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Determination and Optimization of Feeding Device Parametres in the Plant for Preparing Liquid Feed Mixtures
2021
Solonshchikov, Pavel | Savinykh, Peter | Ivanovs, Semjons
Feeding young animals is a very important stage during their growing-up period, but in order to provide them with essential nutrients, they are fed with liquid feeds, whole milk substitute in particular (WMS). The technique for reconstituting WMS consists of dissolving it in water followed by mixing, but it is significant to follow the cooking recipe strictly, so it is necessary to develop a system with a feeding (dosing) device that will make it possible to solve this problem. Theoretical and experimental studies of the feeding device have been conducted in order to optimize the technological process of mixing liquid feed. Theoretically, the quality of determining the mixture during dosing was established for the purpose of further research. The influence of the design and technological parameters of the feeding device was experimentally studied, and its efficiency was evaluated. It was found that as the inclination angle α increases from 67,5⁰ to 70⁰, the rotation speed n being from 850 to 1500 min⁻¹, the maximum probability of staying in the tolerance field ΔP=96% is reached, and feed discharge Q ranges from 540 to 660 kg h⁻¹. The research makes it possible to develop a feeding device at the design stage, meeting the requirements of the recipe, having high discharge rates and the lowest energy consumption.
Afficher plus [+] Moins [-]The Comparative Efficiency Analysis of EU Members Agriculture Sectors
2017
Laurinavičius, Eligijus | Rimkuvienė, Daiva
Production economics forms a very important part of an enormous range of economic theory. Agricultural production is no exception. When evaluating the competitiveness of the multifunctional agriculture, it is necessary to use the measure of efficiency instead of productivity. The conception of the efficiency is explained and the methods for measurement are provided. The authors discuss the methods of Stochastic Frontier Approach (SFA), Free Disposal Hull (FDH) and Data Envelopment Analysis (DEA) that are particularly useful for multi-criterial evaluation of multifunctional processes. Those methods assign an efficiency score to each Decision Making Unit (DMU) based on how well it transforms a given set of inputs into outputs. Most studies have only focused on application of DEA method for assesment of the efficiency of agriculture farms. There is still a need on applications for sectors. This paper provides an examination of the applicability of DEA method to agriculture sectors efficiency measurement. By applying mathematical models, which are based on the DEA, the efficiency of agriculture in each EU country was evaluated.
Afficher plus [+] Moins [-]Strategic Potential of Agricultural Waste as a Feedstock for Biofuels Production in Ukraine
2021
Tokarchuk, Dina | Pryshliak, Natalia | Shynkovych, Andrii | Mazur, Kateryna
Ukraine’s agriculture is a leading sector of the national economy. Ukraine has a significant area (603628 km²), 70.9% of which are agricultural lands. Quality soil and good climatic conditions create favorable conditions for the development of crop and livestock production. The generation of a large amount of organic waste from agriculture opens wide opportunities for the development of the biogas technologies. The aim of the paper is to identify the main waste management trends in Ukraine based on data on waste generation and waste management and to calculate the strategic potential of agricultural waste as a feedstock for biofuels production. The resource potential of crop, livestock and processing waste has been considered and the necessity of its use for energy purposes has been substantiated. It has been determined that the greatest potential of agricultural waste that can be used for biogas production in Ukraine is concentrated in crop production. The livestock industry and processing enterprises also have a powerful feedstock base for biogas production. It has been determined that the agroindustrial sector of Ukraine produces significant amount of waste. As a result of the study, it has been found that the potential volume of biogas production from agricultural waste can replace 36.1% of natural gas consumption in Ukraine.
Afficher plus [+] Moins [-]Determination and optimization of feeding device [parameters] in the plant for preparing liquid feed mixtures
2021
Solonshchikov, P., Vyatka State Agricultural Academy, Kirov (Russian Federation) | Savinykh, P., Federal Agrarian Scientific Centre of the North-East named after N.V. Rudnitsky, Kirov (Russian Federation) | Ivanovs, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Feeding young animals is a very important stage during their growing-up period, but in order to provide them with essential nutrients, they are fed with liquid feeds, whole milk substitute in particular (WMS). The technique for reconstituting WMS consists of dissolving it in water followed by mixing, but it is significant to follow the cooking recipe strictly, so it is necessary to develop a system with a feeding (dosing) device that will make it possible to solve this problem. Theoretical and experimental studies of the feeding device have been conducted in order to optimize the technological process of mixing liquid feed. Theoretically, the quality of determining the mixture during dosing was established for the purpose of further research. The influence of the design and technological parameters of the feeding device was experimentally studied, and its efficiency was evaluated. It was found that as the inclination angle α increases from 67,50 to 700, the rotation speed n being from 850 to 1500 minE−1, the maximum probability of staying in the tolerance field ΔP=96% is reached, and feed discharge Q ranges from 540 to 660 kg hE−1. The research makes it possible to develop a feeding device at the design stage, meeting the requirements of the recipe, having high discharge rates and the lowest energy consumption.
