1. Optimising energy piles: a multi-objective approach to cost and failure probabilityRok Varga, Primož Jelušič, Bojan Žlender, 2025, original scientific article Abstract: This paper presents a comparative analysis of the influence of thermal loading on the design of optimally designed floating energy piles in soft consistency soils using a genetic algorithm. The nonlinear settlement of energy piles is also considered. The deterministic optimisation model (OPT-EP) includes a cost objective function constrained by design constraints and is later extended to include the probability of failure as a second objective function to perform multi-objective optimisation. This extension was undertaken because the Eurocode 7 approach only partially accounts for uncertainties in the soil, whereas the reliability-based design (RBD) approach fully exploits these uncertainties. Consequently, a multi-objective optimisation (cost vs. failure probability) was carried out in this study. The optimal designs obtained by the two different optimisation methodologies were further analysed and it was found that when the Eurocode 7 safety factor approach was used, the conditions related to thermal loading were not crucial for the design values. On the other hand, the multi-objective optimisation based on the RBD approach showed that the thermal loading affected the design, proving the usefulness of the multi-objective optimisation and the reliability-based design.
Keywords: energy pile, multi-objective optimisation, reliability-based design, genetic algorithm
Published in DKUM: 04.04.2025; Views: 0; Downloads: 5
 Full text (2,28 MB)
This document has many files! More... |
2. Psychometric testing of the Slovene version of the Perceived Inventory of Technological Competency as Caring in NursingCvetka Krel, Dominika Vrbnjak, Gregor Štiglic, Sebastjan Bevc, 2024, original scientific article Abstract: The Perceived Inventory of Technological Competency as Caring in Nursing (PITCCN) questionnaire has been designed to measure technological competency as caring in nursing practice. It incorporates the use of technology with the fundamental principles of caring that are central to nursing. As there were no psychometrically sound instruments to quantify the concept of technological competency as caring in the Slovene language, we adapted the English version of the questionnaire to the local environment. The goal was to assess the level of psychometric properties of the PITCCN investigated in Slovene hospitals. Methods: Content validity was conducted with eight experts and quantified by the content validity index (CVI) and the modified Cohen’s kappa index. Face validity was assessed through discussions with participants from the target culture in the pilot study. To assess construct validity and internal consistency, a cross-sectional research methodology was used on a convenience sample of 121 nursing personnel from four hospitals. Principal component analysis (PCA) was used to examine construct validity, while Cronbach’s alpha and adjusted item-total correlations were used to measure internal consistency. Results: The content and face validity of PITCCN were adequate. The scale validity index (S-CVI) was 0.97. Cronbach’s α was 0.92, and subscale reliabilities ranged from 0.810 to 0.925. PCA showed four components, which explained more than 73.49% of the variance. Conclusions: The Slovenian version of PITCCN (PITCCN_SI) has good psychometric properties.
Keywords: technology, caring, reliability, validity, psychometric properties
Published in DKUM: 28.03.2025; Views: 0; Downloads: 5
Full text (265,87 KB)
This document has many files! More... |
3. CAE artificial neural network applied to the design of incrementally launched prestressed concrete bridgesTomaž Goričan, Milan Kuhta, Iztok Peruš, 2025, original scientific article Abstract: Bridges are typically designed by reputable, specialized engineering and design companies with years of experience. In these firms, experienced engineers share and pass on their knowledge to younger colleagues. However, when these experts retire, some of the knowledge is lost forever. As a subset of artificial intelligence methods, artificial neural networks (ANNs) can solve the problem of acquiring, transferring, and preserving specialized expert knowledge. This article describes the possible application of CAE ANN to acquire knowledge and to assist in the design of incrementally launched prestressed concrete bridges. Therefore, multidimensional graphs in the form of iso-curves of equal values were created, allowing practicing engineers to understand complex relationships between design parameters. The graphs also contain information about the reliability of the results, which is defined by an estimated parameter. The general rule is that results based on a larger number of actual data points are more reliable. Finally, an ANN BD assistant is proposed as an application that assists engineers and designers in the early stages of design and/or established engineers and designers in variant studies and design parameter optimization.
