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Inadequate global management of fertilizers leads to areas with severe nutrient deficiencies in agricultural lands, linked to insufficient access to fertilizers, thereby limiting food production. On the other hand, there are areas that are over-fertilized, leading to subsequent environmental pollution issues that affect human health. Therefore, a more efficient use of nitrogen (N), phosphorus (P), and potassium (K) fertilizers is necessary for food security while maintaining an environmental balance. The technological study regarding the methods and sources of phosphorus extraction encompasses numerous modern and complex approaches to obtaining and supplying new phosphorus resources. Essential for the daily processes of living organisms and crucial for the growth and development of plants, phosphorus stands as one of the most important chemical elements. As an essential limited resource, the creation of new sources, recycling, and phosphorus recovery are crucial strategies for maintaining environmental balance and reducing dependence on finite phosphorus resources. The different economic and geopolitical characteristics of these three main macronutrient fertilizers need to be taken into account. Phosphorus has the fewest reserves, depending largely on mining efforts, with the majority of reserves concentrated in very few countries. Thus, sources derived from organic or inorganic waste, animal excreta, bone ash, expired food products, wastewater, are exploited through phosphating technologies, thermal treatments, composting, anaerobic biodigestion, adsorption, chemical precipitation, etc. [ABSTRACT FROM AUTHOR]

This study presents a comparative analysis of the efficiency of classic sorting algorithms, including Merge Sort, Quick Sort, Heap Sort, Bubble Sort, Selection Sort, Counting Sort and the enigmatic Bogo Sort. Through a series of rigorous tests on arrays of varying sizes, we measured the time complexities of each algorithm and examined their performance characteristics. Our findings reveal distinctive patterns in the behavior of these algorithms, highlighting their relative strengths and limitations in handling different data structures. By evaluating factors such as time complexity, stability, and adaptability, we provide insights that aid in the informed selection of sorting methodologies for diverse computational challenges. This study contributes to a nuanced understanding of algorithmic efficiency and provides valuable guidance for practical implementation in real-world applications. [ABSTRACT FROM AUTHOR]

In this paper are presented some theoretical and experimental research on the kinematics of planting seedlings of vertical disc type and buckets, the variant of planting directly in the cultivated soil, the kinematics that must ensure the correlation between the working speed of the planting equipment and the speed periphery of the bucket, so that the seedling is planted in an upright position. After a brief presentation of the research carried out worldwide in the field, the kinematic scheme of the planting apparatus and the condition that must be fulfilled by the construction and operation of the apparatus for the correct planting of the seedling are presented. The relations for the projections of the studied point, called the tracer (root of the seedling) and of the afferent angular velocity, are written in a system of xOy coordinates. Using the real values of a studied planting machine, the real and corrected trajectories of the studied tracer point were drawn, using the MatLab program. Following the research, the related conclusions and recommendations for improvement were formulated.

HEMP (Cannabis Sativa - Industrial Hemp) is the industrial plant with the highest use of all these plants in the industry, since nothing is thrown away from this plant. Hemp is the plant of which everything is used, and the products obtained are of a great diversity, from the common rope to the medicinal or cosmetic substances, textiles, automotive or construction materials. It is an unpretentious plant because, apart from the fact that it wants a neutral PH and soils without excess humidity, no maintenance work need to be done and no extra care should be given. The fibre hemp is harvested at the technical maturity when the male plants shed the last pollen grains, and the stalks have a greenish-yellow colour and the leaves fell on the ground. Production management is different for an exclusive fibre production. If we look for raw materials that meet the demands of different areas of the economy with the lowest costs, we must take into account the reactivation of the hemp culture at the level of Romania, because, as we mentioned above, hemp is the plant of which everything is capitalised, and the products obtained are of a great diversity. By applying the technology for processing the stalks in green, the obtained fibre can be used with special results in the strawberry culture at the mulching operation. The paper presents the Equipment for harvesting green hemp stalks ERCV, equipment that performs sequential harvesting of hemp stalks leaving them on the ground. At the same time, factors that influence the process of harvesting hemp stalks are presented: harvesters’ cutting devices, kinematic of the cutting blades, cutting speed, cutting angles of the cutting blades, the forces acting on the blade and the power required to drive the cutting devices.

