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The problems encountered are damage to the rubber wheel mount and universal/cross joints on the 90 m/hour capacity wood profile making machine, which can affect the uniformity and speed of wood profile making. Maintenance and repair planning aims to be able to create a maintenance and repair schedule for the 90 m/hour capacity wood profile making machine for the period 2026, estimate maintenance costs and the ratio of maintenance and repair costs to machine profits. The maintenance planning method includes collecting maintenance data from previous maintenance periods, reviewing the specifications of the wood profile making machine, estimating the age and price of components that are estimated to be damaged, estimating the cost and duration of dismantling and installing components that have been repaired in accordance with the provisions of the requirements for usable components or replacement spare parts, scheduling maintenance and repairs, estimating maintenance and repair costs for the period 2026, and determining the ratio of maintenance costs to profits. The planning results in the form of a maintenance-repair schedule for the period 2026; maintenance and repair costs in 2026, the ratio of maintenance costs to profits, and their implications indicate that the machine is still prospective and usable.

Gastric disease is a common health problem that can disrupt daily activities if not properly treated. To aid the initial diagnosis process, this study developed a web-based expert system capable of diagnosing various types of gastric disease based on the symptoms experienced by the user. This system uses the Dempster-Shafer method to address uncertainty in decision-making by combining a number of pieces of evidence in the form of symptoms to determine the level of confidence in a disease. The system was developed using the PHP programming language and a MySQL database and designed for easy browser access. Testing demonstrated that the system was able to provide fairly accurate diagnostic results that closely approximated the results of consultations with medical professionals. This system is expected to become an initial solution for the public in quickly and independently recognizing symptoms of gastric disease.

Waste from used Polypropylene (PP) and High Impact Polystyrene (HIPS) plastic is problematic in its management. The purpose of this research is to obtain the fatigue life of a mixture of used PP and HIPS plastics in its pure plastic. The research method is through the stages of mixing pure PP and 50% volume of used PP, pure HIPS and 50% volume of used HIPS, injection molding of R.R. Moore standard fatigue test specimens for pure PP, pure HIPS, pure PP + used PP, and pure HIPS + used HIPS, checking the straightness and smoothness of the molded specimen surface, fatigue testing with increasing serial loads, analysis of the bending stress curve (S) against fatigue life (N). The results showed that mixing used PP and used HIPS in pure plastic affected the fatigue life at the test speed (n)=2100 rpm for recycled PP was 9.84% shorter than pure PP, and at n=1600 rpm for recycled PP it was 9.32% shorter than pure PP, while at n=2100 rpm for recycled HIPS it was 4.45% shorter than pure HIPS, and at n=1600 rpm for recycled HIPS is 4.77% shorter than pure HIPS, while the fatigue life of pure PP is 1627704 cycles and the fatigue life of pure HIPS is 1291636 cycles or the fatigue life of pure HIPS is 20.65% shorter than pure PP, the implication of which is that the addition of used PP and used HIPS reduces the fatigue life to 9.84% for PP and 4.45% for HIPS.

Currently, patients experiencing early symptoms of skin disease caused by the exanthema virus are unable to immediately consult a dermatologist due to the high cost and limited time available for specialists in hospitals. Therefore, the author needs to develop an expert system application that can address this issue. Through this application, users can consult with the system, much like an expert, to diagnose their symptoms and find solutions to their problems. This expert system is designed to provide answers based on whether the symptoms are correct or not, or to provide several recommended answer choices based on the symptoms. To diagnose skin disease caused by the exanthema virus, the author used the Case-Based Reasoning method. The CBR method is a weighting technique that compares new cases with previous cases. The diagnosis is based on data provided by the patient and expert, which is then analyzed using case-based reasoning and stored as a knowledge database in the expert system. Therefore, this expert system can help identify solutions for problems experienced by patients suffering from skin disease caused by the Exanthema Virus.