Keywords: artificial neural networks, bridge design, incremental launching method, expert knowledge, reliability of predictions, prestressed concrete bridges
Published in DKUM: 10.03.2025; Views: 0; Downloads: 12
Full text (5,54 MB)
This document has many files! More... |
4. Napredne kvantitativne raziskovalne metode v zdravstveni negiLucija Gosak, Leona Cilar Budler, Roger Watson, Gregor Štiglic, 2025 Abstract: Publikacija "Napredne kvantitativne raziskovalne metode v zdravstveni negi" daje študentom zdravstvene nege in medicinskim sestram znanje in spretnosti za razlago različnih statističnih metod na njihovem področju, kar lahko izboljša spretnosti uporabnikov pri zbiranju, analizi in razlagi rezultatov iz klinične prakse ter tako prispeva k izboljšanju kakovosti zdravstvene oskrbe. Vsebuje podrobna navodila za uporabo programa IBM SPSS in izvajanje statističnih analiz, ki jih morajo medicinske sestre poznati pri svojem delu, saj pri vsakodnevnem delu s pacienti uporabljajo in ustvarjajo podatke. Glavni cilj zdravstvene nege pacientov je zagotavljanje kakovostne in na dokazih temelječe zdravstvene nege, zato so medicinske sestre dolžne slediti najnovejšim raziskavam in dokazom ter jih uporabljati pri svojem delu. Znanje, pridobljeno v tej knjigi, lahko medicinskim sestram pomaga tudi pri boljšem razumevanju in interpretaciji predhodno objavljenih rezultatov ter s tem pri kritični presoji veljavnosti in zanesljivosti rezultatov, ki jih bodo uporabljale v klinični praksi.
Keywords: quantitative analysis, statistics, IBM SPSS, reliability, validity, data analysis
Published in DKUM: 28.01.2025; Views: 0; Downloads: 23
Full text (18,57 MB)
This document has many files! More... |
5. Optimization of embedded retaining walls under the effects of groundwater seepage using a reliability-based and partial factor design approachRok Varga, Bojan Žlender, Primož Jelušič, 2024, original scientific article Abstract: In this paper, a comparative analysis of the effects of groundwater, seepage and hydraulic heave on the optimal design of embedded retaining walls is carried out. The optimization model for an optimal retaining wall (ORW) minimizes the total length of the retaining wall considering design constraints. The model is extended to include the probability of failure as an additional constraint. This overcomes the limitations of the partial safety factor approach, which does not fully account for uncertainties in the soil. In contrast, the reliability-based design (RBD) approach integrates these uncertainties and enables an assessment of the impact of seepage and hydraulic heave on the reliability of the structure. A real-coded genetic algorithm was used to determine optimal designs for both optimization methods. The results of the case study show that the addition of seepage (groundwater flow) to the hydrostatic conditions has a modest effect on the embedment depth. The design based on partial safety factors, which takes seepage into account, leads to a slight increase in the embedment depth of 0.94% compared to a retaining wall design that only takes the hydrostatic conditions of the groundwater into account. When designing on the basis of probability failure, the percentage increase in embedment depth due to seepage is between 2.19% and 6.41%, depending on the target probability of failure. Furthermore, the hydraulic heave failure mechanism did not increase the required embedment depth of the retaining wall, which means that the failure mechanism of rotation near the base was decisive for the design.
Keywords: embedded retaining wall, reliability-based design, partial safety factor design, optimization, genetic algorithm
Published in DKUM: 10.12.2024; Views: 0; Downloads: 13
Full text (2,13 MB)
This document has many files! More... |
6. Advanced Quantitative Research Methods in NursingLucija Gosak, Leona Cilar Budler, Roger Watson, Gregor Štiglic, 2024 Abstract: The publication "Analysis of quantitative research data in nursing research: A guide to SPSS" provides nursing students and nurses with the knowledge and skills to interpret the different statistical methods in their field, which can improve users' skills in collecting, analysing and interpreting results from clinical practice, thus contributing to improving the quality of health care. It provides detailed instructions on how to use IBM SPSS and perform statistical analyses that nurses need to be familiar with as they use and generate data in their daily work with patients. The main aim of patient care is to provide high quality, evidence-based care, so nurses have a duty to keep up to date with the latest research and evidence and apply it to their work. The knowledge gained in this book can also help nurses to better understand and interpret previously published results, and thus critically assess the validity and reliability of the results they will use in clinical practice.
