Testing Techniques Research Articles

Combinatorial transition testing in dynamically adaptive systems: Implementation and test oracle

Due to the large number of possible interactions and transitions among features in dynamically adaptive systems, testing such systems poses significant challenges. To verify that such systems behave correctly, combinatorial interaction testing (CIT) can create concise test suites covering all valid pairs of features of such systems. While CIT claims to find all errors caused by two features, it does not cover certain errors occurring only for specific transitions between features. To address this issue we study the technique of Combinatorial Transition Testing (CTT), which includes both generation and detection of what we call behavioural transition errors. From an initial generation algorithm that combines both interaction and transition coverage but lacks scalability, we propose an optimised version that enables CTT even for hundreds of features. From a valid test suite covering all transitions, we complete our testing approach with a test oracle that detects all behavioural transition errors without any prior knowledge of the system’s behaviour. After a comprehensive analysis over a large number of feature models, we conclude that size of CTT-generated test suites and test effort needed to use our test oracle are linearly correlated to CIT-generated ones and that CTT grows logarithmically in the number of features.

Wall thinning quantification with a lift-off distance for ferromagnetic structures using pulsed ECT equipped with ICA-Gauss filter and Hough Transform

Determining the thickness of ferromagnetic materials with a lift-off distance poses a significant challenge for current non-destructive testing (NDT) techniques. Pulsed eddy current (PEC) testing is deemed as a powerful candidate to evaluate this type of defect. However, the signal-to-noise ratio (SNR) of the PEC response signal obtained with large lift-off distance is very poor, so that the signal feature can hardly be extracted. To improve the SNR of PEC response signals and capture the signal feature adaptively, this paper proposed a novel PEC signal processing algorithm based on ICA-Gauss filter and Hough Transform (HT). Firstly, the principle of the proposed method was introduced. Then, two case studies, a comparison experiment and an application experiment were conducted to verify the effectiveness and accuracy of this method. Results from these experiments show that (a) the ICA-Gauss filter can effectively suppress the power-line noises and random noises in PEC signals, (b) the ICA-Gauss filter outperforms traditional filters in feature robustness and computing efficiency, including double-logarithmic median filter and Savitzky-Golay filter, and (c) HT is an adaptive and accurate method to extract the PEC signal feature, thus achieving a small detection error.

K, Sr isotopes, and trace element to constrain potash origin in the Simao Basin, southwestern China, and insight into K isotope geochemical behavior in evaporite

With the advancement of emerging potassium isotope testing techniques, the characteristics of δ41K in evaporite have garnered increasing attention. Its application in constraining the genesis of potash deposits and tracing the process of potash mineralization holds significant prospects. A comprehensive analysis of the geochemical characteristics of K, Sr isotopes, and trace elements provides an opportunity to address the ongoing debate regarding the mineralization mechanism of potash in the Simao Basin. In this study, we collected 64 potash samples from the Simao and Khorat basins. The analytical results revealed that the major ions in the samples consist of Na+, K+, Mg2+, Ca2+, Cl−, and SO2- 4, while the trace elements Br, Sr, Rb, B, Li, V, Cr, Mn, Ba, As, and Zn are relatively enriched. The δ41K values range from − 0.12 ‰ to 0.20 ‰ with an average of 0.01 ‰. The 87Sr/86Sr ratios range from 0.707553 to 0.708565 with an average of 0.708020, which is lower than that of the river water in the drainage basin. Additionally, the Br content ranges from 316.3 × 10−6 to 1709.1 × 10−6, with an average of 633.8 × 10−6. These data indicate that the Early Cretaceous Albian-Middle Jurassic Bajocian seawater serves as an important source of potassium for potash deposition in the Simao Basin. The characteristics of the ratios of the Br/Cl (mmol/mol), K/Cl (mmol/mol), Rb/Sr (mol/mol), along with the contents of the Br and Rb, indicate that the most of potash in the Simao Basin is primary origin. Moreover, we have also provided new insight into the geochemical behaviors of K isotopes during the evolution of the evaporites. The precipitation of potash may be accompanied by K isotope fractionation, as evidenced by the lighter K isotope composition of carnallite compared to that of sylvinite. K isotope fractionation occurs between the secondary sylvite and its parent source, and newly precipitated solids are characterized by relatively light K isotope Episodic freshwater inflow into the evaporative basin stimulates microbial activity, leading to fluctuations in K isotopes in the precipitated potash during the same evaporation stage. Therefore, this work not only provided direct evidence from the K isotopes for determining the origin of the potash in the Simao Basin but also further perceived the geochemical behaviors of K isotopes during the evolution of evaporite.

