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The decline in the performance of the die casting machine in 1998 after a long period of producing copper terminals showed dimensional defects and instability in product quality, especially in nozzle clogging, reduced copper flow, crust buildup on the gooseneck, plunger movement obstruction, and hydraulic pressure leaks. The purpose of planning the replacement and repair of die-casting machine components is to obtain replacement and repair costs, replacement and repair schedules for the period 2026, and the ratio of maintenance costs to profits. The replacement and repair planning method includes collecting previous maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component conditions, predicting component service life, predicting labor costs, predicting supporting equipment to be used in maintenance, predicting the time to replace spare parts or reinstall repaired components, estimating replacement and repair costs for the period 2026, and calculating the ratio of replacement and repair costs to profits. The planning results obtained replacement and repair costs for the 2026 period are 75.770.000,- IDR with an estimated die casting machine rental rate of  1,500,000 IDR/hour which has the potential to be rented for 1,200 hours/year, and the ratio of maintenance costs to profits is 10,02 % which implies that the die casting machine with a capacity of 40 units/hour is still suitable for use and has the prospect of generating profits for the next few years.

This study presents a high-accuracy real-time soft failure detection framework for large-scale fiber-to-the-home(FTTH) optical access network using a hybrid ensemble of Isolation Forest and One-Class Support Vector Machine (OCVSM). The proposed model was trainde and validated on a real-word multivariate performance dataset comprising more than 1.8 million samples collected at 5-minute intervals from 50 Optical Line Terminal (OLTs) and over 3,000 Optical Network Terminals (ONTs) across a five-month periode(June-October 2025). Ground-truth validation was performed using 111 confirmed network incidents in October 2025 affecting 12,990 customer. The hybrid ensemble achieved Precision 0.940, Recall 0.982, with an average detection delay of only 7.8 minutes-representing an 87.7% reduction compared to conventional manual response (63.5 minutes). The framework significantly outperforms traditional threesholding and recent ML-based methods while demonstrating practical deployability in live operational enviroments.

A crane is a mechanical device used to move loads from one location to another, with gantry cranes being one of the most commonly used types in the industrial sector, particularly at container terminals. While offering numerous benefits, the use of gantry cranes also presents several risks, such as potential structural failure of the crane, falling loads due to damage to hooks or ropes, and collisions with other objects. Additionally, lifting loads beyond the crane’s capacity can lead to equipment damage and even fatal accidents caused by electric shocks or adverse weather conditions like strong winds and rain. This study aims to identify and minimize workplace accident risks by applying the SWIFT (Structured What-If Technique) method. This method identifies hazards through the "what if" approach and evaluates risks using the Risk Rating Number (RRN), which measures the severity and likelihood of potential hazards. The results of this study show that ARTG and STS gantry cranes have 25% of hazards in the priority one category, while RTG has 20% of hazards in the same priority. From these findings, it can be concluded that risk mitigation should be focused on the ARTG and STS types, which show higher risk proportions. The recommendations from this study are to enhance safety procedures, provide continuous training for operators, and conduct regular crane maintenance to reduce the potential for accidents. By implementing these mitigation measures, it is hoped that workplace safety will be maintained and the risk of workplace accidents at the Semarang Container Terminal can be minimized.

This study aims to analyze the role of the Terminal Inspection Service (TIS) Unit in supervising landside facilities at Minangkabau International Airport. Landside facilities include passenger terminals, drop-off areas, parking lots, and other public spaces that serve as key interaction points between airport services and users. Effective supervision of these areas is essential to ensure safety, comfort, and order within the airport environment. A qualitative descriptive approach was employed in this research, with data collected through field observations, in-depth interviews with TIS personnel and related stakeholders, as well as documentation analysis of existing regulations and supervision procedures.The findings reveal that the TIS Unit plays a strategic role in maintaining service quality and the security of landside facilities. This role is carried out through regular monitoring activities, early detection of potential disruptions, and the handling of various violations in public areas. However, the implementation of TIS duties still faces several challenges. These include limited personnel, which restricts comprehensive supervision of all areas; slow response from relevant units when operational issues are reported; and low discipline and compliance among service users, which further complicates enforcement efforts.To enhance the effectiveness of supervision, this study proposes several recommendations. These include strengthening inter-unit coordination within the airport, providing ongoing training for TIS personnel to improve competency and responsiveness, and implementing an integrated digital reporting system to streamline reporting and follow-up processes. Such measures are expected to support more optimal and sustainable supervision of landside facilities at the airport.