Afficher plus [+] Moins [-]The efficiency of different wood coatings against water surface absorption
2021
Iejavs, J., Forest and Wood Products Research and Development Inst., Ltd., Jelgava (Latvia) | Ruluks, O., Forest and Wood Products Research and Development Inst., Ltd., Jelgava (Latvia) | Laiveniece, L., Forest and Wood Products Research and Development Inst., Ltd., Jelgava (Latvia) | Jakovlevs, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pugovics, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Lise, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Spulle, U., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
In the market of the Latvia different wood surface coating materials suitable for use in outdoor conditions are offered, but available information on the efficiency of these against direct water exposure is insufficient. For structural timber building elements, such as glued laminated timber (GLT), the surface coating should be applied taking into account technological, visual or colour changes (ISO 7724:1984) and – last, but not least – economic aspects are considered. Wood surfaces coated with coating materials, such as varnishes, paints, etc. can stabilize some properties such as movement of moisture content, dimensional changes and attack by microorganisms and fungi. The changes in the moisture content of timber may influence such important parameters as mechanical properties and the total life time of the structural timber elements. A study has been conducted with the aim of assessing the efficiency of coating materials used for wood protection against water absorption. In this study, six different commercial coating products used for the treatment of spruce (Picea Abies L. Karst.) and pine (Pinus Sylvestris L.) samples were tested. The efficiency of different coating substances was assessed using two modified test methods according to the standards EN 382-2 (1994) and EN 927-5 (2006), determining the surface water absorption after immersion in water for 24 h and the dynamics of water absorption of the glued laminated timber for 696 h kept in water. As a result of the study, it has been ascertained that organic solvent-based commercial coating products are more efficient against short-term and long-term wood water absorption compared to oil-based coating materials.
Afficher plus [+] Moins [-]The effect of separated expansion chamber parameters on exhaust pressure oscillations in single cylinder motorcycle engine
2020
Banis, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia). Faculty of Engineering
This paper investigates the effect of separated exhaust expansion chamber parameters on pressure oscillations in spark-ignited internal combustion (IC) gasoline engines. It is known that exhaust expansion chambers are becoming increasingly more popular among both – original equipment (OE) and aftermarket equipment (AE) exhaust system manufacturers for performance-oriented motorcycles equipped with mainly single cylinder engines, but the companies are reluctant to reveal any detailed principles of operation of the mentioned expansion chambers. The subject of this research is the type of expansion chamber (separate) as used on performance-oriented motorcycles, particularly its’ effect on exhaust pressure pulsations as different chamber volumes, locations and passage sizes are tested. Time-dependent computational fluid dynamics (CFD) analysis was carried out in Solidworks Flow Simulation environment on a simplified exhaust header pipe model imitating engine operation at full load and steady speed. Honda CRF450R motorcycle engine was used as the example and fully defined using a 1D engine performance calculator software to determine the combustion chamber pressure and exhaust valve lift at any given crankshaft position. Volume flow rate of exhaust gasses at the header pipe inlet was calculated based on engine parameters and operating speed. The average pressure values with respect to physical time were measured and graphed across the header pipe inlet cross-section. Eight different header pipe and exhaust expansion chamber combinations were modelled, tested, and results compared at low, medium and high engine speeds. It was found that the presence of exhaust expansion chamber tends to dampen the amplitude and decrease the frequency of pressure oscillations generated at the opening of the exhaust valve(s). Observations show that the addition of an expansion chamber as per design of performance-oriented motorcycles helps to decrease the negative effect of engine tuning while also dampening the positive effect.
Afficher plus [+] Moins [-]Research support model for improving the effectiveness of medical study data collection
Balina, Signe | Salna, Edgars | Kojalo, Ilona | Avotina, Eliza
The paper describes the research support model for improving the effectiveness of the medical research data collection process and data quality. Every research project involves a data collection phase, during which different organisation, legal and technology factors are involved, including various procedures (questionnaire design, annotation, database design, data entry, data validation, discrepancy management, medical coding and data mining). The key task of clinical data management is to obtain high-quality data, which can be achieved by minimising data input errors and timely identifying missing data. This process is often time-consuming and takes up a significant part of the research project budget in both veterinary and human medicine. The aim of this study is to elaborate the research support model for the creation of a data collection automation software tool, which will allow one to ensure better data quality, shorten the time for data collection and minimise human work volume and respective human resource expenses, making research projects more effective in terms of their timing and budget. Research work included analysis of the current situation, its shortcomings, typical research project budget distribution and existing automated electronic data collection tools (EDC). Research was carried out in partnership with the Institute of Clinical and Preventive Medicine of the University of Latvia.
Afficher plus [+] Moins [-]The comparative efficiency analysis of EU members agriculture sectors
2017
Laurinavicius, E., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Rimkuviene, D., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Production economics forms a very important part of an enormous range of economic theory. Agricultural production is no exception. When evaluating the competitiveness of the multifunctional agriculture, it is necessary to use the measure of efficiency instead of productivity. The conception of the efficiency is explained and the methods for measurement are provided. The authors discuss the methods of Stochastic Frontier Approach (SFA), Free Disposal Hull (FDH) and Data Envelopment Analysis (DEA) that are particularly useful for multi-criterial evaluation of multifunctional processes. Those methods assign an efficiency score to each Decision Making Unit (DMU) based on how well it transforms a given set of inputs into outputs. Most studies have only focused on application of DEA method for assessment of the efficiency of agriculture farms. There is still a need on applications for sectors. This paper provides an examination of the applicability of DEA method to agriculture sectors efficiency measurement. By applying mathematical models, which are based on the DEA, the efficiency of agriculture in each EU country was evaluated.
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