Serological Markers of Clinical Improvement in MuSK Myasthenia Gravis.

In this retrospective longitudinal study, we aimed at exploring the role of (a) MuSK-immunoglobulin G (IgG) levels, (b) predominant MuSK-IgG subclasses, and (c) antibody affinity as candidate biomarkers of severity and outcomes in MuSK-MG, using and comparing different antibody testing techniques. Total MuSK-IgGs were quantified with radioimmunoassay (RIA), ELISA, flow cytometry, and cell-based assay (CBA) serial dilutions using HEK293 cells transfected with MuSK-eGFP. MuSK-IgG subclasses were measured by flow cytometry. SAffCon assay was used for determining MuSK-IgG affinity. Forty-three serum samples were obtained at different time points from 20 patients with MuSK-MG (median age at onset: 48 years, interquartile range = 27.5-72.5; women, 16/20), with 9 of 20 (45%) treated with rituximab. A strong correlation between MuSK-IgG levels measured by flow cytometry and RIA titers was found (rs = 0.74, 95% CI 0.41-0.89, p = 0.0003), as well as a moderate correlation between CBA end-point titers and RIA titers (rs = 0.47, 95% CI 0.01-0.77, p = 0.0414). A significant correlation was found between MuSK-IgG flow cytometry levels and disease severity (rs = 0.39, 95% CI 0.06-0.64, p = 0.0175; mixed-effects model estimate: 2.296e-06, std. error: 1.024e-06, t = 2.243, p = 0.032). In individual patients, clinical improvement was associated with decrease in MuSK-IgG levels, as measured by either flow cytometry or CBA end-point titration. In all samples, MuSK-IgG4 was the most frequent isotype (mean ± SD: 90.95% ± 13.89). A significant reduction of MuSK-IgG4 and, to a lesser extent, of MuSK-IgG2, was seen in patients with favorable clinical outcomes. A similar trend was confirmed in the subgroup of rituximab-treated patients. In a single patient, MuSK-IgG affinity increased during symptom exacerbation (KD values: 62 nM vs 0.6 nM) while total MuSK-IgG and IgG4 levels remained stable, suggesting that affinity maturation may be a driver of clinical worsening. Our data support the quantification of MuSK antibodies by flow cytometry. Through a multimodal investigational approach, we showed that total MuSK-IgG levels, MuSK-IgG4 and MuSK-IgG2 levels, and MuSK-IgG affinity may represent promising biomarkers of disease outcomes in MuSK-MG.

Study on the hydration characteristics and mechanical properties of recycled powder-slag powder-cement system

This study systematically investigated the influence of different blending ratios of recycled powder and slag powder on hydration heat evolution and mechanical properties. Various modern microscopic testing techniques were employed to quantitatively characterize hydration products and microstructures, revealing their hydration mechanisms. The results indicate that both recycled powder and slag powder can accelerate the early hydration rate. When recycled powder and slag powder are co-blended, their early hydration rate and cumulative heat release surpass those of specimens with single additions of recycled powder. Moreover, the mechanical properties in the later stage are superior to those of specimens with single additions of recycled powder. At 60d, the PRS70-1-2 in the multi doped recycled powder and slag powder system even exceeds that of the uni doped SL system, but is much higher than that of the uni doped RP system，the compressive strength of the multi doped recycled powder and slag powder system increased by 25.5%, 37.1% and 36.9%, respectively, compared with that of the uni doped RP system. Specimens with single additions of recycled powder and slag powder have a relatively high proportion of harmful and very harmful pores. At 28d, the porosity of the multi doped recycled powder and slag powder system decreased by 19.2%, 24.2% and 14.8%, respectively, compared with that of the uni doped RP system. However, when recycled powder and slag powder are co-blended, the proportion of harmful and very harmful pores decreases, while the proportion of less harmful and harmless pores increases. This leads to an overall reduction in porosity and an improvement in mechanical properties.

