Journal La Multiapp

Traffic Impact Analysis of an Underpass on the Performance of Nearby Signalized Intersections Using VISSIM

Yosua Purba — 2026-01-11

Medan City is one of the metropolitan cities with a high level of congestion and population density, resulting in traffic jams, delays, as well as air and noise pollution. This study aims to analyze the performance of intersections on S.M Raja – Halat road, Brigjend Katamso – Mesjid Raya road, and Brigjend Katamso - Pelangi road before and after the operation of the underpass at the Ir.H.Juanda – Brigjend Katamso road intersection using vissim software. Data were obtained from traffic surveys such as vehicle volume surveys, road geometry, traffic signal cycle times, and vehicle speeds. The data obtained from the vissim software simulation results include queue lengths, delays, and level of service at the intersection. For the simulation results at the Ir.H.Juanda – Brigjend Katamso road intersection before the operation of the underpass, the average queue length was 274.3 m and the average delay was 307.38 sec/vehicle, with an average level of service of F (very poor). After the operation of the underpass, the average queue length was 8.38 m and the average delay was 0.96 sec/vehicle, with an average level of service of A (excellent). With a 5-year scenario, the average queue length was 38.53 m and the average delay was 12.34 sec/vehicle, with an average level of service of B (good). Thus, a significant difference is clearly visible between before and after the operation of the underpass, such as the results of queue lengths, delays, and service levels, which have caused new conflicts at the intersections closest to the underpass.

Waste Analysis in Connection Clamp Production Process with Lean Manufacturing and Failure Mode Effect Analysis

Faishal Hidayatulloh — 2026-01-19

UD H and M Electric is a manufacturing company engaged in the production of medium voltage overhead line (SUTM) components, one of its products is the Connection Clamp. The purpose of this study is to determine the level of waste that occurs and provide suggestions for improvements to reduce waste. The research data used is questionnaire data with respondents who meet the qualifications and know the entire flow of the Connection Clamp production process, as well as waste data that occurs during the production process. To determine the level of waste that occurs and provide suggestions for improvements, the Waste Assessment Model, Process Activity Mapping, Fishone Diagram, and Failure Mode and Effect Analysis methods are used. In the Waste Assessment Model method, the top three critical levels of waste were obtained, namely waste defect of 19.55%, waste motion of 16.88%, waste transportation of 16.10%. In the Failure Mode and Effect Analysis, the Risk Priority Number (RPN) value was obtained from the top three wastes with each sub-waste, namely waste motion sub-waste lifting products manually with a score of 280, waste motion sub-waste rearranging before the process with a score of 240, waste transport, namely the distance of the work station is less than optimal with a score of 200, waste reject sub-waste cracked plates with a score of 168, waste Defect, namely imperfect layers with a score of 168.

Usability Evaluation of a Virtual Reality Simulation System for Earthquake Preparedness Using the System Usability Scale (SUS) Method

Romeo Putra Dirama — 2026-01-28

This study aims to evaluate the usability level of the Virtual Reality (VR) simulation system for earthquake preparedness training at the Environmental Agency of East Java Province using the System Usability Scale (SUS) method. The testing was conducted with nine respondents who performed two task scenarios in the simulation and subsequently completed the SUS questionnaire. The analysis covered three main aspects of usability: effectiveness, efficiency, and user satisfaction. The results showed an effectiveness level of 100% (“Highly Effective” category), an average efficiency of 0.01758 goals/second (“Very Fast” category), and an average SUS score of 73.88, which falls into the “Acceptable” category with an adjective rating of “Good.” These findings demonstrate that the VR simulation has strategic potential as an effective and efficient interactive training medium for improving the understanding of earthquake evacuation procedures. Nevertheless, improvements are needed in interface consistency and in reducing the initial learning curve to optimize the user experience.

Design of Mine Distribution System at Nickel Mining Front of Pt. Cipta Djaya Surya

Mulyadi Mulyadi — 2026-01-28

Nickel mining activities at PT. Cipta Djaya Surya in Molore Village, North Konawe Regency, face a serious problem in the form of stagnant runoff in the mine front area due to the lack of an adequate drainage system and sedimentation pond. This condition not only disrupts smooth mining operations but also has environmental impacts, such as reddish discoloration of coastal waters and potential siltation. This study aims to analyze surface runoff discharge, design open channel dimensions, and design settling ponds appropriate to the hydrological and topographical conditions of the study site. The methods used include collecting rainfall data for the past 10 years from the Meteorology, Climatology, and Geophysics Agency (BMKG), hydrological analysis using the rational method, hydraulic calculations using the Manning equation, and planning channel and settling pond dimensions based on runoff discharge. The results indicate that the maximum runoff discharge in the study area can be managed by designing a trapezoidal open channel with dimensions appropriate to the flow capacity, while the designed settling pond can accommodate the runoff volume without overflowing. The implementation of a planned drainage system is expected to maintain smooth mining operations, minimize the risk of landslides, and mitigate the impact of coastal environmental pollution. Therefore, this research supports the implementation of Good Mining Practice (GMP) principles and can be used as a reference in sustainable mine drainage planning.