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Kaunas, Lithuania

Aleksandras Stulginskis University is a university in Lithuania, in Akademija, west of Kaunas. It was renamed from Lithuanian University of Agriculture in 2011. Wikipedia.

Balezentiene L.,Lithuanian University of Agriculture
Allelopathy Journal

Assessment of the total phenols content (TPC) and biochemical impact of H. sosnowskyi on perennial ryegrass (monocots) and winter rapeseed (dicots) seed germination was done ex situ. Aqueous extracts of 2-yr old H. sosnowslyi exhibited higher phytotoxicity than 1-yr. old plant extracts. The phytotoxic effects of H. sosnowskyi aqueous extracts on the germination depended extract concentration (0.02- 0.2%), plant age (1-year, 2-year), plant parts (shoot: stem, leaf, blossom, seed; root) and growth stage (rosette-ripening). The phytotoxicity of H. sosnowskyi determined extract was most strong at flowering stage due to highest TPC (30.42 mg ml-1). All parts of H. sosnowskyi produced phenolics, which inhibited the acceptor-species seed germination. The results suggested that invasive plant species may acquire spreading advantage in new territories through use of their allelochemicals to inhibit germination. Nonetheless, species evidence for allelopathic effects should not be restricted to analysis of the plant extracts in the lab, but also include research in natural environment. Source

Buksnaitis J.,Lithuanian University of Agriculture
Elektronika ir Elektrotechnika

The investigation of electromagnetical efficiency of the two-layer preformed six-phase winding is presented. At first the variation of phases of the six-phase windings was determined and, on the basis of the theory of three-phase windings, the development of the electrical circuit of the analyzed winding was formed. In order to determine the harmonic spectrum of rotating magnetomotive force created by the six-phase winding the instantaneous space function of rotating magnetomotive force was formed by using the created circuit and instantaneous values of the phase currents in the moment of time t = 0. The harmonic analysis of this function was performed and according to its results the electromagnetical efficiency factor of the analyzed six-phase winding was calculated. The obtained factor was compared to the electromagnetical efficiency factor of the two-layer preformed three-phase winding of analogous parameters and it was determined that it is 8,64 % higher than in the three-phase winding case. Additionally it was obtained that the amplitude value of the fundamental harmonic of rotating magnetomotive force of the analyzed six-phase winding is 1,983 times higher that the amplitude value of rotating magnetomotive force of the analogous three-phase winding. This means that the power factors of the alternating current electrical machines with the six-phase windings should be notably higher compared to the three-phase machines. Ill. 2, bibl. 8, tabl. 5 (in English; abstracts in English and Lithuanian). Source

Streimikiene D.,Vilnius University | Balezentis T.,Lithuanian Institute of Agrarian Economics | Balezentiene L.,Lithuanian University of Agriculture
Renewable and Sustainable Energy Reviews

The aim of the paper is to assess energy technologies in road transport sector in terms of atmospheric emissions and costs and to indicate the most competitive and environmentally friendly transport technologies. The main tasks of the paper are: to develop the multi-criteria framework for comparative assessment of energy technologies in road transport and to apply MCDM methods for the transport technologies assessment. One of the MCDM methods, viz. the interval TOPSIS method, is employed in order to tackle the uncertain criteria. The assessment framework allows comparing road transport technologies in terms of their environmental and economic impacts and facilitates decision making process in transport sector. The main indicators selected for technologies assessment are: private costs and life cycle emissions of the main pollutants (GHG; particulates, NOx, CO, HCs). The ranking of road transport technologies based on private costs and atmospheric emissions allowed prioritizing these technologies in terms of environmental friendliness the lowest costs. However the extent, capacity, and quality of road infrastructure affects the overall level of transportation activity, which in turn affects how much energy is consumed by vehicles and the amount of greenhouse gases (GHG) emitted. The paper presents the impact of transportation infrastructure on GHG emissions from road vehicles and policy implications of performed assessment. © 2012 Elsevier Ltd. Source

Raslavicius L.,Lithuanian University of Agriculture | Bazaras T.,Kaunas University of Technology

In this article, diverse liquid biofuels of the first generation were compared as partial or infant substitutes for fossil diesel fuel applied in cogeneration plant of the average capacity of 340 kW. The study concentrates on agricultural and economic conditions as well as legislative basis distinctive to Lithuania. At the laboratory of the Lithuanian University of Agriculture Institute of Agro-Engineering an experimental diesel engine powered generator was fuelled with rapeseed oil methyl ester (pure and in the blend with fossil diesel and dyed diesel fuels) and rapeseed oil with excellent energy balances and emissions characteristics more favorable than fossil diesel. Detailed estimations were proposed in order to assess the economic feasibility of complementing renewable electricity and heat generated in the final output cycle. The carried out analysis showed, that good perspectives are forecasted for using diesel engines in cogeneration plants, if they run on rapeseed oil produced by farmers themselves. The operation of such a plant would realize 184960 € of annual income for sold electricity, allowing to pay annual depreciation expenses and exceed the production cost for thermal energy to be 0.033 €/kW h. This price lies under the established one by the centralized energy suppliers, accordingly 0.058 €/kW h. © 2010 Elsevier Ltd. Source

Balezentiene L.,Lithuanian University of Agriculture | Streimikiene D.,Mykolas Romeris University | Balezentis T.,Lithuanian Institute of Agrarian Economics
Renewable and Sustainable Energy Reviews

Both strategic and environmental factors make biomass an important energy source and element of sustainable energy policy. The establishment of a reasonable energy crop-mix, indeed, involves various uncertain data. This paper, therefore, offers a multi-criteria decision making framework for prioritization of energy crops based on fuzzy MULTIMOORA method which enables to tackle imprecise information. Given the appropriate energy crop-mix should exhibit both climatic suitability and low environmental pressure, we have defined the indicator set covering respective linguistic and numeric indicators. Accordingly, the set of alternatives were constructed from energy crops suitable for the Lithuanian climate. The fuzzy MULTIMOORA method was employed for data fusion and prioritization. As a result, the prospective species for energy crop-mix were suggested. © 2012 Elsevier Ltd. Source

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