Integrasi Penilaian Tes dan Non-Tes dalam Pendidikan Agama Islam: Menuju Evaluasi Holistik untuk Pembelajaran Berkelanjutan

This study discusses the development and implementation of an assessment model for Islamic Education (PAI) that integrates both test and non-test techniques. The study is conducted through a comprehensive literature review encompassing various academic sources related to PAI assessment. The findings reveal that test techniques, such as multiple-choice questions and essays, are highly effective in assessing students' cognitive understanding of Islamic concepts. However, these techniques have limitations in evaluating the affective and psychomotor domains, which are also crucial in shaping students' character. On the other hand, non-test techniques, including observations, portfolios, and projects, are better suited for assessing affective and psychomotor aspects, providing a more holistic view of students' development. The combination of test and non-test techniques allows for a more comprehensive, fair, and holistic evaluation of all aspects of student learning, encompassing knowledge, attitudes, and skills. The implications of this study emphasize the importance of a holistic assessment approach in Islamic education, as well as the need for teacher training in the application of non-test techniques to ensure objectivity and validity in assessments. Thus, this research makes a significant contribution to improving the quality of Islamic education through assessments that are more adaptive, responsive, and relevant to students' needs in the modern era

Problem-based blended learning: The student’s critical thinking skills in the respiratory system material

Critical thinking skills should be integrated into high school biology education through problem-based blended learning.. This study aims to determine the effect of the Problem-Based blended learning model on students' critical thinking skills in the material on the respiratory system at SMA A. This quasi-experimental study used a nonrandomized control group, pretest-posttest design involving 2 XI classes, namely the control class, which consisted of 33 students and 32 students in the experimental class. Collecting data on critical thinking skills is using a test technique. The test instrument used is a question sheet (pretest and posttest). The data analysis consisted of analysis prerequisites in the form of a normality test and homogeneity test, as well as hypothesis testing in the form of the Mann-Whitney test. This study's results indicate a significant influence on students' critical thinking skills in the respiratory system material for class XI at SMA A after applying the Problem-Based blended learning model assisted by Google Classroom. This can be seen from the average test of critical thinking skills in the experimental class, which is higher than the control class.

Website-Based Learning Media Using Google Sites to Improve Student Learning Outcomes in Natural and Social Sciences Subjects on Biodiversity Material

Inappropriate use of learning media in learning process activities can cause uninteresting learning. This study aims to develop website-based learning media using Google Sites in the Natural and social sciences subject biodiversity material in grade V elementary school. The research method used is Research and Development with the ADDIE development model. The subjects in this study were media experts, material, teachers, and 21 fifth-grade elementary school students. Data collection is used in the form of test techniques and non-test techniques. The test techniques used are pretest and posttest, while non-test techniques include observation, interviews, questionnaires, and documentation. In the data analysis process, the normality test, t-test, and N-Gain test methods were used, which were carried out with SPSS 23 software. The results of the study presented a validation test by media experts getting a score of 91%, while the validation test by material experts got a score of 92%, with a very feasible category. The t-test results on the small group trial presented a sig. (2-tailed) of 0.008. while in the large group trial, the t-test presents a sig value (2-tailed) of 0.000. The results of the N-Gain Test in the small group and large group trials showed an increase in value of 0.60 and 0.55 which was in the medium category. This shows an average increase between pretest and posttest scores. From these results, it is concluded that website-based learning media using Google Sites is very feasible and effective in improving student learning outcomes related to the biodiversity material in grade V elementary school.

