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In economic forests, the productivity of forest stands should be increased as much as possible, because the global demand for timber is growing every year. Planted forest trees can be realized using the advantages of selection, naturally regenerated - faster growth can be achieved by improving the growing conditions and limiting factors that reduce or delay the formation of growth. Data were collected in 6-year-old P.sylvestris forest stands Cladinoso-callunosa and Vacciniosa. The plots were established in an area...

Natural resource management plays a crucial role in regional development as it affects the social, economic and environmental aspects of the region. Effective management of natural resources can contribute to the sustainable development of a region by ensuring the long-term availability of resources and by protecting the environment. An important aspect is the promotion of sustainable practices in the use of natural resources. Sustainable tourism practices are needed that minimize the impact on natural resources w...

Since the prehistoric times, humans have been exploiting the immediate environment for various purposes, from the adaptation of caves for shelter to the subsequent transformation of the landscape for their own needs and this continues to the present day. The bio-inspiration movement in architecture, including bionic, biomorphic, and biomimetic architecture, is linked to the dynamic technological development initiated by the Industrial Revolution and later by the Digital Revolution. Each of these has influenced the...

This research investigates the increasing use of alternative fuels in internal combustion engines, a phenomenon that has experienced significant growth in recent decades due to the heightened interest in reducing atmospheric pollution. Although the pollution level associated with alternative fuels is generally lower compared to fossil fuels, it is essential to emphasize that the pollutant impact of alcohol-based fuels depends on various factors, such as engine technology, mixture composition, fuel quality, and usa...

Mining activities are carried out employing a variety of machineries and equipment; in many cases these can generate relevant health problems for workers. One of the biggest hazards for workers is noise, since prolonged exposure to a noise source could cause damage through long-term exposure. Various researchers pointed out that the damage that can be generated by exposure to noise is of various types with sometimes very serious consequences. Specially drivers of particular vehicles of the mining sector, such as d...

Regardless of its type and size, any organization is faced with risks that can affect the achievement of its objectives in terms of activities, strategic initiatives, operations, processes and projects, with different consequences on strategic, operational, financial results and image and reputation. All activities of an organization involve risks, and risk management is the process of substantiating the decision, by taking into account the effects of uncertainty on the materialization of objectives and determinin...

The Constitution of Georgia provides the main principles of protection of employees and employers at job places, concerning healthy and safety conditions. The paper reviews the new Laws of Georgia pertinent to labor safety, elaborated and approved during the last years. These Laws regulate social-economical, technical, hygienic and other conditions of work of employees at job places. These are Laws, destination of which to secure the workers health and safety in the present, future and must not have a negative inf...

In this moment the populations of Scolopendra cingulata from Austria, Hungary and the new discovered populations from Romania represents the northern limits of S. cingulata in Europe. These three northern small populations of S. cingulata are very important in understanding the evolutionary history of this iconic species for Europe.

Urban meteorological parameters and traffic emissions are characterized by microterritorial variability. Online weather and traffic information is the basis for creating online services to provide users with information about the toxicological risk, noise effects and thermal stress risk. The purpose of this work is to assess the possibilities of online environmental modeling. The methodology includes special field studies to select model parameters, developing models for online calculations of noise levels, concen...

Heat pumps are important due to their efficiency and a target of climate neutrality. They also reduce the emissions of carbon dioxide. This article deals with the smart mini hybrid heat pump, which is planned to use for heat gain in summer, energy accumulation in the ground storage, and further consumption in winter. This heat pump can get heat from the surroundings or solar collectors. Heat pump water-water has been used in this article. Its input and output parameters were measured, a coefficient of performance ...

This paper explores the operational characteristics of a DC islanded microgrid engineered to produce green hydrogen, utilizing power sourced from a solar array complemented by an energy storage system. The model simulates a one-week evaluation period, incorporating comprehensive analyses of electrical, thermal liquid, and thermal gas domains. By examining the interactions between the solar array, energy storage, and electrolyzer, the study provides a detailed assessment of system performance under varying conditio...

