Spare Parts Supplier Selection Design: A Case Study of A Railway Company

Spare parts support is essential for rolling stock maintenance management. The current supplier selection model determines the selected supplier based on evaluating one aspect of the criteria (product aspect). The selection of suppliers with poor performance occurred between 2018-2020 related to the delivery of goods that exceeded the deadline and goods that did not meet specifications. The first objective of this research is to analyze and determine the relevant priority criteria for selecting suppliers of rolling stock spare parts for railway companies. The second objective is to determine the rolling stock spare parts supplier by using the evaluation criteria determined in the previous process. The method used in this research is the integration of the Fuzzy Delphi Method (FDM), Analytical Hierarchy Process (AHP), and Technique for Others Preference by Similarity to Ideal Solutions (TOPSIS). FDM is used to select important criteria for the selection of suppliers of rolling stock parts. AHP is used to assist in choosing various criteria through evaluation in determining the criteria's weight. TOPSIS is used to assess supplier ratings. A total of 13 criteria from 19 alternative criteria have been selected for railway companies, especially in selecting rolling stock spare parts suppliers. Furthermore, the selection becomes the basis for bidding. Finally, Supplier A is the supplier with the highest relative closeness value (0.591), followed by Supplier B (0.545), and the lowest is Supplier C (0.282).

Grey-based Taguchi Method to Optimize the Multi-response Design of Product Form Design

This paper presents a multi-response optimization method that uses the grey-based Taguchi method as the integrative product form design optimization method, and it serves as a tool for product form design to determine the optimal combination of design parameters in Kansei engineering (KE). This method is unique in that it combines the Taguchi method (TM) and grey relational analysis (GRA), allowing it to take advantage of the benefits of both methods. The TM is used to design experiments and generate combinative product form design samples which can be used to improve product quality. The GRA is applied to multi-response optimization problems. Factor effect analysis and analysis of variance (ANOVA) are used to determine which combinations of design parameters will result in the optimal product design. To demonstrate the applicability of the grey-based TM, a case study of a car form design is presented, and a confirmation test is performed to verify the performance of the optimal product design. The results show that the grey-based TM can deal with optimization problems with multiple Kansei responses and determine an optimal car form design that is representative of the consumers' perception in a systematic manner. The confirmation test results also show that the optimal product design generated by the grey-based TM can be used to improve the overall quality of a product form.

Proposing Electric Motorcycle Adoption-Diffusion Model in Indonesia: A System Dynamics Approach

In 2019, the number of conventional vehicles in Indonesia reached 133,617,012 units, dominated by motorcycles of 112,771,136 units and passenger cars of 15,592,419 units. The high number of conventional motorcycle users can increase the number of pollutants and combustion emissions in the environment. This condition has encouraged the transition to a sustainable transport system that will be needed for decades to come, especially for the electric motorcycle to resolve the issue. This research aims to predict and estimate the market share of electric motorcycles by considering life cycle cost per kilometer. System dynamics simulations are developed to model the adoption-diffusion of electric motorcycles in Indonesia. This model has four main modules: an electric motorcycle module, a conventional motorcycle module, an economy module, and a consumer market module. This model shows a positive trend of EM market share from 2021-2030, with the market share value of EM is 0,411 in 2030. The development of retail price subsidy and electricity price scenarios is also carried out to determine the right policies to accelerate the adoption-diffusion process. Based on the scenario, the provision of retail price subsidy and a decrease in electricity price can increase the value of the EM Market Share.

How Organizational Culture Moderate the Effect of Total Productive Maintenance Practice on Organization’s Operational Performance? Evidences from Indonesian Mining Industry

The industry needed a system to support its operation when most of the processes were done by equipment or machines. Total Productive Maintenance (TPM) was a system to ensure all equipment or machines run in optimal performance for long period by fully supported by top management until the bottom level. Implementation of this system in the mining industry was still seldom due to some factors and organizational culture was one of the reasons. The purpose of this research was to analyze the influence of TPM implementation on operational performance by moderating the effect of organizational culture in the mining industry by using a two-step approach of structural equation model (SEM). The research type was under explanative research with hypothesis testing from primary data that was obtained from distributing questionnaires and direct interviews in the field which was analyzed by using Lisrel 8.7. This research showed that the construct of TPM has a significant impact to influence operation performance directly in the mining industry with a t-value of 3.54 and organization culture also increases the significance by moderating effect with t-value of interaction 5.28 was higher than 1.96 while organizational culture was not significant to influence operational performance directly that was showed by t-value 1.22. This research had a novelty for studying TPM practice in Indonesian mining by using SEM to analyze the moderating effect of organizational culture. The managerial implication of this research was a guideline for decision-makers to implement TPM by considering developing, group, hierarchical, and rationale culture to improve operational performance in the Indonesian mining industry.

