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Assessing the Performance of Machine Learning Algorithms for Soil Classification Using Cone Penetration Test Data

Ayele Chala R. P. Ray

Publication Name: Applied Sciences Switzerland

Publication Date: 2023-05-01

Volume: 13

Issue: 9

Page Range: Unknown

Description:

Conventional soil classification methods are expensive and demand extensive field and laboratory work. This research evaluates the efficiency of various machine learning (ML) algorithms in classifying soils based on Robertson’s soil behavioral types. This study employs 4 ML algorithms, including artificial neural network (ANN), random forest (RF), support vector machine (SVM), and decision trees (DT), to classify soils from 232 cone penetration test (CPT) datasets. The datasets were randomly split into training and testing datasets to train and test the ML models. Metrics such as overall accuracy, sensitivity, precision, F1_score, and confusion matrices provided quantitative evaluations of each model. Our analysis showed that all the ML models accurately classified most soils. The SVM model achieved the highest accuracy of 99.84%, while the ANN model achieved an overall accuracy of 98.82%. The RF and DT models achieved overall accuracy scores of 99.23% and 95.67%, respectively. Additionally, most of the evaluation metrics indicated high scores, demonstrating that the ML models performed well. The SVM and RF models exhibited outstanding performance on both majority and minority soil classes, while the ANN model achieved lower sensitivity and F1_score for minority soil class. Based on these results, we conclude that the SVM and RF algorithms can be integrated into software programs for rapid and accurate soil classification.

Open Access: Yes

DOI: 10.3390/app13095758

STRESS ANALYSIS OF PRESSING JOINT OF TWO CONICAL PIPES

Roland Jančo

Publication Name: Strojnicky Casopis Journal of Mechanical Engineering

Publication Date: 2023-05-01

Volume: 73

Issue: 1

Page Range: 117-124

Description:

This paper presents a stress analysis of a pressed joint of two conical pipes with the aim to find out whether this kind of connection is suitable for telecommunication masts. The analysis can be considered a complex spatial problem of a thin-walled shell, where the local bending stress influence might be dominant. In this paper a solution using engineering approach and numerical analysis with finite element method (FEM) will be compared.

Open Access: Yes

DOI: 10.2478/scjme-2023-0009

Thematic Analysis Of Google Play Reviews Of Lifestyle Apps

Ida Ercsey Veronika Keller

Publication Name: Human Technology

Publication Date: 2023-05-01

Volume: 19

Issue: 1

Page Range: 82-102

Description:

Worldwide, numerous studies have been conducted on m-health applications and the results show that, if well-designed, they can regulate and track medication and reduce healthcare costs. The aim of this research is to analyze the experiences of users connected to different lifestyle apps, in particular (1) to explore the negative, neutral and positive topics in the reviews, and (2) to discover the role of health improvement among the comments. The present paper is part of a complex empirical research project. A qualitative and quantitative content analysis was conducted of the user reviews in the Google Play store for the 16 lifestyle apps selected during the first phase of the empirical research (quasi experiment). All in all, 2,835 comments were analyzed. The negative comments mentioned unreliable tracking functions, problems with updates, or high prices. The neutral comments outlined some missing functions or problems with the operation of the app. The positive comments were related to health improvement, usefulness, ease of use, engagement and willingness to recommend the app. Physical activity, facilitating a specific diet, weight loss, wellbeing, tracking progress and health awareness were among the common health aspects of the lifestyle apps. The results of this research will be particularly useful for consumers, app developers and service providers who focus on health awareness and health promotion.

Open Access: Yes

DOI: 10.14254/1795-6889.2023.19-1.6

Water Use Efficiency and Productivity of Irrigated Rice Cultivation in Nigeria: An Application of the Stochastic Frontier Approach

Khalid Mushtaq Laszlo Vasa Magdalena Radulescu Asghar Ali Sajjad Ahmad Baig Piotr Prus Abdulazeez Hudu Wudil Muhammad Usman

Publication Name: Sustainability Switzerland

Publication Date: 2023-05-01

Volume: 15

Issue: 10

Page Range: Unknown

Description:

In the face of declining water resources and low agricultural water productivity, it is vital to increase agricultural production efficiency and efficiency of water usage. The efficacy of irrigating rice fields in Nigeria is evaluated here using a stochastic frontier analysis. This is a parametric frontier that is assumed to have half-normal distribution, allowing the model to be separated from normal errors in a composite error model. Samples of 382 surveys were used in the study; out of the total number, 361 surveys were retrieved and used for the analysis. The analytical tools used in the study are: gross margin, water productivity analysis, and stochastic frontier approach. The results indicate an average yield of 4.69 and 4.94 tons/hectare, and net farm income of $415 and $364 for the farmers using canal irrigation and farmers using tube wells, respectively. The results also showed physical and economic water productivity of 0.51 kg/m3 and $0.11/m3 for canal water users, and 0.568 kg/m3 and $0.10/m3 for tube well users. The canal water users had a mean irrigation water use efficiency of 0.76, compared to 0.70 for the tube well users. The study recommends that effective extension services and their coverage be enhanced to provide adequate training to rice farmers on water use efficiency and the transfer of innovations and farming technologies to farmers.

