous under-water vehicles (AUV) performing a commanded task require to utilize on-board energy sources. At the time when on-board power source runs low during operation, the vehicle (AUV) is forced to abort the mission and to return to a charging station. The present work proposes the technique of an energy recovery from surrounding medium. This effect is studied for dual action actuator movement that obtains energy from fluid. It is realized that a flapping or vibrating actuator can be used for energy extraction phenomenon apart from the non-traditional propulsive technique. In the present work a simple dual flapping actuator that can switch between simple flat plate and perforated plate at extreme end positions (angles) by using an efficient mechatronic mechanism that would help in overcoming viscous forces of the operating medium is extensively studied. The main objective of the present article is to develop a new approach for energy gain and recharge power pack of on-board sources from the surrounding medium and to create a robotic fish that would work autonomously by using unconventional drive along with the possibility of energy restoration by using dual varying area type vibrating actuator. At the time of recharge, the robotic fish would project its tail (actuator) out of water and use surrounding medium (air) to scavenge the energy. All the equations describing the process are formed according to classical laws of mechanics. The mechatronic system is explained and the results obtained are discussed in detail for air as the operating fluid to scavenge energy.

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1056-1067 A. Traumann, V. Urbane, J. Ievinš and P. Tint
The Co-influence of Noise and Carbon Dioxide on Humans in the Work and Living Environment
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The Co-influence of Noise and Carbon Dioxide on Humans in the Work and Living Environment

A. Traumann¹, V. Urbane², J. Ievinš² and P. Tint³*

¹Tallinn University of Applied Sciences, Institute of Clothing and Textile, Pärnu mnt. 62, EE10135 Tallinn, Estonia
²Riga Technical University, Faculty of Engineering Economics and Management, Institute of General and Civil Safety, Kalnciema 6, LV-1048 Riga, Latvia
³Külasema Village Society, EE94744 Muhu, Saaremaa, Estonia
*Correspondence: info@piiatint.ee

Abstract:

The aim of the paper is to investigate the co-influence of noise and carbon dioxide on people in different situations (inside/outside houses/classrooms) depending on the traffic intensity, the fuel used for heating in residential buildings etc.). All the measurements and the questionnaire have been carried out during the autumn of 2019 (at the mean temperature of 5–10 °C). Riga has a more intensive traffic compared to Tallinn and has greater problems of exceeding the permissible noise levels. The levels of carbon dioxide inside classrooms are also very high in Latvia (1,500–2,000 ppm). The concentration of carbon dioxide outside buildings is low in the forest areas (measured in the south of Estonia), being 340–350 ppm. In regional towns, it is 500 ppm (measured in autumn-winter near a busy street). The co-influence of noise and carbon dioxide on the residents has been investigated by using the Weinstein questionnaire. High carbon dioxide levels cause fatigue. Although it was not particularly pointed out by the residents questioned in a panel house with small apartments, the air was considered to be stuffy. The house is situated near a busy street, so the problems with noise are higher. ANOVA statistics has been used for the questionnaire (p < 0.001, α = 0.93). The decrease of noise and carbon dioxide levels help people stay healthy and the environmental impact from the investigation is emphasising the necessity and providing possibilities to decrease the concentration of CO2 in the ambient air.

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1068–1081 M.O. Vilela, R.S. Gates, S. Zolnier, M. Barbari, C.G.S. Teles Junior, R.R. Andrade, K.S.O. Rocha, I.F.F. Tinôco, C.F. Souza, L. Conti and G. Rossi
Variable velocity system for evaluating effects of air velocity on Japanese quail
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Variable velocity system for evaluating effects of air velocity on Japanese quail

M.O. Vilela¹*, R.S. Gates², S. Zolnier¹, M. Barbari³*, C.G.S. Teles Junior¹, R.R. Andrade¹, K.S.O. Rocha¹, I.F.F. Tinôco¹, C.F. Souza¹, L. Conti³ and G. Rossi³

¹Federal University of Viçosa, Department of Agricultural Engineering, Av. Peter Henry Rolfs, s/n Campus University of Viçosa, BR36570-900 Viçosa, Minas Gerais, Brazil
²Iowa State University, Departments of Agricultural and Biosystems Engineering, and Animal Science, Egg Industry Center, 1202 NSRIC, Ames, IA 50011, USA
³University of Florence, Department of Agriculture, Food, Environment and Forestry,
Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: monique.vilela@ufv.br; matteo.barbari@unifi.it

Abstract:

This study documents the design and performance of a system to apply different magnitudes of air velocity to Japanese quail, to evaluate the combined effects of velocity, temperature and humidity on bird behaviour, performance and welfare. The system was developed to simulate observed field conditions occurring in regions with high winds where quail are raised in curtain-sided housing. System performance consisted of characterizing air velocity distribution in cages downstream of the air velocity which was directed at the front of the cages. The system consisted of two fans attached to a 25 cm PVC tube, one at each end, with the outlet airflow directed through a continuous slot over the cage front at the feeder. The design and performance of this experimental system was evaluated, with six such systems were built and utilized in research trials. To assess system performance, air velocity was measured at 275 points per cage uniformly arranged along the three dimensions (length, width and height) in eight cages with zero, 1, 2 or 3 m s-1 nominal velocity setpoints. Spatial distribution of velocity was analysed by mapping and from descriptive statistics, with attention to the zone closest to the feeder where birds must go to eat. There was no significant difference (P > 0.05) found in mean paired difference of air speed data measured for pairs of front portion cages with similar velocities. A significant positive correlation was found (P < 0.001) between the measured air velocity at paired points in the cages subjected to the same velocity treatment. A comparison of measured mean air velocity to the nominal setpoint values used for experiments indicated that careful attention to outlet adjustment is important, especially at higher nominal velocity setpoint as 3 (± 0.10) m s-1 which was difficult to achieve with the system. An example of the use of the deployment of the variable velocity system in controlled environment chambers with Japanese quail is provided.

