Performance Test Research Articles

Developing learning and training within industry model to improve work readiness of vocational high school students

<span lang="EN-US">Unemployment is still a national priority that needs to be addressed. In 2022, vocational high schools in Indonesia had the highest open unemployment rate. The highest open unemployment rate is a result of vocational high school students’ insufficient work readiness. Therefore, this research aims to develop a learning and training within industry (LTWI) model, and to evaluate the model’s efficacy in increasing vocational high school students’ work readiness. The research employed a research and development (R&D) design by Richey and Klein with the phases of needs analysis, internal validation, and external validation. There were 12 teachers and 89 students from the automotive engineering department at Muhammadiyah 1 Pakem Vocational High School and 1 Puring Vocational High School, as well as six instructors from the automotive industry: GAS Auto Service, Automotive Jogjakarta Center (OJC), Bengkel Barokah, and RND Auto Service, participated in the research. Data collection strategies adopted were interviews, questionnaires, and performance tests. The data were descriptively evaluated, and the conclusions were drawn using a categorization formula. With an average score of 3.43, the LTWI model can be used to learn very well. With an average final score of 3.32, the efficacy of the LTWI learning model falls into the category of “very good”. The LTWI model can be applied effectively to learning in vocational high schools since it has a positive influence on students’ work readiness.</span>

Highly durable perfluorosulfonic acid proton exchange membrane by combining inorganic free radical scavengers and organic antioxidants

In this work, a new type of complex was constructed by coordinating quercetin (QC) with cerium (Ce) ions. This complex was introduced into perfluorosulfonic acid resin (PFSA) to fabricate a proton exchange membrane. The coordination process prevented the formation of ion cross-links between cerium and sulfonic acid groups in PFSA, thereby keeping proton conductivity and fuel cell performance of membrane samples at a high level. Due to the insolubility of quercetin in water, its coordination with cerium minimized cerium migration, providing long-lasting resistance to free radicals. The effects of additives on PFSA membrane properties were investigated by measuring IEC, water uptake, swelling ratio, and proton conductivity. Fenton degradation experiments and membrane electrode assembly performance tests was conducted simultaneously. The results demonstrated that compared to the addition of quercetin or cerium alone, the use of QC-Ce increased the proton conductivity by 23.70% after 24-h Fenton degradation and lowered fluoride release by 58.29%. Meanwhile, the PFSA/QC-Ce composite membrane samples maintained an open circuit voltage of 0.935 V and a maximum power density of 668.15 mW cm−2 after 96 h of open circuit voltage hold testing.

Developing a hetero-intelligence methodological framework for sustainable policy-making based on the assessment of large language models

This work delves into the increasing relevance of Large Language Models (LLMs) in the realm of sustainable policy-making, proposing an innovative hetero-intelligence framework that blends human and artificial intelligence (AI) for tackling modern sustainability challenges. The research methodology includes a hetero-intelligence performance test, which juxtaposes human intelligence with AI in the formulation and implementation of sustainable policies. After testing this hetero-intelligence methodology, seven steps are rigorously described so that it can be replicated in any sustainability planning related context. The results underscore the capabilities and limitations of LLMs, underscoring the critical role of human intelligence in enhancing the efficacy of hetero-intelligence systems. This work fulfils the need of a rigorous methodological framework based on empirical steps that can provide unbiased outcomes to be integrated into sustainable planning and decision-making processes.-Assesses LLMs’ limitations and capabilities regarding sustainable planning issues-A replicable methodology is proposed based on the combination of both human and artificial intelligence-It proposes and systematises the integration of a hetero-intelligent approach into the formulation of sustainability policies to be more efficient and effective

Design and development of model for proton exchange membrane fuel cell

Fuel prices are rising, and fossil fuel resources are depleting. This fuel is consumed by conventional fuel vehicles, which contributes to increased greenhouse gas emissions and air pollution. Various vehicle technologies have been introduced in modern times. Among these innovations, fuel cell vehicle technology stands out due to its ease of use, robustness, and simplicity. The primary energy source for this system is hydrogen. Fuel cells use hydrogen to generate electricity through a chemical process that does not involve combustion. The purpose of this paper is to describe the design and development of a simulation model for a fuel cell (proton exchange membrane type) vehicle using mathematical equations and the MATLAB/Simulink R2020a software, taking into account all voltage losses and temperature variations of the proton exchange membrane (PEM) type fuel cell. The designed model is validated in two ways: first by generating V-I characteristics for the designed PEM-type fuel cell, and then by performing a performance test in Simulink using the driving cycle on one of the fuel cell vehicles. The obtained simulated results are nearly identical to the expected results, and the designed PEM-type fuel cell performed well in all real-time driving cycle test conditions.

Anti-seepage performance and underlying mechanism of carboxymethyl cellulose sodium-modified bentonite in hydraulic engineering applications

Bentonite is widely utilized in hydraulic engineering projects. However, its performance may deteriorate under extreme environmental conditions. Hence, we aim to develop a sodium carboxymethyl cellulose (CMC)-modified bentonite and investigate its anti-seepage performance. The results showed that the 10% CMC-modified bentonite exhibited the best performance. Compared with unmodified bentonite, the expansion index of 10% CMC-modified bentonite significantly increased to 40 mL/2 g, indicating a high water absorption capacity and expansion property. Moreover, it showed a significant decrease in permeability coefficient (3.72×10−11 m/s) and an increase in porosity (1.90), indicating its excellent anti-seepage effect. Furthermore, under unconventional environmental conditions and long-term performance tests, the 10% CMC-modified bentonite shows improved stability compared to the unmodified bentonite. Therefore, it can be concluded that this study provides support for the utilization of CMC-modified bentonite in anti-seepage engineering and hydraulic engineering applications.

Evaluation of Mechanical Joint Structural Performance through Actual Performance Testing of PC Connections

Evaluation of Mechanical Joint Structural Performance through Actual Performance Testing of PC Connections

Preparation and characterization of hydrophobic waterborne polyurethane self‐matting coating

AbstractA green method to synthesize self‐matting waterborne polyurethane acrylic hybrid emulsion with hydrophobic function is introduced in this study. A reactive waterborne polyurethane (RWPU) dispersion containing unsaturated CC double bonds was prepared from epoxidized soybean oil. Subsequently, the RWPU dispersion was copolymerized with fluorinated monomers of different carbon chain lengths to prepare polyurethane acrylic hybrid emulsion (PUF). The results revealed the gloss levels of PUF films to be as low as 12.4 gloss units at 60°. The morphology of PUF films was observed by scanning electron microscope and three‐dimensional surface profilometer, and the relationship between surface roughness and gloss was discussed in detail. In addition, thermal gravimetric analysis was conducted to determine the thermal stability of the PUF films, and the results denoted that these PUF films exhibited excellent thermal stability. Comprehensive performance tests indicated that the RWPU dispersion, which was copolymerized with hexafluorobutyl methacrylate at a weight of 10%, exhibited a low gloss, a high contact angle of 120°, and a high elongation percentage of 423%. Furthermore, the dynamic light scattering results showed small average particle size, revealing the excellent storage stabilities.

Development of 'OXIS Classification' calibration website for dental researchers.

The variations in interproximal contact areas have been categorised open (O), point (X), straight (I), and curved contact (S). This is based on their shapes and termed as OXIS classification. The interactive OXIS calibration website was developed to assist researchers seeking appropriate knowledge, minimise the overload of material, optimise efficiency in calibration and, to provide repositories for clinicians, healthcare workers, and policymakers. The website was developed in two phases. The first phase of development included expert group discussion, Focus Group Discussion (FGD), and the implementation of FGD recommendations. The second phase emphasised registration and development of the interactive web portal on OXIS classification. The developed website was subjected to user experience testing, functional testing, performance testing, security testing, device, platform testing, and then hosted. Calibrated students and faculties evaluated it with the help of Suitability Assessment of Materials (SAM) and System Usability Scale (SUS). Finally, after amendments, the website was evaluated by non-calibrated researchers and multidisciplinary experts. The total agreement was 74% for overall SAM category. Pooled mean total score of SUS was 52.7 (SD 7.17; range 45-67.5), indicating an average score. The content of the developed website has been evaluated as "satisfactory" and its technical quality as "of higher standards".

Diesel Fuel Stripping Systems for Enhanced Fuel Quality and Performance

Diesel fuel quality is essential for efficient engine performance, but stored diesel can accumulate contaminants over time, impacting engine efficiency and increasing maintenance costs. Diesel stripping systems, such as diesel strippers or diesel fuel polishing systems, play a crucial role in addressing these issues by effectively removing impurities and ensuring fuel purity. This paper examines the design, engineering, and operational aspects of diesel stripping systems, focusing on their ability to enhance fuel quality and optimize engine performance. Components like filters, pumps, separators, and steam stripping units work together, with steam stripping being a key method for removing light ends and hydrogen sulfide (H2S) from diesel. Design considerations, including system integration, material selection, and safety features, are critical for system effectiveness and reliability. Performance testing and maintenance practices ensure compliance with contaminant removal standards and sustain system efficiency. This research contributes to advancing diesel fuel management practices and identifies future trends for improved efficiency and environmental sustainability in diesel fuel purification technologies

Attitudes and Performance of Grade 11 Students in Pre-Calculus Using Strategic Intervention Material

Strategic Intervention Material (SIM) served as instructional support to help students review key ideas and techniques to help them master a competency-based ability they could not achieve during routine class discussions. This study aimed to determine the attitudes and the performance of Grade 11 students in Pre-Calculus using SIM at the three-identified public national high schools in Cebu, Philippines. It employed the descriptive-correlational method to collect data from 97 samples using two questionnaires (A standardized Attitudinal Test by Fennema-Sherman and researchers-made Performance Test in Equations of Circles). The Chi-square test, t-test, frequency, simple percentage, mean, standard deviation, and attitude toward success were used to analyze the respondents' attitudes about pre-calculus regarding confidence in learning, attitude toward success, mathematics as a male domain, and usefulness. The findings demonstrated that SIMs were appropriate for the respondents' needs, with more excellent knowledge gained from the SIM leading to a better understanding of Pre-Calculus, specifically Equations of Circles, which is beneficial when SIM is used as a teaching tool. The study concluded that using SIM in Pre-Calculus as instructional support significantly affected the student's performance in Pre-Calculus, which is effective in learning the subject. The proposed intervention plan was recommended to be implemented, monitored, and evaluated to boost the math performance of the Grade 11 senior high schools.

Characterization of low-damage cutting of alfalfa stalks by self-sharpening cutters made of gradient materials

Abstract The use of self-sharpening cutters can increase crop survival and regrowth by reducing the extent of stem damage incurred during the mowing stage and reducing the healing time at the harvest site. In this study, a self-sharpening cutter was prepared using a two-stage rare earth catalytic carbon–nitrogen–boron co-infiltration process, and the self-sharpening and wear-resistant properties of the cutter were verified by using metallographic organization testing, hardness testing, friction and wear performance testing, and the homemade tool wear test bench, and the low-damage cutting characteristics of the cutter were examined through field tests on alfalfa. The results show that the thickness of the penetration layer on the back face of a self-sharpening cutter made of gradient material is about 800 μm, with a maximum hardness of 1,800 HV. The coefficient of friction of the gradient material self-sharpening cutter is 67% lower than that of the commercially available 65Mn cutter. Gradient material self-sharpening cutter wear resistance is 2.15 times more than that of commercially available 65Mn cutter. The gradient material self-sharpening cutter reduces cutting damage by 11.42% compared to the commercially available 65Mn cutter. The application and promotion of self-sharpening cutting blades with gradient materials reduce alfalfa cutting damage, thereby improving reproductive yield.

Design, Construction, and Performance Testing of a Collapsible Parabolic Dish Solar Cooker for Temperature Control

This paper proposes solar energy as a viable alternative to biomass fuels for cooking, introducing a collapsible parabolic solar cooker designed to regulate heat production. The collector is divided into three sectors, with a specific condition for effective convergence of reflected radiation. The total concentration ratio is 89.4, with the primary sector covering 42%, while sectors 2 and 3 occupy 29% each. In the analysis ASAE protocol was employed. The results obtained from the ASAE S580.1 test revealed a range of cooking power values, with a minimum of 215.5 W and a maximum of 280.9 W. The single measure of performance of the cooker was gauged at 234.17 W. Regarding the Standard Stagnation Temperature, it was observed that a reduction of the collector area by 0.343݉ଶ resulted in a temperature decrease of 59.5℃. The highest recorded SST for the entire solar cooker (when all three sectors were expanded) reached 279℃.

Dictionary-based sentiment analysis of monetary policy communication: on the applicability of lexicons

AbstractIn this study, we discuss central bank communication sentiments assessed using different dictionaries. Policy communication by monetary authorities is considered an essential additional policy tool. Various text-mining techniques could evaluate its sentiment. Dictionary methods are a prominent example here because they offer simplicity and are a starting point for applying more elaborate methods. We decided to test four lexicons: generic, economic and financial and two domain-specific lexicons to conclude on their applicability to assess the sentiments of monetary releases and provide recommendations for their further application. This study surveys four lexicons qualitatively and conducts a few exercises: lexicon content comparison, performance tests for highly positive and negative messages, and statistical tests of dictionary alignment and correlation. The sample covers small open economies implementing inflation targeting. The study concludes that all investigated dictionaries could be used for detecting central bank intentions: they do not return contradictory results. The choice among them for a particular study depends on the study’s setup and goals—as presented in our recommendations

Micropatternable Ink Composed of MAX Phase ZIF-8 for Gas Sensing Applications

This work provides a detailed introduction to the preparation methods, structural characteristics, and various performance tests of the Ti3C2/ZIF-8 composite material. Initially, the composite material is obtained through the synthesis, mixing, and subsequent processing of MXene solution and ZIF-8 nanoparticles. The coating structure and properties were comprehensively characterized using SEM, TEM, and XRD. These analyses revealed the material's layered structure, high crystallinity, and surface activity. BET analysis of Ti3C2/ZIF-8 also shows excellent gas adsorption-desorption performance, having an especially high-efficiency adsorption capacity for VOCs. TGA further demonstrates the thermal stability and chemical stability of Ti3C2/ZIF-8 and its printability was tested indicating widespread application potential in coating preparation through ultrasonic spray technology. Finally, we show methods to regulate and control coating thickness and roughness for precision manufacturing. These analyses together emphasize the application value of Ti3C2/ZIF-8 in fields such as gas-storage, gas-separation, and environmental monitoring.

Two-Method Indoor Laboratory Instruction: How Effective Is It on Secondary School Students’ Performance in Physics?

This study probed the effectiveness of two-method indoor laboratory instruction on secondary school students’ performance in physics in Jos Metropolis, Nigeria. The quasi-experimental research design of the non-equivalent control group pre-test, post-test type was employed. The population for the study comprised 1,112 senior secondary two students offering physics in 18 schools in Jos metropolis, with the schools purposively obtained. The study sample consisted of 80 SSS II students obtained from two intact classes, one class each from two schools selected using simple random sampling technique. Two research questions were raised and two hypotheses were formulated. Physics Performance Test (PPT) was the instrument validated and used to gather data. The test-retest method was used to obtain the reliability of PPT and its coefficient was computed as 0.73 using Kuder-Richardson formula 21 (K-R 21). Mean and standard deviation were used to answer the research questions while independent t-test of difference and Analysis of Covariance (ANCOVA) were the statistical tools used to test the hypotheses at 0.05 levels of significance. The results revealed that students taught concepts of simple harmonic motion and elasticity using group indoor laboratory method performed better than their counterparts taught using individual indoor laboratory method; although male students performed slightly higher than their female counterparts after exposure to the two methods, gender was found to have no interaction effect on their performance; there was a significant interaction effect of treatments and gender on students’ performance in the study area, with the methods as source of interaction effect. Based on the findings, recommendations were made, which include that curriculum developers should ensure that laboratory teaching methods are included in physics curriculum in order to enhance students’ performance in the subject.

Balanced Mix Design Plus for Mixtures that Contain Recycled Asphalt Pavement

Recent efforts have been made to include mixture performance tests at the mix design stage using so-called “balanced” mix design (BMD). This paper evaluates the use of two mixtures that contain intermediate and high recycled asphalt pavement contents in the context of a BMD approach referred to as balanced mix design plus (BMD+). BMD+ utilizes the dynamic modulus, cyclic fatigue, and stress sweep rutting tests and mechanistic models and has three tiers of design based on the amount of performance testing required. As part of the BMD+ approach, index–volumetrics relationships (IVRs) and performance–volumetrics relationships (PVRs) based on the four-corner concept were developed for the two mixtures and verified using the performance data from seven other volumetric conditions. The developed PVRs were used to perform BMD+ Tier 3 analysis of the two mixtures, whereas the IVRs based on two points at the target air void content of 4% were used to conduct BMD+ Tier 2 analysis. The results indicate that the use of BMD+ Tier 2, which requires performance tests at only two conditions and without pavement simulations, yields longer lasting mixtures compared with Tier 1, which follows the Superpave volumetric mix design method. It was also found that Tier 3 requires more testing and pavement simulations but leads to even further gains in predicted life duration compared with Tier 2.

OphthalMimic: A new alternative apparatus without animal tissue for the evaluation of topical ophthalmic drug products

The necessity of animal-free performance tests for novel ophthalmic formulation screening is challenging. For this, we developed and validated a new device to simulate the dynamics and physical–chemical barriers of the eye for in vitro performance tests of topic ophthalmic formulations. The OphthalMimic is a 3D-printed device with an artificial lacrimal flow, a cul-de-sac area, a support base, and a simulated cornea comprised of a polymeric membrane containing poly-vinyl alcohol 10 % (w/v), gelatin 2.5 % (w/v), and different proportions of mucin and poloxamer, i.e., 1:1 (M1), 1:2 (M2), and 2:1 (M3) w/v, respectively. The support base is designed to move between 0° and 50° to replicate the movement of an eyelid. We challenged the model by testing the residence performance of poloxamer®407 16 % and poloxamer®407 16 % + chitosan 1 % (PLX16CS10) gels containing fluconazole. The test was conducted with a simulated tear flow of 1.0 mL.min−1 for 5 min. The OphthalMimic successfully distinguished PLX16 and PLX16C10 formulations based on their fluconazole drainage (M1: 65 ± 14 % and 27 ± 10 %; M2: 58 ± 6 % and 38 ± 9 %; M3: 56 ± 5 % and 38 ± 18 %). In conclusion, the OphthalMimic is a promising tool for comparing the animal-free performance of ophthalmic formulations.

Establishment and validation of an artificial intelligence web application for predicting postoperative in-hospital mortality in patients with hip fracture: a National cohort study of 52,707 cases.

In-hospital mortality following hip fractures is a significant concern, and accurate prediction of this outcome is crucial for appropriate clinical management. Nonetheless, there is a lack of effective prediction tools in clinical practice. By utilizing artificial intelligence and machine learning techniques, this study aims to develop a predictive model that can assist clinicians in identifying geriatric hip fracture patients at a higher risk of in-hospital mortality. A total of 52,707 geriatric hip fracture patients treated with surgery from 90 hospitals were included in this study. The primary outcome was postoperative in-hospital mortality. The patients were randomly divided into two groups, with a ratio of 7:3. The majority of patients, assigned to the training cohort, were used to develop the AI models. The remaining patients, assigned to the validation cohort, were used to validate the models. Various machine learning algorithms, including logistic regression (LR), decision tree (DT), naïve Bayesian (NB), neural network (NN), eXGBoosting machine (eXGBM), and random forest (RF), were employed for model development. A comprehensive scoring system, incorporating 10 evaluation metrics, was developed to assess the prediction performance, with higher scores indicating superior predictive capability. Based on the best machine learning-based model, an AI application was developed on the Internet. In addition, a comparative testing of prediction performance between doctors and the AI application. The eXGBM model exhibited the best prediction performance, with an AUC of 0.908 (95% CI: 0.881-0.932), as well as the highest accuracy (0.820), precision (0.817), specificity (0.814), and F1 score (0.822), and the lowest Brier score (0.120) and log loss (0.374). Additionally, the model showed favorable calibration, with a slope of 0.999 and an intercept of 0.028. According to the scoring system incorporating 10 evaluation metrics, the eXGBM model achieved the highest score (56), followed by the RF model (48) and NN model (41). The LR, DT, and NB models had total scores of 27, 30, and 13, respectively. The AI application has been deployed online at https://in-hospitaldeathinhipfracture-l9vhqo3l55fy8dkdvuskvu.streamlit.app/, based on the eXGBM model. The comparative testing revealed that the AI application's predictive capabilities significantly outperformed those of the doctors in terms of AUC values (0.908 vs. 0.682, P<0.001). The eXGBM model demonstrates promising predictive performance in assessing the risk of postoperative in-hospital mortality among geriatric hip fracture patients. The developed AI model serves as a valuable tool to enhance clinical decision-making.

Performance optimization and testing of a novel energy coupled actuated high-speed valve based on peak-and-hold driving strategy

High-speed on/off valve acts as critical enabling component of digital hydraulics, which has been challenging the traditional hydraulic system by providing efficient and effective hydraulic control solutions. The high-speed on/off valve that ideally fits the digital hydraulic system is expected to achieve fast response and long stroke with affordable energy consumption. This not only requires developing advanced actuation mechanism but also demands extensive study on the driving strategy. This study focuses on investigating the Peak-and-hold driving strategy applied to a novel high speed on/off valve-energy coupling actuated valve (ECAV), in order to achieve target performance with optimized energy consumptions. This work has developed an electro-mechanical coupled physics model based on commercial finite element solver COMSOL. This model helps to investigate the performance of ECAV under different peak-and-hold driving parameters and thereby recommend the optimal peak-and-hold driving strategy. Then, the experimental testing on the prototype ECAV has been conducted to validate the simulated performances. The measurement results showed that the prototype ECA using the optimal peak &amp; hold solution demonstrated significant advantage in energy saving targeting at response of 10 ms for 1.5 mm stroke, especially compared to a typical step input signal.

Performance test of half-wave resonator (HWR) superconducting cavities

Performance test of half-wave resonator (HWR) superconducting cavities