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The paper presents the results of research aimed at the verification of the existing design solutions of four example sowing units for agricultural seed drills with the most frequently used types of sowing wheels. The research was conducted with the use of modern computer simulation systems based on the discrete element method (DEM) with the evaluation of the efficiency of selected design solutions in terms of achieved performance and metering uniformity. The paper includes a description of virtual research models and the employed mathematical models used for mirroring contact between seeds. Moreover, for the purpose of verification of the obtained results, bench tests were conducted using actual models of selected design solutions.

In the article design of a self-propelled vehicle for inspecting ventilation ducts and ceiling structures in buildings equipped with omni wheels was presented. Such vehicles are used in places that are hard to reach for people. The vehicle was designed using the vehicle control system – ARDUINO. For this system dedicated program was written, which is used to operate it. The vehicle is remotely controlled by radio waves. Its range is about 100 meters and the power supply is a 12 V battery. The vehicle operator has joysticks (controllers) modelled on those used in game controllers that are used for precise vehicle control. The vehicle is equipped with cameras that allow to view the image in real time. The omni wheels have also been tested for strength by the finite element method (FEM). Carried out FEM analysis as part of the work allowed to determine the strength of omni wheels on the acting forces during vehicle movement.

Cultivators are machines used among others to open and smooth out the surface of the ploughland and to mix mineral fertilizers with soil. The article presents a design of a cultivator mounted on an agricultural tractor with a power of up to 20 kW. The main design assumption mainly focuses on keeping the weight of the device low, while ensuring the required durability. Moreover, the design makes it possible to attach it to the three-point linkage in a category 1 tractor. The drafted design was subjected to the MES analysis, according to which, the maximum travel of the cultivator frame does not exceed 1.3 mm, and the stress typically reaches the level of 40 MPa and does not exceed the stress permissible for the E295 steel. An analysis of the costs of manufacturing the cultivator was also performed and on its basis, it was found that the price should not exceed PLN 1,800.

The main purpose of the performed works was to develop a concept of a bulldozer blade mounted to the road roller. The paper presents the main assumptions, design stages, results of strength analyses of the blade, which can be used in a road roller. Because the elements that push the components of machines operating on construction sites, in mines and in the agricultural environment, the elaborated element would enable wider use of the roller. Based on the FEM analyses, it has been confirmed that the developed load bearing structure is characterized by full operating strength. The designed blade meets the initial assumptions and can be used as equipment of heavy machines.

The aim of our paper is to identify explanatory variables for income disparities between women and men across different regional types. Using data from the BA Employment Panel (BEP) descriptive statistics show that the gender pay gap grows wider from core regions to periphery. The main explanatory variables for the income differentials are vocational education in the men's case and size of enterprise in the women's case. Whereas in the case of women the importance of vocational status increases and the importance of size of enterprise decreases from rural areas to urban areas.

This paper presents the design and implementation of device for remote and automatic monitoring of temperature field of large objects. The project aimed to create a quadcopter flying platform equipped with a thermal imaging camera. The object of the research was district heating installations above ground and underground. The results of the work on the implementation of low-cost (below 750 EUR) and efficient heat loss monitoring system. The system consists of a small (

Technology of wind exploitation has been applied widely all over the world and has already reached the level in which manufacturers want to maximize the yield with the minimum investment outlays. The main objective of this paper is the determination of the optimal number of blades in the Cup-Bladed Vertical Axis Wind Turbine. Optimizing the size of the Vertical Axis Wind Turbine allows the reduction of costs. The maximum power of the rotor is selected as the performance target. The optimum number of Vertical Axis Wind Turbine blades evaluation is based on analysis of a single blade simulation and its superposition for the whole rotor. The simulation of working blade was done in MatLab environment. Power spectrum graphs were prepared and compared throughout superposition of individual blades in the Vertical Axis Wind Turbine rotor. The major result of this research is the Vertical Axis Wind Turbine power characteristic. On the basis of the analysis of the power spectra, optimum number of the blades was specified for the analysed rotor. Power spectrum analysis of wind turbine enabled the specification of the optimal number of blades, and can be used regarding investment outlays and power output of the Vertical Axis Wind Turbine.

