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This study aims to analyze production performance and the factors influencing the productivity of mining operations at PT. XYZ during August 2025. The evaluation covers production achievement against the corporate work plan (RKAP) and the owner’s operational plan, equipment availability (Physical Availability), the productivity of loading and hauling units, and various types of loss time that reduce effective working hours. The results indicate that production realization reached only 65% of the RKAP target, while achieving 102% of the owner’s plan for total material. Low equipment availability, high loss time such as no hauler, wait operator, and front preparation, as well as the underperformance of 80-ton and 100-ton units, were identified as the main contributors to production deviation. Additional influencing factors include unit reassignment, suboptimal haul road conditions, and insufficient operational fleet numbers. The study recommends optimizing fleet management, enhancing preventive and predictive maintenance programs, reorganizing hauling workflows, and controlling dominant loss time sources to improve operational efficiency and production target achievement in future periods.

In the modern industrial world, robots like mechanical arms in automotive factories or packaging lines must move quickly and safely. For this, a real-time operating sistem (RTOS) is needed—think of it as a "super-fast brain" that ensures the robot reacts instantly to commands, without delays or errors. This paper analyzes popular RTOS like FreeRTOS and VxWorks for controlling industrial robots, focusing on evaluating performance (speed of operation) and stability (long-term reliability). We conducted tests in a lab using a simple robot that moves its arm to pick up objects. Performance was measured by response time (how quickly the robot stops when encountering an obstacle, ideally under 10 milliseconds) and throughput (how many tasks it can complete per second). Stability was checked through simulations of disruptions, like heavy loads or interfered sensor signals, using metrics such as error rate and time variation (jitter). Results show that FreeRTOS is more efficient for small, affordable robots, with high performance (average response time of 4 ms) but moderate stability (5-10% errors during overload). In contrast, VxWorks excels in stability (errors <2%, stable for up to 95% of tasks on time) for large factory robots, though it requires stronger hardware. Our analysis uses simple models like graphs and repeated tests, without complex formulas, to prove that the right RTOS can boost production efficiency by up to 25% and reduce accident risks.

This study evaluates the retrofit design of the Semat weir on the Kali Gawe in Jepara Regency. The retrofit aims to adjust the weir’s hydraulic capacity to accommodate estimated flood discharges while ensuring the structure’s stability under applied loads. In the agricultural context, adequate water availability for irrigation directly affects crop yields; conversely, the rainy season often increases river flow and flood risk. Irrigation structures such as weirs are therefore required to raise river water levels to divert flow into irrigation channels and to regulate water distribution. Flood discharge estimates were derived from precipitation data and watershed (drainage basin) characteristics. Flood hydrograph planning is a critical design step for the weir. Log-Pearson Type III analysis was used to determine probable precipitation values for several recurrence intervals. Those design precipitation values were then converted into design flood discharges using synthetic unit hydrograph methods, specifically the Snyder, Nakayasu, and Gamma HSS approaches. Employing the Gamma synthetic unit hydrograph for the 50-year return period (Q50) produced a design flood discharge of 2,536.52 m³/s for that recurrence interval. Structural stability analyses of the redesigned weir indicate safety factors well above customary thresholds: overturning resistance factor = 11.6 (required ≥ 1.5), sliding resistance factor = 4.80 (required ≥ 2.0), and piping (internal erosion) factor = infinite (required ≥ 4). All evaluated stability parameters therefore satisfy standard safety criteria.

Regional Disaster Management Agency (RDMA) workers must be on standby and respond for 24 hours, especially if there are emergency. This causes demands on workers and workers become fatigue. The aim of this study is to analyze the factors that influence work fatigue in Tuban Regency’s RDMA workers. This research includes analytical and observational with a cross sectional design. The study was conducted on 56 workers with a simple random sampling system. The dependent variable studied was physical and mental fatigue, while the independent variables consisted of work factors (working hours and workload), emotional demands (responsibility), and organizational demands (work shifts). Data collection was carried out by direct measurement, questionnaires, interviews, documentation and observation then processed with Structural Equation Modeling-Partial Least Square (SEM-PLS). The factors that affect work fatigue are work factors (t statistics = 3.643 and p-values = 0.000) and organizational demands (t statistics = 3.086 and p-values = 0.002), while emotional demands have no effect (t statistics = 0.950 and p-values = 0.342). Loading factors of physical work fatigue (0.917) and mental work fatigue (0.916) are almost the same, so they have the same contribution as a measure of fatigue. Workers who experience work fatigue should conduct regular medical examinations, know the workload limit for one day, organize sufficient work time, regularly rotate work time, stretch in the middle of work activities, prepare work music and videos during breaks.

