Correlation Technique Research Articles

Consumer Attitude and Purchase Intention towards Organic Food in Kritipur, Kathmandu

This study examined the relationship between consumer attitudes and purchase intentions toward organic products in Kritipur, Kathmandu. Using a 5-point Likert scale survey, data from 57 respondents were analyzed through correlation and regression techniques. The results reveal a considerable positive impact of consumer attitudes, specifically health concerns and environmental care, on purchase intention, with an unstandardized coefficient of 0.854 (p < .001). Consumer attitudes explained 64.7% of the variance in purchase intention, confirming the critical role of favorable attitudes in promoting organic product purchases. However, contrary to the hypothesis, subjective norms had a negative influence on purchase intention (β = -0.261, p = .004), indicating that social pressures may decrease consumer willingness to buy organic products. The findings suggest that marketers should focus on increasing consumers' trust in organic products and emphasize the health and environmental benefits to increase sales. This study expands existing theoretical models by incorporating health concerns and environmental care as crucial factors influencing consumer attitudes towards organic food.

Biomechanics of physical exercise: A data-driven approach to enhancing mental health in college students

With growing awareness of the importance of mental health, the biomechanical mechanisms of physical exercise have gained attention as an effective intervention for improving mental well-being, particularly among college students. Physical activity not only enhances physical fitness and disease resistance but also contributes to cognitive and emotional health through specific biomechanical pathways. This study explores the interplay between exercise biomechanics and mental health by investigating the psychological challenges faced by college students. Utilizing advanced data analysis and correlation techniques, we refine the Apriori algorithm through a novel database partitioning strategy, achieving a 23.68% improvement in accuracy and a 10.17% reduction in runtime compared to the baseline. Additionally, this study examines how biomechanical factors, such as joint movement and muscle activity, influence brain function and mental health outcomes. The findings offer innovative perspectives for integrating biomechanical insights into mental health education and exercise-based interventions for college students.

Full-field quantitative visualization of shock-driven pore collapse and failure modes in PMMA

The dynamic collapse of pores under shock loading is thought to be directly related to hot spot generation and material failure, which is critical to the performance of porous energetic and structural materials. However, the shock compression response of porous materials at the local, individual pore scale is not well understood. This study examines, quantitatively, the collapse phenomenon of a single spherical void in PMMA at shock stresses ranging from 0.4 to 1.0 GPa. Using a newly developed internal digital image correlation technique in conjunction with plate impact experiments, full-field quantitative deformation measurements are conducted in the material surrounding the collapsing pore for the first time. The experimental results reveal two failure mode transitions as shock stress is increased: (i) the first in situ evidence of shear localization via adiabatic shear banding and (ii) dynamic fracture initiation at the pore surface. Numerical simulations using thermo-viscoplastic dynamic finite element analysis provide insights into the formation of adiabatic shear bands (ASBs) and stresses at which failure mode transitions occur. Further numerical and theoretical modeling indicates the dynamic fracture to occur along the weakened material inside an adiabatic shear band. Finally, analysis of the evolution of pore asymmetry and models for ASB spacing elucidate the mechanisms for the shear band initiation sites, and elastostatic theory explains the experimentally observed ASB and fracture paths based on the directions of maximum shear.

The Relationship Between Confidence and Anxiety in Facing the Workforce Among Final-Semester Students

This study aims to determine the relationship between self-confidence and anxiety in facing the world of work in final semester students at the Faculty of Technologies, South East Technological University. The method used in this study is the person correlation research method. Data collection techniques using the scale method. The self-confidence scale and anxiety scale in dealing with the world of work are measured using the Likert scale model. On the self-confidence scale, there are 40 items and on the anxiety scale in dealing with the world of work, there are 40 items. The reliability coefficient for the self-confidence scale is 0.447 and the reliability coefficient for the anxiety scale in facing the world of work is 0.408. To find out the relationship between self-confidence and anxiety in facing the world of work in final semester students, the Pearsion correlation technique was used. The results of this study's data analysis showed a significant value of the relationship between anxiety and self-confidence of 0.000 <0.05 which indicates that there is no relationship between self-confidence and anxiety. The result of obtaining the pearson correlation between the two variables is -0.002. This can be interpreted that the relationship between anxiety and self-confidence has a negative direction and is not significant. This means that the research hypothesis is accepted. In other words, there is a negative relationship between self-confidence and anxiety in facing the world of work in final semester students at the Faculty of Psychology, South East Technological University.

