European Journal of Formal Sciences and Engineering
European Journal of Formal Sciences and Engineering (EJFE) by Revistia, is an open access peer reviewed research journal. EJFE welcomes and acknowledges high quality theoretical and empirical original research papers in the field of Engineering and Formal Sciences, case studies, review papers, literature reviews, book reviews, conceptual framework, analytical and simulation models, technical note from researchers, academicians, professional and practitioners from all over the World.
The Effect of The Blade Pitch Angle of a Small-Scale Vertical Axis Wind Turbine on its Energy Output and Starting Performance
This study investigates the effect of blade pitch angle on energy output and start-up performance in a small-scale vertical-axis wind turbine. The angle of the blade pitch is an important design factor in wind turbines since it directly affects the aerodynamic forces. Therefore, different pitch angles can alter the turbine's efficiency and its ability to start operating independently. A small-scale wind turbine designed in a laboratory environment was used in the study. Experiments were conducted at three different blade pitch angles under constant wind conditions. Energy output was calculated by measuring the voltage and current values produced. Initial performance was evaluated based on the turbine's start-up time. Additionally, the results show a pitch angle increase of 5 to 10.72 degrees, which improves the efficiency of the system. Pitch angle increases from 5 to 10.72 degrees, increasing power output. The power output and the system's associated power efficiency both dropped between 10.72 and 20 degrees.
Vertical-axis wind turbine, blade pitch angle, aerodynamic performance, self-starting performance, power coefficient
Copyright (c) 2026 European Journal of Formal Sciences and Engineering https://creativecommons.org/licenses/by-nc-sa/4.0
Pulse Duration as the Gatekeeper of Temporal Resolution in Ultrafast Measurements of Electron Dynamics
This extended essay investigates the critical role of pulse duration in ultrafast laser systems and its influence on the temporal resolution of measurements regarding attosecond and femtosecond-scale electron dynamics. While the fundamental premise suggests that shortening pulse duration allows scientists to "freeze" electron motion, this research demonstrates that realized experimental resolution is not defined by pulse width alone. Instead, effective temporal resolution Δtₑff emerges from a complex quadrature sum of independent variables, including pump and probe durations, arrival-time jitter, and instrument response timing. Through a synthesis of theoretical frameworks—such as the time-energy uncertainty principle and the Fourier limit—and an analysis of techniques like tr-ARPES and Ultrafast Electron Diffraction (UED), the study highlights the inevitable trade-offs between temporal precision and energy resolution. The findings indicate that while pulse duration establishes the theoretical lower bound of resolution, practical advancement requires system-level engineering focused on synchronization and jitter suppression rather than pulse compression alone. Ultimately, the essay argues that achieving high-fidelity measurement is less about minimizing a single parameter and more about managing the total instrument function to accurately resolve the causal history of electronic processes.
Ultrafast laser systems, electron dynamics, temporal resolution, pulse duration, pump-probe spectroscopy, timing jitter, attosecond physics, time-energy uncertainty.
Copyright (c) 2025 European Journal of Formal Sciences and Engineering https://creativecommons.org/licenses/by-nc-sa/4.0
Modernizing Lean in the Automotive Industry: A Literature Review of Digitalization, Resilience, and Sustainability
Lean manufacturing has long been a central paradigm of efficiency and competitiveness in the automotive industry. However, the accelerating pressures of digital transformation, global supply chain disruptions, and sustainability imperatives are challenging and reshaping traditional lean practices. This literature review synthesizes recent scholarly research on lean manufacturing in the automotive sector, focusing on three critical themes: digitalization, resilience, and sustainability. Findings suggest that lean is no longer understood merely as a set of efficiency-oriented tools but as an evolving system that must integrate data-driven technologies, risk-management strategies, and environmental and human-centered concerns. The review highlights key tensions between efficiency and resilience, simplicity and digital complexity, and cost reduction and sustainability. It concludes with an integrative framework for lean’s modernization and identifies promising directions for future research in the automotive context.