KEMAMPUAN MEMBACA PERMULAAN AKSARA LONTARAK SISWA KELAS III SDN NO. 204 INPRES BALANG KABUPATEN TAKALAR

The aim of this research is to describe the initial reading ability of the lontarak script of class III students at SDN NO. 204 Balang Presidential Instruction, Takalar Regency. This type of research is quantitative research in the form of quantitative descriptive. The population in this study were all class III students at SDN NO. 204 Inpres Balang, totaling 19 people, is only in 1 class. The sample determined was 19 students, using a saturated sampling technique. The data collection technique used is a test technique, namely an oral test. The data collected will be analyzed using descriptive statistical techniques. The results showed that the ability to read the beginning of the lontarak script of class III students at SDN No. 204 Balang Presidential Instruction Takalar Regency is declared incapable. This can be seen from the percentage of students who obtained a score ≥ 75 in the capable category that did not reach the set criteria, namely 75%, but only achieved 42.1%.

Incidence of Pathogens in Fruits and Vegetables in Tropical Bwari Town

Introduction: In numerous tropical regions of developing nations, the prevalence of foodborne illnesses is perceived to be more severe than in developed countries, due to insufficient food safety initiatives or the lack of a structured institutional framework for street food vendors. The study's objectives of examining microorganisms associated with fruits and vegetables, the prevailing temperature and the hygiene practices of various fruit and vegetable sellers were all met. Methods: A self-designed questionnaire completed by twenty vendors were used. Laboratory techniques like serial dilution, biochemical testing, and culture techniques were used. A handheld thermometer was used to determine the prevailing temperature, and descriptive statistics using Microsoft Excel was used to analyze data. Results and Discussion: Statistical analysis revealed that 80% of vendors had washing facilities, 70% worked in a clean environment, 20% washed their hands before handling fruits, 70% dressed correctly, and 70% kept their fruits and vegetables above the WHO temperature standard. A laboratory investigation revealed the bacteria counts of (watermelon being the highest 8.3×105, cucumber 5.4×105, carrot 2.3×105, orange 3.7×105). Microbial species encountered were Staphylococcus aureus, Escherichia coli, Salmonella species, amongst others, which increases health risk. Conclusion: The study concluded that temperatures, handling processes, and inadequate hygiene all had impact on fruits and vegetables sold in tropical Bwari area. It also established a link between temperature and the prevalence of bacteria in fruits and vegetables. As a result, the study suggests monitoring and surveillance of fruit and vegetable sellers, national vendor hygiene policies and public awareness.

KEMAMPUAN MEMBACA NYARING TEKS CERITA BUGIS SISWA KELAS V SDN 85 WANUA BARU KABUPATEN MAROS

This research is a descriptive quantitative study that aims to describe the ability to read aloud Bugis story texts of fifth grade students of SDN 85 Wanua Baru, Maros Regency. The population of this study were all fifth grade students of SDN 85 Wanua Baru, Maros Regency in the 2023/2024 school year, totaling 15 students. The withdrawal of samples in this study was carried out by means of total sampling because the population was less than one hundred. The data collection techniques used in this study were oral test techniques and recording techniques. The data obtained were analyzed using quantitative descriptive analysis. There are four aspects of assessment used in this study, namely aspects of fluency, aspects of the use of intonation, aspects of pronunciation, and aspects of voice volume. Based on the results of the data analysis obtained, it shows that the ability to read aloud Bugis story text of fifth grade students of SDN 85 Wanua Baru Maros Regency, namely (1) the fluency aspect of students who scored above 70, namely 10 people with a percentage of 60% declared unable, (2) the aspect of using intonation of students who scored above 70, namely 8 people with a percentage of 53% declared unable, (3) the aspect of pronunciation of students who scored above 70, namely 3 people with a percentage of 20% declared unable, and (4) the aspect of voice volume of students who scored above 70, namely 12 people with a percentage of 80% declared able

Implementasi Game Interaktif Kahoot dalam Meningkatkan Literasi Siswa Kelas 2 SD

This research aims to determine the use of the Kahoot application in improving the literacy of second grade elementary school students. This research is classroom action research. Data collection was carried out using test and non-test techniques. Test techniques include tests at the end of cycle I and end of cycle II and non-tests include observing student activities and comparing the results of observations and tests. The data analysis technique uses qualitative descriptive. The PTK design applied uses the Kemmis and Mc Taggart (1998) model. The results of this research are that the Kahoot application is very helpful in increasing elementary school students' literacy very significantly. This is because the Kahoot application is an application that is used as a very innovative and interesting learning media technology, especially for elementary school students who are unfamiliar with digital devices.