The rapid increase in Ro-Ro (Roll-On/Roll-Off) vessel and vehicle traffic at Tanjung Perak Port, Surabaya, has exposed critical inefficiencies in port operations, particularly at key berths such as Jamrud Utara and Jamrud Selatan. These inefficiencies manifest as prolonged queuing times for Ro-Ro vessels and land-based vehicle congestion, leading to delays in cargo handling and increased operational costs. This study aims to evaluate the operational performance of Ro-Ro terminals based on queue time indicators for both Ro-Ro vessels and vehicles. Employing a quantitative descriptive approach, the research integrates the M/M/c queuing model and Fishbone Diagram analysis to identify systemic causes of operational delays and overcapacity. The study reveals that berth utilization rates exceed 75%, indicating saturation, while limited buffer zones and disorganized traffic flow exacerbate vehicle queues. As a case study, the findings offer data-driven insights and practical recommendations, including schedule optimization, dedicated traffic lanes, and infrastructural upgrades to mitigate congestion. The proposed framework not only enhances service efficiency at the port but also contributes to broader logistics performance in Eastern Indonesia. By combining classical queuing theory with root cause analysis, this research introduces a methodological synergy that can be replicated across other Ro-Ro terminals facing similar challenges. The findings underscore the urgent need for integrated port traffic management and infrastructural adaptability in response to growing maritime logistics demands.

Terminals serve as transportation nodes that play a vital role in supporting community mobility and urban economic activities. As the capital city of Papua Province with a population of 420,577 inhabitants, Jayapura City requires an efficient transportation system to support increasingly dynamic social and economic activities. Entrop Terminal, as a Type A Terminal and the main transportation hub of Jayapura City, serves various transportation modes ranging from inter-city inter-provincial transport, cross-border transport, intra-provincial inter-city transport, urban transport, to rural transport. However, there is a significant problem where users prefer to wait for public transportation outside the terminal due to long queues inside the terminal, creating a shadow terminal phenomenon. This research aims to evaluate the facilities available at Entrop Type A Terminal in relation to the quality of services provided to users. This evaluation is important to identify facility and service deficiencies that cause users to be reluctant to use the terminal optimally. The research results are expected to provide recommendations for facility improvements and service quality enhancement at Entrop Terminal, so that it can function optimally as the main transportation hub and reduce the shadow terminal problems occurring in Jayapura City.

This study aims to examine and describe the extent to which the optimization of public services in the transportation sector is implemented by the Gorontalo Regency Transportation Agency. The approach used is qualitative research with descriptive methods, in order to deeply understand the practices of transportation policies at the regional level. Data collection techniques were carried out through in-depth interviews, participatory observation, and documentation of the activities and policies implemented. The results of the study indicate that the optimization of public services in the transportation sector has been taking place progressively based on three main indicators. First, service effectiveness is reflected in the implementation of regulations in accordance with the law, such as controlling private vehicles parked haphazardly to reduce congestion and routine inspections of public vehicles to ensure safety aspects. Second, efficiency is achieved through technical supervision of vehicles that are not roadworthy, including brake conditions, tire wear, and completeness of route permits, as part of efforts to reduce operational risks and improve service quality. Third, productivity increases through the use of digital technology in socialization activities and the provision of supporting infrastructure such as bus stops, terminals, adequate roads, and traffic signs. These findings indicate that the Gorontalo Regency Transportation Agency has implemented a transportation service optimization strategy that is adaptive and oriented to community needs.