lean manufacturing, automotive industry, digital transformation, supply chain resilience, sustainability, Industry 4.0, human-centered lean
The Second Great Disruption? Artificial Intelligence, Technological Unemployment, and Policies for a Resilient Workforce – A literature Review
Artificial intelligence (AI) is becoming a general-purpose technology, like the steam engine or electrification. However, it is being used more quickly than ever before. This makes it harder for businesses, workers, and governments to make changes in a short amount of time. Public discourse typically depicts AI as a driver of extensive displacement; however, empirical evidence suggests a more intricate path. AI is more likely to change how people do their jobs than to take away jobs altogether. This is true in many countries and industries. This article situates AI within the historical narrative of technological unemployment, incorporates recent data on exposure, skills demand, and job quality, and evaluates policy frameworks that can transform productivity potential into broadly shared advantages. The International Labour Organization (ILO), the Organisation for Economic Co-operation and Development (OECD), the World Economic Forum (WEF), LinkedIn workforce analytics, and the McKinsey Global Institute all say that clerical work is where most people come into contact with AI. A lot of workers say they are happier at work when they use AI, but not enough people have the right skills. The study shows a "complement-then-substitute" path: AI improves human skills at first, but it could eventually replace some jobs without immediate retraining. To keep inequality from getting worse, policy needs to make lifelong learning more common, protect workers, and encourage countries to work together..
job quality, social debate, lifelong learning, and technological unemployment
Minimizing Material Usage While Preserving Strength: Hybrid Genetic and Topology Optimization Approaches in Additive Manufacturing
Additive manufacturing technology has enabled the fabrication of intricate geometric constructs utilizing novel methodologies. Nonetheless, the optimization of material utilization while concurrently preserving structural integrity remains a pivotal technical endeavor. This investigation delves into the mathematical principles underlying topology optimization methodologies and their amalgamation with biomimetic lattice configurations. A comprehensive examination of four principal topology optimization methodologies—SIMP, BESO, Level Set, and ESO—is provided. An evaluative comparison of the advantages, disadvantages, and applications of each methodology is conducted. While SIMP demonstrates superiority in computational efficiency, BESO enhances the clarity of material boundaries. Level Set is useful for shapes that are hard to picture, while ESO is useful in the early stages of the design process. The study delves deeper into the traits of lattice structures inspired by natural forms and examines approaches to enhance their functional capabilities. Combining evolutionary algorithms with topology optimization is a good idea since it lets you search the entire design space while also making small improvements at the same time. The current literature indicates that the hybrid SIMP-GA methodology has attained roughly 7% enhanced compliance levels in comparison to conventional gradient-based strategies. This theoretical investigation integrates mathematical methodologies that optimize the efficiency of additive manufacturing while safeguarding structural integrity.
Topology optimization, additive manufacturing, biomimetic lattice structures, genetic algorithms, material efficiency, SIMP, BESO
The Relationship between Coal Consumption and Economic Growth in Indonesia
Indonesia is one of the largest coal producer countries in the world. In the previous research, it is stated that coal producer countries are able to affect economic growth. The purpose of the study is to investigate the co-integration and causal relationships between coal consumption and income in Indonesia for the period of 1965-2016 using Granger causality test based on Vector Error Correction Model (VECM) employing population as the control variable in bivariate system. The Augmented Dicky-Fuller (ADF) and Phillips-Perron (PP) tests were used to determine the variable stationarity. From Johansen’s co-integration tests, it is indicated that there is a long-run relationship between the variables. The empirical study shows that there is no causal relationship between coal consumption and economic growth in Indonesia since coal consumption in fact cannot affect economic growth in Indonesia. Export tax becomes government revenues earned from energy sectors including coal.
coal consumption, economic growth, causality, VECM, Indonesia
Copyright (c) 2021 European Journal of Engineering and Formal Sciences https://creativecommons.org/licenses/by-sa/4.0
Digital Competitiveness of European Union Member States from the Perspective of Human Capital
The concepts of "digital skills" and "digital competences" are key terms in the discussion related to the type of skills people need nowadays not only in terms of digital inclusion in the society but also in terms of employability. According to the latest definition by the European Union, digital skills “can be broadly understood as the ability to locate, organise, understand, evaluate, create and share information using digital technology, at different levels of competence” CITATION Eur171 \l 1033 (European Commission, 2017). The rapid development of information and communication technologies (ICT) bring major transformations with respect to the individual’s integration in society and employability. The paper analyses the 28 member states of the European Union (EU) from the perspective of the pesons’ digital skills and employability in the science, technology (including the ICT) sectors over the period 2015 - 2017. The paper covers the following areas of research: (1) Overall digital skills, computer skills, internet skills of individuals in the EU 28; (2) Human capital with advanced and specialist digital skills in ICTin the EU 28; (3) Evolution of the digital competitiveness of the EU 28 member states from the perspective of human capital over the period 2015-2017. Quantitative and qualitative research methods were employed for data collection and analysis: database research and analysis; statistical analysis; content and thematic research and analysis from policy papers and reports.