Sustainable tourism at the regional level is an approach to tourism development that aims to maximize economic, social, and cultural benefits for local communities while protecting and conserving the surrounding environment and cultural heritage of the region. This concept emphasizes responsible resource management, reducing environmental impact, and promoting social and economic inclusion. By adopting principles of sustainable tourism, the tourism industry can contribute to the conservation and protection of natu...

Modern agriculture, or precision agriculture, is a method that enables better, more efficient and smarter farming, ensuring sustainable development. Precision agriculture can combine data obtained from GPS systems with data from aerial photographs to precisely determine soil needs based on this data. Combining this with precise weather forecasts and location determination systems provides a powerful tool for more efficient agriculture. New technologies have already created a niche in agriculture. By combining deta...

The scale of annual reproduction of cellulose-containing biomass in nature allows us to draw an unambiguous conclusion that cellulose is the only source of raw materials for the chemical and fuel industries, representing a real alternative to fossil resources and, first of all, oil. Cellulose is the main component of plant biomass. According to some estimates, almost half of the organic carbon in the biosphere is contained in cellulose. Hydrolytic hydrogenation is a special case of carbohydrate hydrogenation. With...

The study of a gravimetric network is closely connected with determining the value of the drift on the gravimeter scale (zero-point drift; drift). The realization of a great number of over-measured quantities makes preliminary processing of gravity measurements a hard, slow, and delicate process. The main purpose of this research is to investigate a method that would simplify the overall technology of gravimetric measurement and post-processing of the results obtained. A modification of the commonly adopted adjust...

The olive oil sector is one of the most widespread agricultural and agro-industrial activities in the Mediterranean region, and it also produces a significant amount of waste biomass. This research aimed to find energy valorisation for the olive oil by-products through biogas/biomethane production from olive pomace (OP) and olive mill wastewater (OW). To this end, these biomasses underwent preliminary treatments: the OP was processed using an ionic liquid (IL) consisting of triethylamine and sulfuric acid [Et3N][H...

This paper presents an in-depth analysis of a residential solar thermal system designed for domestic hot water (DHW) production in a single-family dwelling located in Mangalia, Romania. Positioned at a latitude of 43.894- and a longitude of 28.422-, Mangalia benefits from an annual global irradiation of 1403 kWh/m?, providing favorable conditions for solar energy utilization. The study evaluates the system's performance over the course of a year, focusing on energy consumption, solar fraction, and environmental be...

In light of the pressing need to achieve climate neutrality in the energy sector, the European Union seeks to identify strategies that will enhance and diversify its green energy supplies. As a renewable energy source, green hydrogen promises to offer a viable alternative to fossil fuels where green electricity may be insufficient or inaccessible. This is why the production and supply of this innovative energy carrier is becoming a significant focus in EU politics and research. This article examines and compares p...

Automation of complex technological and laboratory systems requires the creation of specialized mixed-critical computing systems. They must control the technological process at several levels (control subsystem) and maintain the user interface with technological data management (information subsystem). So, they execute tasks with significantly different criticality. Also, it is assumed that the development of physical components, the implementation and configuration of the control subsystem at different stages of ...

Ukraine actively participated in the implementation of the provisions of the European Green Deal (EGD), seeking to build a "green" economy and a prosperous society. The purpose of this study is to determine the forms and directions of activities of public associations in the implementation of the provisions of the EGD in Ukraine. Influential public organizations involved in the implementation of the European Green Deal are the Center for Environmental Initiatives "Ekodiya" (Kyiv), "Ekoclub" (Rivne), "Ecology. Righ...