THE EFFECT OF TRAINING AND MOTIVATION ON EMPLOYEE PERFORMANCE AT PT MUTIARA SAMUDERA PASAI

The purpose of this study was to determine the effect of Training and Motivation on the Performance of PT. Mutiara Samudera Pasai employees. The method used in this study is a quantitative method, with analysis techniques of validity testing, reliability testing, classical assumption testing, simple and multiple linear regression testing. The sample used was 60 respondents, namely the entire population. The results of this study are: 1) There is a positive and significant influence of the Training (X1) and Motivation (X2) variables on Performance (Y) of 39.1%, obtained an R number (correlation coefficient) of 0.625. 2) There is a positive and significant influence of the Training (X1) and Motivation (X2) variables on Performance (Y) of 55.5%, obtained an R number (correlation coefficient) of 0.745. 3) There is a positive and significant influence of the variables Training (X1) and Motivation (X2) together on Performance (Y of 55.9%, obtained the R number (correlation coefficient) of 0.748. Suggestions in this study are expected that the Leader can increase Motivation so that employees can increase work productivity so that it can be more optimal, Management can improve the economic welfare of employees, Leaders are more careful in determining the type of training and training methods that have an impact on improving employee abilities

Assessing University Final Examination Questions Written in English

Test is regarded as a tool to measure the outcome of teaching and learning processes. There are other tools, but tests are still used to a great extent. The objective of the current study is to assess university final examination questions written in English, and College of Education-Shaqlawa has been selected as a sample. The test papers have been received from the Examination Committee of the college. Tests have several properties, but only three properties, namely accuracy, objectivity and scorability, have been chosen to be the criteria of the research. This is because the selected characteristics are general, while the left ones are specific to particular subjects. The procedure of the study is descriptive and analysis. The test papers have been analysed twice for reliability. The researchers have benefited from other researchers’ criteria. It has been detected that the test papers are objective to great extent. This is due to the test techniques that are used by the instructors. Unfortunately, some test papers have been found to be inaccurate. Inaccuracy has resulted from many areas such as grammatical mistakes and punctuation marks. Little attention has been given to the field of punctuation marks. Furthermore, some test papers have been detected to seem strange in terms of scorability. To clarify it, the mark distribution and the total mark of some test papers are not in agreement with the requirements. Finally, the conclusions, suggestions and references have been shown.

LiDAR-Based Unmanned Aerial Vehicle Offshore Wind Blade Inspection and Modeling

The deployment of offshore wind turbines (WTs) has emerged as a pivotal strategy in the transition to renewable energy, offering significant potential for clean electricity generation. However, these structures’ operation and maintenance (O&M) present unique challenges due to their remote locations and harsh marine environments. For these reasons, it is fundamental to promote the development of autonomous solutions to monitor the health condition of the construction parts, preventing structural damage and accidents. This paper explores the application of Unmanned Aerial Vehicles (UAVs) in the inspection and maintenance of offshore wind turbines, introducing a new strategy for autonomous wind turbine inspection and a simulation environment for testing and training autonomous inspection techniques under a more realistic offshore scenario. Instead of relying on visual information to detect the WT parts during the inspection, this method proposes a three-dimensional (3D) light detection and ranging (LiDAR) method that estimates the wind turbine pose (position, orientation, and blade configuration) and autonomously controls the UAV for a close inspection maneuver. The first tests were carried out mainly in a simulation framework, combining different WT poses, including different orientations, blade positions, and wind turbine movements, and finally, a mixed reality test, where a real vehicle performed a full inspection of a virtual wind turbine.