digital economy; digital society; digital skills; information and communication technologies
Vintage Design Furniture in Albania, a New Retro Design Paradigm in the Post-Communist Era
The dynamics of the Albanian market in lieu of the multifaceted transformations following the collapse of the communist regime and moving towards the accession processes in the European Union as well as the demographics of the Albanian society as a whole, deeply impact the ways in which furniture products are designed, development and produced. This paper draws from my doctoral study which explored the transformation of furniture products from communism to post-communism. The doctoral study confirmed that: the impact of moving from mass production in a centralized economy to free mass customization in market economy has not radically transformed the fundamental properties of furniture but has affected the design, development, delivery and materiality of products. In this light, this paper will zoom into the furniture designs during post communism in Albania by exploring two principle paradigms vintage and retro. First this paper argues that furniture design and production in the centralized economy, are introduced within the vintage paradigm in post-communist. The data collecting through observation demonstrate a high level of interest for the retro design in a free market economy. As the result the paper suggest the local actors, businesses and academia to use and persist nostalgia and retro design in furniture and their component.
vintage design, retro design, communist, post-communist.
Public Expenditures Through Public Procurement
Treaty of Rome of 1957 and following treaties on amending the Treaty of Rome contain a number of basic principles on which the EU is founded. Among these principles, the most important ones related to the public procurement are: prevention of discrimination based on nationality, free movement of goods; right and freedom of establishment of a business; the right to provide services. Spending of public money in Kosovo pursuant to the Law on Procurement is found on the following principles: economization and efficiency; equal treatment and non-discrimination; transparency; value for money. The average of open procedure application in EU countries is 73 percent based on notices, whereas in Kosovo is 82.80 percent based on notices. In the end of 2014, Kosovo commenced the development of electronic procurement platform. This project takes place within the Public Sector Modernization Project. The importance of the electronic procurement is stated in the statement of European Commission: “Modernization and opening of procurement markets across borders – including through the electronic procurement expansion – are crucial for the competition in Europe and creating new opportunities for businesses in EU”. A good procurement system in Kosovo will have an impact on elimination of negative phenomena (corruption and bad management) in the management of public expenditures from spending agencies, as well as an impact on increase of budget saving. Key words: public expenditures, value for money, bad management, procurement, electronic procurement.
words: public expenditures, value for money, bad management, procurement, electronic procurement.
Identification of Factors Causing Delays in Construction Projects in Algeria
Time is an indicator of project performance, and along with cost and quality factors, it is the project roadmap, as it determines its success. In Algeria, among the problems often encountered in the construction of projects are timeouts. A questionnaire survey was conducted with experts in the field of construction, in order to know the factors causing delays in projects. The results show that the managerial factors (relating to planning, organization and management) are the most important in Algeria. Therefore, the use of Project Management is essential, given the need to promote this area in terms of processes and tools used, to allow the various project stakeholders to optimize the planning of activities and resources, to complete the project. project in a timely manner and reach the stage of project success. Recommendations were proposed and managerial solutions were suggested using the guide of PMBOK version 5.
Construction project, deadlines, delay, project sucess, delay factors, project management, Algeria.
The Heteroscedasticity Impact on Actuarial Science: Lee Carter Error Simulation
C19 Life insurance companies deal with two fundamental types of risks when issuing annuity contracts: financial risk and demographic risk. As regards the latter, recent work has focused on modelling the trend in mortality as a stochastic process. A popular method for modelling death rates is the Lee-Carter model. In this paper we gives an overview of the Lee Carter model and the feasibility of using it to construct mortality forecast for the population data. In particular, we focus on a sensitivity issue of this model and in order to deal with it, we illustrate the implementation of an experimental strategy to assess the robustness of the LC model. The next step, we experiment and apply it to a matrix of mortality rates. The results are applied to a pension annuity. There are investigating in particular the hypothesis about the error structure implicitly assumed in the model speci?cation, after having assume that errors are homoscedastic. Analyzing the model it is estimated that the homoscedasticity assumption is quite unrealistic, because of the observed pattern of the mortality rates showing a different variability at different ages. Therefore, there is an emerging opportunity to analyze the strength of predictable parameter. The purpose of this study is a strategy in order to assess the strength of the Lee-Carter model inducing the errors to satisfy the homoscedasticity hypothesis. The impact of Lee Carter model on various financial calculations is the main focus of the paper. Furthermore, it is applied it to a matrix of mortality rates including a pension rate portfolio. The Albania model with the variables of death and birth is shown on this paper taken in consideration the Lee Carter Error.
