Abstract The operating temperature of photovoltaic (PV) modules is a key factor affecting electrical output because heat accumulation reduces voltage, power generation, and conversion efficiency. This study experimentally evaluated a passive thermal-management method using perforated aluminium composite panel (ACP) plates installed on the rear side of a 100 Wp polycrystalline PV module under outdoor conditions. Three perforation diameters, 20, 22.5, and 25 mm, were compared with an uncooled reference panel. Solar irradiance, PV surface temperature, lower-panel/ACP-plate temperature, voltage, current, output power, and efficiency were monitored during a 14-day outdoor campaign, with the detailed profile reported at 15 min intervals. At the peak irradiance of 1009 W/m², the 25 mm configuration recorded a PV panel surface temperature of 42.2 °C and a perforated ACP plate temperature of 38.5 °C, while producing 65.16 W at 16.25 V and 4.01 A, corresponding to an efficiency of 11.75%. The same configuration reached a maximum instantaneous efficiency of 13.29% and the highest mean performance ratio for the reported profile. These findings show that increasing perforation diameter enhanced rear-side heat removal and improved PV electrical performance without auxiliary cooling power.
In multi-story buildings, the ability to resist lateral forces is very important because the higher the structure, the greater the impact of earthquakes on its stability. To increase the stiffness of the structure, shear walls are used as a lateral force resisting system. Type 1 model is a structure without shear walls, so the load is only supported by columns and beams. Type 2 uses one shear wall on one side of the building, while Type 3 uses two shear walls on both sides of the building. The analysis results show that the largest P-Delta value occurs in Type 1 at 1.635 mm, whereas Type 2 decreases to 0.00056 mm, and Type 3 reaches 0.0001 mm. This indicates that the use of shear walls can reduce lateral deformation and improve the stability of water tower structures.
The research investigates pre-service teachers’ ability to create mathematical proofs through cooperative learning, as this skill becomes essential in university mathematics education. The research used a mixed-methods survey design to study 24 students who attended the Mathematics Education program at Universitas PGRI Palembang. Data was collected by a questionnaire, a mathematical proof test, and in-depth interviews. Data analysed descriptively. The results showed that most students were in the medium category of mathematical proof ability using a cooperative learning approach, with smaller proportions in the high and low categories. The investigation concluded that students with high mathematical proof ability demonstrated the ability to implement the five Mathematical Proof Indicators (IPMs) in constructing logical and systematic arguments and using mathematical representations appropriately. Students with moderate mathematical proof ability had difficulty with IPMc (third IPM) and IPMd (fourth IPM), while students with low mathematical proof ability had difficulty with almost all IPMs. The analysis of the investigation results indicates that strategies for conducting mathematical proofs require cooperative learning support to facilitate understanding of the concepts required for proofs and collaboration, and recommends its application in mathematics learning in higher education.
In academic and social contexts, generative artificial intelligence (GenAI) tools are increasingly common and are often promoted as aids for classroom learning. However, limited research has explored how Indonesian English education students use GenAI to support cross-cultural dialogue and meaning-making in everyday online interactions beyond formal classroom settings. This study employed a qualitative approach involving eight English Education students from the University of Palembang. Using semi-structured interviews and thematic analysis, the study explored how students use GenAI tools in cross-cultural meaning-making, their perceptions of the benefits of these tools, and the challenges they encounter when using GenAI for cross-cultural communication. The findings indicate that students use GenAI to clarify messages, refine their language to sound more natural and culturally appropriate, and obtain real-time support during cross-cultural online interactions. Participants also perceived GenAI as helpful in supporting their cross-cultural communication and language development. At the same time, they reported challenges including inaccurate or culturally insensitive outputs, increased dependence on the tool, and unintended changes in tone that sometimes led to misunderstandings. Keywords: Cross-cultural communication, meaning-making, Generative Artificial Intelligence (GenAI), Indonesian EFL students, intercultural dialogue
Spatial literacy is a vital math skill for students to learn during their three-dimensional geometry education. The two skills remain essential, yet most fifth-grade students struggle with spatial tasks. This challenge restricts their conceptual growth. The research examines fifth-grade students’ spatial literacy abilities and their error patterns to provide evidence for developing a Local Instructional Theory (LIT) on three-dimensional geometry. The research included 118 fifth-grade students (aged 10-11 years) from two public primary schools in Palembang who participated in a descriptive quantitative study with error analysis. The research data came from student performance on the spatial literacy diagnostic test and their error analysis records. The researchers applied descriptive statistics to determine average scores and establish performance levels for visualisation, reasoning, and communication skills. The researchers categorised student mistakes into four categories: procedural errors, conceptual errors, representational errors and communicative errors. The students produced results indicating significant differences in their performances. Students failed to perform basic procedural tasks, including spatial form comparison and application of formal notation, while they struggled with complex visualisation and the development of multiple-step spatial thinking and conceptual understanding. Students’ learning difficulties manifest as systematic errors, indicating that their challenges stem from complex, interconnected issues rather than random mistakes. The research results demonstrate that students need instruction which teaches them to develop their visualisation abilities, their reasoning skills, and explanatory competencies. The designs serve as an essential tool for uniting procedural fluency with conceptual understanding, leading to better spatial literacy in early geometry education.