Hydrogen-based energy production involves the use of fuel cells or the direct combustion of hydrogen (a particular case being hydrogen combustion in internal combustion engines). Direct hydrogen combustion is still in the testing phase, with challenges arising from its energetic properties, which continue to be a difficult factor. For instance, hydrogen has a low calorific value (about three times lower than methane) in its gaseous phase, which is the phase where combustion occurs, a very high combustion speed (ab...

Natural gas hydrate reservoirs often consist of a mixture of various gaseous species: small-chain hydrocarbons, as methane, ethane, propane and butane, and other species, as carbon dioxide, nitrogen, oxygen, hydrogen sulfide and others. Every species shows different forming conditions. Moreover, those conditions may change as a function of the mixture composition and the properties of the surrounding environment. The present study deals the production of hydrates with small-chain hydrocarbons, within a silica-base...

Climate change has an increasingly significant impact on the lives of people around the world. In this context, of particular interest is the study of the philosophical aspect of climate change in the Sakha Republic (Yakutia). The study is based on a philosophical analysis of climate change, as well as a generalization of the opinions on environmental issues. The main method is a logical-analytical approach to revealing the philosophical context of climate change in the context of Yakutia. A philosophical view of ...

Biochar can be used as an alternative and efficient adsorbent for organic and inorganic pollutants. Therefore, based on previous study in which, a biochar loaded with mixed metal oxides of iron, tin or titanium catalysts results as a by-product of levulinic esters synthesis from biomass carbohydrates, this paper aim was to test this residue as biochar for the retention of phosphate from water samples. The obtained adsorbents based on Fe2O3-SnO2 and Fe2O3-La2O3-TiO2 were characterized by FT-IR and TGA analyses. The...

In isolated areas without access to the grid where it is necessary to operate certain equipment, such as the operation of a valve in a mining area or some gates on a irrigation canals, an installation with fotovoltaic supply can be used. Considering the intermittent operation regime of the driven equipment, a solar-powered drive installation can be designed, and by storing the energy in a battery, operation can be ensured during the night as well. Thus, the PV power system must be sized (PV peak power, battery and...

Hydrogen, known for its high flammability and potential explosive characteristics, presents significant challenges in safety engineering, particularly in enclosed spaces where explosions can lead to catastrophic consequences. This paper presents the results of physical experiments conducted to investigate the linear propagation of hydrogen explosions within confined environments. The experiments were designed to simulate real-world scenarios and assess the factors influencing the extent and characteristics of expl...

The aim of the project concerns the production, characterization and impact on consumers of biscuits with wholemeal flour and grated carrots. The innovative character results from the use of wholemeal flour, which, unlike white flour, retains the bran and wheat germ, making it richer in fiber, vitamins and minerals. This contributes to a lower glycemic index and a superior nutritional profile. Carrots provide moisture and natural sweetness and are also an important source of beta-carotene, fiber and other vitamins...

Phytoremediation technology is environmentally friendly and inexpensive to clean soils of harmful toxins. The study aims to introduce phytoremediation of arsenic in the Racha-Lechkhumi and Kvemo Svaneti regions to restore soil fertility. For this study, three plants, Amaranthus gangeticus, Chenopodium album and Helianthus annuus, were selected for the accumulation and translocation of Arsenic from the contaminated soil. The seeds of selected plants were treated with the bioactivator Biorag to increase the plant's ...

Orphaned or abandoned sulphide tailing disposal sites pose significant environmental hazards, including eolian dispersion, water erosion, acid mine drainage, and heavy metal mobility. Phytostabilization, an eco-friendly strategy, entails the use of alkaline amendments alongside non-native plant species capable of thriving in environments with high concentrations of heavy metals. A greenhouse experiment was conducted to assess the effect of a commercial cement which contained 46.3% sand, applied alone or combined w...

This research compares the water quality in four river bodies passing through different cities in Bulgaria. An eco-chemical approach was applied including physicochemical and analytical measurements, as well as calculation of different pollution indices and the distribution of the element species as an indicator of their bioavailability. The results from analytical measurements and calculated pollution indices show that all the studied water bodies were polluted regarding P-PO43?, N-NH4+, Mn, and Pb. The highest v...