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1082–1089 J. Vošahlík and J. Hart
Reliability of camera systems to recognize facial features for access to specialized production areas
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Reliability of camera systems to recognize facial features for access to specialized production areas

J. Vošahlík¹* and J. Hart²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Constructions, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Vehicles and Ground Transport, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: vosahlik@oikt.czu.cz

Abstract:

The article deals with ergonomics and reliability of camera systems for recognition of facial features and identify person for access to specialized areas. The monitoring of areas relates not only to crime, but it is also an integral part of access to specialized production areas (pharmaceutical production, chemical production, specialized food production, etc.). It is therefore important to adequately secure these premises using the relevant system. One of them is a system based on user identification using specific facial features. For this purpose, there are CCTV systems for recognition of facial features of different price categories (conventional cameras, semi-professional and professional) on the world market. However, problematic situations may occur when identifying. For example, by having the user partially masked face. This research is focusing on the problem. The main goal of the research is establishing the scale of negative impact, in case the identified person has partially masked face, on camera systems recognizing facial features, primarily on recognition time. The results are evaluated in detail. Some camera systems are not suitable in specialized production areas due to their insufficient recognition ability. From all the tested devices, the HIKVISION iDS-2CD8426G0 / F-I camera identification system has proved to be optimal for identification purposes. In the case of designing, it is therefore necessary to choose suitable camera systems that have ergonomics and reliability at a level that will guarantee their sufficient use in the mentioned areas, while decreasing comfort and user-friendliness as little as possible. By measuring the ergonomics and reliability of these CCTV systems, it can be stated that there are statistically significant differences between conventional, semi-professional and professional systems, and it’s not just a design change, but also a more efficient recognition method.

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1090–1098 V. Vtoryi, S. Vtoryi and V. Gordeev
Hydrogen sulfide emissions from cattle manure: experimental study
Abstract |
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Hydrogen sulfide emissions from cattle manure: experimental study

V. Vtoryi*, S. Vtoryi and V. Gordeev

Federal State Budgetary Scientific Institution ‘Federal Scientific Agroengineering Center VIM’, Filtrovskoje shosse, 3 p.o. Tiarlevo, Saint Petersburg, RU196625, Russia
*Correspondence: vvtoryj@yandex.ru

Abstract:

Animal waste products, manure, in particular, are the sources of gases harmful to human and animal health. Hydrogen sulfide (H2S), which is produced from the breakdown of organic matter in animal faeces, is one of them. Its concentration in the cow barn air should not exceed 5 mg m−3. A special laboratory setup was designed and the level of hydrogen sulfide emissions from the cow manure was determined depending on the time and manure temperature and moisture content. The most intensive emission of hydrogen sulfide from manure was in the first 24 hours – the increment of H2S concentration was 0.168 mg m−3 per hour average. During the next 24 hours, it was 0.021 mg m−3 per hour. When the manure temperature increased, H2S concentration increased also; when the temperature manure decreased, H2S concentration decreased also. In 48 hours, the hydrogen sulfide concentration was 1.1 mg m−3 at the manure temperature of +3.0 °C. At the manure temperature of +23.4 °C and 21.3 °C, H2S concentration was 6.53 mg m−3 and 4.97 mg m−3, respectively. The higher was the manure moisture content, the lower was the emission of hydrogen sulfide into the environment. After 24 hours under the manure moisture content of 88.5% and 92.5% and its temperature of 21 °С ± 0.3 °С, the difference in the hydrogen sulfide concentration was 1.18 times depending on the manure moisture content. The selected regression equations described the dependence of the hydrogen sulfide concentration on the considered factors. The determination coefficients and Student’s criteria proved the reliability of the results obtained at the significance level P ≤ 0.05.

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1099–1106 A.R.P.P. Weerasuriya Arachchige, L. Mezule and T. Juhna
Separation of reducing sugars from lignocellulosic hydrolysate: Membrane experiments & system dynamic modelling
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Separation of reducing sugars from lignocellulosic hydrolysate: Membrane experiments & system dynamic modelling

A.R.P.P. Weerasuriya Arachchige*, L. Mezule and T. Juhna

Riga Technical University, Faculty of Civil Engineering, Department of Water Science and Technology, Paula Valdena street 1-204/205, LV-1048 Riga, Latvia
*Correspondence: antonrayan@hotmail.com

Abstract:

Separation of fermentable sugars after hydrolysis of lignocellulosic biomass plays a vital role in second-generation biofuel production. Byproducts and solid fractions generated during pretreatment and hydrolysis can have adverse effects on fermentation efficiency. Previous studies have shown that a maximum of 40% (w/w) of sugar yield can be obtained by sequential UF and NF permeate recovery. This study aimed to introduce a multi-step membrane filtration process to recover fermentable sugars while removing inhibitory bi-products. Fermentable sugar recovery was investigated using a recirculation flow between various stages of separation. The experimental results demonstrated that by introducing NF permeate recirculation to the UF unit a sequential UF/NF system can achieve 60% (w/w%) recovery of reducing sugars. Based on the experimental results, a ‘Simultaneous ultrafiltration and nanofiltration model’ was developed using system dynamics. The model was used to predict the final sugar concentration and sugar yield using sugar permeability in each membrane as the dynamic variability. The model predicts that high sugar permeability (or selective permeability) through the ultrafiltration mostly affects the efficiency of the system, which still is a challenge.

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