bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Impact of Integrated Maintenance Actions Optimization on Strategic Machines Lifetime
Authors: Bensaci Mohammed Abdellatif , Hadjadj Aoul Elias 
Published: January 2021

Abstract
This article is based on the quantitative study of reliability, maintainability, availability (RMA), on the Pareto diagram (ABC) and on the analysis of the failure modes and their impact on criticality (FMECA). The developed approach aims, at first, implementing two optimization procedures (code development, Simulink modelling in MATLAB) and using two methods (graphical, analytic) of the Weibull parameters. The results obtained via code (which is based on the Weibull graph method of two parameters) are a bit divergent. The evaluation criteria are rather far from that of the model (which is based on the maximum likelihood of three-parameter Weibull distribution). This will allow to locate the critical elements, and to determine the systematic preventive time of replacements. An application case validates the proposed study objective.
Study of Reliability in a Repairable System by Markov Chains
Authors: Tamaloussi Naima , Bouzaouit Azzedine 
Published: January 2021

Abstract
In the industrial sector, maintenance of production facilities plays an important role to carry out production by increasing the reliability and availability of the production process. Predictive maintenance strategy seems adequate to anticipate the failure and degradation of the state of such equipment. A reliability study is needed to quantify indicators to describe the functioning of any system over time. In this paper, we present the results of a stochastic modeling conducted on the analysis of the availability of motor-pump system, installed in a cooling circuit in an industrial complex. The equipment considered in this study is composed of four subsystems. The proposed model is a dynamic Markovian approach, for the purpose of a comparison with the analytical calculation in terms of the indicators’ evaluation of the dependability of the studied system, including instant availability. The different states of the system components and the transition functions between these states have also been characterized. The results of availability obtained by the model are well correlated with those calculated analytically, confirming that the proposed model is very powerful, it will help predict the future states of the system, in order to predict any necessary preventive maintenance actions.
Improvement of the Hammer Drill Performance (Algerian Quarries Conditions)
Authors: Nemouchi Samia , Aoul Elias Hadjadj 
Published: January 2021

Abstract
The factors which influence the performance characteristics of a hammer drill are examined; drilling data are analyzed to determine these factors. Methods for selecting the appropriate drilling are also highlighted. Two models are used in order to compare optimal drilling parameters. The main one is the machine output.
Preface
Authors: Karaivanova Aneta , Margenov Svetozar 
Published: January 2021

Abstract
We are pleased to present the special issue “New developments in scalable computing” of the scientific journal “Cybernetics and Information Technologies”. For this issue (Volume 20, No 6 – December 2020), we have selected 19 papers which have gone through peer review and represent novel results in the field of Scalable Computing using state-of-the-art high-performance computing infrastructures.
Performance Optimization System for Hadoop and Spark Frameworks
Authors: Astsatryan Hrachya , Kocharyan Aram , Hagimont Daniel , Lalayan Arthur 
Published: January 2021

Abstract
The optimization of large-scale data sets depends on the technologies and methods used. The MapReduce model, implemented on Apache Hadoop or Spark, allows splitting large data sets into a set of blocks distributed on several machines. Data compression reduces data size and transfer time between disks and memory but requires additional processing. Therefore, finding an optimal tradeoff is a challenge, as a high compression factor may underload Input/Output but overload the processor. The paper aims to present a system enabling the selection of the compression tools and tuning the compression factor to reach the best performance in Apache Hadoop and Spark infrastructures based on simulation analyzes.
New Uniform Subregular Parallelisms of PG(3, 4) Invariant under an Automorphism of Order 2
Authors: Betten Anton , Topalova Stela , Zhelezova Svetlana 
Published: January 2021

Abstract
A spread in PG(n, q) is a set of lines which partition the point set. A parallelism is a partition of the set of lines by spreads. A parallelism is uniform if all its spreads are isomorphic. Up to isomorphism, there are three spreads of PG(3, 4) – regular, subregular and aregular. Therefore, three types of uniform parallelisms are possible. In this work, we consider uniform parallelisms of PG(3, 4) which possess an automorphism of order 2. We establish that there are no regular parallelisms, and that there are 8253 nonisomorphic subregular parallelisms. Together with the parallelisms known before this work, this yields a total of 8623 known subregular parallelisms of PG(3, 4).
Two-Stage Search-Based Approach for Determining and Sorting of Mountain Hiking Routes Using Directed Weighted Multigraph
Authors: Dimitrova Zornitsa , Dimitrov Vasil , Borissova Daniela , Garvanov Ivan , Garvanova Magdalena 
Published: January 2021