words: Lee-Carter model, mortality forecasting, Life Expectancy at Birth, Experimental Strategy, Singular Value Decomposition (SVD), Homoscedasticity.
Copyright (c) 2018 European Journal of Engineering and Formal Sciences https://creativecommons.org/licenses/by-sa/4.0
Protection of Personal Data in Computerized Accounting Programs
One of the most vital accounting activities that businesses and organizations engage in is the essential planning and meticulous control of personal data collection and distribution. This task is particularly important in today's rapidly evolving landscape, where the nature of data management is constantly changing. The swift growth of new and innovative computer technologies has significantly influenced and transformed this crucial area of accounting practice. Computerized accounting programs are comprised of advanced and sophisticated software that effectively automates the entire accounting cycle, which in turn enhances both efficiency and accuracy in various financial record-keeping and reporting processes. As these advanced technologies continue to develop at an astounding pace, they not only streamline operations but also ensure compliance with ever-evolving regulations and improve overall data security. This results in the safeguarding of sensitive information, making it an indispensable component of modern accounting systems. In this study, a detailed research was conducted on the protection of personal data in computerized accounting programs.
computerized accounting, personal data protection, data security
Copyright (c) 2024 European Journal of Formal Sciences and Engineering https://creativecommons.org/licenses/by-nc-sa/4.0
The Use of Sawn Timber for Barrel Production from Oak Wood (Quercus Petraea L.)
The number of firms involved in the production of barrels from white oak (quercus petraea L,) is small. The production of wood barrels is quite complex and with a low exploitation coefficient. We think it is in the interests of firms to know how much the coefficient of use of sawn material for these types of products is. For the study we have chosen the firm "BehaN" in Rahovec, which mainly deals with the production of oak wood barrels. The sawn material taken in the study was of a good quality. To do the tests we used weighing methods, as its volume was difficult to measure since it was half milled. Tests were conducted for the production of barrel details with a volume of 50, 30 and 20 litters, which are most widely used by the costumers. For the realization used by the firm were taken into account the dimensions and technology. From the measurement data it turned out that the weight of the sawn timber was about 250kg. The results of these weights were exchanged in volume and percentage and they are shown in final results.
exploitation coefficient, plank, wood pieces, sawdust, barrel
Copyright (c) 2021 European Journal of Formal Sciences and Engineering https://creativecommons.org/licenses/by-sa/4.0
Statistical Process Control (SPC) and Quality Management Systems as a Specialty of Quality Management and Case Turkey
Concept of quality, quality assurance, quality policy and quality management have long since become indispensable in economic aspects. Quality management systems and their meaning are no longer discussed every now and then they have become reality and economic necessity. Also, in public administration, in politics, in education and in the non-profit sector, declarations of quality and their steering and securing are of fundamental importance. The general trend is higher expectations as to the quality of the most diverse products - whether physical products or services - is accompanied by the growing awareness that only through continuous and consistent improvements. A high product quality adds to satisfy the needs of the population. Therefore, the extraction of high-quality information based on the measurement technology. The measurement technology is integrated into the production process maximally strongly.