Epidemiology and prognosis of obstructive and non-obstructive hypertrophic cardiomyopathy in Finland: a nationwide cohort study

Abstract Background Hypertrophic cardiomyopathy (HCM) is an often hereditary myocardial disease. The Finnish population has a specific genetic background, which may influence and even predispose people to various hereditary diseases. Whilst advances in genetic testing and imaging techniques may have influenced the detection of HCM and associated subtypes, contemporary data on incidence and prevalence remain limited. Purpose This study aimed to evaluate the current trends in the incidence, prevalence, and prognosis of obstructive and non-obstructive HCM in a nationwide cohort in Finland. Methods A population-based registry study was conducted using data from Finnish nationwide healthcare registries (HILMO/avoHILMO) including individuals aged at least 12 years with recorded HCM diagnosis between 2000 and 2021. The incidence was calculated by dividing the number of newly diagnosed HCM patients by the Finnish background population. Furthermore, the mean incidence per age-group was calculated by dividing the sum of age-group specific incidences by the number of age groups. The date and cause of death were obtained from national registries (Statistics Finland). Mortality was computed by dividing the number of deaths by follow-up length. Patients were followed from 2014 to 2021, and incident cases were defined as new diagnoses after 2014. HCM cases were stratified into obstructive HCM and non-obstructive HCM based on ICD-10 codes I42.1 and I42.2, respectively. Results Among 5,834 documented patients with HCM, the overall mean incidence by age-group was 2.64/100,000, with incidence increasing with age, peaking in those aged ≥85 years (6.22/100,000 patient-years [PY]). Annual incidence of obstructive HCM decreased from 2.2 to 1.4/100,000 PY, while non-obstructive HCM increased from 4.6 to 5.4/100,000 PY between 2014 and 2021 (Fig 1). Prevalence of non-obstructive HCM rose from 40 to 56/100,000 PY, while obstructive HCM prevalence remained stable (23-24/100,000 PY). All-cause mortality was 5.5/100 PY, with obstructive and non-obstructive HCM mortality at 5.7 and 4.6/100 PY, respectively. HCM-specific deaths accounted for 16% and 12% of all deaths in patients with non-obstructive and obstructive HCM, respectively. Conclusions This nationwide study in Finland revealed an increasing incidence and prevalence of non-obstructive HCM over time, contrasting with stable rates among patients with obstructive HCM. Incidence and prevalence were strongly age dependent. Non-HCM-related deaths were predominant in both HCM subtypes.

MACRO-ECONOMETRIC ANALYSIS OF INWARD CAPITAL FLOWS: A CASE OF NIGERIA IN TIMES OF SECURITY CHALLENGES

This study used quarterly data for the period of 2014Q1–2021Q2 to investigate the macro-econometric implications of capital flows to Nigeria in the face of security challenges. The ARDL bounds test technique identified the long-run relationships between macroeconomic dynamics, insecurity, and total capital inflows to Nigeria, while the error correction mechanism (ECM) identified the short-run relationships. The Toda-Yamamoto test was used to determine whether the model variables were causally related or not. The findings pointed to a short-term negative relationship between insecurity, exchange rates, lending rates, and inflows of capital, while a positive relationship was found between industrial production capacity, the consumer price index, and the total inflows of capital to Nigeria, with insecurity, exchange rates, the consumer price index, and lending rates being the most significant variables. In the long run, insecurity, lending rate, and consumer price index had no significant impact on inward capital inflows, while exchange rate and industrial production capacity exerted significant impacts on capital inflows. The lending rate had a negative impact on overall inflows of capital, whereas the exchange rate, industrial production capacity, and consumer price index had positive impacts. The exchange rate and industrial production capacity were the most important variables that affected capital inflows. Based on the ECM, it was realized that aggregate inward capital flows were stabilized by a factor of roughly 47.2% per quarter in order to reach long-run equilibrium. The Toda-Yamamoto causality tests indicated that the interactions between macroeconomic variables and insecurity strongly influenced capital flows to Nigeria. The overall findings suggested that promoting macroeconomic stability and combating insecurity could improve the investment climate, encouraging foreign capital flows into Nigeria.