Moisture dependent bending mechanical properties of Chinese fir

ABSTRACT Predicting the long-term deformation and failure of wood under varying environmental conditions is challenging due to the complex rheological behaviour of wood. In this study, the bending failure mechanism and moisture-dependent viscoelastic creep behaviours of Chinese fir (Cunninghamia lanceolata [Lamb.] Hook.) were explored. The digital image correlation technique was used to monitor strain field changes during the bending process. The results revealed that wood in a dry state was more brittle than in a moist state. Strain field variations showed that the tensile load on the tension side primarily governs bending failure. There are distinct differences between tension and compression regions by fracture morphology analysis. The study further developed the time-moisture-stress superposition principle to integrate the effects of time, moisture, and stress on wood's creep behaviour in bending. These findings provide critical insights into how moisture affects wood’s mechanical behaviour, guiding more efficient design and manufacturing practices for long-term structural performance in the timber-construction industry.

Suppression of core temperature fluctuations by edge cooling in the J-TEXT tokamak

Abstract The suppression of core temperature fluctuations due to edge cooling in the J-TEXT tokamak is presented. The supersonic molecular beam is injected into the low density plasmas and the core temperature rise appears. The staggered time correlation technique is utilized to infer the temperature fluctuations from an electron cyclotron emission radiometer (ECE). The existing correlation ECE (CECE) also enables the observation of the temperature fluctuations simultaneously. A significant flattening of the density gradients appears almost in the whole plasmas after the cold pulse injection. The behaviors of the temperature fluctuations from both ECE and CECE show a good agreement, except for the fluctuation level, which exhibits a relative variation of approximately 10% − 50%. The relative intensity of temperature fluctuations decreases within the surface of r / a ∼ 0.8 due to the edge cooling. The cross-power analysis and the agreement in measurements suggest that temperature fluctuations from turbulence inferred from a single ECE channel may be possible. Linear simulations suggest the drop in temperature fluctuation intensity may relate to the trapped electron mode turbulence stabilization. This paper also demonstrates the evolution of both gradients and fluctuations before and after supersonic molecular beam injection with density scans.

Axial Compressive Behavior and Calculation Model for Axial-Compressive-Load-Carrying Capacity of Locally Corroded RC Short Columns

The individual effects of the main reinforcement corrosion and stirrup corrosion on the axial compressive behavior of reinforced concrete (RC) columns were evaluated through axial compression tests on 10 full-scale short columns. The primary experimental parameters were the corrosion location and the corrosion ratio of the steel bar. The electrochemical accelerated corrosion method was applied on nine of the columns, including three columns corroded in the main reinforcement, three columns corroded in the stirrup, and three columns corroded in both the main reinforcement and stirrup. The full-field displacement of the column and strain of concrete were evaluated using a non-contact 3D-DIC (digital image correlation) technique. The results indicated that, with the increase in the main reinforcement corrosion ratio, the width of the longitudinal corrosion crack increased. The transverse corrosion cracks appeared when the stirrup corrosion ratio is larger than 8%, and the increase in stirrup corrosion ratio increased the crack number, but had little effect on the crack width. Compared to the non-corroded RC column, the peak load of specimens with main reinforcement corrosion ratios of 8.02%, 9.01%, and 19.27% decreased by 10.53%, 13.56%, and 19.77%, respectively, and that of the specimens with stirrup corrosion ratios of 7.08%, 12.33%, and 24.36% decreased by 11.59%, 12.07%, and 17.15%, respectively. The axial-compressive-load-carrying capacity of RC columns decreased almost linearly as the corrosion ratio of the main reinforcement increases, while it exhibited an approximately bilinear degradation as the corrosion ratio of the stirrups increases. The stirrup corrosion ratio had less effect on the axial compressive loading capacity of the RC column when it was larger than 7.5%. A model for calculating the axial-compressive-load-carrying capacity of the corroded RC short columns was developed based on the impact mechanisms of the corroded main reinforcement and stirrups on the columns’ axial compressive behavior. The calculated results closely matched the test data, demonstrating that the proposed model can reliably predict the residual load-carrying capacity of corroded columns.

