Search

In this paper we study the following problem (Problem 4.2 in, I.A. Rus, Sets with structure, mappings and fixed point property: fixed point structures, Fixed Point Theory 23, No. 2 (2022), 689-706):

In this paper we extend some results of V. Berinde, Şt. Măruşter and I.A. Rus (Saturated contraction principles for nonself operators, generalizations and applications, Filomat, 31:11(2017), 3391-3406), which were given in metric spaces, to Kasahara spaces. Some research directions are also presented.

In this paper we study the following problems: I. Let (M, d) be a complete metric space and f, g : M → M be two operators. We suppose that:

Let (X, d) be a metric space, f: X → X be a mapping and G(., f(.)) be an admissible perturbation of f. In this paper we study the following problems: In which conditions imposed on f and G we have the following: (DDE) data dependence estimate for the mapping f perturbation; (UH) Ulam-Hyers stability for the equation, x = f(x); (WP) well-posedness of the fixed point problem for f; (OP) Ostrowski property of the mapping f. Some research directions are suggested. [ABSTRACT FROM AUTHOR]

The hydrophilic vegetation from reservoir deltas sustains rapid expansions in surface and important increases in vegetal mass against a background of a significant influx of alluvium and nutrients from watercourses. It contributes to reservoir water quality degradation and reservoir silting due to organic residues. In this paper, we propose an evaluation method of two-dimensional and three-dimensional parameters (surfaces and volumes of vegetation), using the combined photogrammetric techniques from the UAS category. Raster and vector data—high-resolution orthophotoplan (2D), point cloud (pseudo-LIDAR) (3D), points that defined the topographic surface (DTM—Digital Terrain Model (3D) and DSM—Digital Surface Model (3D))—were the basis for the realization of grid products (a DTM and DSM, respectively). After the successive completion of the operations within the adopted workflow (data acquisition, processing, post-processing, and their integration into GIS), after the grid analysis, the two proposed variables (topics) of this research, respectively, the surface of vegetation and its volume, resulted. The data acquisition area (deriving grids with a centimeter resolution) under the conditions of some areas being inaccessible using classical topometric or bathymetric means (low depth, the presence of organic mud and aquatic vegetation, etc.) has an important role in the reservoirs' depth dynamics and reservoir usage. After performing the calculations in the abovementioned direction, we arrived at results of practical and scientific interest: Cut Volume = 196,000.3 m3, Cut 2D Surface Area = 63,549 m2, Fill Volume = 16.59998 m3, Fill 2D Surface Area = 879.43 m2, Total Volume Between Surfaces = 196,016.9 m3. We specify that this approach does not aim to study the vegetation's diversity but to determine its dimensional components (surface and volume), whose organic residues participate in mitigating the reservoir functions (water supply, hydropower production, flash flood attenuation capacity, etc.). [ABSTRACT FROM AUTHOR]

In this paper we consider the following problems:

This paper presents research in the field of estimating and assessing occupational risks, in order to secure the activities carried out in the presence of specific hazards of industrial work systems, and is based on an in-depth knowledge of interdisciplinary notions in various fields related to systems security engineering. The innovative methodological tool highlights a way to quantify the phenomenon of manifestation of hazards specific to work processes that generate occupational risks with impact, both on the human component and at the level of other components specific to work systems, which significantly reduces the inherent subjectivity in assessing the risks caused by the human factor.

Banks in Romania offers its customers a wide range of products but which involves both risk taking. Therefore researchers seek to build rating models to help managers of banks to risk of non-recovery of loans and interest. In the following we highlight rating Raiffeisen Bank, BCR-ERSTE Bank and Transilvania Bank, based on the models CAAMPL and Stickney making a comparative analysis of the two rating models.

As a result of the combustion of coal in the Paroseni Thermal Power Plant, large amounts of slag and ash waste are produced. Slag and ashes are deposited in the Caprisoara Valley slag and ash deposits. Upon completion of the deposit process, these landfills must be cleaned and reintroduced in natural circuit. An important step in the process of reintroduction in natural circuit of the deposits of slag and ashes is the implementation of some methods of revegetation. The chosen method must respect the main objectives of an environmental management system. In this paper we will present a method for managing the process of revegetation of the slag and ash deposits in order to reintroduce affected areas into the natural circuit.

In this paper we present some suggestions for unifying the terminology of the mappings appearing in fixed point iterative methods for the case when the setting is a metric space. We consider the following concepts: contraction type mapping, contractive type mapping and nonexpansive type mapping, for which some problems are formulated. [ABSTRACT FROM AUTHOR]

The assessment of changes in forest coverage is crucial for managing protected forest areas, particularly in the face of climate change. This study monitored forest cover dynamics in a 6535 ha mountain area located in north-west Romania as part of the Apuseni Natural Park from 2003 to 2019. Two approaches were used: vectorization from orthophotos and Google Earth images (in 2003, 2005, 2009, 2012, 2014, 2016, 2017, and 2019) and satellite imagery (Landsat 5 TM, 7 ETM, and 8 OLI) pre-processed to Surface Reflectance (SR) format from the same years. We employed four standard classifiers: Support Vector Machine (SVM), Random Forest (RF), Maximum Likelihood Classification (MLC), Spectral Angle Mapper (SAM), and three combined methods: Linear Spectral Unmixing (LSU) with Natural Breaks (NB), Otsu Method (OM) and SVM, to extract and classify forest areas. Our study had two objectives: (1) to accurately assess changes in forest cover over a 17-year period and (2) to determine the most efficient methods for extracting and classifying forest areas. We validated the results using performance metrics that quantify both thematic and spatial accuracy. Our results indicate a 9% loss of forest cover in the study area, representing 577 ha with an average decrease ratio of 33.9 ha/year−1. Of all the methods used, SVM produced the best results (with an average score of 88% for Overall Quality (OQ)), followed by RF (with a mean value of 86% for OQ). [ABSTRACT FROM AUTHOR]

Let (X, d) be a complete metric space, (Y, ρ) be a metric space and f, g : X → Y be two mappings. The problem is to give metric conditions which imply that, C(f,g) : = {x ∈∈ X \ f(x) = g(x)} ≠ 0. In this paper we give an abstract coincidence point result with respect to which some results such as of Peetre-Rus (I.A. Rus, Teoria punctului fix în analiza funcțională, Babeş-Bolyai Univ., Cluj-Napoca, 1973), A. Buică (A. Buică, Principii de coincidență şi aplicații, Presa Univ. Clujeană, Cluj-Napoca, 2001) and A.V. Arutyunov (A.V. Arutyunov, Covering mappings in metric spaces and fixed points, Dokl. Math., 76(2007), no.2, 665-668) appear as corollaries. In the case of multivalued mappings our result generalizes some results given by A.V. Arutyunov and by A. Petruşel (A. Petruşel, A generalization of Peetre-Rus theorem, Studia Univ. Babeş-Bolyai Math., 35(1990), 81-85). The impact on metric fixed point theory is also studied. [ABSTRACT FROM AUTHOR]

The increase in the number of electric vehicles in the coming years is a challenge in the management of used batteries. At the same time, recycling used batteries is an opportunity for both waste processors and battery manufacturers. Used Li-ion batteries are a secondary source of very valuable materials. Recycling results in a number of deficient and expensive elements such as cobalt and lithium. Automating battery disassembly reduces costs leading to economically viable recycling and influences the efficiency of the separation processes and the purity of the resulting elements. The utilization of useful elements produces technological, economic and ecological effects. [ABSTRACT FROM AUTHOR]