Ticks (Ixodidae and Argasidae) pose significant health risks as vectors for infectious diseases, with their prevalence expanding across Europe and North America. Ticks employ sophisticated sensory mechanisms, notably utilizing Haller's organs, to locate and sense their hosts. These sensory structures detect various cues, including chemosensation, changes in atmospheric CO2 concentration, and radiant heat emitted by potential hosts. Once a host is detected, landing is facilitated by electrostatic attraction, accele...

In this paper, there are presented the characteristics of reinforced concrete structures that are subjected to a corrosive environment. These structures allow for the appearance and opening of short-term and long-term cracks within certain limits during operation, as well as the variation in the moisture of the concrete depending on the ambient humidity. The basic nature of the concrete allows it to react with acids, while its increased porosity enables the absorption of liquids and gases, including aggressive one...

Biomass is the first form of energy used by man at the same time with the discovery of fire, means all the products of animal and vegetable origin used in present in the production of energy. Actually, the biomass approximately half (44-65 %) of the total renewable energy sources used in the EU, and occupies a third place as a primary energy source in the world, after coal and oil. At the same time represents a sustainable alternative to reduce carbon emissions. The experimental territory is located in the middle ...

Today, it is possible to work with a wide range of freely available data, often on a daily basis. These data can be used to create an early warning system for estimating the approximate hazard. It can also be used to develop models of long-term catchment behaviour. Most applications are generally carried out on catchments larger than 200 km2. For this reason, areas between 20 and 350 km2 were selected to test the hypothesis using models based on machine learning methods. How good results can be achieved when using...

The paper aims to identify the availability of water sources for water supply of local irrigation systems. Where the location of the land involved in the works is located at a large distance from the surface water sources, the only viable option is the use of water from the shallow water table. The identification, delimitation and characterization of underground water bodies is done in accordance with the specific methodology developed within the National Institute of Hydrology And Water Management, based on hydro...

In the evaluation activity of technical equipment intended to be used in potentially explosive atmospheres, by national and international legislation, non-compliant aspects were often reported regarding the choice, installation and maintenance of this explosion-proof equipment. The following main aspects were pointed out: the equipment that was initially chosen and installed appropriately for the specific application but later, over time, improperly maintained; respectively, the situation in which they were inappr...

Geophysical studies on the lunar surface have, in the past, used various methods that contribute not only towards the knowledge of the lunar subsurface but also contribute towards the design of future lunar missions, namely those that will, in the near future, take humans to the Moon-s surface. This work analyzes a specific set of ground penetrating radar (GPR) data, collected during the Chang-E-4 mission of the Chinese Space Agency, using theYutu-2 rover within the von Karman crater, on the far-side of the Moon. ...

The research objective was to develop a methodology for determining the total suspended solids concentration in wastewater based on the color indexes analysis. Determining the structure and properties of natural objects by processing its digital images has become widespread in soil science, since the soil colour is determined by its chemical and mineralogical composition. The material presented in the research can be considered as the initial steps in the development of soil science methods as applied to research ...

Effectively preventing pipe sticking in oil and gas wells is a key aspect of safety and productivity in the oil and gas industry. This paper presents a new torque and drag model developed using machine learning techniques to improve accuracy and predictive capabilities. The model is based on a comprehensive analysis of many factors, including geological characteristics of the well, drilling parameters, fluid parameters, hydraulic conditions, and production equipment parameters. This research explores the applicati...

The groundwaters draining in the continental shelf area can be an unconventional resource of fresh water for drinking, irrigation, and industrial purposes in water-scarce coastal areas. Recently, possible offshore sources of such groundwater in the coastal zone have been subject of increased investigation and description. The aim of the present research is to identify similar, available for use, potential sources of Offshore Frehsened Groundwater (OFG) in the area of the shelf of the Northern part of the Bulgarian...