Anisotropy in shear failure of shale: An insight from microcracking to macrorupture

Anisotropic shear failure in shale is crucial to wellbore instability and hydraulic fracturing. While previous studies have examined bedding angles ranging from 0° to 90°, the intermediate angles have not been thoroughly investigated, with limited quantitative analysis from microcracking to macrorupture. To address this gap, we conducted direct shear tests on cubic shale samples with seven bedding angles (α = 0°, 15°, 30°, 45°, 60°, 75°, and 90°) using an innovative combination of acoustic emission (AE) and digital image correlation (DIC) techniques. This approach allowed us to gain a comprehensive understanding of the cracking damage process from the interior to the surface. Under various normal stresses, the minimum peak shear strengths occurred at α = 0°, while the maximum values were observed at α = 45° or 60°, rather than remaining constant. The internal friction angle peaked at α = 45°, not at α = 30° as previously reported. Furthermore, the shear failure pattern was influenced by complex interactions among nominal shear plane, bedding structure, and normal stress. The primary strain concentration zones and microfractures formed not only along the nominal shear plane but also along the bedding planes. Notably, microcracking damage initiated most readily at α = 0°, where the b value in AE events was higher and the fractal dimension was lower. At α = 30°–60°, the b value reached its minimum, while the fractal dimension peaked. The more random distribution of larger-scale microcracks was associated with an increase in the shear strength. These findings provide critical insights into the anisotropy of shear failure in shale and demonstrate the potential of microcracking analysis in predicting critical macrorupture and shear resistance. The identification of three distinct shear failure mechanisms further enhances our understanding of shale anisotropy.

Whole process analysis on splitting tensile behavior and damage mechanism of 3D/4D/5D steel fiber reinforced concrete using DIC and AE techniques

In recent years, the application of a new type of end hook steel fiber (ESF) in concrete has gradually become a hot spot due to its excellent properties. In order to investigate the influences of ESF content, end hook number and aspect ratio on the splitting tensile properties and damage characteristics of end hook steel fiber reinforced concrete (ESFRC), a set of splitting tensile test device was improved in this study to measure the complete splitting tensile load-deformation curves of ESFRC. The influence of 3D/4D/5D steel fiber on the crack development and damage evolution of ESFRC specimens under splitting tensile load was analyzed by digital image correlation (DIC) and acoustic emission (AE) techniques. The results showed that the splitting tensile strength and crack resistance of ESFRC were gradually improved by increasing the content and end hook number of ESF. The splitting tensile load-deformation curves of the specimens with single-ended hook (3D) steel fibers could be divided into five stages, and the curves appeared two or even more fiber strengthening stages with the increase of end hook number, which mainly depends on the end hook form of steel fiber. Concrete cracking, ESF debonding and end hook straightening were the main reasons for the development of AE events and ringing counting. As the ESF content or the number of end hooks increased, the proportion of shear cracks gradually increased from 59.82% to 71.34%, and the AE energy of cracking damage also increased accordingly. The strain band at the failure interface first appeared in the middle of the specimen and gradually extended to the loading end, and the failure mode gradually changed from a single crack to a main crack, accompanied by multiple scattered cracks. Finally, a prediction model for the splitting tensile strength of ESFRC was proposed and verified based on the fiber pull-out bonding theory.

Investigation of scale effects of rock bridges based on Multi-Physical field monitoring

The presence of rock bridges is crucial for ensuring the stability of rock slopes. However, evaluating the mechanical properties of rock bridges solely based on the joint persistence coefficient (K) raises doubts due to potential variations in the scales of rock bridges within a rock mass with a constant K value. In this study, direct shear tests with different scales were carried out on sandstone specimens. Acoustic Emission (AE) and Digital Image Correlation (DIC) techniques were utilized to monitor the damage procession of the specimens. The evolution process of the specimen was divided into stages and three threshold points were determined based on AE parameters. As the scale decreased, the Joint Roughness Coefficient (JRC) increased, the tensile failure increased, and the shear failure decreased. As the normal stress increased, the JRC with the same scale decreased, the tensile failure decreased, and the shear failure increased. The change of fracture mechanism was the primary reason for the strength deterioration with decreasing scales. The decrease of the scale was not conducive to the failure prediction. By improving the rock bridge failure potential (RBP) index, the proposed RBPn index could appropriately characterize scale effects under different normal stresses.