Tulungagung Regency has the potential for culinary tourism that can be developed, one of which is traditional culinary. Although the Tulungagung Regency Government has presented a "Halal Culinary Area" and a "Pinka Culinary Tourism Area", the area has not fully provided an interesting visual and functional experience. Therefore, it is necessary to design a space that facilitates traditional culinary MSMEs as well as an educational and recreational place. This design carries the theme of contemporary tropical architecture by considering local climatic conditions, through the application of wide openings, cross ventilation, wide trellises, and the use of natural materials, as well as expressive styles with the shape of a rooster roof and the basic shape of an elliptical building as a symbol of adaptation to climate change and the economy in the business environment. The facilities in this design include traditional restaurants, educational bales, wiyata offices, prayer rooms, playgrounds and other supporting facilities that can attract the interest of the community and introduce traditional Tulungagung culinary.

The development of sustainable tourism facilities is one of the important efforts in increasing the attractiveness of destinations while preserving the environment. This study aims to analyze the implementation of ecological concepts in the development of glamping facilities in the Pearl Beach tourist area. The method used is a descriptive qualitative approach, with data collection through field observations, interviews with managers and tourists, and literature studies related to ecotourism principles and sustainable design. The results of the study show that the application of ecological concepts in glamping facilities in Mutiara Beach includes the use of environmentally friendly materials, integrated waste management, the application of energy efficiency, and designs that integrate the natural landscape without damaging the coastal ecosystem. The application of this concept not only improves the comfort and experience of tourists, but also contributes to increasing environmental awareness and strengthening the positive image of tourist destinations. In addition, this ecologically-conceptual glamping development model is expected to be a reference for the development of sustainable tourism facilities in other coastal areas, which prioritizes nature preservation and the welfare of local communities.

A research about study of sandstone slope stability using the Bishop Simplified method in Uu Samarinda has been conducted. This study was conducted to analyze the rebound number values of sandstone slopes, evaluate their stability level, and calculate the safety factor using the Bishop method. The results showed that the rebound number values were 22.34 at point 1, 19.83 at point 2, and 18.07 at point 3. The Uniaxial Compressive Strength (UCS) values at the observation points were 1.90 MPa, 1.62 MPa, and 2.21 MPa, respectively. Geological Strength Index (GSI) evaluation indicated a rating of 80–85, demonstrating intact/massive rock structure, fresh and unweathered rock surfaces, and very good rock quality. Based on the Bishop method analysis, the slope factor of safety in 6.525  with a probability of failure is 0.000%, indicating that the sandstone slope in Ulu Samarinda is highly stable even under external pressures such as heavy rainfall or minor earthquakes. This study provides crucial information on the mechanical characteristics and stability of sandstone slopes in ulu Samarinda, which can serve as a reference for technical planning, geotechnical risk mitigation, and the sustainable development of safe areas.

This study aims to determine the relationship between learning motivation and learning outcomes in SMAW welding engineering among eleventh-grade students at SMKN 2 Solok. This research employed a quantitative method with a correlational approach. The population consisted of all students from classes XI TPM 1 and XI TPM 2, totaling 51 students, using a total sampling technique. Learning motivation data were collected through a validated and reliable questionnaire, while learning outcome data were obtained from post-test scores in the SMAW welding subject. Data were analyzed using the Pearson Product Moment correlation test with the assistance of SPSS software. The results showed a correlation coefficient of r = 0.783 with a significance value of 0.000 < 0.01, indicating a strong, positive, and statistically significant relationship between learning motivation and students’ learning outcomes. These findings suggest that higher learning motivation leads to better learning outcomes in SMAW welding engineering. Therefore, learning motivation plays an important role in improving students’ academic performance. This study is expected to provide useful insights for teachers and schools in developing instructional strategies that enhance students’ motivation and learning outcomes.

During the coal stockpiling process, the quality of coal may increase or decrease due to direct exposure to open environmental conditions, which can lead to changes in its characteristics. The longer the coal is stored in an open area, the more it undergoes changes caused by rainfall, heat, and air exposure, resulting in an increase in moisture content and ash content, while the calorific value decreases. Therefore, this research was conducted to determine the optimal coal stockpiling duration at the ROM coal stockpile to ensure that the calorific value does not significantly decrease. Coal sampling was carried out every two days from the initial time of stockpiling. After a two-month stockpiling period, the final coal quality results showed a total moisture of 13.89% (ar), inherent moisture of 15.95% (ad), ash content of 4.59% (ad), volatile matter of 40.3% (ad), and fixed carbon of 39.16% (ad). Based on these results, it can be concluded that the recommended storage duration for MCV-HS type coal at the ROM coal stockpile is 154 days. The laboratory analysis results obtained during the research indicate that the longer the coal is stored, the higher the moisture content and ash content become, while the calorific value continues to decrease. This occurs due to water absorption and oxidation reactions that take place during the coal storage period in the ROM coal stockpile.

This research investigates the Peak Particle Velocity (PPV) resulting from blasting operations at Pit Pinang, PT Bukit Baiduri Energi, employing two prediction approaches: Non-Linear Geometric Regression and the USBM Oriard’s Formula. Ground vibration measurements were recorded over a one-month period, from October 9 to November 8, 2025. The findings indicate that the non-linear regression model achieves a higher predictive accuracy of 78.62%, outperforming the USBM Oriard’s Formula, which reaches 68.2%. Variations between the observed and estimated PPV values were affected by factors such as the location of geophones, differences in explosive charges, and alterations in borehole depths. In addition, the study evaluates optimal explosive charge recommendations in accordance with SNI 7571:2010 standards to mitigate potential structural damage in surrounding areas. By highlighting these predictive discrepancies and providing practical guidance on charge management, the research offers valuable insights for improving blasting safety and minimizing vibration impacts on nearby infrastructure. The comparison of methods emphasizes the importance of selecting appropriate prediction models to ensure both operational efficiency and environmental safety.

This study analyzes customer attrition in barbershops through the application of the 4P marketing mix, which includes Product, Price, Place, and Promotion. The research was conducted using a questionnaire distributed to 30 barbershop customers, which aimed to assess their level of satisfaction regarding each element of the marketing mix. The findings revealed that while customers were generally satisfied with the quality of the haircuts and the cleanliness of the tools, there was an important demand for improvement in the quality and variety of additional products offered. The pricing strategy was considered affordable by most customers; however, some expressed dissatisfaction, indicating the need for better communication regarding the value of the services provided. Demographic analysis showed that the majority of respondents were young adults aged 18-25, highlighting a specific target market for barbershops. Overall, this study emphasizes the importance of effectively implementing the marketing mix to improve customer retention and satisfaction in the barbershop industry.

The Special Region of Yogyakarta (DIY) is characterized by high seismic activity due to its proximity to the subduction zone and the presence of active fault systems, particularly the Opak Fault. The 2006 Yogyakarta earthquake revealed significant vulnerability in local building structures and highlighted the complex geological conditions governing seismic wave propagation. This study aims to calculate and map the Peak Ground Acceleration (PGA) distribution in Prambanan District, Klaten Regency—one of the areas closest to the 2006 earthquake source. PGA values were estimated using the McGuire attenuation relationship, based on a moment magnitude of Mw 6.3 and the hypocentral distance to 88 observation points distributed at approximately 900-meter intervals. The resulting PGA map indicates values ranging from 26.7 to 31.7 gal, with a clear spatial trend showing increasing intensity from the northern to the southern parts of the study area. Higher PGA values occur in regions near the Opak Fault and in areas dominated by unconsolidated volcanic deposits of the young Merapi formation. These loose sediments amplify seismic waves, resulting in stronger ground motion compared to areas composed of more compact sedimentary rocks. The spatial pattern of PGA corresponds well with the distribution of structural damage recorded during the 2006 earthquake. The findings emphasize the significant role of local geology and fault proximity in shaping seismic hazard levels. Consequently, this study provides essential insights for disaster mitigation strategies, land-use planning, and structural vulnerability assessment within the Prambanan area.

Coal quality must be controlled from the pit area to the ROM stockpile to ensure compliance with market specifications. However, hauling and stockpiling processes often lead to changes in coal characteristics. This study aims to analyze variations in proximate parameters between coal from Pit B1 and ROM Stockpile Km4 at PT Trisensa Mineral Utama and to identify factors contributing to these changes. The methodology includes field sampling at both locations, sample preparation based on ASTM standards, and laboratory testing of inherent moisture, residual moisture, ash content, volatile matter, and fixed carbon. The results indicate that coal undergoes quality changes after being stored in the stockpile, marked by a decrease in inherent moisture of 2.54% (from 17.64% to 15.10%), a decrease in residual moisture of 1.42% (from 17.17% to 15.75%), a slight reduction in ash content of 0.16%, a decline in volatile matter of 0.28%, and a reduction in fixed carbon of 0.18%. These changes are influenced by field conditions, material contamination during mining, rainfall, coal porosity, and handling activities at the stockpile. The findings highlight the need for improved sampling management, better surface water control, and stricter material handling procedures to minimize coal quality degradation.

This study examines human facial proportions through an anthropometric approach based on the Phi value of the Golden Ratio (φ = 1.618) to understand the relationship between mathematical proportionality and visual aesthetics. The analysis focuses on two public figures, Jin and V of BTS, who are widely recognized as visual representatives within contemporary popular culture. Using two-dimensional anthropometric measurements, four primary facial aspects were evaluated: the facial length-to-width ratio, the proportional relationship between the forehead, nose, and chin, the eye–mouth–chin vertical proportion, and the alignment of eye width with interocular distance. Each measurement was compared to the Phi value to assess its degree of proportional conformity. The findings indicate that most facial ratios observed in both Jin and V closely approximate or match the Golden Ratio, with V exhibiting the highest precision in vertical proportional measurements, while Jin demonstrates more consistent overall proportional stability across multiple facial components. These results support the use of the Phi Golden Ratio as a mathematical indicator in assessing facial proportion and aesthetic harmony. Nevertheless, the study acknowledges that visual aesthetics remain inherently subjective and are influenced by cultural context and individual perception. Thus, anthropometric analysis based on the Golden Ratio can serve as a complementary tool in understanding human facial aesthetics.  

Mine disposal materials such as tailings, overburden, and waste rocks are critical components in mining operations that require comprehensive understanding of their geotechnical properties to ensure stability and safety of storage facilities. This literature review aims to analyze the role of particle gradation and mineralogical composition in determining shear strength and compressibility of mine disposal materials, with particular focus on nickel mining. A sistematic literature review method was employed by analyzing 30 scientific publications from 2019-2025 obtained from various academic databases. The review findings indicate that particle size distribution (gradation) has significant influence on shear strength and compressibility, where materials with coarser gradation and higher coefficient of uniformity (Cu) exhibit greater shear strength and lower compressibility. Mineralogy, particularly clay mineral content, increases cohesion and microporosity but also increases compressibility under loose conditions. Studies on nickel mine waste demonstrate that ferronickel slag possesses favorable drainage characteristics suitable for rockfill material, while tailings require strict gradation control. In conclusion, comprehensive characterization integrating gradation parameters (Cu, Cc, D50) with mineralogical analysis (XRD, XRF) is essential for predicting mechanical behavior of mine disposal materials and designing safe storage facilities.

The development of smart cities has become a strategic priority for local governments seeking to enhance citizens’ quality of life, strengthen sustainable development, and improve public space management. Kambang Iwak Park in Palembang represents one of the city’s major urban green spaces that has undergone significant revitalization and serves as a case study for smart city implementation in public areas. This study analyzes the application of Cohen’s six smart city dimensions—Smart People, Smart Living, Smart Government, Smart Economy, Smart Mobility, and Smart Environment—and their relationship with Carmona’s six urban design dimensions. This qualitative–descriptive research utilizes visual observations, historical data, and facility documentation extracted from the provided presentation. The findings indicate that Kambang Iwak Park effectively integrates several smart city dimensions, particularly Smart Living, Smart Environment, and Smart Mobility. Nonetheless, issues such as irregular parking, insufficient smart services, and poorly organized street vendors remain challenges. The study concludes that integrating smart city principles with urban design concepts enhances public space quality and supports sustainable urban development in Palembang.

The oil and gas industry plays a crucial role in meeting global energy needs, with crude oil from production wells being the primary product of upstream operations. Prior to further processing, crude oil requires pretreatment at the production site, one of the key stages being phase separation using a flash separator. This study examines the effect of variations in cooling temperature on the performance of liquid phase separation and energy requirements in the flash separation process of light hydrocarbons. The analysis was conducted through process simulation using Aspen HYSYS version 14.2 with the Peng Robinson property package. The feed stream had a mass rate of 10,000 kg per hour, a temperature of 50°F, and atmospheric pressure, with compositions of ethane, propane, isobutane, and normal butane. The process configuration included compression, cooling, and phase separation in a flash separator at a constant pressure of 50 psia. Variations in cooling temperature were applied at 20, 10, and 0°C. The simulation results indicated a thermodynamic critical point at 10°C. At 20°C, no liquid phase was formed, while at 10°C, significant liquid yield was obtained with moderate energy consumption. Lowering the temperature to 0°C dramatically increases liquid recovery, but the cooling energy requirement also increases sharply. Sensitivity analysis confirms a strong inverse relationship between temperature and condensation yield, as well as a surge in energy consumption at low temperatures. The optimal operating condition is set at 10°C, providing a balance between separation efficiency and energy efficiency in accordance with sustainable manufacturing principles.

This study aims to analyze the level of flood hazard in Baturaja Barat District, Ogan Komering Ulu Regency, by applying a spatial approach using Geographic Information Systems (GIS) through the overlay method. The analysis was carried out by integrating six main physical parameters, namely rainfall, land use, elevation, slope, river density, and soil type. Each parameter was assigned a score and weight according to its influence on flood potential and subsequently processed spatially to produce a flood hazard map. The results indicate that the Baturaja Barat District area is classified into three hazard levels: low (3.25%), moderate (70.64%), and high (25.84%). Areas with high hazard levels are predominantly characterized by densely populated settlements situated at low elevations and in close proximity to river networks, particularly in Tanjung Karang, Air Gading, Talang Jawa, Karang Agung, and surrounding villages. These findings highlight that land-use changes, topographic conditions, and the distribution of river networks play significant roles in increasing flood risk. The results of this study are expected to serve as a foundation for spatial planning, the strengthening of disaster mitigation policies, and the enhancement of community preparedness against flood hazards in the region.

The stability of slopes in open-pit coal mining in Indonesia is significantly influenced by geological faults, which are a major factor causing slope failures. This study aims to examine the impact of faults on slope stability by conducting a systematic literature review of 25 scientific publications from 2018 to 2025. The results indicate that faults and fault zones consistently reduce rock mass integrity through several mechanisms, including stress concentration in weak zones, the formation of preferential sliding surfaces, amplification of hydro-mechanical effects from groundwater and rainfall, and the reduction of rock strength parameters. Case studies in Kalimantan and Sumatra confirm these mechanisms with slope failures aligning with fault orientations. Kinematic and numerical analyses using the Limit Equilibrium Method (LEM), Finite Element Method (FEM), and Distinct Element Method (DEM) show a reduction in the safety factor (SF) by up to 36% on slopes affected by faults. Practical recommendations include continuous monitoring using Slope Stability Radar (SSR), optimization of slope geometry with angles < 18° in fault zones, groundwater control, reinforcement with anchors and bolting, and UAV-based discontinuity mapping for hazard zoning. This study concludes that managing slopes in fault zones requires an integrated approach combining detailed geological investigation, multi-method numerical analysis, real-time monitoring, and specific mitigation design.

This study analyzes failures in the bending machine at PT. XYZ and determines maintenance priorities to reduce downtime and improve production efficiency. The company often faces repeated breakdowns, especially in hydraulic and control components, which negatively impact productivity. To address these issues, the research applies Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA). The study employs a descriptive qualitative approach using downtime and repair data from September 2024 to February 2025. FMEA was conducted to identify failure modes, effects, and causes, and to calculate the Risk Priority Number (RPN) as a basis for prioritization. FTA was then applied to trace root causes by mapping logical relationships among contributing factors leading to the top event. Recommendations were formulated with the 5W+1H method to propose preventive maintenance actions. The results indicate that the hydraulic valve is the most critical component, with an RPN value of 504 due to oil contamination. The main causes include damaged filters, improper oil usage, and lack of a cooling system. The hydraulic cylinder seal and back gauge were also found to contribute significantly to machine failures. FTA analysis revealed root causes such as inadequate maintenance procedures, unsuitable materials, and insufficient inspections. The proposed improvements involve regular replacement of oil filters, structured lubrication schedules, installation of oil coolers, and technician training to strengthen compliance with standard procedures. Overall, the integration of FMEA and FTA provides a systematic approach to identify critical components and root causes, enabling PT. XYZ to implement preventive strategies that minimize failures, reduce downtime, and improve bending machine performance sustainably.