Abstract
The mountain hiking destinations become more popular as this is one of the possible ways to cope with workplace stress and to prevent burnout. In contrast to the tourist destinations, mountain hiking requires special attention due to the variety of mountain trails satisfying the same starting and finishing point for a particular route. For the goal, a two-stage search-based approach for a determining of possible routes considering the users’ preferences is developed. The first stage is focused on the determining of possible hiking routes taking into account the requirements and tourists’ preferences, while the second stage concerns the sorting of already determined hiking routes. The applicability of the described approach is illustrated and the obtained results demonstrate the capability in searching and sorting of mountain hiking trails using directed weighted multigraph including tourists’ preferences.
New Local Search Procedure for Workforce Planning Problem
Authors: Fidanova Stefka , Luque Gabriel 
Published: January 2021

Abstract
Optimization of workforce planning is important for any production area. This leads to an improvement in production process. The aim is minimization of the assignment costs of the workers, who will do the jobs. The problem is to select and assign employers to the jobs to be performed. The constraints are very strong, coming both from the specifics of the production process and from the legislation. Sometimes it is difficult to find feasible solutions. The complexity of the problem is very high and the needed number of calculations is exponential, therefore only specially developed algorithms can be applied. The objective is to minimize the assignment cost, while respecting all requirements. We propose a new hybrid metaheuristic algorithm to solve the workforce-planning problem, which is a combination between Ant Colony Optimization (ACO) and suitable local search procedure.
Performance Analysis of a Scalable Algorithm for 3D Linear Transforms on Supercomputer with Intel Processors/Co-Processors
Authors: Lirkov Ivan 
Published: January 2021

Abstract
Practical realizations of 3D forward/inverse separable discrete transforms, such as Fourier transform, cosine/sine transform, etc. are frequently the principal limiters that prevent many practical applications from scaling to a large number of processors. Existing approaches, which are based primarily on 1D or 2D data decompositions, prevent the 3D transforms from effectively scaling to the maximum (possible/available) number of computer nodes. A highly scalable approach to realize forward/inverse 3D transforms has been proposed. It is based on a 3D decomposition of data and geared towards a torus network of computer nodes. The proposed algorithms requires compute-and-roll time-steps, where each step consists of an execution of multiple GEMM operations and concurrent movement of cubical data blocks between nearest neighbors. The aim of this paper is to present an experimental performance study of an implementation on high performance computer architecture.
On Dynamic Parallelization of Multilevel Monte Carlo Algorithm
Authors: Shegunov Nikolay , Iliev Oleg 
Published: January 2021

Abstract
MultiLevel Monte Carlo (MLMC) attracts great interest for numerical simulations of Stochastic Partial Differential Equations (SPDEs), due to its superiority over the standard Monte Carlo (MC) approach. MLMC combines in a proper manner many cheap fast simulations with few slow and expensive ones, the variance is reduced, and a significant speed up is achieved. Simulations with MC/MLMC consist of three main components: generating random fields, solving deterministic problem and reduction of the variance. Each part is subject to a different degree of parallelism. Compared to the classical MC, MLMC introduces “levels” on which the sampling is done. These levels have different computational cost, thus, efficiently utilizing the parallel resources becomes a non-trivial problem. The main focus of this paper is the parallelization of the MLMC Algorithm.
Geometrically Non-Linear Vibration of a Cantilever Interacting with Rarefied Gas Flow
Authors: Shterev Kiril , Manoach Emil 
Published: January 2021

AbstractThe work is devoted to study 2D pressure driven rarefied gas flow in a microchannel having an elastic obstacle. The elastic obstacle is clamped at the bottom channel wall and its length is half of the channel height. The gas flow is simulated by Direct Simulation Monte Carlo (DSMC) method applying the advanced Simplified Bernoulli Trial (SBT) collision scheme. The elastic obstacle is modelled as geometrically nonlinear Euler Bernoulli beam. A reduced 3 modes reduction model of the beam is created. The influence of the gas flow on the beam vibration is studied, considering the linear and nonlinear beam theories.
Molecular Dynamics Simulations of Acetylcholinesterase – Beta-Amyloid Peptide Complex
Authors: Atanasova Mariana , Dimitrov Ivan , Ivanov Stefan 
Published: January 2021

Abstract
Alzheimer’s Disease (AD) is a neurodegenerative disorder with severe consequences and lethal outcome. One of the pathological hallmarks of the disease is the formation of insoluble intercellular beta-Amyloid (Aβ) plaques. The enzyme ACetylcholinEsterase (AChE) promotes and accelerates the aggregation of toxic Aβ protofibrils progressively converted into plaques. The Peripheral Anionic Site (PAS), part of the binding gorge of AChE, is one of the nucleation centers implicated in the Aβ aggregation. In this study, the Aβ peptide was docked into the PAS and the stability of the formed complex was investigated by molecular dynamics simulation for 1 μs (1000 ns). The complex was stable during the simulation. Apart from PAS, the Aβ peptide makes several additional contacts with AChE. The main residence area of Aβ on the surface of AChE is the region 344-361. This region is next to PAS but far enough to be sterically hindered by dual-site binding AChE inhibitors.
Trend Analysis of CMIP5 Ensemble of Climate Indices over Southeast Europe with Focus on Agricultural Impacts
Authors: Chervenkov Hristo , Gadzhev Georgi , Ivanov Vladimir , Ganev Kostadin 
Published: January 2021

