Mašinų elementų konstravimo ypatumai

Vytauto Didžiojo universitetasŽemės ūkio akademij

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Household income consists of two income streams labor income and capital income and exhibits heterogeneity due to the different income structure, through income change dependency on the state of the economy or through reliance to different industry or employee entity. The bottom income households as well as the top income ones displays the highest income sensitivity to the business cycle changes. Thus, aggregate household income change sensitivity to GDP growth (or stock market returns), called GDP beta, is U-shaped with males and younger workers being more exposed to earning risk sensitivity that females and older ones. Workers for construction, durable manufacturing industries are more exposed to economic cyclicality while those working for the financial industry has the highest aggregate risk exposure. Apart of systemic risk observed in earning sensitivity to GDP changes the residual part of regression also exhibits components of systemic risk across of its idiosyncratic nature. More specifically, implied systemic risk defined by the size of the employer: workers for larger employer are less exposed to aggregate risk, but they more exposed to employer-level earnings risk. Those observations achieved by running regressions through U.S. data sets was interesting to verify using Lithuanian household income sensitivity to external factors, such as GDP change and others. However Lithuanian household income structure differs in a sense of labor income predominance. Capital market is less matured and financial literacy of Lithuanian population is still shallow what keeps retails investment and capital gain generation at low level. Therefore, measuring Lithuanian household income sensitivity to external factors only wage changes were taken into consideration. Another drawback of Lithuanian household income sensitivity analysis was the shortage of reliable data for GDP time series, as official sources allow data set for 10 years period only. So, a linear regression OLS GDP β estimator equitation model was run and reveals evidence of those conclusions: Lithuanian household income sensitivity to GDP changes curve is mildly U-shaped, with lower tail of low-level income being almost irresponsive to GDP changes. This might be explained by state regulation of setting the minimum wage level, representing political will rather than income change sensitivity to economic cycles. GDP beta distribution curve is very flattish in Lithuania household case, demonstrating relatively low sensitivity of income changes to economic growth for those whose earnings are distributed to the middle of the. This might be explained by the fact, that the main industry mostly contributing to GDP growth is retail and wholesale. Likewise, this industry exhibits weak income sensitivity to economic cyclicality in U.S. case, therefore the parallel of explaining Lithuanian shape of GDP beta curve flattish-ness sounds quite reasonable. Finally, Lithuanian household income sensitivity to the changes of the state of the economy is upward sloping at the top-level income distribution. Although financial industry in Lithuania is not that sound like in U.S. case, nonetheless incomes those working in financial industry prevail at the 90th to 100th percentile across income distribution curve in both cases

The Analysis of Manure Distribution Evenness on Hilly Soil

Almost 52 % of agricultural landed property is composed of very hilly, hilly and rolling salience. The dynamics of mineral manure distribution depending on slope lean angle of the hilly field has been studied. The analytic dependencies of initial particle velocity, the angle of particle discharge from the disc and flying distance on the disc lean angle of the spreader on slope. Due to slope lean manure particles fly different distances from the symmetry of the spreader to opposite directions. It was determined that slope lean angle (its negative and positive values) has differed impact on transverse distribution of manure. The negative value of the angle has less influence on the particle flying distance than the positiveVytauto Didžiojo universitetasŽemės ūkio akademij

Thermal weed control in strawberry

Weed control with herbicides is impossible in perennial organic agricultural systems. Alternatively, in these systems, weeds can be destroyed mechanically, thermally or by mulching with a plastic film, to minimize negative weed influence, but not to exterminate all of them. Thermal weed control requires knowledge of the plants' thermal sensitivity. The most common weeds growing between strawberry rows in Lithuania are shepherd's purse (Capsella bursa), common groundsel (Senecio vulgaris L.) and common chick-weed (Stellaria media). We have been researching thermal sensitivity of these weeds. Research has shown the results of preheating a 2-mm diameter weed stem up to 70°C: shepherd's purse (Capsella bursa) 2.0 s., common groundsel (Senecio vulgaris L.) - 2.4 s. and common chick-weed (Stellaria media) 1.7 s. Weeds between rows were burned as mechanical control is not allowed when strawberries are flowering. To estimate the effectiveness of this method, when thermal weed sensitivity was researched, the unit speed was selected depending on the degree of weed developmentVytauto Didžiojo universitetasŽemės ūkio akademij