Keywords: quantitative analysis, statistics, IBM SPSS, reliability, validity, data analysis
Published in DKUM: 18.07.2024; Views: 113; Downloads: 27
Full text (18,18 MB)
This document has many files! More... |
7. Peak torque comparison between SMM iMoment in Biodex System Pro 4 isokinetic dynamometersMatjaž Vogrin, Teja Ličen, Nina Greiner, Miloš Kalc, 2020, original scientific article Keywords: inter-machine reliability, knee extensors, knee flexors, angle of peak torque, peak torque
Published in DKUM: 23.01.2023; Views: 650; Downloads: 16
Full text (1,43 MB)
This document has many files! More...
This document is also a collection of 1 document! |
8. How to test the reliability of instruments used in mirotremor horizontal-to-vertical spectral ratio measurementsIzidor Tasič, Franc Runovc, 2010, original scientific article Abstract: The reliability of a horizontal-to-vertical spectral ratio (HVSR) curve depends on the results obtained by a verified seismological system. Seismic microzonation provides the basis for a site-specific risk analysis and it can be evaluated using the microtremor HVSR method, where the data are recorded using modern seismological systems. Changes in the transfer function of seismological systems affect the HVSR curve and, consequently, also its interpretation, if these changes are not detected and taken into consideration while performing the microtremor spectral calculations. The reliability of the seismic microzonation performed by such a procedure becomes questionable. An algorithm is developed with a two references system, where the influence of the transfer function on the HVSR curve by the tested system can be evaluated without any a-priori knowledge regarding the transfer functions of any of the systems. This approach is applied to a Lennartz Le-3D/5s seismometer and to a TROMINO seismological system, where two Streckeisen STS2 seismometers are used as the reference systems.
Keywords: seismic microzonation, horizontal-to-vertical spectral ratio method, ambient vibrations, microtremor, seismic system transfer function, reliability and calibration of seismic systems
Published in DKUM: 11.06.2018; Views: 1139; Downloads: 67
Full text (201,91 KB)
This document has many files! More... |
9. Validation test plan for relays in avtomotive industryUrban Cotič, 2017, master's thesis Abstract: The master’s thesis discusses different approaches how to assure the quality and reliability of high voltage contactors in automotive industry. In the beginning, the history of the development is described, followed by basic knowledge about materials and magnetic theory used in relays. The main part of the thesis is tests defying to qualify the relays for usage in automotive industry. There are different tests, divided in different groups. Second important part is reliability prediction according to standards used in this area of business. Reliability prediction and calculation of failure rate on different contactors are described in last chapters. Calculation also included influence of different factors on life span of the parts. In conclusion, the results are commented and proposal for development is given based on results of the research.
Keywords: Automotive industry, high voltage contactors, testing, reliability, failure rate
Published in DKUM: 07.02.2018; Views: 1592; Downloads: 133
Full text (1,89 MB) |
10. Weibull decision support systems in maintenanceKhalid Aboura, Johnson Agbinya, Ali Eskandarian, 2014, original scientific article Abstract: Background: The Weibull distribution is one of the most important lifetime distributions in applied statistics. Weibull analysis is the leading method in the world for fitting and analyzing lifetime data. We discuss one of the earliest decision support system for the assessment of a distribution for the parameters of the Weibull reliability model using expert information. We then present a different approach to assess the parameters distribution.
Objectives: The studies mentioned in this paper aimed to construct a distribution of the parameters of the Weibull reliability model and apply it in the domain of Maintenance Optimization.
Method: The parameters of the Weibull reliability model are considered random variables and a distribution for the parameters is assessed using informed judgment in the form of reliability estimates from vendor information, engineering knowledge or experience in the field.
Results: The results are the development of modern maintenance optimization models that can be embodied in decision support systems.
Conclusion: While the information management part is important in the building of maintenance optimization decision systems, the accuracy of the mathematical and statistical algorithms determines the level of success of the maintenance solution.
Keywords: Weibull distribution, reliability, inference, maintenance, expert opinion
Published in DKUM: 23.01.2018; Views: 2221; Downloads: 357
Full text (527,86 KB)
This document has many files! More... |