Damage model of NC-UHPC interface zone in UHPC wet joint based on DIC

The bond interface of the ultra-high performance concrete (UHPC) wet joint composed of normal concrete (NC) and UHPC is a weak part, which can easily damage the interface zone and affects the structure's safety. However, the damage model of the NC-UHPC interface zone in UHPC wet joint has not been carried out yet. In this study, firstly, the effects of different interfacial moisture content and interfacial roughness on the interfacial bond strengths were investigated by splitting tensile tests, NC-UHPC specimens with different interfacial bond strength were obtained, and digital image correlation (DIC) technique was used to obtain the strain evolution regulation of the NC-UHPC interface zone; Secondly, the extended interface zone damage factor Df was used to investigate the damage differences of NC-UHPC interface zone with different bond strengths; Finally, the damage model of NC-UHPC interface zone with different interfacial bond strengths was established. This research will be of great significance in improving the theoretical system of UHPC wet joint structure design.

Effect of delignification on shrinking and swelling of poplar wood assessed using digital image correlation technique.

This study investigates lignin's influence on the hygroscopic behavior of poplar wood. Delignification was achieved using an acidic NaClO2 solution, and digital image correlation (DIC) was employed to measure strain distribution during shrinking and swelling across relative humidity (RH) ranging of 0 % to 97 %. Results showed that lignin removal increased equilibrium moisture content (EMC) by up to 3.6 % in samples with 27 % lignin reduction. Strain analysis revealed significant radial strain differences between earlywood and latewood, with tangential strain suppressed by wood rays. Increased porosity and cellulose slippage were observed following lignin removal, and samples with the highest lignin removal rate exhibited reduction exhibited over 58 % greater εxx and over 43 % greater εyy compared to untreated wood. These effects were most pronounced in latewood and regions distant from wood rays, where stress concentrations occurred. Delignification-induced cell wall thinning amplified the wood rays' inhibitory effect on anisotropic deformation during shrinking，enhancing the contrast between isotropic deformation in latewood and anisotropic deformation in earlywood during swelling. These findings provide insights into lignin's role in wood-water interactions, supporting the optimization of wood modification techniques.

Forecasting Power Consumption in the DSL Access Network System based on Network Activities by using Machine Learning

The widespread telecommunication networks and Internet services like Digital Subscriber Line (DSL) access has contributed to the growing demand of electricity. With environmental consciousness arising from non-renewable energy sources, coupled with rising demand, industries need to implement green strategies. This research focuses on predicting power consumption in DSL access networks using machine learning approaches. With an emphasis on Very High Bit Rate Digital Subscriber Line 2 (VDSL2) technology, the study investigates DSL modem’s power usage under an ideal and a bridge tap faulty conditions of copper cable along distances ranging from 100 to 1000 meters. The different levels of network activities are generated by IxChariot software and Pearson’s correlation techniques are used to analyse the relationship between power consumption and network activities. Combining the Train-Valid-Test and Random Forest algorithms, a predictive Machine Learning model is developed to forecast the power consumption based on relevant variables. The results show that power consumption tends to increase as the network activities are heavier and the proposed model presents a low minimum absolute error as a good model to forecast the power. It may aid Internet service providers to predict the optimum power limit in the network systems and pursue further investigation on how to reduce electricity use in the telecommunication field.

The Mediating Effect of ICT-Based Instruction on Attitudes and Motivation of Students’ in Science

This study determined the mediating role of ICT-based instruction on the relationship between attitudes and motivation of students in science. The quantitative approach using the correlational technique and analysis was utilized in this study with a sample of 309 students coming from the Public Schools in the Division of Bukidnon, Municipality of Kitaotao, Kitaotao I, Kitaotao II, and Kitaotao III Districts using stratified random method of sampling. Data from the respondents was collected using sets of modified survey questionnaires, and the results were analyzed for reliability and content validity. Regression analysis, Pearson-r, and the mean were used to examine the data. The findings showed that the levels of science attitudes of students were rated moderate, and the science motivation of students was rated high. While ICT-based instruction was likewise given a high rating. Furthermore, there was a strong correlation between the factors. The connection between science attitudes and the science motivation of students was significant. There is also a significant relationship between science attitudes of students and ICT-based instruction. And a significant relationship between ICT-based instruction and the science motivation of students. On the mediating effect, a partial mediation exists between the impact of ICT-based instruction on the correlation between attitudes and motivation of students in science.