Development of 'Kenalin' Learning Media Based on the Smart Apps Creator Application to Improve Student Learning Outcomes in Class IV Elementary School Science Subjects

Science and Technology learning in class IV at SD Negeri Kandri 01 is still not optimal in the use of IT-based learning media. This affects the learning outcomes of students who have not met the KKTP. This research aims to develop, and test the feasibility, and effectiveness of the "Kenalin" learning media based on the Smart Apps Creator application for the material Indonesiaku Kaya Budaya and also to find out whether the 'Kenalin' learning media can significantly improve student learning outcomes. This type of research is Research and Development (R&D) with the Borg and Gall development model. Using test techniques (pretest and posttest) and non-test techniques (observation, interviews, initial data analysis, and final data analysis). The data analysis method used in this research includes initial data analysis using the normality test, as well as final data analysis using the average difference test using theT-Test and measuring the average increase using N-Gain. Based on the results of material validation and media validation, it was found that the 'Kenalin' media met the standard criteria for being very worthy with a score of 92.50% from material expert validators and 95% from media expert validators. The effectiveness of using the 'Kenalin' media was assessed by comparing the pretest and posttest scores using the N- Gain test which obtained a score of 0.58 which was included in the medium category and the paired simple test obtained a result of 0.000 <0.005, so Ho was rejected and Ha was accepted. This research concludes that the "Kenalin" learning media based on Smart Apps Creator is suitable and effective for use as a learning media for the material My Indonesia is Rich in Culture, student learning outcomes also show a significant improvement.

A smarter approach to liquefaction risk: harnessing dynamic cone penetration test data and machine learning for safer infrastructure

This paper presents a novel approach for assessing liquefaction potential by integrating Dynamic Cone Penetration Test (DCPT) data with advanced machine learning (ML) techniques. DCPT offers a cost-effective, rapid, and adaptable method for evaluating soil resistance, making it suitable for liquefaction assessment across diverse soil conditions. This study establishes a threshold criterion based on the ratio of the penetration rate to the dynamic resistance (e/qd), where values exceeding four indicate high liquefaction susceptibility. ML models, including Support Vector Machine (SVM) optimized with Particle Swarm Optimization (PSO), Grey Wolf Optimizer (GWO), Genetic Algorithm (GA), and Firefly Algorithm (FA), were employed to predict the e/qd ratio using key geotechnical parameters, such as fine content, peak ground acceleration, reduction factor, and penetration rate. The SVM-PSO model demonstrated superior performance, with high R2 values of 0.999 and 0.989 in the training and testing phases, respectively. The proposed methodology offers a sustainable and accurate approach for liquefaction assessment, reducing the environmental impact of geotechnical investigations, while ensuring reliable predictions. This study bridges the gap between field testing and advanced computational techniques, providing a powerful tool for geotechnical engineers to assess liquefaction risks and design resilient infrastructures.

Technological Aspects of using 3D Printing Software in Construction

The relevance of introducing additive technologies of 3D printing in construction is to decrease the technological cycle of construction, and minimize expenditure and material costs, while reducing the duration of the development planning process and execution, eliminating inaccuracies and defects, as well as optimizing and automate the process. The technological aspect of 3D printing lies in the optimal selection of parameters based on the created 3D model using effective software. The purpose of the study is to determine the quality indicators of bricks obtained by 3D printing from special concrete. The approach to investigating this matter is rooted in ascertaining the compressive strength of concrete through non-invasive testing techniques, gauging the density of concrete using measurement methods, and validating the efficacy of integrating 3D printing technologies in construction by the method of comparative analysis. The effectiveness of introducing additive technologies of 3D printing was proven drawing upon quality indicators of concrete obtained on a 3D printer which meets all the requirements necessary for its implementation in the construction field. The selected characteristics of concrete compressive strength are fundamental to the basics of selecting a brand of concrete to be utilized in construction. The selected software demonstrated the capacity to generate flawless 3D designs. The result of the study shows a significant reduction in the number of workers involved in the construction process by 38–45%, depending on the chosen method of using 3D printing; a decrease of construction time by 33–42% when printing individual elements, blocks used in production, and by 61–72% when using a printer directly on the construction site; reduction of raw materials costs by 14–28%; as well as reduction of construction downtime by 25%. The results obtained indicate the need to develop and enhance progressive additive technologies for 3D printing in construction.