Abstract
Nowadays there is a strong degree of agreement that the climate change is the defining challenge of our time, which will exert influence on the ecosystems, on all branches of the international economy and on the quality of life. The analysis based on climate indices is widely used non-parametric approach for quantification of the mean state as well as extreme climate events. This study, which is continuation of our previous efforts, is dedicated to the assessment of the trend magnitude and the trend statistical significance of six temperature-based and three precipitation-based indices in projected future climate over Southeast Europe up to the end of the 21st century. The indices are computed from the bias-corrected output of five CMIP5 global models, reinforced with all four RCP emission scenarios. The model output is accessed from the section of the Inter Sectoral Impact Model Intercomparison Project in the Copernicus Data Store. The multi model ensemble medians of the temperature-based indices shows considerable increase which is consistent with the warming of the mean temperatures. These changes are statistically significant in most cases and intensify with the radiative forcing. The revealed tendencies of the precipitation-based indices are more complex when compared with temperature tendencies.
Degree-Day Climatology over Central and Southeast Europe for the Period 1961-2018 – Evaluation in High Resolution
Authors: Chervenkov Hristo , Ivanov Vladimir , Gadzhev Georgi , Ganev Kostadin , Melas Dimitrios 
Published: January 2021

Abstract
The ongoing climate change over Central and Southeast Europe has a great potential to affect significantly the public energy demands and in particular the energy consumption in the residential heating and cooling sector. The linkage of the ambient daily extreme and mean temperatures and the energy needs for condition or heat buildings can be quantified as numerical indicators as the heating and cooling degree-days. In the present study, these indicators are calculated according the UK Met Office methodology from the daily mean and extreme temperatures, which, in turn, are computed from the output of the MESCAN-SURFEX system in the frame the FP7 UERRA project. The study, which is performed in a very high resolution, is dedicated on the analysis of the spatial patterns as well as assessment of the magnitude and statistical significance of the temporal evolution of the heating and cooling degree-days. It reveals general tendencies which are coherent with the regional climate warming, but with high spatial heterogeneities. The study confirms the essential impact of the ongoing climate change on the heating, ventilating and air-conditioning industry over Central and Southeast Europe.
Design of Multi-Epitope Vaccine against SARS-CoV-2
Authors: Doytchinova Irini , Tchorbanov Andrey 
Published: January 2021

Abstract
The ongoing COVID-19 pandemic requires urgently specific therapeutics and approved vaccines. Here, the four structural proteins of the Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2), the causative agent of COVID-19, are screened by in-house immunoinformatic tools to identify peptides acting as potential T-cell epitopes. In order to act as an epitope, the peptide should be processed in the host cell and presented on the cell surface in a complex with the Human Leukocyte Antigen (HLA). The aim of the study is to predict the binding affinities of all peptides originating from the structural proteins of SARS-CoV-2 to 30 most frequent in the human population HLA proteins of class I and class II and to select the high binders (IC50 < 50 nM). The predicted high binders are compared to known high binders from SARS-CoV conserved in CoV-2 and 77% of them coincided. The high binders will be uploaded onto lipid nanoparticles and the multi-epitope vaccine prototype will be tested for ability to provoke T-cell mediated immunity and protection against SARS-CoV-2.
Immunoinformatic Analysis of Human Thyroglobulin
Authors: Doytchinova Irini , Tchorbanov Andrey , Ivanov Stefan 
Published: January 2021

Abstract
The AutoImmune ThyroiDitis (AITD), known as Hashimoto’s disease, is a chronic autoimmune thyroid disease progressively developed to hypothyroidism. The AITD is characterized by the formation of autoantibodies targeting two specific thyroid antigens, Thyroglobulin (Tg) and Thyroid PerOxidase (TPO). Tg is a precursor of the thyroid hormones while TPO catalyses their synthesis. The AITD has a strong genetic predisposition. During the last years, it was found that the susceptibility to AITD is associated with certain Human Leukocyte Antigens (HLA) class II genes of loci DR and DQ. In the present study, we applied in-house immunoinformatic tools to identify peptides originating from Tg and binding to AITD susceptible alleles: HLA-DR3, HLA-DR4, HLA-DR5, HLA-DQ2 and HLA-DQ8. Five peptide fragments containing promiscuous overlapping binders were selected. These were p470, p949, p1948, p2348 and p2583. Only one of them contains a known epitope (p1948). The rest have not been reported yet. The selected peptide fragments will be coupled to monoclonal antibodies specific to inhibitory B cell receptors designed to suppress the production of Tg autoantibodies.
Anti-Fraud Strategy
Authors: Todorović Zdravko , Tomaš Darko , Todorović Boris 
Published: January 2021

