THE EVOLUTION OF THE CAPITAL MARKET IN ROMANIA IN THE CONTEXT OF THE COVID-19 PANDEMIC

The purpose of this study is to emphasize the main aspects regarding the evolution of the capital market in Romania in the context of the COVID-19 pandemic. This study tries to present the main aspects which marked the evolution of the national capital market in the last period. The domestic capital market went through a delicate period during the beginning of 2020, since in times of crisis the stock markets react emotionally and thus, are recorded relatively important fluctuations. Although the COVID-19 pandemic created a lot of uncertainty in the capital market, the end of 2020 brought back optimism among investors. In 2021, the d domestic capital market recovered all the decreases registered in 2020 and ended this year with very good results

STUDY REGARDING THE INFLUENCE OF CORROSIVE AGENTS ON THE SURFACE OF METALLIC MATERIAL LIKE STEEL

Corrosion is a process that involves the action of different agents on material surfaces. Corrosive agents in corrosion field can be ambient, saline and microbiological mediums. These agents can influence the mechanical properties of metallic material like steel. The aim of this research is to present the mechanic properties of sheet steel submitted at the action of corrosive agents. The metallic samples were analyzed in order to determinate the resistance at corrosion by stress-strain curves, deformation limit curves and (Atomic Force microscopy) AFM images. Relative results are obtained in the case of saline medium corrosion, meaning that the saline medium corrosion influences the metallic sample, in proportion to the degree of salinity. Also, the AFM images and topographies of metallic surface confirm this conclusion

THE OPPORTUNITY OF USING CLOUD-BASED COMPUTING IN NUMERICAL SIMULATIONS ON STRUCTURAL ANALYSIS - CASE STUDY

To make the most accurate behavioral assessments of mechanical parts, engineers rely heavily on numerous software solutions. These software solutions are able to solve more or less complex problems with a fairly high degree of accuracy and similarity to physical experiments. The common feature of these software solutions is that they need generous resources from the computer on which they are installed. Can't it be done differently? One possible answer may be the use of cloud-based solutions. The main purpose of this paper is to make a comparison and find the limitations of such a solution relative to the established ones in the field of finite element analysis. Therefore, this paper is a case study in which an industrial component – beam bracket – is subjected to a structural analysis on three different software solutions. The reference systems are: ANSYS, a solution dedicated to finite element analysis and SolidWorks Simulation, a solution often used in industry for the assessment of mechanical structures. The cloud-based solution is SimScale, a software product based on open-source codes: Code_Aster and CalculiX

THE OPPORTUNITY OF USING CLOUD-BASED COMPUTING IN NUMERICAL SIMULATIONS ON STRUCTURAL ANALYSIS - CASE STUDY

To make the most accurate behavioral assessments of mechanical parts, engineers rely heavily on numerous software solutions. These software solutions are able to solve more or less complex problems with a fairly high degree of accuracy and similarity to physical experiments. The common feature of these software solutions is that they need generous resources from the computer on which they are installed. Can't it be done differently? One possible answer may be the use of cloud-based solutions. The main purpose of this paper is to make a comparison and find the limitations of such a solution relative to the established ones in the field of finite element analysis. Therefore, this paper is a case study in which an industrial component – beam bracket – is subjected to a structural analysis on three different software solutions. The reference systems are: ANSYS, a solution dedicated to finite element analysis and SolidWorks Simulation, a solution often used in industry for the assessment of mechanical structures. The cloud-based solution is SimScale, a software product based on open-source codes: Code_Aster and CalculiX

STRETCH FORMING USING HEATED DIE

The stretch forming process implies stretching and drawing into shape a sheet of material onto a die. This method is used, among other sectors, in the construction of aeroplane fuselage, as significant, complex parts can be obtained in one piece. In essence, stretch forming implies working with materials that have medium to high spring back effects, such as aluminium or magnesium alloys. Different approaches are used in manufacturing due to this phenomenon, ranging from incremental processes to multipoint dies. Another critical aspect of this process is to know how the material behaves under severe plastic deformation, as different alloys require different approaches that vary from step by step forming to in-process chemical treatments to manual pounding the metal sheet. However, all these alloys have in common that, when heated, their machinability properties improve. In this experimental study, a heated die approach was taken into consideration. 6x60 mm 100W heating elements along with temperature sensors were fitted into the die. The USB/OC326009 metal sheet is in direct contact with the die, thus assuring the heat transfer, as the temperatures reach 200 °C. The die temperature is software controlled so that maximum temperature and thermal inertia could be controlled with ease. The data indicate that this method offers significantly improved results compared to a normal room-temperature process

ISO 9001 International Standard, a Tool to Enhance Data Quality in Durable Socio-Technical Systems

International audienceThe quality of data is recognized to be a key issue for the assets management in enterprises as data is the foundation of any decision making process. Recent research work has established that the quality of data is highly dependent on the knowledge one has on the socio-technical system being considered. Three modes of knowledge have been identified: knowing what, knowing how and knowing why. In this paper we focus on how to manage these modes of knowledge in durable socio-technical systems to enhance the data quality face to technological progress and employees turnover. We believe that an organization based on ISO 9001 international standard can provide a valuable framework to provide the data quality needed to an efficient decision making process. This framework has been applied to design the data quality management system within a high education socio-technical system. The most important benefits that have been noticed are: 1) a shared vision on the external clients of the system with a positive impact on the definition of the strategy and the objectives of the system and 2) a deep understanding of the data client-supplier relationship inside the socio-technical system. A direct consequence of these achievements was the increasing knowledge on “know-what” data to collect, “know-why” to collect that data and “know-how” to collect it

Adsorption of lead(II) ions from aqueous solutions onto Cr-pillared clays.

International audienceThe present paper presents the synthesis and characterization of porous nanomaterials, the Cr(III) being the metal oxide used as pillar intercalated between the layers of montmorillonite. The raw material used to obtain the pillared clays was a Romanian natural calcium bentonite, which was provided by S.C.Bentonita S.A. The main parameters were varied (metal ion for ion exchange process, aging temperature and duration for pillaring agent preparation, meta/clay ratio) in the aim of obtaining nanomaterials with high adsorption capacity of lead ions from waters. The modified clays were characterized by nitrogen adsorption technique, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The determination of Pb(II) ions concentration was realized by atomic absorption spectrophotometry.The obtained results showed that the basal distance and specific surface area varied with the parameters of materials preparation. The nanomaterial with the best textural, structural and morphological properties was chosen in the aim of its using in Pb(II) adsorption from aqueous solution.The Langmuir and Freundlich models were used to fit the experimental data and these showed good correlations

Adaptive Stretch-Forming Process: A Computer Vision and Statistical Analysis Approach

An industrial process is defined through its quality of parts and their production costs. Labour-intensive operations must be applied to produce high-quality components with inexpensive resources. Recent development in dedicated software allows the industrial sector to rely on more and more autonomous solutions to obtain an optimum ratio between part quality and cost. The stretch forming process is an operation that has a high degree of difficulty, due to the process parameters and the spring-back effect of materials. Our approach to solving several of the shortcomings of this process was to develop a self-adaptive algorithm with computer vision capabilities that adapts to the process in real-time. This experimental study highlights the results obtained using this method, as well as a comparison to a classical method for the stretch-forming process (SFP). The results have noted that the stretch-forming algorithm improves the process, while adapting its decisions with each step