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This research investigates the influence of printing parameters and different materials on the geometrical and dimensional deviations of Fused Deposition Modelling (FDM) additive manufacturing. Using the Taguchi method, experiments with four factors are designed: print layer height, printing material, printing speed, and nozzle size, employing an L9 orthogonal array. Deviations in flatness, perpendicularity, parallelism, cylindricity, spherical form, and surface roughness of 3D-printed parts are evaluated. The results reveal that print speed and nozzle size significantly affect flatness and surface roughness, while layer height and material influence perpendicularity and parallelism deviations. Notably, nozzle size critically impacts cylindricity and spherical form deviations. Our study demonstrates that lower printing speed, smaller nozzle diameter, and reduced layer height are not universally optimal; instead, parameter adjustments based on specific geometrical requirements and part orientation are necessary. These findings are essential for improving the accuracy and quality of FDM-printed parts, supporting their broader application in precision manufacturing industries.

Floods are natural disasters that cause damage, loss of life, and economic problems throughout the world. Part of these losses can be minimized with the help of different methodologies and tools used to prepare simulations, analyses, and data monitoring to predict such phenomena in time. The metropolitan area of Cluj-Napoca, Romania, is the study area of this paper and it is located in Floresti, the largest rural settlement in Romania. In this area, changes in urbanization, land use, and the expansion of urban areas in a chaotic mode represent a problem. This study focuses on an area prone to flooding due to its proximity to the Somes River. Previous events of this type have caused economic losses that must be considered. This approach combines photogrammetric methods for obtaining data from the field with topographical methods for establishing control points and GIS methods for data processing, modeling, and simulation to obtain the necessary data for flood prevention and intervention.

Brownfields are a real problem which affects the urban appearance of cities and the quality of life of their inhabitants. In Romania, industrial areas were mainly concentrated on the outskirts of large cities, in the immediate vicinity of residential areas. With the closing of factories and the additional population of the big cities, there was a need for expansion of residential areas with a social-economic function. This paper proposes a case study from the classical surveying measurement equipment (GNSS—Global Navigation Satellite System and TS—Total Station) for land use planning of brownfield regeneration projects. The chosen area is in the northwest part of Romania, in Cluj-Napoca, where a former brick factory was closed, leaving behind unaesthetic and unused land. In this paper, it is suggested that a better understanding of the way in which UAV—Unmanned Aerial Vehicle—aerial photogrammetry can contribute to providing information for the design and development of this area. In addition, this study confirms the advantages of effective and practical use of the obtained geospatial information for the design of a residential complex in the studied area, a complex proposed as a sustainable alternative to the former industrial area. Observation and analysis of the differences between the two topo-geodetic works were carried out with the help of UAV technology, such as GNSS—Global Navigation Satellite System and TS—Total Station technology, respectively, to create a topographic plan, level curves, and 3D models made of the building in the study area.

This research investigates the influence of printing parameters and different materials on the geometrical and dimensional deviations of Fused Deposition Modelling (FDM) additive manufacturing. Using the Taguchi method, experiments with four factors are designed: print layer height, printing material, printing speed, and nozzle size, employing an L9 orthogonal array. Deviations in flatness, perpendicularity, parallelism, cylindricity, spherical form, and surface roughness of 3D-printed parts are evaluated. The results reveal that print speed and nozzle size significantly affect flatness and surface roughness, while layer height and material influence perpendicularity and parallelism deviations. Notably, nozzle size critically impacts cylindricity and spherical form deviations. Our study demonstrates that lower printing speed, smaller nozzle diameter, and reduced layer height are not universally optimal; instead, parameter adjustments based on specific geometrical requirements and part orientation are necessary. These findings are essential for improving the accuracy and quality of FDM-printed parts, supporting their broader application in precision manufacturing industries. [ABSTRACT FROM AUTHOR]

Sharing economy represent a complex concept that is intensively debated in the last decade. Proposes an economic model based on collaborative consumption and four different layers: circulation of goods, increased utilization of durable assets, exchange of services, and sharing of productive assets. The present article wants to investigate how Romanian consumers relate to a carpooling application - BlaBlaCar. Consumer perceptions are measured in a quantitative research as an online field survey addressed to users of the BlaBlaCar platform who have completed at least 3 trips in the past 2 months. The results of the research are discussed and analyzed not only from the point of view of factors that are determining the consumption decision for this kind of services but from the point of view of future implications regarding consumption social models and the development of sharing economy and collaborative consumption within the context of Romanian economy. The findings are showing that a large part of educated, young and middle age consumers from the urban area with medium to large incomes are embracing on a wide scale a new model of consumption, which is characterized by the sharing of resources, intense social engagement and a new type of free transactions.

