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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.

The demand for lightweight materials with high mechanical strength has driven the development of aluminum alloys, particularly Al-Mg-Si, through deformation processes such as cold rolling. This study aims to analyze the effect of varying degrees of cold rolling deformation on the grain aspect ratio and macrohardness of homogenized Al-Mg-Si alloys. Deformation was applied at three thickness reduction levels—5%, 10%, and 20%—followed by microstructural characterization using optical microscopy and macrohardness testing in accordance with ASTM E-18 standards. The results show that increasing deformation levels lead to elongated grain morphology, with the grain aspect ratio rising from 1.16 to 2.07 and macrohardness increasing from 46.64 HRE to 62 HRE. The emergence of slip lines and grain flattening indicates the occurrence of intense plastic deformation, while work hardening results from dislocation accumulation that impedes further slip motion. These findings confirm a strong correlation between microstructural evolution and mechanical property enhancement in cold-deformed Al-Mg-Si alloys. This research contributes to the optimization of cold rolling parameters to produce engineering materials with a desirable balance of strength, formability, and fatigue resistance for applications in the mining and heavy manufacturing industries.

Overburden removal is a critical phase in coal mining operations, as it directly affects production continuity and operational efficiency. However, production realization often deviates from the mine plan due to various operational constraints. This study, conducted at Pit K1 Mahakam of PT. Insani Baraperkasa, evaluates the causes of underachievement in overburden stripping targets using the Six Big Losses framework, which classifies inefficiencies into Breakdown Losses, Setup and Adjustment Losses, Idling and Minor Stops, Reduced Speed Losses, Process Defect Losses, and Reduced Yield Losses. The analysis revealed that the dominant losses were Reduced Speed Losses (26%) and Setup and Adjustment Losses (10%), primarily caused by disposal congestion, shift changes, and repairs at the loading and disposal areas. Minor contributions were found from idling (3%), production losses (5%), while breakdown losses showed negligible impact. These factors led to increased standby time and reduced equipment cycle effectiveness. Improvement strategies are recommended through optimized disposal allocation, reduction of waiting time, and stricter control of external operational disruptions to enhance stripping efficiency and achieve production targets.

This study aims to analyze the effect of blasting geometry on drilling and blasting costs in mining operations at PT Unggul Dinamika Utama, Kutai Timur Regency, East Kalimantan Province. The research focuses on comparing two operational areas, namely PIT Tempudo 6 and PIT East, which apply different blasting geometries: a burden of 7 m and spacing of 8 m at PIT Tempudo 6, and a burden of 8 m and spacing of 9 m at PIT East. The research method involved collecting primary data from actual field drilling and blasting activities, as well as secondary data from the company. The parameters analyzed included blasting geometry, explosive consumption, and operational costs of drilling and blasting. The results show that the total drilling cost at PIT Tempudo 6 was Rp. 215,689,696, while at PIT East it was Rp. 162,177,899. The total blasting cost at PIT Tempudo 6 reached Rp. 3,023,066,977.60, while at PIT East it was Rp. 1,780,839,602.80. Thus, the total operational cost of blasting activities at PIT Tempudo 6 amounted to Rp. 3,238,756,673.60, and at PIT East amounted to Rp. 1,943,017,501.80. It can be concluded that differences in blasting geometry significantly affect operational cost efficiency. Larger burden and spacing values lead to more efficient costs by reducing the number of drill holes and explosive consumption per blasted rock volume.

The success of a production process is highly dependent on effective quality control. In this study, the focus is directed toward Pc Slab Type A products manufactured by PT. XYZ, a precast concrete company for highways and building structures. The evaluation emphasizes efforts to reduce chipping defects. Improvement priorities were determined using the Failure Mode and Effect Analysis (FMEA) method based on the Risk Priority Number (RPN). Root Cause Analysis (RCA) was applied to identify the underlying problems. The analysis revealed that the dominant factor comes from the human aspect, with the highest RPN value of 294, namely the lack of regular supervision. Additional contributing factors include improper mold opening methods (RPN 216), inconsistent worker performance (RPN 175), inter-division transfers (RPN 125), and delayed maintenance schedules (RPN 120). All causes were elaborated using the 5W+1H approach, covering reasons, locations, timing, implementation, and proposed corrective actions.