Se evaluó el nivel de conocimiento de la nueva Ley de bosque nativo y fomento forestal que poseen los pequeños propietarios forestales en dos territorios de la Cordillera de Nahuelbuta, en Chile. Para ello, se aplicó una encuesta a 53 personas (10% de las viviendas), que abordó cinco temas centrales: (1) uso del bosque nativo, (2) participación en redes sociales y acceso a la información, (3) conocimiento general de la Ley, (4) conocimiento respecto a la administración y (5) fomento de la Ley. Los resultados mostraron que: (1) el bosque nativo es usado para obtener productos madereros y no madereros, (2) las redes sociales y especialmente la radio son fundamentales para la transferencia de información, (3) tanto el conocimiento general de la Ley como (4) el nivel de conocimiento respecto de la administración de la Ley es insuficiente, y (5) se desconocen los trámites que deben efectuarse para obtener los beneficios de la Ley. Se concluye que: (1) el nivel de conocimiento de la Ley es insuficiente, (2) es fundamental estimular el uso de los instrumentos de esta Ley en la totalidad del territorio, de modo de garantizar el uso sustentable del recurso, y (3) la difusión de los beneficios de la Ley debe considerar las formas de comunicación tradicionales, el nivel de educación y la cultura de los espacios rurales

This paper is about cataracting motion in a rotating drum. The research was carried out for three types of filling. A PIV program - which allows to determine the local velocity field and particles trajectory - was applied to define the filling behaviour. Experimental and calculated (by the Oyama equation) results have been compared. An attempt to revision of implemented model notation have been undertaken, so that a better description of start- and final-cataracting motion will be achieved.

Following the general tendency of miniaturization of devices in many branches of industry, smaller and smaller components are used. Mini channels are used to construct mini heat exchangers and mini reactors. Because of this fact, predicting two-phase pressure drops along the mini tube plays an important role already at the design stage. It defines the proper and safe operating conditions of such devices. It was decided to research this phenomena in five single mini channels and undertake a comparison of various correlations models reported in literature and check how the process of changing critical Reynolds value affects the conformity of the experimental data and results reported in literature. It was found that the Mishima-Hibiki model derived from literature offers the possibility of most accurate mathematical modelling. It was also found that changing critical Reynolds value because of mini channel roughness can significantly improve the accuracy of the existing correlations models e.g. for Lee-Lee model the improvement is equal to almost 9%.

ABSTRACT: The Poços de Caldas Alkaline Massif, located in southeast Brazil, is composed of tinguaites, as well as phonolites and nepheline syenites (NeS), together with assorted pyroclastic rocks. The latter constitute deposits within the Vale do Quartel, and show fragments of alkaline rocks (NeS, tinguaites), basaltic and ultramafic volcanics/subvolvanics, sandstones, and quartz-feldspathic rocks from the crystalline basement. NeS fragments with melanite, previously unknown, and cm-sized fragments of phlogopite megacrysts from related conduit breccia were chosen for detailed studies. The NeS fragments are medium- to coarse grained and contain K-feldspar (Or 95-83 ), secondary albite (Ab 97 ), altered nepheline, clinopyroxene (diopside, minor hedenbergite) and partially altered, zoned, idiomorphic melanite. These NeS fragments are typically metaluminous, and point to the existence of similar intrusions hidden at depth, an important input to the massif’s petrology. The phlogopite megacrysts are compositionally homogeneous, with high Ti, Mg and Al contents; Ba and F are minor components. Two phlogopite aliquots were dated and yielded identical 40 Ar/ 39 Ar plateau ages of 87.1(± 0.5) Ma and 86.6(± 0.5) Ma, which represent minimum and maximum values for phlogopite crystallization and breccia emplacement, respectively. Previously obtained ages for the Poços de Caldas rocks are concentrated in the 75-86 Ma range interval.

The Fernando de Noronha Archipelago presents, on its main island, a centrally-located stratigraphic unit, the Remédios Formation (age around 8 - 12 Ma) constituted by basal pyroclastic rocks intruded by dikes, plugs and domes of varied igneous rocks, capped by flows and pyroclastics of mafic to ultramafic rocks of the Quixaba Formation (age around 1 - 3 Ma), which is limited from the underlying unit by an extensive irregular erosion surface. A predominant sodic Remédios series (basanites, tephrites, tephriphonolites, essexite, phonolites) can be separated from a moderately potassic Remédios sequence (alkali basalts, trachyandesites, trachytes), both alkaline series showing mostly continuous geochemical trends in variation diagrams for major as well as trace elements, indicating evolution by crystal fractionation (mainly, separation of mafic minerals, including apatites and titanites). There are textural and mineralogical evidences pointing to hybrid origin of some intermediate rocks (e.g., resorbed pyroxene phenocrysts in basaltic trachyandesites, and in some lamprophyres). The primitive Quixaba rocks are mostly melanephelinites and basanites, primitive undersaturated sodic types. Geology (erosion surface), stratigraphy (two distinct units separated by a large time interval), petrography (varied Remédios Formation, more uniform Quixaba unit) and geochemistry indicate that the islands represent the activity of a protracted volcanic episode, fueled by intermittent melting of an enriched mantle, not related to asthenospheric plume activity.