Agricultural land is one of the main resources for the development of rural communities and the peripheries of urban centres. An area of 936 km2, belonging to Intercommunity Association for Development Alba-Iulia, Transylvania region, Romania, was analysed in order to identify suitable land for agricultural use. This approach represents the stage preceding the identification of crops favourability for agricultural land, thus reducing the time and resources needed for the proper land evaluation mark. The extension of suitable surfaces for agricultural crops was realized using a GIS model based on spatial analysis, taking into account morphometric parameters (slope, altitude, slope orientation, the density of fragmentation) and the risk factors (probability of landslides, flooding, temperature and rainfall). The outcome of the case study was an agricultural land suitability map of the investigated area, which provides valuable information regarding areas suitable for crops. By applying this model, a better management of agricultural lands can be assured, representing an alternative to the classic method of evaluation marks. The proposed model was validated by comparing the results with the grades of crop suitability, method achieved through the land evaluation mark.

The paper presents an investigation on the conditions for implementing a methanation membrane decarbonator coupled to an energy installation that generates flue gases. The retention of the carbon dioxide content in the flue gases and its conversion to methane is envisaged. For start, low thermal power installations, employing natural gas as main fuel supply, are considered. Internal combustion engines (also working with natural gas fuel) are taken into account for the testing of the carbon dioxide retention process. For this, a classification of the flue gas composition by fuel categories is initially carried out. The decarbonation efficiency is defined and clarifications are made withal regarding the connection between the decarbonation installation and the energy plant. The first practical achievements are also presented, resulting from a decarbonator with a volume of 940 cm3 (having the inner diameter of 12 cm and a height of 50 cm). The results prove that the proposed solution has great potential for practical applications, further research being however necessary. In terms of operating costs (including hydrogen consumption), it is remarked that they can be reduced by exploiting the methane production and eliminating the carbon tax, extending the integration perspective form economic point of view.

Transition type fittings are components often used in facilities where fluids are transported that allow the passage from a high density polyethylene (HDPE) pipe to a steel pipe. In the presented studies, four types of transition fittings were analyzed in the first stage. The four types of transition fittings are distinguished by the shape of their welded steel construction. The performed analyses took into account testing the behavior upon exposure to fatigue, measuring the HDPE hardness and applying the finite element method (FEM). As a result of these studies it was demonstrated that the form of the welded steel construction has a very great influence on the operating behavior of the transition fitting. Thus, a new transition fitting with a welded steel construction was designed. In this new type of transition fitting, an approximately 50% increase in resistance to fatigue stress, an approximately 90% reduction in stress in the part material and a reduction in the hardness of the material in HDPE pipes was obtained. The studies allow not only an improvement of the characteristics for these types of parts, but also the optimization of other types of steel-plastic joints.

The purpose of this paper is to explain the need for collaboration and to investigate the obstacles in collaborative engineering. The first part is about defining the term collaboration. The second part focuses on the information outside the domain of engineering which could prove to be valuable to this field as well. The final part shows different obstacles in collaborative engineering.

In Romania all areas used for extracting salt were affected due to mining activity, operating methods used and also due to dissolution of the salt back flanks through contact with water. To prevent subsidence events in salt deposits, there must be imposed a series of measures and restrictions in these areas by topographic monitoring, hydrogeological monitoring, construction banning etc.

The experimental research has highlighted the variety of possibilities of combustion of animal fat from bovine and swine mixed with liquid hydrocarbons. Previous research has established that the upper limit for an efficient combustion was 30 %. For a perfect mixing, the lower temperature limit was set to 40 °C. In the fuel laboratory, at the department TMETF was determined the viscosity of the mixtures for different proportions. The values obtained for various concentrations and preheating temperatures were close to the values for liquid hydrocarbons. The experimental researches have studied the combustion of the mixture using a mechanically spraying burner with constant pressure between 14 and 18 bar. The aspiration of the mixture is done from a specially designed tank; this tank is equipped with an electric heater, in order to maintain the mixture at a constant temperature between 40 °C to 50 °C. After that, the burner heats again the mixture with an integrated heating device up to 75 °C. The burner is also equipped with an air blower, pump and a calibrated nozzle. The combustion resulted from the experimental boiler with a power rated to 55 kW were monitored with a thermal vision camera and an exhaust gas analyser. This research has demonstrated the viability of using this type of mixtures in energetic burning equipment designed for liquid hydrocarbons.

In Romania, the hydropower is the main form of renewable source with an important share in energy mix. Despite their valuable advantages on supplying energy and balancing the energy system, public acceptance, environmental, social and economic impact has become a common challenge in development of hydropower projects. Increasing of water consumption and raising awareness regarding available water resources leads to an integrated management approach of them. In this paper the water footprint is estimated for one of the largest Romanian hydropower project, namely Hydropower Plant Vidraru. The water footprint from hydroelectricity is evaluated considering electricity production of the hydropower plant, water footprint of dam construction and three different approaches to quantify water footprint of the reservoir: gross water consumption, net water consumption and water balance. Also, water footprint is assessed based on economic value of the reservoir using allocation coefficients for various purposes of the reservoir. It is estimated that economic benefit of the reservoir is 81.92·106 €/y, with hydroelectricity major contributor.

