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All Journal Industrial and Domestic Waste Management
Defi Irwansyah
Department of Industrial Engineering, Faculty of Engineering, Universitas Malikussaleh, Aceh, Indonesia
Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Engineering Environmental Science

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Situational Awareness as a Human Factor in Near Miss and Crash Incidents Among Student Motorcyclists Diana Khairani Sofyan; Defi Irwansyah; Alfian Mahendra; Anwar
Industrial and Domestic Waste Management Volume 6 - Issue 2 - 2026
Publisher : Tecno Scientifica Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.53623/idwm.v6i2.1311

Abstract

Motorcycle riders are among the most vulnerable road users due to their direct exposure to dynamic traffic environments, while many traffic accidents are preceded by near-miss incidents that provide valuable opportunities for proactive safety evaluation. This study aimed to examine the effect of Situational Awareness (SA) on near-miss and crash incidents among university student motorcycle riders and to evaluate the contribution of the Situation Awareness Rating Technique (SART) dimensions, namely Demand, Supply, and Understanding. A quantitative cross-sectional design was employed involving 96 Universitas Malikussaleh students selected through purposive sampling. Data were collected using a structured questionnaire based on the SART instrument and analyzed using simple and multiple linear regression after confirming the validity and reliability of the instrument and the fulfillment of regression assumptions. The results demonstrated that Situational Awareness had a significant negative effect on both near-miss (β = −0.614, p < 0.001) and crash incidents (β = −0.370, p < 0.001), explaining 48.7% and 42.3% of the variance, respectively. Furthermore, the Understanding dimension consistently showed the strongest influence on both safety outcomes, whereas the Supply dimension was not significantly associated with crash incidents. These findings indicate that improving riders' cognitive ability to recognize, interpret, and anticipate hazardous traffic situations may contribute to reducing near-miss events and crash risks, providing practical implications for motorcycle safety education and hazard perception training among university students.
Applications of Lean Manufacturing to Reduce Waste in the Crumb Rubber Industry Defi Irwansyah; Diana Khairani Sofyan; Muhammad Ashraff
Industrial and Domestic Waste Management Volume 6 - Issue 2 - 2026
Publisher : Tecno Scientifica Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.53623/idwm.v6i2.1333

Abstract

This study focused on reducing waste in rubber powder production using Lean Manufacturing tools and improving process cycle efficiency. A quantitative case study was conducted at PT Perkebunan Nusantara IV Region 1, Gunung Para Plantation, North Sumatra, Indonesia. Waste was identified using the types-of-waste framework and ranked according to its impact on the production process. The selection of appropriate Lean tools was guided by Value Stream Mapping (VSM). The process was analyzed using Current Value Stream Mapping (CVSM), fishbone diagrams, and Future Value Stream Mapping (FVSM). The primary objective was to identify and reduce waste in the crumb rubber production process. The major types of waste identified were waiting time, excess inventory, product defects, and overprocessing. Based on the value stream analysis, several improvement strategies were proposed. The initial process cycle efficiency was 96.26%. After the proposed improvements were applied, particularly those aimed at reducing non-value-added time in the future value stream, process cycle efficiency increased by 1.82 percentage points to 98.08%. In addition, the production lead time decreased from 16,779.32 minutes to 16,467.93 minutes, representing a reduction of 311.39 minutes. The application of Lean Manufacturing and Value Stream Mapping effectively reduced production waste and improved the overall efficiency of the crumb rubber production process.
Co-Authors Alfian Mahendra Anwar Anwar Diana Khairani Sofyan Muhammad Ashraff