Hemp is cultivated for its high content in natural, durable, resistant fibres and for its oil-rich seeds. Hemp for seeds is cultivated to fulfil the requests in the technical, cosmetic, food, fodder fields. Hemp has the highest industrialization capacity of all technical plants. Because for a long period of time, the cultivation of hemp in Europe as well as in Romania was in decline, being continuously practiced only in certain European states, it is desired to emphasize how hemp can make an essential contribution to the development of innovative solutions regarding the relaunch of the industrial hemp sector. The paper presents some research results obtained during the realization and experimentation of some technical equipment intended for the mechanization of the works within the hemp cultivation technologies in different systems. The technology of establishing, managing and valorising the hemp culture for fibre or seed can have perspectives starting with the conventional system, the ecological or successive one and at the level of experimental lots. [ABSTRACT FROM AUTHOR]

Harvesting, preparation and conservation of hay is a frequent method for harvesting fodder from grasslands and forage crops, especially from the hill and mountain areas. The greatest losses of nutrients are obtained by traditional drying on the stubble of the hay. These losses are in the case of unfavourable weather even at 50 ... 60%, the drying time increasing to over 6 ... 8 days. This paper presents the results of the experimental researches achieved within a new technology for shortening the time from harvesting the clover to obtaining the hay at storage humidity. A pilot ventilation installation with a monitoring and control system for working processes was used to carry out the research. During the experiments, the parameters of the aeration agent were measured: temperature and humidity, as well as clover mass characteristics: humidity, temperature, drying uniformity.

This paper aims to present the cinematic parameters determination of a drilling equipment design to work in slope degraded terrains, based on field experimental data acquired in normal exploitation condition and also in heavy environmental conditions. This equipment is developed in order conduct forestation and rehabilitation works of degraded lands and to be incorporated on innovative planting technology (degraded soil processing, levelling and terrace surface modelling, planting settlement, etc). This technology answers to the need to implement measures of environmental rehabilitation and enhancement of slope-degraded forestlands, by development several performing equipments that answer to technological needs of this works (land stability, terrace dimensions, type of power source and seedlings planting variety) in order to rise to the performances and to respect the labour safety standards under difficult working conditions. Also, here in presented equipment has a great impact on forestry and pomiculture works, and also on environmental technical works meant to improve soil quality, lowering the surface and depth erosion, rainwater capitalization, lowering the dust pollution and natural calamity risk, and at last to rehabilitate the inland flora.

The current trend manifested globally is to find new solutions using non-conventional energy and renewable energy (solar, wind, flowing waters, biological processes and geothermal heat) in socio-economic activities, as an alternative to classical energies. In this paper we intend to present some research on how to recover the thermal energy released in the biological process of composting biodegradable waste, research which will be finalized by creating and testing a composting container, equipped with recovery plant heat resulting from the aerobic fermentation (composting) of biodegradable waste. [ABSTRACT FROM AUTHOR]

Superintensive growth of fish in a controlled environment involves taking a series of measures to ensure the oxygen necessary to provide optimal living conditions for stocks. Considering the fact that oxygen has a relatively low solubility in water, the photosynthesis in basins does not occur and the rate of incoming water may be low, it is imperative to supplement the water with oxygen. The paper presents theoretical researches on mathematical modelling and numerical simulation of the dispersion of dissolved oxygen injected through porous diffusers in a cylindrical tank, used in fish superintensive growth. The paper aims to identify the optimal placement and sizing aeration system by choosing an adequate number of porous diffusers. In order to carry out the numerical simulation the FlexPDE6 software was used. The simulations have been done in order to judiciously design a recirculating system where oxygen may become one limiting factor in the sense that if falls below optimal value, the fish population is predisposed to asphyxia and death can rapidly occur. [ABSTRACT FROM AUTHOR]

The engineering complex study of the triad "gear-technology-transmission" has permitted to The main objective of this work is to elaborate and investigate the conversion devices for non-conventional energies (wind and hydraulic energy), easy to be stocked and available to a greater number of consumers. The utilisation of aeolian units and hydraulic mini-plants will provide rural consumers with the benefit from partial supply of electrical energy, mechanical energy for the irrigation of their fields, and thermal energy for home heating in cold weather. This will help to reduce the import of fossil fuels for electrical energy production and the emission of polluting gases. [ABSTRACT FROM AUTHOR]