The results of our study revealed regional peculiarities, which showed an excess of the share of PM10 compared to PM2.5 in the rank distribution and high concentration of soot in the level of impact on public health. It was found that the distribution in terms of contribution to the total risk value (HQ) of the main pollutants is highest in all three zones: carbon (soot), nitrogen dioxide (NO2), suspended solids (PM), where the main share is suspended particles up to 10 microns (PM10). Among the studied zones, zon...

In the present study probabilistic earthquake, scenarios for the city of Varna the third-largest earthquake-prone city in Bulgaria are presented. The probabilistic hazard for a city is obtained by integrating the effects of ground motion from earthquakes of different size occurring at different locations within different seismic source regions and with different frequencies of occurrence. The ground motion maps for the city of Varna are generated combining via GIS, source geometry, earthquake occurrence model, max...

The most attractive option to recover methane trapped within natural gas hydrate reservoirs, consists of the so-called -replacement process-, mainly based on the contemporary injection of carbon dioxide during the mining process. If appropriately carried out, this process allows to improve the amount of methane recovered, preserve the crystalline hydrate cages and permanently store enough carbon dioxide to make this source definitively carbon neutral. For that reason, this process is widely studied worldwide. Howe...

Bioeconomy industries play an important role in contributing to national economies and a transition to climate-friendly farming practices. This is evidenced by various policies implemented, including the United Nations Sustainable Development Goals, the European Union (EU) Bioeconomy Strategy and the European Green Deal. The increasing productivity and new technologies can have negative environmental impacts, affecting the economic framework associated with ecosystem services. To address these challenges, coordina...

Technological advance has assured humanity-s desire to increase its quality of life, anyway humanity is currently confronted with several global challenges, their complexity bases on their interconnectedness, and on fast changes in technological field. Present space activities are directed to explore the potential of diverse celestial bodies to have hosted life. In this context the Moon Village Association, MVA has as its main objective creating a global informal forum for governments, industry, academia for debat...

Geographic information systems (GIS) are based on the approach of displaying data from individual layers, where a manageable number of geospatial objects are displayed within a single layer. The entire content of a hydrogeological model (HM) can only be partially included within this framework. HM input data and modeling results as layer surface maps are a way to easily, clearly, and simply publish the model content and simulation experiment results. However, this approach is not sufficient for regional HMs. Regio...

Potential environmental impacts of growing maize as monoculture lead to efforts focused on finding other potentially suitable crops or their combinations that could replace the pure maize cultures. The most frequent and most effective combination is a mixed crop of maize and legumes. The presented paper deals with the issue of the quality of post-harvest residues when growing maize in the system of mixed cropping. In the field experiment, yield and quality of post-harvest residues were studied during the growing s...

Receiver function analysis is a critical tool in seismology, used to study the deep structure of the crust and upper mantle. Information about the deep structure of the crust and seismicity is important initial data for developing a source model and seismic hazard assessment. The presence of sharp discontinuities beneath the monitoring station induces the generation of converted body waves, which propagate at slower velocities than those of the primary P-wave. Receiver function analysis utilizes the lag between th...

Snow cover is an indicator of the fluctuating climate, resulting from the change in the regime of winter precipitations and air temperatures. Our previous studies have revealed significant decreasing of the seasonal snow cover maxima and the precipitation amounts in the highest mountainous regions of Bulgaria, which is however not so strong at lower altitudes. Current research summarizes our last findings about one other characteristic of the snow cover - its duration. This is presented as annual number of days wi...

The depletion of primary raw materials and the demand in High Tech has played a big role in finding new ways of getting raw materials including recycling. Germanium being a semi-conductor currently in high demand is being sourced from secondary materials. The purpose of this project was to recover Germanium from copper slag in the presence of pure silicon using the carbothermic reduction process. The experiment was designed using Minitab software with Taguchi as the tool for statistical analysis and to design the ...