This research addresses the low student learning outcomes and the lack of facilitation of 4C competencies (Critical Thinking, Collaboration, Communication, and Creativity) in the Industrial Machine Electrical Systems (SKMI) subject for Grade XI TMI 1 students at SMK Negeri 1 Pariaman. The teacher-centered learning approach has led to passive student participation, low critical thinking, varying academic abilities, and difficulty in connecting theoretical concepts to real-life applications. The aim of this study is to improve students' 4C competencies and learning outcomes through the implementation of the Team Assisted Individualization (TAI) cooperative learning model. Using Classroom Action Research (CAR) based on the Kemmis and McTaggart model, the study was conducted in three cycles: planning, implementation, observation, and reflection. The subjects were 30 students from Grade XI TMI 1. Data collection included learning outcome tests and 4C competency observation sheets, with descriptive and quantitative data analysis. The results showed significant improvements: classical mastery increased from 27% to 90%, average learning scores rose from 67 to 81, and 4C competency mastery improved from 34% (low) to 82% (high). The study concludes that the TAI model effectively enhances both 4C competencies and learning outcomes in SKMI at SMK Negeri 1 Pariaman.

Rock stability and service life in geotechnical and mining engineering are highly dependent on the rock's mechanical and physical parameters, where the variation in sandstone grain size is a crucial intrinsic factor. This study aims to comprehensively analyze the correlation between sandstone grain size with uniaxial compressive strength (UCS) and resistance to weathering (Slake Durability Index) in samples taken from the Balikpapan and Pulau Balang Formations in the Samarinda area, East Kalimantan. The research methodology involved a series of standard laboratory tests, including rock physical properties analysis, grain size distribution analysis, UCS testing, and slake durability testing through three cycles. The test results show a significant correlation: sandstone with finer grain sizes and higher density consistently demonstrates greater UCS values and a higher Durability Index, indicating superior mechanical and physical resistance. Specifically, the Pulau Balang Formation exhibits a more compact structure and finer grain size, resulting in better durability values compared to the Balikpapan Formation. These findings are important as a geomechanical data basis for slope design planning, rock mass stability analysis, and material selection in infrastructure projects or mining operations involving both formations.

Students’ learning outcomes are influenced by various internal and external factors, one of which is learning motivation. This study aims to analyze the relationship between learning motivation and learning outcomes in the Creative Product and Entrepreneurship (PKK) subject among 11th-grade students at SMK Semen Padang. The research employed a quantitative approach with a correlational design. The population consisted of 47 students, all of whom were included as samples using the total sampling technique. Data on learning motivation were collected through a questionnaire, while learning outcomes were obtained from official school records. Data analysis was carried out using descriptive statistics and the Pearson Product Moment correlation test. The results revealed a positive and significant relationship between learning motivation and learning outcomes (r = 0.547 > 0.288; p = 0.000 < 0.05), with a contribution of 29.9%. These findings indicate that the higher the students’ learning motivation, the better their academic performance. This study highlights the crucial role of motivation as a determinant of academic achievement and suggests that teachers should foster students’ learning enthusiasm through engaging and interactive teaching strategies.

This research discusses the development of a school Geographic Information System (GIS) based on a microservice architecture to simplify access and management of school data. The background of this study is the need for an efficient and well-organized school data management system that can present school information interactively to the public. The purpose of this research is to build a system capable of displaying school locations and providing data management features for teachers, students, and school accreditation through CRUD (Create, Read, Update, Delete) operations. The development method includes database design, API creation for each microservice, data integration through an interactive map interface using Leaflet, and system testing using the Black Box Testing method. The test results show that all system features function properly and meet user requirements. The implementation of microservice architecture allows the system to be more flexible, easily updated, and well distributed among services. With this system, the public can access school information quickly and accurately, while schools can manage their data more effectively.

The purpose of this study was to determine the effect of pulley angle variations of 13.5ᵒ and 14ᵒ and roller weight variations of 12 g, 14 g, and 16 g on the torque of a 150 cm3 automatic motorcycle. The method with a quantitative approach the method used is the experimental method. For the sample of this research is a type of pulley and 3 types of rollers with different slopes and weights where the angle varies to test the 150 cm3 matic motorcycle torque used. From the results of this study results in a value where the Fcount value is greater than the Ftable means that the null hypothesis (H02) is rejected and the alternative hypothesis (H22) is accepted or the mass of the roller has an influence on torque, the Fcount value is greater than the Ftable means that the hypothesis (H01) is rejected and the alternative hypothesis (H11) is accepted or the mass of the roller has an influence on torque, and that the interaction between pulley angle and roller mass does not affect, and the Ftable value is lower than the Fcount value that the hypothesis (H03) is accepted and the alternative hypothesis (H33) is rejected, roller mass affects torque.

In the#world of work assessment, it is very important, every organization will develop the best strategy to be able to compete. Especially in improving employee performance. The background to good employee performance is the ability to adapt, having skills that are relevant to the job, and the willingness to continue learning and developing. Thus, companies can achieve brand goals more effectively and efficiently. Similar to other companies, PT. Hilfic also carries out performance assessments of its employees. In this research, employee performance assessment uses a strategy based on Key Performance Indicators (KPI). The aim of this research is to identify factors that influence employee performance, such as motivation, competence, work environment, etc. The method used uses qualitative methods. The research results show that there is a positive and significant influence on employee performance, especially on quality and quantity after the company implemented Key Performance Indicators (KPI) as an assessment of its performance.

Employee training and development is an activity that aims to improve employee competence, knowledge and attitudes in achieving achievement. This training is provided to both new employees and existing employees who still need training and retraining. In practice, training is a short-term development process that uses a structured and organized operating system, with the main aim of improving employee performance and opening up career opportunities. Employees need to have sufficient skills and knowledge, and one way to meet these needs is through training programs designed to improve the quality of human resources. In this way, employees can achieve their desires and ultimately get the expected results.  

Air pollution and oil reserves are two major issues in the technological development of the automotive industry. Air pollution is caused by gases from burning fossil fuel vehicles. In 2018-2019 Indonesia experienced a drastic decrease in petroleum resources by 49.8%. To overcome this problem, many researchers have conducted research on electric vehicles, including electric bicycles. This study aims to determine the effect of distance and load on BLDC motor power consumption on a prototype e-bomber electric bicycle designed for all terrains such as rocky, sandy, and muddy, and has a large battery capacity, low power consumption, and an electric motor with good speed and torque. This research uses a pseudo-experimental method with a quantitative approach. Tests were carried out on e-bomber electric bicycles with distances of 3 km, 5 km, and 8 km and loads of 60 kg, 70 kg, and 80 kg with a speed of 25 km / h. The results showed that there was an influence of distance and load on the e-bomber electric bicycle. The results showed that there was an effect of distance and load on BLDC motor power consumption with the results of graph analysis and two-way ANOVA tests conducted and the lowest average power consumption of 500 watts at a distance of 3 km and a load of 60 kg, while the highest average power consumption was 522.5 watts at a distance of 8 km and a load of 80 kg.

Work safety is always a priority, especially in the mining world which has a high potential for danger. Therefore, there are many regulations that must be obeyed, including the prohibition of smoking in the cabin of the Dump Truck unit. This study aims to design a cigarette smoke detector in the cab of a dump truck as a form of warning to drivers who violate the ban on smoking in the cab. The method used in this research is a quantitative method by conducting experiments. The research conducted is to analyze the effect of smoke thickness levels (20%, 40%, and 60%) on different sensor types (MQ-4 and MQ-7). The expected result is the effect of smoke thickness variation on the response time of different sensors.

The coal blending process conducted by PT. Bukit Baiduri Energi (PT. BBE) aims to achieve coal quality specifications that align with customer requirements. PT. BBE possesses multiple coal seams with varying quality characteristics, necessitating a carefully planned blending system with precise proportions to produce coal products that meet market demands. The objectives of this study are: to plan the quantity and quality parameters for coal blending, to evaluate the actual outcomes of coal blending in terms of quantity and quality, and to identify the factors contributing to discrepancies between the planned and actual coal quality following the blending process. To determine the optimal quantity and quality of each coal product in the blending plan, the simplex method was employed with the assistance of POM-QM for Windows version 5 software, alongside the weighting factor method. The final coal blending plan resulted in a total of 55,000 MT with the following quality specifications total moisture of 20.00% (ar), ash content of 6.10% (ad), total sulfur of 1.65% (ad), and a calorific value of 5,350 kcal/kg (ad). The actual blending outcome yielded the same quantity of 55,000 MT, with quality parameters as follows: total moisture of 20.18% (ad), ash content of 5.60% (ad), total sulfur of 1.35% (ad), and a calorific value of 5,340 kcal/kg (ad). The analysis of quality discrepancies revealed several contributing factors the presence of water accumulation in the ROM Stockpile following rainfall, which increased total moisture, the inadvertent inclusion of foreign materials into the feeder, resulting in elevated ash content, the unintentional mixing of coal from different product types, which led to inconsistencies in total moisture, ash content, total sulfur, and calorific value, and the rise in total moisture, which adversely affected the calorific value.

Each workplace has a different potential risk of work accidents depending on the type of industry, technology used, and risk control efforts undertaken by the company. Work accidents are generally caused by two main factors: unsafe acts by humans and unsafe working conditions. In this context, occupational safety and health (K3) is an important aspect that must be implemented in every company to protect workers from hazards that can cause losses, both physical and work productivity. Law No. 13 of 2003 concerning Manpower mandates that every worker has the right to occupational safety protection. This study focuses on UD. Fuad Las Jaya, a company engaged in construction and welding services. This company has a fairly high potential for work accidents considering the type of work performed. Based on employee attendance data in 2025, there is a level of discipline that can be related to working conditions and perceived safety. The severity of accidents is classified into three categories: light, moderate, and severe, which indicates the importance of implementing an effective K3 system. It is hoped that consistent awareness and implementation of K3 will create a safe, healthy, and productive work environment, as well as reduce the number of work accidents in the construction sector.

In the automotive manufacturing industry, efficiency in quality control is a crucial factor to ensure consistent product quality. Conventional Quality Assurance (QA) processes using manual record-keeping often face challenges such as delayed reporting, human errors, and difficulty in tracking historical data. This study aims to design and implement a QA performance dashboard based on digital forms at PT Dharma Polimetal, Tbk, to enhance efficiency in production quality control. The research methodology includes direct field observation, collection of production and QA data, mapping of QA process flows, interactive dashboard interface design, and system trial implementation. The designed dashboard focuses on four main aspects: QA Incoming, QC Line, QC Gate, and Customer Handling, each containing measurable performance indicators and quality parameters. Initial implementation results indicate significant improvements in QA process monitoring, faster reporting of inspection results, and easier real-time data access for both production teams and management. The system enables early detection of potential quality issues, supports rapid decision-making, and facilitates internal and external audits. Moreover, the use of digital forms within the dashboard enhances data accuracy, minimizes human error, and creates structured historical records for long-term analysis. This study provides a tangible contribution to the digitalization of QA systems, strengthening sustainable quality control practices in the automotive industry, thereby ensuring consistent productivity and product quality.

Acid mine drainage (AMD) is one of the major environmental problems arising from coal mining activities. AMD is formed through the oxidation of sulfide minerals, resulting in acidic water with high concentrations of dissolved heavy metals. This condition is characterized by elevated levels of Fe, Mn, and total suspended solids (TSS), which, if left untreated, can pollute nearby water bodies, damage aquatic ecosystems, and pose risks to human health. Therefore, effective, eco-friendly, and low-cost treatment methods are needed to minimize the negative impacts of AMD. This study aims to investigate the effect of activated carbon derived from sugarcane bagasse as an adsorbent for reducing Fe, Mn, and TSS levels in AMD at the sump of PT Alreksa Bara Mitra. The selection of sugarcane bagasse is based on its abundance as an agro-industrial waste and its high lignocellulosic content, making it a potential raw material for activated carbon. The research involved the preparation of activated carbon through carbonization and activation processes, followed by its application to AMD samples with variations in adsorbent dosage and contact time. Laboratory analyses were conducted to measure the concentrations of Fe, Mn, and TSS before and after treatment. The results showed that sugarcane bagasse-based activated carbon significantly reduced Fe, Mn, and TSS concentrations. The highest removal efficiencies were achieved under optimum conditions, reaching 93.14% for Fe, 95.05% for Mn, and 85.04% for TSS. These findings demonstrate that activated carbon from sugarcane bagasse has a strong adsorption capacity for dissolved metals and suspended solids in AMD. In conclusion, sugarcane bagasse-derived activated carbon has potential as an environmentally friendly and cost-effective alternative for AMD treatment, while simultaneously providing added value to agro-industrial waste. This research is expected to serve as a reference for the development of more sustainable mine wastewater treatment methods.

This study aims to analyze the welding results between two commonly used methods, namely Gas Tungsten Arc Welding (GTAW) and Shielded Metal Arc Welding (SMAW), using radiographic testing methods. Welding is an important process in industry that affects the quality and strength of metal joints. In this study, we will examine the quality of welding results from both methods through radiographic testing, which serves to detect defects in welded joints. The GTAW method is known for its cleaner results and minimizes defects, while SMAW is often used because of its convenience and lower cost. The welding process is a crucial factor in ensuring the durability and performance of metal structures, and selecting the right welding method is essential for specific industrial applications. This study will compare the two methods based on the results of radiographic and tensile tests, evaluating factors such as weld strength, defect occurrence, and structural integrity. The analysis will also examine the advantages and disadvantages of each method in terms of weld quality, cost-effectiveness, and practical applications in different industries. It is hoped that the results of this study can provide deeper insights into the selection of the right welding method for industrial applications, as well as contribute to the development of welding technology. Furthermore, the findings will support improvements in quality control and provide a scientific basis for future welding practices in various manufacturing sectors.

In manufacturing industries, machining processes play a critical role in ensuring product quality, precision, and production efficiency. However, in the production of swing arm parts, the machining process has been identified as a bottleneck due to its non-optimal cycle time. One of the main issues contributing to this inefficiency is the disorganized handling of circlip inner parts. These components are often scattered without a designated placement system, which creates significant difficulties for operators when retrieving and installing circlips onto the swing arm. Such abnormalities disrupt workflow continuity, extend production time, and reduce overall productivity. To address this challenge, a circlip feeder machine was designed as a supporting device to assist operators and streamline the machining process. The design emphasizes efficiency, integration, and systematic operation by utilizing readily available workshop materials. The developed feeder machine is equipped with a robust frame construction and has a storage dimension capable of accommodating up to 200 circlips. In addition, mechanical analysis demonstrates that the feeder structure can withstand a maximum applied force of 31,475 N, ensuring durability and reliability during operation. The introduction of this circlip feeder machine directly impacts the production process by reducing operator workload, minimizing delays caused by disorganized parts, and ensuring faster and more accurate installation of circlips. Consequently, the overall machining cycle time is shortened, thereby improving production flow and enhancing the efficiency of swing arm part manufacturing. Beyond immediate time savings, the use of the feeder machine contributes to better resource utilization, reduced ergonomic strain on operators, and improved consistency in product quality. This study highlights the significance of simple yet effective mechanical innovations in overcoming production bottlenecks and optimizing manufacturing processes in automotive component industries.