The evolution of relationship marketing has been one of the most talked about, partly because it not only proposed a radical change at the very beginning of the marketing action and philosophy, but also because of its complexity. Among many different issues regarding the relationship marketing, the one referring to the strategic planning process has been very little dealt with among the marketing specialists. The present article discusses this sensitive matter and represents a short insight into this complex dilemma: is planning possible or not when talking about commitment, trust, harmony, empathy with the consumer on a regular basis, during a lifetime relationship?

Apple scab caused by Venturia inaequalis, is an important disease, spread worldwide, having a major negative impact in apple production. In this study, there were analyzed four apple cultivars (Liberty, Florina, Starkrimson, Golden Spur), used as genitors in a diallel cross, and their seedlings. In the field, plants selection was done after presence or absence of the scab on leaves, and afterwards, phenotipically selection was completed by marker assisted selection. The molecular analysis conducted with the markers AL-07, AM-19 and U1400, detects the presence of the Vf gene, introgressed from Malus floribunda 821, which confers resistance to the pathogen, in the parental cultivars Liberty and Florina, and in all the F1 hybrids belonging these two genitors. Starkrimson and Golden Spur were susceptible scab parents with recessive homozygous genotype (vfvf), while Liberty and Florina were identified as heterozygous scab resistant parents with genotype (Vfvf). From the 60 apple seedlings analyzed, grouped in six combinations after their genitors (in each combinations were selected ten hybrids, among them five resistant and five susceptible to apple scab attack) 28 were resistant and heterozygous for Vf gene (Vfvf) and 32 were susceptible to scab with recessive homozygous genotypes (vfvf), being obtained almost Mendelian ratio for response to the pathogen, 50% resistant: 50% susceptible. Seedlings belonging to Starkrimson x Golden Spur were only recessive homozygous genotype (vfvf), and in combination resistant x resistant (Liberty x Florina) were identified susceptible and resistant offspring, but at last, only with heterozygous for Vf gene (Vfvf) and no one with dominant homozygous genotypes (VfVf).

The publication of a scientific paper stirs up both a lot of interest and rivalry. Should the topic be of a great concern, then the desire to purchase and study the paper appears. This is what the Societatea europeană a cunoaşterii volume undoubtedly brings up, after being published by the prestigious Romanian Academy Publishing House...

To sum up, Fizeș Plain is a territorial unit well highlighted in the Transylvanian Plain. This region is delimited from the other units which compound the Transylvanian Plain, especially through its physical and geographical features. For the purpose of this research, soil samples were taken for each main pedogenesis horizon. Also, physico-chemical analysis was performed according to the methodology that currently exists in romanian pedology and agrochemistry laboratories. Some of the analysis methods include Pipette method of interpreting the results after ICPA-Kacinski, Cylinder method (with known volume) and others, as seen in table 1. As a result, regarding the physical-geographical conditions, it has been established that this territory is located according to the soil studies in category III C of complexity. Furthermore, this sector can be considered a curved area of the structure in domes and brahianticlinales, where elevations exceed 400-550 m only on the interfluvial plateaus. Its relief is moderately fragmented, being defined by interfluves that are radially oriented towards South, South-West, as well as towards South-East, as given by the hydrographic network. In conclusion, the soil in the Fizeș Plain area is diversified both in space and tyopology due to the complex factors that have contributed to the solidification process.

To sum up, talking about ravines implies first of all a stop upon what water erosion means. That’s why it’s important to point out that water erosion is a comlex phenomena that affects the soil cover from the Transylvanian Plain and is triggered by a number of changes that act both in time and in space. Water erosion, as well as surface drain and water infiltration on the soil’s profile is mainly due to the intensity of the rain, the nature of soils and the vegetation coverage. This study’s aim is to assess the types of existing ravines in Northern and North-Western Transylvanian Plain, by taking into consideration the water erosion’s effects. For the purpose of this research the ravine’s morphology, the soil’s texture and structure, as well as the hydraulic permeability and conductivity were analyzed. In conclusion, the evaluation of the current status of ravines from Unguraș Hills and Fizeș Plain have provided a series of observations regarding the typology of the existent ravines in these two regions. Field results revealed a strong correlation of the ravines’ formation processes with their control factors, especially with the use of the land, the slopes’ inclination degree, climate conditions and geological structure.

In this paper, we propose an electrical design (implemented on a PCB board) and an accompanying software design for controlling the automatic gear change. The designs complement the mechanical solutions developed in Part 1. The paper also analyses the issues encountered during the intermediate steps of the development of the electronic module, which is expected to be small and adaptable enough to be installed on a motorcycle without changing its ergonomics. The control software runs on the Arduino Nano board and is built as a state machine with one idle state, five active states that cover different stages of the gear change and one error state for preventing malfunctions in case of an unexpected event. The sketch uses 5,760 bytes (or 18%) of program storage space and 706 bytes (or 34%) of the dynamic memory.