Study and mechanism analysis on fracture mechanical properties of steel fiber reinforced recycled concrete (SF-R-RC)

Recycled concrete has deficiencies in its overall performance due to the deteriorated properties of the recycled aggregate (RA) used. Based on the RA characteristics and fiber reinforcement mechanism, designing recycled concrete by adding steel fiber (SF) and enhancing RAs in a coordinated manner can effectively improve the overall performance of recycled concrete. Therefore, this paper considers the SF content and RA enhancement to study the fracture mechanical properties of steel fiber reinforced recycled concrete (SF-R-RC), and the main conclusions are as follows: the fracture mechanical properties of SF-R-RC are significantly affected by aggregate enhancement and SF content. Without the SFs, the strengthened coated recycled aggregate concrete (CRAC) was better than unreinforced recycled aggregate concrete (RAC) in terms of the unstable fracture load, fracture energy, initial fracture toughness and unstable fracture toughness, but weaker than normal aggregate concrete (NAC). The increase in the unstable fracture load, fracture energy, initial fracture toughness and unstable fracture toughness of NAC, RAC and CRAC with the increase in SF content was observed, with CRAC showing the most significant increase in these fracture parameters. Applying digital image correlation (DIC) and acoustic emission (AE) techniques, the effect of SF content and RA enhancement method on the crack evolution process and damage distribution law of SF-R-RC was studied. Meanwhile, the microscopic testing technique was used to reveal the mechanism of the influence of SF and RA enhancement on the fracture mechanical properties of SF-R-RC. The research results of this paper provide a theoretical basis for the application of RA enhancement and SF reinforcement methods of recycled concrete in practical engineering.

The Barriers to Effective Remote Education, Including Access to Technology, Student Engagement and Teacher Preparedness

This study focuses on barriers and facilitators in distance education in higher education institutions with regard to access to technology, student engagement, and teacher preparedness. The research study was conducted with a quantitative method to collect data. The self-administered questionnaire was administered to 258 students and 70 faculty members from several universities and colleges from Punjab, Pakistan, selected from the Islamia University of Bahawalpur, BZU University, Emerson College University, and the Women University Multan. The participants were selected using snowball sampling. The data was analyzed using correlation, regression, and post-hoc statistical techniques aided by the SPSS software. The research findings showed that access to technology is significantly related to student engagement, teacher preparedness, as well as impact of student engagement on academic performance and learning satisfaction. The regression analysis further confirmed that higher student engagement levels are linked with better learning outcomes. Additional post-hoc tests confirmed that teacher preparedness significantly influences student engagement. Findings suggest that access to technology and training in its application are essential for enhancing the quality of remote education. It means that improvement needs are noted in policy change concerning equable access to technology and additional investments in developing teachers in online environments.

Hubungan Konformitas dengan Kepuasan Hidup pada Mahasiswa Pengguna Media Sosial Instagram di Yogyakarta

Individuals who have low life satisfaction tend to change their current situation, so they have a greater orientation to make changes to their lives, which triggers an individual to do conformity, which conformity itself is interpreted as the tendency tochange individual beliefs or behaviors to match the behavior of others. This study aims to find out whether there is a relationship between conformity and life satisfaction in students who use Instagram social media in Yogyakarta. The data collection method in this study uses two likert scales, namely: the life satisfaction scale and the conformity scale. The subject of this study is students who use Instagram social media in Yogyakarta with a vulnerable age of 17-24 years, the sample used a purposive sampling technique totaling 100 respondents. Based on the results of the study conducted with the Pearson product moment correlation technique, the significance figure p = 0.000 (p< 0.05) this shows a significant relationship between the variable of life satisfaction and conformity in students who use Instagram social media in Yogyakarta.