Open Access: Yes

DOI: 10.3390/su15107824

Military Assistance to Ukraine and Its Significance in the Russo-Ukrainian War

Kolos Kusica Julia Szoke

Publication Name: Social Sciences

Publication Date: 2023-05-01

Volume: 12

Issue: 5

Page Range: Unknown

Description:

The interest of social sciences in the military dates back ages, and currently, special attention is being paid to Russia’s war in Ukraine. The present paper also follows this research trend, and it intends to analyze both the tactical and operational levels of war by investigating how the military assistance provided by Western states and international organizations to Ukraine is influencing the course of the Russo-Ukrainian war. Subsequently, the paper studies the military assistance in all three phases of the war, beginning from the invasion of Crimea, through the Donbas offensive, to the phase of Ukrainian counter-offensives. The research method used by this paper was to review and synthesize the existing but scarce and sometimes disinformative literature. The findings suggest that Western military aid began cautiously by providing only non-lethal, defensive weapons, but it was of crucial importance in the second phase of the war by guaranteeing heavy weaponry. The paper concludes that Western military assistance, especially from the United States, United Kingdom, Poland, and Germany, has had a significant role in the Russo-Ukrainian war, without which Ukrainian forces may not have persisted to now.

Open Access: Yes

DOI: 10.3390/socsci12050294

Evaluation of the Szapáry Long-Span Box Girder Bridge Using Static and Dynamic Load Tests

Rajmund Kuti M. Brinissat R. P. Ray

Publication Name: Infrastructures

Publication Date: 2023-05-01

Volume: 8

Issue: 5

Page Range: Unknown

Description:

This paper presents the results of a recent field test carried out before the opening phases of the Szapáry motorway bridge across the Tisza River in central Hungary. The evaluation test was based on static and dynamic load tests that provided information on deflection, stresses, and dynamic mode shapes along the bridge. The structure has two large continuous independent steel box girders that cover spans across the floodplain and river. Various configurations of truck loading applied up to 6400 kN of loading on the deck. During the static tests, string potentiometers recorded deflections at mid-span. Additionally, strain gauges enabled strain/stress measurements at the mid-point of the longest span and directly above one support. Dynamic loadings showed variation in deflection response due to vehicle speed, and ambient vibration testing led to determining vibration modes and frequencies. A three-dimensional finite-element model produced similar deflections, stresses, and modal behavior. Measured and modeled deflections and stresses indicated that the bridge performed within design margins. The testing and analysis results will be part of a future program assessing conditioned-based maintenance.

Open Access: Yes

DOI: 10.3390/infrastructures8050091

Elicitation of Content Layout Preferences in Virtual 3D Spaces Based on a Free Layout Creation Task

Adam Csapo Anna Sudar

Publication Name: Electronics Switzerland

Publication Date: 2023-05-01

Volume: 12

Issue: 9

Page Range: Unknown

Description:

Three-dimensional virtual reality (VR) environments, whether operating on desktop platforms or immersive screens, have been recognized for enabling novel and extremely engaging methods of interacting with digital content across various fields of application. Studies conducted over the past several years have also consistently suggested that utilizing 3D in contrast to 2D interfaces can lead to enhancements in multiple performance dimensions. These enhancements encompass better understanding and retention of information, increased capacity for inventive and efficient collaboration, and the ability to execute workflows that integrate numerous information sources more quickly. At the same time, how digital content such as documents, audio–visual content and web browsers are integrated into 3D spaces is often decided by the creators of the spaces based on either aesthetic considerations, or on a case-by-case basis depending on the workflow. In this paper, we present the results of an experiment we conducted to better understand how users prefer to arrange digital content in their 3D environments, depending on the subject matter, the format of the content (e.g., text-based, image, or audio–visual) and the 3D objects within the space. The results of the experiment presented in the paper can help inform future 3D VR design methodologies and may also provide support for automated content arrangement solutions.

Open Access: Yes

DOI: 10.3390/electronics12092078

Two-Dimensional Numerical Analysis for TBM Tunneling-Induced Structure Settlement: A Proposed Modeling Method and Parametric Study

Rashad Alsirawan Ammar N. Alnmr Ashraf Sheble

Publication Name: Infrastructures

Publication Date: 2023-05-01

Volume: 8

Issue: 5

Page Range: Unknown

Description:

The construction of tunnels in densely populated urban areas poses a significant challenge in terms of anticipating the settlement that may result from tunnel excavation. This paper presents a new and more realistic modeling method for tunnel excavation using a Tunnel Boring Machine (TBM). This method is compared with other reference modeling methods using a validated model of a subsurface tunnel excavated by a TBM with a slurry shield. A parametric study is conducted to investigate the impact of key parameters, including structure width, foundation depth, eccentricity, load on the structure, overburden depth, and tunnel diameter, on tunnel–soil–structure interaction and the resulting structure settlements. The results reveal that the tunnel diameter, eccentricity, and overburden depth have a significant impact on structure settlements, with values of 22.5%, 17%, and 7.1%, respectively. Finally, the paper proposes an equation for predicting the maximum settlement of a structure, considering the critical parameters. The validity of the equation is evaluated by comparing its results with the outputs from various case studies, including a newly validated model, two real-life case studies, and centrifuge tests. The results indicate a high level of consistency between the calculated and measured settlements.

Open Access: Yes

DOI: 10.3390/infrastructures8050088

New Organizational Environment Types Based on Garvin and Quinn – the Case of Slovakian Small and Medium Enterprises

Ladislav Mura Tibor Zsigmond Ferenc Bakó Marcell Kupi

Publication Name: TEM Journal

Publication Date: 2023-05-01

Volume: 12

Issue: 2

Page Range: 691-699

Description:

The aim of the study was to examine what common characteristics can be observed in companies based on Garvin’s learning organization and the Quinn’s organizational culture. Both of the trends are considered a fundamental factor of modern management. Studying the international scientific literature, it is clear that examining the overlaps between the two approaches is highly incomplete. The issue was approached from the perspective of employees, as they show high willingness to express their opinion. A questionnaire survey was used as a part of our research. 549 responses were included in the analysis, during which we applied a cluster analysis. Based on the results, three different types of organizational environment can be defined: supporting, neutral and distancing.

Open Access: Yes

DOI: 10.18421/TEM122-12