Total Quality Management, Quality in Industry, Quality Management Testing
Implementation of TQM in Manufacturing Industries of Developing Countries - Case Study: Albanian Companies
Manufacturing industry in Albania has been grown significantly over the last decades due to increased public demand, Government’s initiatives, and the investors increased interest in the manufacturing sector. Unfortunately, quality of product is still an important issue for the locally produced goods. Only a few manufacturers are producing high quality products with higher customer satisfaction. Many of them are holding quality certificates but a few has reached a stage of product development where they are able to apply modern quality principles and techniques effectively. Research on product quality improvement shows that meeting customer satisfaction, increasing profits and reducing losses to a minimum level can be attained through the application of modern quality philosophies and principles such as Total Quality Management (TQM). Understanding the tools and techniques of TQM is considered to be significant in order to get useful results. A better understanding is required to investigate the current status of TQM implementation. This research article presents a survey on current quality control practices within the manufacturing industries in Albania to assess the potentiality of implementing TQM technique and principles in order to improve the customer satisfactions and market share.
Quality, Total Quality Management, Albanian Manufacturing Industry
Design and Development of GSR Biofeedback Device
It has been a long time that human is interested in learning how to control involuntary actions such as heartbeat, blood pressure, breathing, etc., so a lot of research has been done on this issue so far. One of the methods using in this field is biofeedback, in which someone can roughly control an involuntary action or having better control over some voluntary actions such as muscle contraction through some visual or audio feedback from those actions. This study is to design and development of one biofeedback instrument, which is GSR (Galvanic Skin Response), and examine some signals that have been taken by this device.
Galvanic skin response (GSR), biofeedback, signal acquisition, relaxation training, lie detection1.
DLC Coatings on Spherical Elements of HIP Endoprostheses
Hard coatings are increasingly being used in medicine to protect metal endoprostheses The experimental process for the high-productive synthesis of high-quality diamond-like carbon (DLC) coatings with high hardness and a sufficiently high level of adhesion to the spherical shaped parts of the hip joint made from the stainless steel or cobalt-chrome alloy have been developed. DLC coating deposition was performed by vacuum-arc method from a high-productive source of the filtered vacuum-arc carbon plasma of rectilinear type with a "magnetic island". The high degree of thickness uniformity in the coating on the head of the hip joint with a high adhesion to the metal joint base was developed. Modernization of the vacuum arc plasma source allowed to accelerate the cathode spot motion, exclude substrate overheating and increase the diamond-like carbon hardness up to 30-40 GPa. The high adhesion level was achieved as a result of the high voltage pulsed of substrate bias potential use and multilayer architecture of DLC coating. The DLC coating on the heads of hip endoprosthesis did not peel off when boiling endoprosthesis or when immersing it into the liquid nitrogen. JEL O31
diamond-like carbon, head of hip joint, vacuum-arc, filtered plasma source, adhesion. 1.
Analysis of 5 Floor Brick Masonry Building, Type 77/5
This study investigates the seismic performance and structural improvement of a five-floor Type 77/5 brick masonry building through both linear and nonlinear analysis methods. The research employs finite element modeling using ETABS software for linear analysis and AM-Quake for nonlinear analysis to evaluate building performance against Eurocode standards. Initial findings revealed critical vulnerabilities, including excessive displacement (12.91 cm versus the allowable 7.1 cm) and periods of oscillation (0.688 sec versus the recommended 0.366 sec). Multiple reinforcement strategies were systematically tested, including concrete cladding, full concrete wall replacement, and fiber-glass reinforcement, with limited success. The study ultimately demonstrates that selective column implementation in the first two floors provides the most effective and economically viable solution, reducing displacement to 42.19 mm in the plastic phase and bringing the period within acceptable parameters. These findings have particular relevance in the context of Albania's seismic activity, as evidenced by the 6.3 Richter magnitude earthquake of November 26, 2019, and offer practical solutions for similar masonry structures requiring seismic reinforcement in regions with limited economic resources.