Exploring the Effects of Integrated Corporate Social Responsibility on the Financial Performance of Project-Oriented Organisations

This article embarks on an in-depth exploration of how corporate social responsibility (hereafter: CSR) shapes the financial performance (hereafter: FP) of Project-Oriented Organizations (hereafter: POOs) within Morocco's dynamic construction sector. By adopting a diligent quantitative research method, this research meticulously examined a diverse sample of 250 organizations through advanced correlation and multivariate linear regression techniques. The results illuminate a compelling and noteworthy favourable relationship between CSR initiatives and the FP, indicating that ethical business practices profoundly enhance economic outcomes. By focusing on the distinctive Moroccan landscape, the article sheds light on the remarkable challenges and opportunities faced by POOs, showing an understanding of the financial benefits of CSR. Acknowledging its limitations, the study suggests avenues for future research and perspectives founded on HSDG wisdom. It advocates the HESG framework by integrating a human-centric approach to encourage healthy, equitable and sustainable societal evolution. The study provides actionable recommendations for policymakers, business leaders, and scholars aiming at promoting sustainable economic growth and long-term societal well-being.

Tensile Fracture Initiation and Propagation of Granite and Gneiss at Wedge Splitting Tests: Part 2—Fracturing Studies Based on Digital Image Correlation and Thin Section Analysis

AbstractThe crack development in quasi-brittle granite and brittle gneiss under mode I loading condition was monitored using digital image correlation (DIC) technique during wedge splitting tests. The cracking behavior was studied on granite specimens that were split in one material direction, perpendicular to the rift plane, and gneiss specimens that were split in three different material directions, parallel and perpendicular to the foliation (along and across a lineation). The granite specimens had a saw cut 5 mm-wide notch and a blunt round notch in form of a 32 mm borehole. The gneiss specimens had a saw cut notch. The results from the DIC measurements revealed a meandering and branching crack path for the granite, whereas a smoother crack path for the gneiss with almost no branching. This behavior was confirmed by microscopy images from thin sections taken from specimens after testing. The thin sections showed that the fractures were prone to propagate across grains in the more coarse-grained granite than in the fine-grained gneiss, where the fractures propagated almost entirely along grain boundaries. The crack initiation occurred mainly in the corner of the saw cut notches and centrally in the round notch. However, the initiation locations in the granite were affected by the medium- to coarse-grained microstructure with grains preventing initiation and propagation which yielded displaced positions out from the ideal ones with respect to the highest stress in some cases. The crack opening displacement was determined along the crack path from the DIC measurements at 12 stages on each specimen of the advancing crack during the splitting progress. The critical crack opening displacement and length of the fracture process zone were assessed and the crack front position yielding the crack length along the tests was determined. The results showed a critical crack length when the deformations in the ligament (also called plastic hinge) affected the cracking process. The average crack velocity in gneiss during the test was more than twice as high as in the granite. This is attributed to a combined effect of the higher brittleness in the gneiss and the effect of a too large elastic energy in the specimen and test setup in relation to the dissipated fracture energy which made the initial crack propagation in the gneiss specimens nearly unstable. The strain energy release rate was calculated along the crack propagation and showed a lower value when the crack lengths were less than 40–60 mm. The calculation of the strain energy release rate was made on crack length measurements from DIC results. The results from the investigation were discussed in relation to the few other similar results found in the literature. The findings give an insight and understanding of the cracking process via both qualitative and quantitative results. Several used methods were novel or not used together in a single study as in this one.

Pengaruh Media Pembelajaran Terhadap Hasil Belajar Siswa

This study aims to examine the effect of the Kahoot learning media on student learning outcomes at SMK Pelita Tiga Jakarta. The use of Kahoot as a learning media was chosen due to its efficiency, innovativeness, and ability to help achieve learning objectives at a lower cost. The research method used is a quantitative approach with a correlation method. This study involved 24 students selected using the Cluster Sampling technique. Data collection was conducted through questionnaires and documentation, while data analysis was performed using the product moment correlation technique. Based on calculations, the product moment correlation value for 24 degrees of freedom (df) at a 5% significance level is 0.404, and at a 1% significance level is 0.515. The analysis results show that the observed correlation value (ro) of 0.617 is greater than the table value (rt) at both significance levels. Therefore, the null hypothesis is rejected, and the alternative hypothesis is accepted, indicating a positive effect of Kahoot learning media on student learning outcomes at SMK Pelita Tiga Jakarta. The implication of this study is that Kahoot can be an effective alternative learning media to improve student learning outcomes.