Abstract
Fraud is not an individual problem, but rather, we deal with a systematic fraud, particularly in the public sector through the creation of a private monopoly over public sector. Therefore, the first step, which needs to be set in organization in order to develop an efficient system for fraud control is development of anti-fraud strategy. Anti-fraud strategy is based on a policy of integrity and zero tolerance for fraud. Under the fraud we imply: corruption, assets misappropriation and fraudulent statement. Fraudsters are in the organization and beyond. Factors influencing performing of fraud are: pressure, opportunity and rationalization. Costs incurred due to the fraud may be difficult to realistically consider. Battle against fraud is determined by political will, effective legislation and anti-fraudulent culture and strategy.
Analysis of Okun’s Regularity: The Case of Bosnia and Herzegovina
Authors: Erić Ognjen , Popović Goran , Bjelić Jelena 
Published: January 2021

Abstract
Economic growth, or, more precisely, GDP growth rate (Y) is the key macroeconomic indicator. Positive tendencies of GDP growth (r) mostly impact the economic welfare of the national economy. Hence, output is analysed in combination with other macroeconomic aggregates and indicators: investments, inflation, unemployment, trade exchange and the like. In the context of researching the relation between GDP trends and unemployment rate, A.M. Okun was the first to notice regularity between these variables. Okun’s law shows the direction and strength of GDP changes under the influence of (un)employment and represents functional relation between the output market and labour market. This paper aims to prove that, to a certain extent, there exists Okun’s regularity in Bosnian and Herzegovinian economy for the period of 2000-2019. The results of linear regression analysis show that there is negative correlation (R=0,451) between variables Y (output) and X (unemployment). Determination coefficient R2 = 0,204 indicates that 20,4% variations in GDP is determined by the changes in unemployment. Coefficient β in linear regression equation is negative, amounting to -0,596, which means that a change in unemployment by 1 percentile point brings about an inverse change in GDP by approximately 0,6 units. Variable direction indicates that there exists Okun’s regularity, though with significantly weaker intensity among the variables. This proves the hypothesis that there is a negative functional relation between the output market and labour market in Bosnia and Herzegovina.
Factors Affecting Precision Agriculture Adoption: A Systematic Litterature Review
Authors: Yatribi Taoufik 
Published: January 2021

Abstract
The aim of this paper is to present the main advances in the adoption of precision agriculture technologies. While we are witnessing the emergence of a literature dedicated to the adoption of new technologies, this theme still suffers from a lack of consensus on its conceptualization. Based on the prisma statement method (Preferred Reporting Items for Systematic Reviews and Meta-Analyzes), the objective is to carry out a review of the systemic literature in order to identify the main factors of adoption of the technologies of precision agriculture over the past ten years. The results show that individual factors are the most empirically identified as determining factors in the adoption of precision agriculture technologies. That said, the farmer is at the center of the adoption decision. Perceived utility is the factor most identified in the literature as the determinant of adoption.
The Role of Organizational Culture in Commitment to Implement Total Quality Management (Case Study of Algerian Public Companies)
Authors: Mohamed Fellague 
Published: January 2021

Abstract
The management in TQM implies that it‘s a management approach, not just a narrow quality control or quality assurance function. Some principles and practices of TQM may differ among firms and industries, but there is unanimous agreement as to the importance of organizational culture in implementing TQM. Accordingly the objective of the paper is to empirically investigate the relationship between organizational culture and the implementation of TQM. This study limited to public companies in Algeria. The sample of study consisted (107) executives and managers who are working under functional heads. We used convenience sampling in selecting the subjects. The instrument used in the study was a survey questionnaire. The Correlation analysis explained a positive moderate relationship between organizational culture and implementation of TQM (r=0.580, p=0.000) that is culture of a (Algerian public companies) is positively related to the implementation of TQM.
The study recommended increasing the interest in improving the availability levels of the organizational culture dimensions in general; and place a particular focus on the relatively low level dimensions, and the necessity to take into account realizing coherence among these dimensions in terms of the closeness of the availability levels, and lessening the deviations among these dimensions as well as among the elements of the same one dimension, due to the integrative nature among them. The study further recommended assimilating the organizational culture concept as an administrative concept by the managerial executives in the Algerian public companies, being an important foundation, upon which the success or failure of applying the TQM depends.