analysis, 5 floor brick, masonry building, type 77/5
Some Features of Seismicity in Leskovik-Korca-Oher Fault Zone During this Century
During this century, the Leskoviku-Korca-Oher fault zone seismicity is dominated by 7 moderate earthquakes with magnitude ML ranging 4.5 – 5.3. The database of this study composed of 2858 seismic events with ML >0.5 is characterized by tectonic earthquakes with b-value 0.76. Most of the earthquakes have magnitude ranging between 1.8 and 3.3. The cumulative number of earthquakes during two decades trends to increase. Furthermore, on the Leskoviku-Korca-Oher territory there are approximately 1392 earthquakes with magnitude ML ≥2.0, about 355 earthquakes ML ≥3.0 with average depth 11km, about 30 earthquakes ML ≥4.0 also 9 earthquakes ML ≥4.5 and 4 earthquakes ML ≥5.0. Statistics from 2001 to 2023 show that every year inside the Leskoviku-Korca-Oher territory occurs one earthquake with ML >4.0 and every 5 years occurs an earthquake with a magnitude of 5.1 to 5.3 Richter. A series of earthquakes of maximal magnitude (ML =5.3) started on June 01, 2019, at 04:26 (UTC), close to Floq village about 17 km south-west of Korça town expresses the increased seismic activity of the Leskovik-Korca-Oher seismogenic zone. We present results from statistics and analysis of focal mechanism of seismic events. The region affected enormous small earthquakes and by some moderate earthquakes during this century together with the strongest earthquake of the May 1960 ML= 6.2, forms a roughly N−S trending active seismotectonic zone in southeastern Albania which presents a threat to nearby urban areas from Albania, Greece and the North-Macedonia.
moderate earthquakes, series, focal mechanism, faults.
A Single Band Antenna Design for Future Millimeter Wave Wireless Communication at 38 GHz
In this proposed paper, a single band microstrip patch antenna for fifth generation (5G) wireless application was presented. 28, 38, 60 and 73 GHz frequency bands have been allocated for 5G mobile communications by International Telecommunications Union (ITU). In this paper, we proposed an antenna, which is suitable for the millimeter wave frequency. The single band antenna consists of new slot loaded on the radiating patch with the 50 ohms microstrip line feeding used. This single band antenna was simulated on a FR4 dielectric substrate have relative permittivity 4.4, loss tangent 0.02, and height 1.6 mm. The antenna was simulated by Electromagnetic simulation, computer software technology High Frequency Structural Simulator. And simulated result on return loss, VSWR, radiation pattern and 3D gain was presented. The parameters of the results well coherent and proved the literature for millimeter wave 5G wireless application at 38 GHz.
Single-band antenna, rectangle and cylindrical slots, millimeter wave, 5G
Composite Materials Behavior Analyze for Desk, Hull and Board Yacht's Panel
Materials science and composite technology are advancing rapidly, and new composites such as epoxy mixtures including the application of carbon nano tubes are becoming more popular with ever growing concern for high performance marine structures. Indeed, lightness, ease of production, durability and strength enable composites to play a vital role in marine applications. As the Marine sector continues to look at improving efficiency and reducing overall costs, Composite materials will play a huge part in the future of Marine construction. The paper is focused to the static linear simulation of elastic bodies using Solid Works Simulation. Stresses analyses have been developed in the static analyze which provide tools for the linear stress analysis of parts and assemblies loaded by static loads, taking in consideration for the analyze the most stressed part of the bottom, board and desk of the yachts Keywords: Static analyze, stress, composite materials, optimization, marine sector, leisure yachts.
Static analyze, stress, composite materials, optimization, marine sector, leisure yachts.
Copyright (c) 2020 European Journal of Formal Sciences and Engineering https://creativecommons.org/licenses/by-sa/4.0
Rockfall Analyses at Km 13+550 in the New Road of Vlora, Albania
Rockfall dynamics is a complex function of the location of the detachment point and the geometry and mechanical properties of both the block and the slope. Theoretically, knowing the initial conditions, the slope geometry, and the relationships describing the energy loss at impact or by rolling, it should be possible to compute the position and velocity of a block at any time. Nevertheless, relevant parameters are difficult to ascertain both in space and time, even for an observed event. Usually, the geometrical and geomechanically properties of the blocks (size, shape, strength, fracturing) and the slope (gradient, length and roughness, longitudinal and transversal concavities and convexities, grain size distribution, elastic moduli, water content, etc.), and the exact location of the source areas are unknown. In this paper, the sources of potential rock fallings involve a rocky area including between km 13+550 and km 13+600 in the new road of Vlora city in Albania. The area is characterized by a rock ridge, shaped like a dome, located few tens of meters above the design road. The purpose of this paper is the rock slope analysis. This analysis consists mainly of defining the sources of falling rocks, estimating the causes (by toppling, rock slides, single blocks) the size, the geometry, and type of blocks, the structural arrangement of joints, etc.