Research of Influence Green Fertilizer Mulching for a Crop of Potatoes and Structure of Ground

Bulvių pasėlių, muičiuotų 10 cm gyliu sideraciniais augalais, piktžolėtumas, lyginant su mėšlu tręštais, būna 2,3-8 kartus mažesnis. Lysvėse dirvą purenant akmenų separatoriais, į paviršių iškeliamos piktžolių sėklos ir šakniastiebiai, kurie dėl saulės poveikio žūva, ir lauko piktžolėtumas sumažėja 2,3 karto. Lysvėje, mulčiuotoje žaliąja trąša, grumstelių mažesnių negu 10 mm, kiekis buvo 67,2 %, o kontroliniame variante tik 57,4 %. Didžiausia bulvių kero masė buvo dirvoje, mulčiuotoje žaliąja trąša ir prieš sodinimą supurentoje akmenų separatoriumi, o mažiausia nemulčiuotoje, tradiciniu būdu ir akmenų separatoriumi purentoje dirvoje. Akmenų separatoriumi purentos dirvos prieš bulvių kasimą 0-18 cm sluoksnio kietis buvo 200 kPa mažesnis, lyginant su kontroleReplacement of dung with green fertilizer mulching to a depth of 10 cm decreased weed growing 2.3 to 8.0 times. Rotor horizontal cultivators, and in stony soil - stone and clod collectors, concentrate weed rootlets in the surface of springtime hoed soils. Exposed to the sun, the amount of perennial weeds decreases in potato furrows 2.3 times. Owing to a crushing device for 5-7 cm stone fractions, installed in stone collectors, weeds decreased 3.4 times. Combined units for lumpy and stony soil preparation for potato growing were developed and studied. These units are employed to make widened and deepened technological paths and loose soil beds. Special equipment for planting and bed-smoothing was designed. Growing potatoes in beds ensures more effective application of liquid complex fertilizers, watering during dry periods, suppressing the weeds by potato tops in narrowed inter-rows and, consequently, reducing pollution. The widened technological paths are sown with short under-crops of insecticide, fungicidal or phytoncidal effect. The above mentioned methods permit to develop an ecologically friendly potato growing technology and experimental equipment for itVytauto Didžiojo universitetasŽemės ūkio akademij

Influence of dynamical factors on safe work with a fertilizer spreader

The efficiency of mineral manure most often depends on the evenness of its distribution. The dynamics of the spread of the particles of the mineral manure in regard to the fixed and variable parameters of the imitative model of the spreader have been analyzed. The programmable location of a particle on soil depends on the movement trajectory of the particle on the disc and in the air, which eventually determine the final distribution of particles. The research considered the flow of the manure particles from the spread opening of the manure-box, the trajectory on the disc and in the air, the place of a particle on the surface of the ground as well as on how these trajectories depend on the characteristics of the spreader and particles. The trajectory of particle in the air is the function of its initial velocity and direction, by which the particle leaves the surface of the disc. It determines the final place of the particle on the surface of soil with respect to disc. One of the accidental factors influencing the trajectory of a particle is the impact of spreader lean on hilly soil on the discharge angle of manure particles and the distance of particle fly in the distribution sector. The dependence of the spreading distance of the manure particles on the initial speed of the particle and the trajectory angle of a disc has been obtained. It was established that when the aggregate moves, the trajectory angle changes due to the roughness of the ground from the one that was set constructively up to the largest value when a particle flies farthest. Under the influence of random factors, the angle between the spreader's disc plane and a plane of soil surface can increase up to 8 degrees; therefore the distance of particle's wafting increasesVytauto Didžiojo universitetasŽemės ūkio akademij

Исследование динамики разбрасывания минеральных удобрений

Bibliogr.: p. 197 (4 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij

Management the evenness of the spread of particles with efferent spreaders

Vytauto Didžiojo universitetasŽemės ūkio akademij

Влияние полосового мульчирования на биометрические параметры моркови

Bibliogr.: p. 238 (2 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij