{"results":[{"id":"doaj_10.3390/fluids11020052","title":"A Vortex-Induced Correction Method for Pressure Loss Prediction in Fluid Network Theory","authors":[{"name":"Xiaoping Wang"},{"name":"Liqiang Liang"},{"name":"Qingsong Song"},{"name":"Yunguang Ji"},{"name":"Mingxu Sun"},{"name":"Hongtao Li"}],"abstract":"Traditional fluid network theory often underestimates pressure losses in complex pipe-bundle systems operating under vortex-dominated flow conditions, with deviations exceeding 20% in many cases. To address this limitation, this study proposes a vortex-based correction method. Three-dimensional simulations were performed on a multidirectional parallel pipe bundle to analyze vortex formation and to quantify the effects of fluid properties (viscosity and inlet velocity) and structural parameters (branch diameter, manifold cross-sectional ratio, and manifold arrangement) on pressure loss. To account for vortex-induced energy dissipation that is overlooked by conventional one-dimensional network models, an additional vortex-induced loss coefficient, α, is introduced to modify the pressure-loss formulation. Results indicate that higher viscosity, larger branch diameter, a higher manifold cross-sectional ratio, and a co-flow arrangement improve flow uniformity and prediction accuracy. Conversely, higher inlet velocities and counter-flow arrangements intensify vortex effects and increase prediction deviations. Least-squares fitting indicates that α ranges from 1.15 to 1.37. Implementation of the proposed correction reduces pressure-loss prediction errors to within 5%, demonstrating the method’s effectiveness and extending the applicability of fluid network theory to vortex-dominated flows.","source":"DOAJ","year":2026,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids11020052","url":"https://www.mdpi.com/2311-5521/11/2/52","is_open_access":true,"published_at":"","score":70},{"id":"ss_4aae8e2838a75b0f5a52b8cc533417ed9033ab4c","title":"Improving Senior High School Students’ Descriptive Essays Through Reflective Journaling Strategy","authors":[{"name":"Rehniel Jhun Omaya"}],"abstract":"Writing is a crucial skill in education, and among its various types, descriptive essays present unique challenges due to the need for vivid imagery, sensory details, and clear expression. This study determined the efficacy of reflective journaling in enhancing students’ descriptive writing in the areas of content, organization, grammar, mechanics, and vocabulary. An experimental two-group design was utilized with 77 respondents from the Grade 11 Science, Technology, Engineering, and Mathematics (STEM) strand. Data were collected through adapted and validated tests, along with survey questionnaires. The findings revealed that respondents in the control group performed fairly in content and organization but poorly in grammar, mechanics, and vocabulary, while the experimental group achieved very good results in content and organization, good results in grammar and mechanics, and fair results in vocabulary. Generally, the writing performance of the control group was described as poor, while that of the experimental group was described as good. A significant difference was found between the mean gains of the two groups in all areas, indicating higher performance in the experimental group. Moreover, motivation, classroom environment, grammar checker, and feedback system, as attributes influencing writing performance, were generally described as moderately positive in both groups. Thus, reflective journaling fostered critical self-assessment, enabling students to produce more vivid, detailed, and well-structured descriptive essays. It is recommended that reflective journal enhancement activities be utilized to improve descriptive writing skills further and sustain academic success in writing.","source":"Semantic Scholar","year":2026,"language":"en","subjects":null,"doi":"10.70838/pemj.520102","url":"https://www.semanticscholar.org/paper/4aae8e2838a75b0f5a52b8cc533417ed9033ab4c","is_open_access":true,"published_at":"","score":70},{"id":"ss_751df0df943128eb79f83f50eb097eb46d38a030","title":"Implementing Google Docs Collaboration to Improve Descriptive Writing Skills of Eleventh-Grade Students at SMA Lab School Untad Palu","authors":[{"name":"Syafira Naysilla Putri Atmoko"},{"name":"Sriati Usman"},{"name":"Budi Budi"},{"name":"Darmawan Darmawan"}],"abstract":"This research aims to investigate the effectiveness of Google Docs collaboration in improving descriptive text writing skills among eleventh-grade students at SMA Lab School Untad Palu. The research was conducted because many students faced challenges in writing descriptive text, particularly in mechanics (capitalization, punctuation, spelling), organization (logical structure and coherence), and content (idea development and relevance). A quantitative approach with a quasi-experimental pre-test and post-test control group design was employed. The sample consisted of two groups: the experimental group (n = 30), which was taught using Google Docs collaboration, and the control group (n = 29), which received conventional writing instruction. Students' writing skills were assessed using an analytic scoring rubric adapted from Oshima and Hogue (2006), focusing on three components: mechanics (5 points), organization (35 points), and content (20 points), totaling 60 points, converted to a 100-point scale. The descriptive statistics showed that the experimental group achieved notable improvement, with the mean score increasing from 43.67 in the pre-test to 83.43 in the post-test, whereas the control group showed minimal change from 28.48 to 79.31. The Mann-Whitney U test confirmed a significant difference between the groups, indicated by an Asymp. Sig. value of 0.000 \u003c 0.05. These findings demonstrate that Google Docs collaboration helps students provide real-time feedback, revise their work collaboratively, and organize ideas more effectively, resulting in improved writing performance in mechanics, organization, and content. Therefore, Google Docs is considered and effective digital tool for enhancing descriptive writing skills and is recommended for use in English writing classrooms aligned with the Merdeka Curriculum.","source":"Semantic Scholar","year":2026,"language":"en","subjects":null,"doi":"10.58421/gehu.v5i1.886","url":"https://www.semanticscholar.org/paper/751df0df943128eb79f83f50eb097eb46d38a030","is_open_access":true,"published_at":"","score":70},{"id":"ss_22c040cdfcbc0635dbff600a48b6461d867911d6","title":"Developing Undergraduate Critical Thinking Skills in Mechanics through the Use of Case Method-Based Teaching Materials with QR Code Videos","authors":[{"name":"A. Defianti"},{"name":"S. Sutarno"},{"name":"Henny Johan"}],"abstract":"This research aims to evaluate the effectiveness of using case method-based teaching materials with QR code videos on undergraduate students' critical thinking skills in mechanics. This research used a quasi-experimental method with a post-test-only control group design. A sample of 2 classes was taken using a purposive sampling technique. The experimental class used case method-based mechanics teaching materials and videos in QR codes, while the control class used print-outs of material summaries. Data collection was carried out through observation and critical thinking skills tests. Critical thinking skills test results data were analyzed using descriptive and inferential statistics. The t-test of two independent non-homogeneous samples is used to test the hypothesis of differences in means. The t-test results showed a difference in the average critical thinking skills scores of experimental and control class students with , greater than  at  (rounded up to 43). Based on these results, using case method-based mechanics teaching materials and videos in QR codes effectively develops students' critical thinking skills with an effectiveness level of 0.82, which means highly influential.","source":"Semantic Scholar","year":2025,"language":"en","subjects":null,"doi":"10.21009/1.11101","url":"https://www.semanticscholar.org/paper/22c040cdfcbc0635dbff600a48b6461d867911d6","pdf_url":"https://doi.org/10.21009/1.11101","is_open_access":true,"citations":2,"published_at":"","score":69.06},{"id":"crossref_10.1007/978-3-319-22449-7_11","title":"Experimental Mechanics for Graduate Students","authors":[{"name":"Christian Franck"}],"abstract":"","source":"CrossRef","year":2025,"language":"en","subjects":null,"doi":"10.1007/978-3-319-22449-7_11","url":"https://doi.org/10.1007/978-3-319-22449-7_11","is_open_access":true,"published_at":"","score":69},{"id":"doaj_10.3390/biomechanics5020023","title":"New Hip Adductor Isometric Strength Test on Force Platform Shows Good and Acceptable Intra-Test Reliability for Peak Force Measurement","authors":[{"name":"Pablo Merino-Muñoz"},{"name":"Felipe Hermosilla-Palma"},{"name":"Nicolás Gómez-Álvarez"},{"name":"Jorge Pérez-Contreras"},{"name":"Bianca Miarka"},{"name":"Carlos Gomes de Oliveira"},{"name":"Ciro José Brito"},{"name":"Luciano Luporini Menegaldo"},{"name":"Kristof Kipp"},{"name":"Esteban Aedo-Muñoz"}],"abstract":"\u003cb\u003eBackground/Objectives\u003c/b\u003e: Groin and hip injuries are common in sport, and muscle weakness has been identified as an intrinsic risk factor. So, analyzing the strength of the hip musculature becomes important. To date, there are no hip adductor isometric strength tests on force platforms. This study aims to analyze the intra-test reliability of a hip adductor strength test using force platforms. \u003cb\u003eMethods:\u003c/b\u003e The study sample comprised 13 male professional soccer players with an average age of 22.3 ± 3 years, body mass of 75.8 ± 5.4 kg, and height of 1.8 ± 0.1 m. Assessments were conducted on a uniaxial force platform. The variables analyzed are peak force (PF), rate of force development (RFD), and impulse. Intra-test reliability was evaluated using the coefficient of variation (CV), intraclass correlation coefficient (ICC), and Bland–Altman plots. \u003cb\u003eResults:\u003c/b\u003e Acceptable levels of reliability were identified solely for the variable of peak force, with CV values of D = 5.7% for the dominant profile and ND = 5.4% for the non-dominant profile. Furthermore, moderate and good relative reliability were observed in peak force for the dominant (ICC = 0.706) and non-dominant (ICC = 0.819) profiles, respectively. However, the remaining time-related variables, RFD and impulse, did not achieve acceptable levels of absolute reliability (CV \u003e 10%) and displayed poor to moderate relative reliability. \u003cb\u003eConclusions\u003c/b\u003e: In summary, PF during the hip adductor isometric strength test demonstrated acceptable absolute and commendable relative reliability. Conversely, the time-related variables, specifically RFD and impulse, yielded unsatisfactory absolute and relative reliability levels.","source":"DOAJ","year":2025,"language":"","subjects":["Mechanics of engineering. Applied mechanics","Descriptive and experimental mechanics"],"doi":"10.3390/biomechanics5020023","url":"https://www.mdpi.com/2673-7078/5/2/23","is_open_access":true,"published_at":"","score":69},{"id":"doaj_10.18502/acta.v63i4.20171","title":"Effects of Lower Extremity and Core Muscles Fatigue Protocols on Landing Mechanics and Performance in Female Athletes","authors":[{"name":"Razieh Hajizadeh"},{"name":"Hashem Piri"},{"name":"Nader Naserpour"},{"name":"Somayeh Mozafari"}],"abstract":"\nFatigue decreases muscle strength and functional capacity, disrupting neuromuscular coordination by impairing load control. This negatively impacts the kinetics and kinematics of the ankle, knee, and hip joints, resulting in reduced performance and an increased risk of injury, particularly to the anterior cruciate ligament (ACL). This study aimed to compare the effects of fatigue protocols for lower extremity and core muscles on landing mechanics and performance of female athletes. This study used a cross-sectional, comparative, pretest-posttest design with a control group. A total of 105 female athletes, aged 11 to 49, were selected via convenience and purposive sampling. Participants were divided into three groups: core muscle fatigue, lower extremity muscle fatigue, and a control group. Data were gathered using the Landing Error Scoring System (LESS), Y-Balance, and 45-degree trunk flexion tests. Data were analyzed using descriptive statistics, Shapiro-Wilk test, Levene's test, one-way ANCOVA, and the Bonferroni post hoc test. A P of 0.05 or lower was considered statistically significant. ANCOVA results showed significant differences among the groups for the LESS (P=0.001) and 45 ° trunk flexion test (P=0.001). There was no significant difference between the two experimental groups regarding the LESS (P=1.00). However, a significant difference was observed between the two experimental groups in the trunk flexion test (P=0.001). Fatigue had a greater effect size on landing mechanics (ηp²=0.209) than on the trunk flexion test (ηp²=0.143). However, no significant difference was observed between the groups regarding the Y-Balance Test (P=0.996). The study revealed that fatigue protocols targeting lower extremity and core muscles had a negative impact on kinematic parameters associated with ACL injuries during jump-landing in female athletes. Additionally, core muscle fatigue significantly impacted the 45º trunk flexion test, while lower extremity muscle fatigue had no significant effect on it.\n","source":"DOAJ","year":2025,"language":"","subjects":["Medicine (General)"],"doi":"10.18502/acta.v63i4.20171","url":"https://acta.tums.ac.ir/index.php/acta/article/view/11559","is_open_access":true,"published_at":"","score":69},{"id":"doaj_10.3390/fluids10070183","title":"High-Salinity Fluid Downslope Flow on Regolith Layer Examined by Laboratory Experiment: Implications for Recurring Slope Lineae on Martian Surfaces","authors":[{"name":"Yoshiki Tabuchi"},{"name":"Arata Kioka"},{"name":"Takeshi Tsuji"},{"name":"Yasuhiro Yamada"}],"abstract":"Numerous dark linear recurrent features called Recurring Slope Lineae (RSL) are observed on Martian surfaces, hypothesized as footprints of high-salinity liquid flow. This paper experimentally examined this “wet hypothesis” by analyzing the aspect ratios (length/width) of the flow traces on the granular material column to investigate how they vary with the granular material column, liquid and its flow rate, and inclination. While pure water produced low aspect ratios (\u003c1.0) on the Martian regolith simulant column, high-salinity fluid (CaCl\u003csub\u003e2\u003c/sub\u003e(aq)) traces exhibited significantly higher aspect ratios (\u003e4.0), suggesting that pure water alone is insufficient to explain RSL formulation. Furthermore, the aspect ratios of high-salinity fluid traces on Martian regolith simulants were among the highest observed across all studied granular materials with similar particle sizes, aligning closely with actual RSL observed on Martian slopes. The results further suggest that variable ARs of actual RSL at the given slope can partly be explained by variable flow rates of high-salinity flow as well as salinity (i.e., viscosity) of flow. The results can be attributed to the unique granular properties of Martian regolith, characterized by the lowest permeability and Beavers–Joseph slip coefficient among the studied granular materials. This distinctive microstructure surface promotes surface flow over Darcy flow within the regolith column, leading to a narrow and long-distance feature with high aspect ratios observed in Martian RSL. Thus, our findings support that high-salinity flows are the primary driver behind RSL formation on Mars. Our study suggests the presence of salts on the Martian surface and paves the way for further investigation into RSL formulation processes.","source":"DOAJ","year":2025,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids10070183","url":"https://www.mdpi.com/2311-5521/10/7/183","is_open_access":true,"published_at":"","score":69},{"id":"doaj_10.3390/fluids10010012","title":"On the Effect of Gas Content in Centrifugal Pump Operations with Non-Newtonian Slurries","authors":[{"name":"Nicola Zanini"},{"name":"Alessio Suman"},{"name":"Mattia Piovan"},{"name":"Michele Pinelli"}],"abstract":"Non-Newtonian fluids are widespread in industry, e.g., biomedical, food, and oil and gas, and their rheology plays a fundamental role in choosing the processing parameters. Centrifugal pumps are widely employed to ensure the displacement of a huge amount of fluids due to their robustness and reliability. Since the pump performance is usually provided by manufacturers only for water, the selection of a proper pump to handle non-Newtonian fluids may prove very tricky. On-field experiences in pump operations with non-Newtonian slurries report severe head and efficiency drops, especially in part-load operations, whose causes are still not fully understood. Several models are found in the literature to predict the performance of centrifugal pumps with this type of fluids, but a lack of reliability and generality emerges. In this work, an extensive experimental campaign is carried out with an on-purpose test bench to investigate the effect of non-Newtonian shear-thinning fluids on the performance of a small commercial centrifugal pump. A dedicated experimental campaign is conducted to study the causes of performance drops. The results allow to establish a relationship between head and efficiency drops with solid content in the mixture. Sudden performance drops and unstable operating points are detected in part-load operations and the most severe drops are detected with the higher kaolin content in the mixture. Performance drop investigation allows to ascribe performance drop to gas-locking phenomena. Finally, a critical analysis is proposed to relate the resulting performance with both fluids’ rheology and the gas fraction trapped in the fluid. The results here presented can be useful for future numerical validation and predicting performance models.","source":"DOAJ","year":2025,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids10010012","url":"https://www.mdpi.com/2311-5521/10/1/12","is_open_access":true,"published_at":"","score":69},{"id":"ss_121872faf232de15ccb0f2e867cdb972ed8ed2ef","title":"Using Facebook Messenger to Support Organization and Mechanics within Descriptive Essay Writing at Undergraduate Level: A Mixed Method Study","authors":[{"name":"Dr. Muhammad Rashid"},{"name":"Zara Mansoor"},{"name":"Naseem Waheed"}],"abstract":"This study investigated the effectiveness of Messenger-based text chatting in enhancing students' organization and mechanics within descriptive essay writing. A mixed-methods approach was utilized to explore Messenger's potential as a supplementary tool to traditional pedagogical practices. Sixty students were recruited through convenience sampling for participation. The experimental group (N=30) was engaged in an online text-based chatting via Messenger, while the control group (N=30) received only conventional lecture-based instruction. The findings of this mixed-methods study indicated that participants in the intervention group demonstrated better performance in descriptive essay writing compared to their counterparts. Additionally, the treatment group exhibited a positive attitude towards using Messenger, and text chatting facilitated online interaction that supported the acquisition of descriptive essay writing skills. These pedagogical implications underscore the potential of Messenger-based text chatting environments as valuable platforms for fostering active, collaborative learning in writing.","source":"Semantic Scholar","year":2025,"language":"en","subjects":null,"doi":"10.63075/gfykqh87","url":"https://www.semanticscholar.org/paper/121872faf232de15ccb0f2e867cdb972ed8ed2ef","is_open_access":true,"published_at":"","score":69},{"id":"ss_4ee8e0089d53f0c95737e2bf7905f314dc417ee6","title":"Effects of the Abdominal Draw-in Maneuver and Body Mechanics on Low Back Pain Relief in Nurses: A Quasi-Experimental Study","authors":[{"name":"Saeun Cheon"},{"name":"Seung-bin Park"},{"name":"Insoon Kang"}],"abstract":"Purpose: This study evaluated the effectiveness of an intervention combining the abdominal draw-in maneuver (ADIM) and body mechanics for nurses with chronic low back pain (LBP).Methods: A non-equivalent control group pretest-posttest design was used, with data collected from August 30 to December 29, 2023. Participants were nurses experiencing chronic LBP (≥3 months) from a university hospital. Participants were allocated by ward units, with the experimental group (n=30) enrolled first, followed by the control group (n=30). The experimental group received ADIM and body mechanics training, performed ADIM exercises three times weekly for 6 weeks, and received daily text reminders. Exercise adherence and body mechanics usage were monitored weekly. The control group received educational materials upon request after study completion. Outcomes included LBP intensity, LBP disability, lumbar flexibility, and body mechanics performance, analyzed using SPSS version 27.0 through descriptive statistics, the chi-squared test, the Fisher exact tests, the independent t-test, the Mann-Whitney U test, and analysis of covariance. Results: Compared to the control group, the experimental group showed significant reductions in LBP intensity (Z=4.65, p\u003c.001) and LBP disability (F=7.04, p=.010), as well as improvements in lumbar flexibility (t=6.15, p\u003c.001) and body mechanics performance (t=6.91, p\u003c.001). Conclusion: The intervention effectively alleviated LBP, reduced disability due to LBP, and improved lumbar flexibility and body mechanics performance. Thus, integrating ADIM with body mechanics may represent a practical and beneficial approach for reducing pain and enhancing functional outcomes among nurses experiencing chronic LBP in clinical settings.","source":"Semantic Scholar","year":2025,"language":"en","subjects":null,"doi":"10.7475/kjan.2025.0217","url":"https://www.semanticscholar.org/paper/4ee8e0089d53f0c95737e2bf7905f314dc417ee6","is_open_access":true,"published_at":"","score":69},{"id":"arxiv_2411.16583","title":"An FFT based chemo-mechanical framework with fracture: application to mesoscopic electrode degradation","authors":[{"name":"Gabriel Zarzoso"},{"name":"Eduardo Roque"},{"name":"Francisco Montero-Chacón"},{"name":"Javier Segurado"}],"abstract":"An FFT based method is proposed to simulate chemo-mechanical problems at the microscale including fracture, specially suited to predict crack formation during the intercalation process in batteries. The method involves three fields fully coupled, concentration, deformation gradient and damage. The mechanical problem is set in a finite strain framework and solved using Fourier Galerkin for non-linear problems in finite strains. The damage is modeled with Phase Field Fracture using a stress driving force. This problem is solved in Fourier space using conjugate gradient with an ad-hoc preconditioner. The chemical problem is modeled with the second Fick's law and physically based chemical potentials, is integrated using backward Euler and is solved by Newton-Raphson combined with a conjugate gradient solver. Buffer layers are introduced to break the periodicity and emulate Neumann boundary conditions for incoming mass flux. The framework is validated against Finite Elements the results of both methods are very close in all the cases. Finally, the framework is used to simulate the fracture of active particles of graphite during ion intercalation. The method is able to solve large problems at a reduced computational cost and reproduces the shape of the cracks observed in real particles.","source":"arXiv","year":2024,"language":"en","subjects":["cond-mat.mtrl-sci"],"url":"https://arxiv.org/abs/2411.16583","pdf_url":"https://arxiv.org/pdf/2411.16583","is_open_access":true,"published_at":"2024-11-25T17:12:55Z","score":68},{"id":"arxiv_2409.11763","title":"Experimental Learning of a Hyperelastic Behavior with a Physics-Augmented Neural Network","authors":[{"name":"Clément Jailin"},{"name":"Antoine Benady"},{"name":"Remi Legroux"},{"name":"Emmanuel Baranger"}],"abstract":"The recent development of Physics-Augmented Neural Networks (PANN) opens new opportunities for modeling material behaviors. These approaches have demonstrated their efficiency when trained on synthetic cases. This study aims to demonstrate the effectiveness of training PANN using real experimental data for modeling hyperelastic behavior. The approach involved two uni-axial experiments equipped with digital image correlation and force sensors. The tests achieved axial deformations exceeding 200% and presented non-linear responses. Twenty loading steps extracted from one experiment were used to train the PANN. The model architecture was optimized based on results from a validation dataset, utilizing equilibrium gap loss computed on six loading steps. Finally, 544 loading steps from the first experiment and 80 steps from a second independent experiment were used for testing purposes. The PANN model effectively captured the hyperelastic behavior across and beyond the training loads, showing superior performance compared to the standard Neo-Hookean model when assessed using various evaluation metrics. Training PANN with experimental mechanical data shows promising results, outperforming traditional modeling approaches.","source":"arXiv","year":2024,"language":"en","subjects":["physics.med-ph"],"doi":"10.1007/s11340-024-01106-5","url":"https://arxiv.org/abs/2409.11763","pdf_url":"https://arxiv.org/pdf/2409.11763","is_open_access":true,"published_at":"2024-09-18T07:42:57Z","score":68},{"id":"ss_48eaf91161037cc5ad6c6aa6d83c52a37dd5390c","title":"EFFECTS OF MIND-MAPPING AND OUTLINING AS PRE-WRITING TECHNIQUES ON DESCRIPTIVE PARAGRAPH WRITING OF EFL STUDENTS: A CASE AT TRA VINH UNIVERSITY, VIETNAM","authors":[{"name":"Nguyen Thi Huynh"},{"name":"Như"},{"name":"Thach Son Le"},{"name":"N. Phuong"},{"name":"Nam"}],"abstract":"The current study investigated the effects of pre-writing techniques, including mind-mapping and outlining on Vietnamese EFL learners’ descriptive paragraph writing at a university in Mekong Delta, Vietnam. Participants include 77 Vietnamese EFL students at Tra Vinh University. Data were collected through a test (pretest and post-test) and a questionnaire with 20 items. Quantitative data were analyzed by using SPSS. The findings showed that the students in experimental group  2 with outline condition had higher post-test scores than those in experimental group 1. Both mind-mapping and outlining achieved significant improvement in terms of grammar, mechanics, content, organization, and vocabulary; however, the development of outline condition is more sharply observed. In addition, the results from the questionnaire administered to two groups showed that students from the two conditions think positively about the role of the pre-writing techniques in their descriptive paragraph writing performance. These insights underscore the significance of employing pre-writing techniques as a valuable tool in enhancing writing skills. Finally, some recommendations for future researchers are also mentioned.","source":"Semantic Scholar","year":2024,"language":"en","subjects":null,"doi":"10.35382/tvujs.14.4.2024.94","url":"https://www.semanticscholar.org/paper/48eaf91161037cc5ad6c6aa6d83c52a37dd5390c","pdf_url":"https://doi.org/10.35382/tvujs.14.4.2024.94","is_open_access":true,"published_at":"","score":68},{"id":"ss_77a79b028e38f6c19f0675aa6b542711e04f349c","title":"Improving the English Writing Mechanics: A Study on Tenth-Grade Libyan Students in Malaysia Using the Dictogloss Technique","authors":[{"name":"Maruwan Alshireedi"},{"name":"Zurina Khairuddin"}],"abstract":"Writing mechanics are vital for gaining English language proficiency; however, certain students have faced difficulties with multiple domains, including spelling, punctuation, grammar, and sentence structure, particularly tenth-grade Libyan students in Malaysia. In this context, the dictogloss technique efficiently improves the English writing mechanics through a collaborative language-learning approach, involving students in recreating a sentence after listening, thus fostering active involvement and creative thinking. This article aims to evaluate the impact of writing mechanics on Libyan tenth-grade students' English Foreign Language (EFL) proficiency utilizing the dictogloss technique, applying a quantitative quasi-experimental design, and an independent t-test analysed through descriptive statistics using SPSS software version 25. This article utilized pre-test and post-test structures to collect data from 43 Libyan students across 5 Libyan secondary schools in Malaysia, divided into an experimental group that received writing instruction through the dictogloss technique over 8 sessions. In contrast, the control group adhered to the conventional grammar translation method. The result of dictogloss technique showed a significant improvement in the writing mechanics of the experimental group compared to the control group. The experimental and control groups had poor writing mechanics before the intervention, but the experimental group showed considerable improvement in punctuation and other mechanic domains after the intervention. This study helps academics find new ways to teach writing in international and diverse national settings to increase English language acquisition and academic success.","source":"Semantic Scholar","year":2024,"language":"en","subjects":null,"doi":"10.6007/ijarbss/v14-i11/23395","url":"https://www.semanticscholar.org/paper/77a79b028e38f6c19f0675aa6b542711e04f349c","is_open_access":true,"published_at":"","score":68},{"id":"doaj_10.3390/fluids8010020","title":"CFD Study of Thermal Stratification in a Scaled-Down, Toroidal Suppression Pool of Fukushima Daiichi Type BWR","authors":[{"name":"Sampath Bharadwaj Kota"},{"name":"Seik Mansoor Ali"},{"name":"Sreenivas Jayanti"}],"abstract":"During the 2011 nuclear catastrophe at Fukushima Daiichi, Unit 3 had a sharper increase in containment pressure than Unit 2, with thermal stratification of the suppression pool cited as one of the contributing factors. In the present work, the buoyancy-induced circulation consequent to steam condensation in a large, toroidal pool of water is studied using computational fluid dynamics (CFD) simulations with a view to understanding the role of important design parameters of the suppression pool system. The tunnelling phenomenon observed in the development of the thermal stratification process is delineated in terms of the establishment of a thermocline. The effects of the number of steam injection points and the cross-section of the pool on thermal stratification characteristics have been investigated through a number of case studies. In all the cases, the surface temperature, which is responsible for over-pressurization of the containment, is found to be significantly higher than the bulk pool temperature. Multiple injection points with the same overall steam flow rate are found to lead to higher surface temperatures due to a shortened circulation path. For the same volume of pool water, the simulations show that a deeper and narrower pool gives rise to significantly higher temperatures than a wider and shallower pool. This is attributed to the relatively deeper penetration of the buoyancy-induced circulation into the pool.","source":"DOAJ","year":2023,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids8010020","url":"https://www.mdpi.com/2311-5521/8/1/20","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.3390/fluids8070206","title":"Experimental Study on the Effect of the Angle of Attack on the Flow-Induced Vibration of a Harbor Seal’s Whisker","authors":[{"name":"Yuhan Wei"},{"name":"Chunning Ji"},{"name":"Dekui Yuan"},{"name":"Liqun Song"},{"name":"Dong Xu"}],"abstract":"A harbor seal’s whisker is able to sense the trailing vortices of marine organisms due to its unique three-dimensional wavy shape, which suppresses the vibrations caused by its own vortex-shedding, while exciting large-amplitude and synchronized vibrations in a wake flow. This provides insight into the development of whisker-inspired sensors, which have broad applications in the fields of ocean exploration and marine surveys. However, the harbor seal’s whisker may lose its vibration suppression ability when the angle of attack (AoA) of the incoming flow is large. In order to explore the flow-induced vibration (FIV) features of a harbor seal’s whisker at various angles of attack (\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmrow\u003e\u003cmi\u003eθ\u003c/mi\u003e\u003cmo\u003e=\u003c/mo\u003e\u003cmn\u003e0\u003c/mn\u003e\u003c/mrow\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e–\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsup\u003e\u003cmn\u003e90\u003c/mn\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e), this study experimentally investigates the effect of AoA on the vibration response of a whisker model in a wide range of reduced velocities (\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsub\u003e\u003cmi\u003eU\u003c/mi\u003e\u003cmi\u003er\u003c/mi\u003e\u003c/msub\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e = 3–32.2) and the Reynolds number, Re = 400–7000, in a circulating water flume. Meanwhile, for the sake of comparison, the FIV response of an elliptical cylinder with the same equivalent diameters is also presented. The results indicate that an increase in AoA enhances the vibration amplitude and expands the lock-in range for both the whisker model and the elliptical cylinder. The whisker model effectively suppresses vibration responses at \u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmrow\u003e\u003cmi\u003eθ\u003c/mi\u003e\u003cmo\u003e=\u003c/mo\u003e\u003cmsup\u003e\u003cmn\u003e0\u003c/mn\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/mrow\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e due to its unique three-dimensional wavy shape. However, when \u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmrow\u003e\u003cmi\u003eθ\u003c/mi\u003e\u003cmo\u003e≥\u003c/mo\u003e\u003cmsup\u003e\u003cmn\u003e30\u003c/mn\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/mrow\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e, the wavy surface structure gradually loses its suppression ability, resulting in large-amplitude vibration responses similar to those of the elliptical cylinder. For \u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmi\u003eθ\u003c/mi\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e = 30\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsup\u003e\u003cmrow\u003e\u003c/mrow\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e and 45\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsup\u003e\u003cmrow\u003e\u003c/mrow\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e, the vibration responses of the whisker model and the elliptical cylinder undergo three vibration regimes, i.e., vortex-induced vibration, transition response, and turbulent-induced vibration, with the increasing \u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsub\u003e\u003cmi\u003eU\u003c/mi\u003e\u003cmi\u003er\u003c/mi\u003e\u003c/msub\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e. However, at \u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmi\u003eθ\u003c/mi\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e = 60\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsup\u003e\u003cmrow\u003e\u003c/mrow\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e and 90\u003cinline-formula\u003e\u003cmath xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"\u003e\u003csemantics\u003e\u003cmsup\u003e\u003cmrow\u003e\u003c/mrow\u003e\u003cmo\u003e∘\u003c/mo\u003e\u003c/msup\u003e\u003c/semantics\u003e\u003c/math\u003e\u003c/inline-formula\u003e, the vortex-shedding gradually controls the FIV response, and only the vortex-induced vibration is observed.","source":"DOAJ","year":2023,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids8070206","url":"https://www.mdpi.com/2311-5521/8/7/206","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.3390/fluids8020056","title":"Non-Singular Burton–Miller Boundary Element Method for Acoustics","authors":[{"name":"Qiang Sun"},{"name":"Evert Klaseboer"}],"abstract":"The problem of non-unique solutions at fictitious frequencies that can appear in the boundary element method for external acoustic phenomena described by the Helmholtz equation is studied. We propose a method to fully desingularise in an analytical way the otherwise hyper-singular Burton–Miller framework, where the original boundary element method and its normal derivative are combined. The method considerably simplifies the use of higher-order elements, for example, quadratic curved surface elements. The concept is validated using the example of scattering on a rigid sphere and a rigid cube, and its robustness and effectiveness for external sound-wave problems are confirmed.","source":"DOAJ","year":2023,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids8020056","url":"https://www.mdpi.com/2311-5521/8/2/56","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.3390/fluids8010016","title":"The Role of Inertia in the Onset of Turbulence in a Vortex Filament","authors":[{"name":"Jean-Paul Caltagirone"}],"abstract":"The decay of the kinetic energy of a turbulent flow with time is not necessarily monotonic. This is revealed by simulations performed in the framework of discrete mechanics, where the kinetic energy can be transformed into pressure energy or vice versa; this persistent phenomenon is also observed for inviscid fluids. Different types of viscous vortex filaments generated by initial velocity conditions show that vortex stretching phenomena precede an abrupt onset of vortex bursting in high-shear regions. In all cases, the kinetic energy starts to grow by borrowing energy from the pressure before the transfer phase to the small turbulent structures. The result observed on the vortex filament is also found for the Taylor–Green vortex, which significantly differs from the previous results on this same case simulated from the Navier–Stokes equations. This disagreement is attributed to the physical model used, that of discrete mechanics, where the formulation is based on the conservation of acceleration. The reasons for this divergence are analyzed in depth; however, a spectral analysis allows finding the established laws on the decay of kinetic energy as a function of the wave number.","source":"DOAJ","year":2023,"language":"","subjects":["Thermodynamics","Descriptive and experimental mechanics"],"doi":"10.3390/fluids8010016","url":"https://www.mdpi.com/2311-5521/8/1/16","is_open_access":true,"published_at":"","score":67},{"id":"arxiv_2308.10500","title":"Quantum statistical mechanics from a Bohmian perspective","authors":[{"name":"Hrvoje Nikolic"}],"abstract":"We develop a general formulation of quantum statistical mechanics in terms of probability currents that satisfy continuity equations in the multi-particle position space, for closed and open systems with a fixed number of particles. The continuity equation for any closed or open system suggests a natural Bohmian interpretation in terms of microscopic particle trajectories, that make the same measurable predictions as standard quantum theory. The microscopic trajectories are not directly observable, but provide a general, simple and intuitive microscopic interpretation of macroscopic phenomena in quantum statistical mechanics. In particular, we discuss how various notions of entropy, proper and improper mixtures, and thermodynamics are understood from the Bohmian perspective.","source":"arXiv","year":2023,"language":"en","subjects":["quant-ph","cond-mat.stat-mech","hep-th"],"doi":"10.1016/j.physa.2024.129757","url":"https://arxiv.org/abs/2308.10500","pdf_url":"https://arxiv.org/pdf/2308.10500","is_open_access":true,"published_at":"2023-08-21T06:39:10Z","score":67}],"total":2605404,"page":1,"page_size":20,"sources":["CrossRef","DOAJ","arXiv","Semantic Scholar"],"query":"Descriptive and experimental mechanics"}