Slopes Analyses - Case Study, Slope Stability of Bypass Project
The scope of this study was to compare various stability evaluation methods. Accordingly, most common LE approaches were compared with the advanced LE (M?P) method. Similarly, the differences in FOS computed from LE and FE analyses were compared based on a simple slope considering various load cases. In addition, two real slopes in a case study were analysed for the recorded minimum?maximum GWT, pseudo?static and dynamic conditions. Moreover, the stability evaluations of these slopes were based on both LE (M?P) and FE (PLAXIS) calculation approaches, which both utilized shear strength parameters from advanced triaxle tests. Similarly, Mohr?Coulomb model was applied in both approaches. The following conclusions are hence derived based on the reported work on both idealized and real slopes. To fulfil one of the aims of the study, the LE based methods are compared based on the factor of safety (FOS) obtained for various load combinations. The comparison is mainly based on simplified slope geometry and assumed input parameters. Among the LE methods, the Bishop simplified (BS), Janbu simplified (JS) and Janbu GPS methods are compared with the Morgenstern?Price method (M?PM). These LE methods are well established for many years, and thus some of them are still commonly used in practice for stability analysis. Moreover, the M?PM has been compared with results from the FE analyses. Compared with theFE (PLAXIS) analyses, the LE (M?PM) analyses may estimate 5 – 14percent higher FOS, depending on the conditions of a dry slope and a fully saturated slope with hydrostatic pore pressure distributions. For fully saturated conditions in the slope, inaccurate computation of stresses in LE methods may have resulted in larger difference in the computed FOS. Since, the FE software is based on stress?strain relationship, stress redistributions are surely better computed even for a complicated problem. This has been found one of the advantages in FE simulations. A parameter study shows that the application of a positive dilatancy angle in FE analysis can significantly improve the FOS (4 ? 10percent). On contrast, the shear surface optimization in LE (M?PM in SLOPE/W) analysis results in lower FOS, and thus minimizing the difference in FOS compared with FE analysis
slope, stability, techniques, finite element analyses, stress
Fuzzy FMEA Application Combined with Fuzzy Cognitive Maps to Manage the Risks of a Software Project
The failure rate of an Information Technologies (IT) software project is pretty high because of their uncertain and risky structure. Managing well this kind of projects becomes important. Failure Mode and Effect Analysis (FMEA) is an extensive method that is used for identifying the importance level of risks in a project by using risk priority numbers (RPN). This method is based on experts’ experience and cognitive skills at gathering data in order to make risk assessment. This situation causes inaccurate conclusions in the final risk ranking. Fuzzy logic is widely integrated into FMEA to handle these inaccuracies and inconsistencies in the literature while making assessment and calling Fuzzy FMEA method that we proposed. In this study, we explored another uncovered weaknesses of the proposed method. FMEA and Fuzzy FMEA do not consider the relationships among the risks of a project. To overcome this disadvantage, we proposed to integrate the idea of cognitive maps into these two methods (FMEA w/FCMs and Fuzzy FMEA w/FCMs). Finally, we got a comprehensive risk assessment methodology by considering the relationships among the risks under ambiguous circumstances.
FMEA, Fuzzy logic, Fuzzy cognitive maps, Risk analysis.
An Analysis of Occupational Incidents, Prioritization of Factors Causing These by Using Multi Criteria Decision Making Methods and Identification of Ways for Reducing These: Case Study in Oil and Gas Fields
The aim of the Occupational Health and Safety studies conducted in the oil and gas sector is; to protect workers and to ensure occupational safety in works performed on drilling fields. The aforementioned studies of the companies operating in this field in Turkey are inadequate and are not given due importance to. In such companies, occupational incidents become inevitable for that reason. A vast number of studies have been conducted in many other countries around the world to reduce the number of occupational incidents, and those have led to a substantial reduction in those incidents. In Turkey, it is necessary to take measures to reduce the number of occupational incidents in the oil and gas sector. In this study, occupational incidents occurred in the company investigated as a case study and the other occupational incidents occurred in similar companies and the measures taken to reduce them have been discussed in detail. This study aims to explain what occupational incidents occur in the sector, what the root causes of them are and how to reduce the occupational incidents by taking measures.
Multi Criteria Decision Making, Occupational Health and Safety, Occupational Incident, Petroleum and Natural Gas Drilling.