High-rise buildings such as the World Trade Center Jakarta generally have high inductive electrical loads, so that their reactive power consumption is large and the power factor decreases below the SPLN standard (≤0.85), resulting in increased power losses and operational costs. This study aims to measure the power factor value before and after repairing the detuned reactor and capacitor on the capacitor bank panel, compare the results of field measurements with ETAP simulations, and assess the feasibility of the installed capacitor bank and determine the difference in the results of the ETAP simulation between measurements and load calculations on the World Trade Center building. The methods used include literature review, field observations on the LVMDP panel, MCC and capacitor bank, discussions with supervisors, data collection of current, voltage, kW, kVAR, kVA and cos φ using Lovato DCRG8 and ampere clamp, and load simulation using ETAP software. The results show that the cosφ value increased from 0.70 to 0.95 (an increase of 35.71%), the compensated reactive power reached 204 kVAR (Lovato), 282.6 kVAR (tang ampere), and 415 kVAR (ETAP simulation), with a power factor or cosφ = 0.95. In conclusion, the replacement of detuned reactors and capacitors effectively improves the power factor in the WTC Jakarta Building, reduces reactive loads, and the ETAP simulation results are consistent with field measurements, so that the capacitor bank installed in the WTC building is declared effective in reducing reactive currents, thereby reducing kVAR, kVA loads and improving the efficiency of the electrical system distribution for better energy management

The rapid advancement of science and technology requires universities to provide safe, comfortable, and representative learning facilities. One such initiative is the construction of a five-story lecture building at Dr. Soetomo University, designed with a steel structure as an alternative to reinforced concrete. Steel was chosen due to its high tensile strength, uniform material properties, lighter weight, ease of installation, and strong resistance to earthquake loads. This study aims to design a five-story lecture building with a steel structure that meets the requirements of strength, stability, and safety in accordance with applicable standards. The method applied is structural planning based on SNI 1729:2020, SNI 1727:2020, and SNI 1726:2019 using the Load and Resistance Factor Design (LRFD) approach. Structural analysis was conducted with SAP2000 version 2014 through three-dimensional modeling that considers geometry, material properties, loading, and placement. The results show that the selected steel profiles for beams, columns, and connections are capable of supporting the combination of dead loads, live loads, and seismic loads with safe performance. The maximum stress remains below the allowable limit, and the deflection values do not exceed the permitted deviation. These findings confirm that steel provides efficiency in dimensions and materials while offering practicality and earthquake resistance, and the design produced can serve as a useful reference for future multi-story building projects in earthquake-prone regions.

The availability of electrical energy is one of the important factors during learning activities. However, because the electrical system can be said to be very complicated, starting from the generator center all the way to the consumer, there will most likely be a disruption that causes the flow of power to the consumer to be cut off. One of the factors that affect includes environmental factors, maintenance and other factors, so that the learning process is slightly hampered. The purpose of this research is to maintain electricity supply by automatically switching sources and utilizing renewable energy as a reserve for lighting students' practice rooms. Therefore, a system is needed that automatically regulates the switching of primary sources to backup sources. Automatic Transfer Switch or ATS is a device that automatically switches the main power source from PLN to a backup source such as solar panels by setting the time using Time Delay Relay (TDR). TDR functions to regulate the duration of the power source change operation to meet load needs, especially on small loads such as student practice rooms with a voltage of 220 Volts in one language. The advantage of this system is that it is able to automatically switch electricity supply between PLN and Solar Panels with a controlled time lag. The research method involves the installation of electrical panels and Solar Panels using Solar Charger Controller or SCC, Inverter devices. At the time of the study, the adjustment of the TDR setting to set the time lag on the ATS. SCC settings are carried out to obtain Inputs and Outputs in the optimal battery charging process where the measurement results show that When the load of the incandescent lamp is increased from 50Watt to 300Watt, the current increases from 4.47A to 25.2A, while the voltage decreases from 11.7V to 9.8V. In conclusion, the greater the load, the solar panel voltage decreases and the current increases. The results of the study show that the implementation of the automatic transfer switch system is able to automatically switch the electricity supply between PLN and Solar Panels with a controlled time lag.

This study aimed to examine the relationships among mindset, anxiety, and the achievement of the Assessment of Regional Education Standardization (ASPD) results among ninth-grade students in public junior high schools in Yogyakarta City. Using a quantitative survey approach, the study involved 871 students selected through stratified random sampling based on the TPM stage 1 test scores from schools categorized into high, medium, and low strata for the 2022/2023 academic year. Data were collected using a questionnaire instrument, validated by two expert validators, and construct validity was confirmed through standardized loading factors, showing all items to be valid. Reliability was measured using Cronbach's Alpha, yielding 0.508 for mindset and 0.724 for anxiety. Data analysis employed Structural Equation Modelling (SEM) in R Studio, with model fit assessed through RMSEA, GFI, AGFI, and CFI criteria. Results revealed that the mindset measurement model demonstrated an excellent fit, and the anxiety measurement model also fit the data well after minor modifications. Structural model testing confirmed a good overall fit. Findings indicated that anxiety directly influenced ASPD achievement, with higher anxiety associated with lower results. Mindset did not have a direct effect on ASPD outcomes but negatively influenced anxiety, meaning a stronger growth mindset led to lower anxiety levels. Furthermore, mindset indirectly affected ASPD achievement through its impact on anxiety, demonstrating that fostering a growth mindset can enhance students’ performance by reducing anxiety.

Introduction Shoulder pain is one of the most common complaints of Musculoskeletal Disorders (MSDs) experienced by workers due to non-ergonomic working postures, repetitive movements, and excessive workloads. This condition can reduce productivity and overall quality of life. Objective To increase restaurant workers’ knowledge about shoulder pain prevention through ergonomic education and simple stretching exercises that can be performed independently. Methods A descriptive observational study was conducted involving 20 kitchen workers at Potre Koneng Restaurant. The program consisted of permission procedures, workplace observation, questionnaire distribution, and health education using a leaflet. The educational material included the definition of shoulder pain, signs and symptoms, risk factors, preventive measures, and simple stretching techniques. Results The Form revealed that most workers experienced shoulder pain related to bending postures, lifting loads >5 kg, and limited rest breaks. Following the education session, participants demonstrated improved understanding of proper working posture and the importance of regular stretching, and expressed willingness to practice it during work breaks. Conclusion Ergonomic education and stretching exercises were effective in improving awareness of shoulder pain prevention among informal sector workers. Similar programs are recommended as promotive and preventive measures in high-risk workplaces.

Welding work on ships carries high risks of health disturbances due to exposure to heat, smoke, chemicals, and poor ergonomic work positions. This study aims to identify potential occupational health hazards among welders working on the MV KAREEM ship at PT. Samudra Marine Indonesia in 2025. The study uses a descriptive observational design with total sampling technique, involving 30 welders. Data were collected through direct observation using observation sheets and documentation in accordance with the welding SOP. The results of the study revealed five categories of health hazards. Physical hazards included excessive heat, noise, and poor lighting. Chemical hazards included welding fumes, metal dust, and toxic gases. Biological hazards arose from exposure to microorganisms in the work environment. Ergonomic hazards were related to awkward posture, prolonged static positions, and manual handling loads. Psychosocial hazards included long working hours, high workload, and conflicts among workers. The findings emphasize that welders are prone to health disturbances due to various risk factors. Preventive measures, including improving the work environment, implementing stricter safety standards, and providing occupational health education, are essential to reduce these risks.

Belawan Port is a strategic port in North Sumatra with export-import activities reaching 5,000 tons per year, making it an important terminal in supporting international trade and regional economic growth. This research examines the role of daily work reports in dry bulk cargo unloading operations at PT. Wahana Intradermaga Niaga Belawan as a Stevedoring Company (PBM) responsible for ensuring the smooth process of loading and unloading at the port. The research methodology employs library research approach and direct field observation. The dry bulk cargo unloading process involves the inaportnet system and operates for 24 hours with three work shifts. Activities include four main types of operations: stevedoring (transferring cargo from ship to wharf), cargodoring (transfer from wharf to warehouse), delivery (shipment outside the port), and receiving (acceptance from factory to warehouse). The daily report document is a list of all cargo unloading activities during 24 hours at wharf 112. Daily work reports function as structured documentation of daily activities, conveying work progress updates, supporting performance monitoring, and serving as a reference for operational evaluation. The report's usefulness includes strengthening accountability, reducing misunderstandings, early problem detection, consistency in task implementation, and orderly documentation of unloading activities. Operational preparation involves permit processing according to port regulations, equipment preparation such as hopper, conveyor belt, grab, excavator, wheel loader, and sling ropes. Supporting documents include Bill of Lading, Cargo List, Cargo Manifest, and various operational reports. Obstacles faced include the influence of bad weather, human resource constraints related to workforce professionalism, and land transportation barriers. Related institutions include cargo owners, PBM, shipping agents, port authorities, PT. Pelindo Belawan, and EMKL companies that coordinate to ensure smooth dry bulk cargo unloading operations.

Work fatigue is a significant issue faced by employees in Indonesia, with approximately 65% experiencing symptoms that reduce their concentration and performance. Excessive workload, particularly mental workload, can result in cognitive strain and decreased productivity. This study aims to measure the level of mental workload experienced by quality control employees at PT Delta Dunia Tekstil I using the NASA Task Load Index (NASA-TLX) method. The research also investigates the relationship between employees’ age, length of service, and perceived mental workload through T-tests and F-tests to provide a more comprehensive analysis. Data were collected from 20 quality control employees who are responsible for monitoring textile production under strict standards. Results from NASA-TLX calculations indicate that the average mental workload falls within the high category, with effort and own performance emerging as the dominant dimensions contributing to mental strain. Correlation analysis shows a negative but not statistically significant relationship between age, length of service, and mental workload, suggesting that other factors play a stronger role in shaping employees’ perceptions. The study further highlights fluctuations in employee attendance and quality performance indicators, emphasizing the importance of workload evaluation. To address these issues, recommendations include adding more operators per machine, which is projected to reduce mental workload scores by approximately 33%. Such measures can optimize task distribution, improve efficiency, and promote employee well-being. Overall, the findings suggest that systematic workload assessments using tools such as NASA-TLX are essential for enhancing productivity and supporting sustainable human resource management in the textile industry.

The development of transportation infrastructure in Indonesia continues to be prioritized to enhance regional connectivity, including the maintenance and replacement of bridges that have exceeded their service life. The Semut Bridge in Surabaya, originally a three-span reinforced concrete girder bridge, has experienced structural deterioration due to corrosion and the presence of a central pier obstructing river flow. These conditions have reduced hydraulic capacity, increased sedimentation risk, and heightened the potential for flooding. This study redesigns the Semut Bridge by converting the existing structure into a single-span Howe truss steel bridge. The load analysis refers to SNI 1725 using the Load and Resistance Factor Design (LRFD) method, while structural modeling was carried out both manually and with SAP2000 software. The planning includes the vehicle deck slab, composite girders, main truss members, connections, elastomeric bearings, and abutments. The results show that the bridge deck uses a 20 cm thick reinforced concrete slab with a one-way reinforcement system. Composite girders employ WF profiles, connections use shear connector studs with 25 mm diameter, and the main truss members adopt WF 900×300×16×38 profiles. The total concrete volume required is 282.6 m³, and the estimated steel demand reaches 122,383.79 kg. The single-span design eliminates the central pier, thereby improving river flow capacity while providing a structurally efficient, durable, and easily maintained solution.

This study aims to analyze the effect of transformer oil purification on oil breakdown voltage and evaluate its benefits in maintaining transformer performance and reliability. Oil purification is a crucial preventive maintenance step to preserve insulation quality and prevent operational failures caused by reduced dielectric properties. The study was conducted through several stages, including data collection, oil purification, measurement of breakdown voltage before and after purification, and evaluation of results. Data collection involved measuring the oil’s electrical properties according to SPLN 49-1:1982 and observing results using a Break Down Voltage (BDV) test. Purification of a Trafindo 400 kVA transformer was performed through visual inspection, connecting the inlet and outlet hoses to the purification machine, and circulating the oil until the breakdown voltage met the required standards. Results indicated that the oil breakdown voltage before purification was below standard due to reduced insulation quality caused by water contamination, charcoal particles, thermal degradation, and dissolved gases that weakened dielectric properties. Additional factors such as electrical stress, mechanical stress, and excessive loading also contributed to insulation deterioration. After purification, the oil breakdown voltage increased significantly to meet the standard of >30 kV/2.5 mm, demonstrating that purification effectively restores the oil’s insulating capacity and supports optimal transformer performance. Analysis confirms that the transformer oil remains suitable for use, and routine annual purification is recommended to maintain reliability, efficiency, and operational performance. This study highlights oil purification as an effective preventive measure for transformer stability, extending operational life, and reducing the risk of insulation failure. The findings provide valuable guidance for transformer maintenance in the electricity industry, ensuring safe and optimal long-term operation.

This qualitative research investigates the critical factors inhibiting ship arrival efficiency and their impact on shipping agency performance at PT. Berkah Tata Baruna Banten Branch. Through comprehensive interviews with maritime professionals, port operators, and agency management, the study examines three primary variables: pilot tugboat services, cargo loading-unloading productivity, and document processing efficiency. Utilizing thematic analysis and narrative synthesis, findings reveal significant operational integration challenges that directly affect agency performance metrics. The research demonstrates that synchronized maritime service delivery substantially influences stakeholder satisfaction and business sustainability. Results indicate that technological integration barriers, communication gaps, and human resource development needs constitute primary obstacles to optimal port performance. Beyond identifying constraints, the study highlights how fragmented coordination between service providers creates inefficiencies that extend vessel turnaround times and increase operational costs. Respondents emphasized that transparent communication channels, standardized documentation procedures, and adequate training programs are essential to building resilient port systems. Moreover, the research shows that investment in digital platforms for real-time data sharing could accelerate clearance processes, while workforce development initiatives would ensure higher service reliability. The study contributes theoretically by developing frameworks of integrated maritime service performance and practically by offering policy-oriented recommendations to strengthen agency competitiveness. Overall, the findings provide valuable insights for stakeholders seeking to enhance Indonesia’s maritime logistics capacity, aligning operational improvements with the nation’s broader economic and global shipping ambitions.

. The phenomenon of a potential megathrust earthquake predicted to occur in the coming years has raised widespread concern among the Indonesian public, particularly due to the high vulnerability of existing structures. In response to this issue, this study aims to analyze the structural capacity of buildings in resisting seismic forces and lateral loads, with a specific focus on factory structures. As a civil engineering student specializing in structural engineering, the objective of this research is to examine the behavior, performance, and potential failure patterns of building structures under earthquake loads. The research method employs pushover analysis as a tool for structural assessment, while the evaluation process refers to the guidelines outlined in ATC-40. The analysis results indicate that the factory structure is capable of withstanding a lateral load of 108,587.40 kN, with a controlled roof displacement of 1.5 meters. The structural performance level is categorized under the Damage Control (DO) stage, specifically at performance level SP-2, where the structure remains standing under lateral loads but experiences damage requiring repair before reuse. Furthermore, the failure patterns observed reveal a progressive performance of structural elements, shifting from condition B (Basic), IO (Immediate Occupancy), LS (Life Safety), C (Collapse Prevention), up to E (Extreme Damage). These findings highlight the importance of proper structural design and evaluation in enhancing resilience, ensuring safety, and minimizing potential risks from future megathrust earthquake events.

This study aims to identify, assess, and control risks that arise in container loading and unloading activities at PT Dunia Express Transindo using the Enterprise Risk Management (ERM) approach. Container loading and unloading activities are complex and involve various parties, making them highly susceptible to risks, both from internal and external aspects. Risks that can occur include system disruptions, operational negligence, equipment damage, and environmental factors such as extreme weather that can affect the smoothness of the loading and unloading process. Therefore, the company needs to have a structured, comprehensive, and sustainable risk management system to maintain operational continuity. This research method refers to the COSO framework and the ISO 31000:2018 standard which focuses on the process of risk identification, assessment of likelihood and impact levels, and formulation of appropriate mitigation strategies. Data were obtained through interviews with management, field observations, and analysis of company documents. The results of the study indicate that the implementation of ERM is able to map risks more systematically, making it easier for the company to determine handling priorities. Several risks with a high probability and significant impact received special attention through the implementation of mitigation strategies such as improving information technology systems, routine employee training, and more scheduled equipment maintenance. These findings indicate that ERM implementation not only functions as a risk control tool but also plays a role in increasing operational efficiency, strengthening inter-departmental coordination, and minimizing potential losses that could disrupt company stability. Furthermore, ERM implementation makes a real contribution to increasing the competitiveness of companies in the logistics and stevedoring sector, especially in facing dynamic business challenges and external environmental uncertainty.

The hospital operating room is one of the most crucial facilities in health services, so it requires a stable, reliable, and uninterrupted electricity supply to ensure patient safety and smooth medical procedures. The slightest electrical outage can pose a major risk, given that almost all vital medical equipment in the operating room relies on an electrical power supply. Therefore, the Uninterruptible Power Supply (UPS) system has an important role as a backup solution to ensure the continuity of electrical energy. This study aims to analyze the performance, capacity, and burden of UPS at Siti Fatimah Palembang Hospital using quantitative methods. Data was obtained through direct observation, interviews with technicians, technical documentation, and measurement of current and load power with standard-compliant measuring equipment. The focus of the analysis was directed at the Online Double Conversion type UPS with a capacity of 20 kVA which functions as the main supplier of backup electricity in the three operating rooms. The measurement results show that the total load reaches 8,855.5 VA or equivalent to 44.2% of the total capacity of the UPS. This load comes from 24 units of vital medical equipment, including operating lights, patient monitors, ventilators, anesthesia machines, and electrosurgical devices spread evenly across three operating rooms. With a power factor of 0.92 and a measurement current of 39.8 A, the performance of the UPS is quite efficient and safe to use. This shows that UPS capacity still has spare space to bear additional loads in the event of an increase in the number of medical equipment in the future. The conclusion of this study is that UPS at Siti Fatimah Palembang Hospital is able to work optimally in maintaining the stability of power supply, so that it can ensure the continuity of critical medical services in the operating room.

Vocational High School 2 Purbalingga will continue to face challenges related to teacher performance in 2024. Based on pre-research results and the data obtained, a shortage of teaching staff has been identified, leading to excessive teaching loads and hours, job stress, and dissatisfaction among some teachers with their compensation. This study aims to determine the extent to which job stress, workload, and compensation influence teacher performance at Vocational High School 2 Purbalingga. This study used a quantitative method with a survey approach. The population in this study was all 84 teachers, all of whom were sampled using a saturated sampling technique. Data processing was performed using SPSS version 25. The results showed that job stress had no effect on teacher performance, while workload and compensation had a significant effect. Simultaneously, job stress, workload, and compensation influenced teacher performance. The coefficient of determination value of 0.451 indicates that these three variables influence teacher performance by 45.1%, while the remaining 54.9% is influenced by other factors not examined in this study. Therefore, it is recommended that the school increase the number of teaching staff to reduce excessive teacher workload

STMIK Pesat Nabire is a private university in Papua Tengah that uses a web-based academic information system called eCampuz. User satisfaction evaluation plays a crucial role in improving the quality of academic services at an institution. The purpose of this study is to determine the extent of user satisfaction with eCampuz at STMIK Pesat Nabire, identify the factors influencing such satisfaction, and pinpoint the aspects of eCampuz that need to be improved and developed to enhance user satisfaction. This study employs a mixed-methods approach with an explanatory sequential design. The results indicate that the majority of users are satisfied with five key aspects of eCampuz, 80% for System Quality, 80% for Features and Functions, 87% for Security and Privacy, 80% for Usability, and 80% for User Satisfaction. Several shortcomings and challenges were also identified, such as the absence of automatic notifications when instructors post materials, assignments, and attendance records, the lack of date markers on materials posted by instructors, making it difficult for students to distinguish between new and old materials, errors and slow loading times in attendance records, limited file upload capacity, and the inability to accept certain file formats. Regular evaluations of user satisfaction are needed to further improve the system and ensure that user satisfaction is met.