Different Methods of Gas Turbine Engine Efficiency
The aviation industry faces mounting pressure to reduce fuel consumption, emissions, and noise pollution while maintaining or improving performance. This comprehensive review examines various methods and emerging technologies for enhancing conventional turbofan engine efficiency. The study analyzes multiple approaches, including advanced bypass ratio optimization, innovative gearbox systems, novel composite materials, and introduces a new twin-fan concept. Through systematic analysis of current literature and industry developments, this research demonstrates that significant improvements in engine efficiency can be achieved through the integration of multiple enhancement methods. The study particularly focuses on the relationships between bypass ratio modification, gearbox implementation, material selection, and their combined effects on fuel consumption, emissions, and noise reduction. The proposed twin-fan concept presents a novel approach to increasing air inlet efficiency while maintaining operational stability. Experimental data and theoretical analyses suggest that these combined approaches could potentially yield 15-20% improvement in fuel efficiency compared to conventional designs, while simultaneously reducing noise levels by 8-10 decibels.
turbofan, twin fan, engine, gas, turbine, efficiency, fuel, consumption
The main pillar of the Big Bang paradigm is the expansion of the Universe predicted by the cosmological redshift. Singularity is inevitable in the Big Bang model. The Universe is hyperbolic as we did prove mathematically; where the cosmological redshift is no longer a distance indicator. After all, in the hyperbolic spacetime a group of objects would grow apart even when not moving as their worldlines would be divergent. We show the manifold of the hyperbolic Universe is complete with no singular points. While the distance horizon in the Big Bang flat spacetime is finite, the distance horizon is infinite in the hyperbolic universe. The pillars of the big Bang and its consequences had been refuted and disproved or reinterpreted.
Big Bang, expanding universe, static universe, time dilation, distance horizon, nonsingularity.1.
Copyright (c) 2023 European Journal of Formal Sciences and Engineering https://creativecommons.org/licenses/by-sa/4.0
Memory of the Landscape and Ethical Dwelling
In this article, I intend to carry out a hermeneutic study into the relationship between the workings of memory and landscape, and the consequences that such a relationship produces for living on an ethical level. In the first part, I intend to highlight the active role played by memory in the significant interpretations of the landscape. In consideration of this aspect, I will deal with the circularity between building a narrative of the landscape and exercising individual and collective memory. In the second part, I will focus on the role that the narrative, together with memory, plays with regard to the different forms of living. In the light of such activity, living is seen as ethical dwelling for the care of the landscape and of man who inhabits it.
Memory, narrative, landscape, dwelling, care.
Europe’s Economic Crisis: Re - Clustering European Economies
National debt and distressed banks in countries such as Greece led to an ongoing recession since the beginning of Europe’s economic crisis. At the same time, austerity measures, all over Europe, reshape economies in a trial to increase global competitiveness. Economic integration as a challenge for social prosperity seems more crucial than ever, while it is a matter of research whether the acquired economic policies lead to further divergence. The paper explores how economic crisis has affected 40 European economies, by using macroeconomic indexes. A re-clustering of these economies is attempted for detecting similarities and differences between European economies. The analysis reveals how close an economic integration is and how a multi – speed European economy would look like today. Moreover, it explores how European economies have transformed during the last five years, in terms of competitiveness’ similarities and how the Gross National Income is related with governance indicators.
European Economies, Multi – Speed Europe, European Integration, Competitiveness, Gross National Income per Capita, Economic Convergence, Welfare.
Copyright (c) 2021 European Journal of Social Science Education and Research https://creativecommons.org/licenses/by-sa/4.0
Effectiveness of Active Confinement Techniques with Steel Ribbons: Masonry Buildings
In the present paper, we analyzed the main advantages of the active confinement techniques with a particular focus on the CAM system, which is an Italian reinforcement technique with pre-tensioned stainless steel ribbons. Italian seismic codes classify the CAM system as belonging to the strengthening category of “horizontal and vertical ties”. Therefore, we compared the CAM system to the reinforcement techniques with horizontal and vertical ties in order to understand the actual similarities and possible differences between them. Moreover, we offered a deep analysis of the main critical issues of the CAM system, distinguishing between geometrical and mechanical weak-points. In particular, we analyzed the strengthening mechanism of the CAM system, still poorly understood, by performing a static analysis in the Mohr/Coulomb plane. Finally, we provided suggestions for future developments.
CAM system, masonry walls, in-plane loading, out-of-plane loading.