A Hybrid Model for Green Supplier Selection and Order Allocation: DEMATEL, ANP, and Multi-criteria Goal Programming Approach

Increased competition in the industrial world forces companies to increase their competitiveness through Green Supply Chain Management (GSCM). The key to the success of GSCM is the selection of suppliers and the allocation of the proper order by taking into account environmental aspects. This decision involves several criteria and must also pay attention to the relationship between criteria. This study proposes a hybrid procedure to solve Green Supplier Selection and Order Allocation (GSSOA). The integration of Decision Making Trial and Evaluation Laboratory (DEMATEL), Analytic Network Process (ANP), and Multi-Criteria Goal Programming (MCGP) are proposed to solve this problem. The DEMATEL is used to calculate the relationship between criteria. Furthermore, the ANP is proposed to determine the weight of the criteria and supplier ranking. Finally, the MCGP method is offered for allocating orders based on priority suppliers. A case study on the food industry in Malang, Indonesia, was conducted to apply this procedure. The results showed that the low defects rate criterion is the most important compared to other criteria. The best supplier was successfully selected, and the order allocation was completed. Order allocation priority is to suppliers D, C, A, and B. This study also presents a sensitivity analysis for order allocation.

Identification of Internal Academic Factors Affecting Academic Entrepreneurship: A Case Study

Academic Entrepreneurship is an entrepreneurial activity conducted by scientists/academics who market their research results commercially to achieve specific economic benefits or rewards. This research focuses on academic entrepreneurship that occurs at Andalas University. There is still a lack of academics whose research products for commercialization are about 22.73%. It is because there are factors that influence academic entrepreneurship activities at Andalas University. One of them is the internal academic factor. The internal factors are Control System, Organizational Culture, Human Resource Management System, Organizational Structure, and Academic Leadership Behavior. The purpose of this study is to analyze the university's internal factors on academic entrepreneurship. This research uses a quantitative approach derived from 106 Andalas University academics with Structural Equation Modelling (SEM) methods with SmartPLS Software. The result obtained in this study is that the control system exerts a positive and negative influence on academic entrepreneurship. In contrast, other factors have a significant positive influence on academic entrepreneurship. The research results show that the university's control system, organizational structure, and human resources had no significant positive effect on academics at Andalas University. Meanwhile, entrepreneurial behavior and organizational culture have a significant positive effect on academic entrepreneurship at Andalas University. Further research should be analyzed for all universities with innovative products and are ready for commercialization throughout Indonesia. This research is still a case study and needs to be developed.

Analyzing the Vibration Exposure to the Safety and Health at Workplace: A Case in the Urea Granulation Unit of the Fertilizer Factory

This study aims to evaluate the vibration exposure experienced by workers in the Urea Granulation Screen Unit (UGSU) at the fertilizer factory in Aceh, Indonesia. This study involved 30 labors in charge as operators, mechanical maintenance officers, electrical maintenance officers, instrument maintenance officers, and inspectors. The measurement of vibration was carried out using a Triaxial Accelerometer with Integral Magnet and shows that the vibration exposure on the factory floor of the urea granulation screen unit occurs vertically with a minimum value of 0.298 m/s2 and a maximum of 1.630 m/s2. According to ISO 2631-1:1997, the maximum vibration values that occur are categorized as a likely health risk zone and result in uncomfortable reactions to the workers. Furthermore, this study analyzes the effect of vibrations on musculoskeletal problems using a Nordic Body Map (NBM) questionnaire. It reveals that the average score of musculoskeletal complaints is 71.6, which defines a high degree of pain. The results of the NBM questionnaire also showed that the vulnerable part of the body which experienced musculoskeletal complaints is the knee. The result of vibration exposure on this body part shows the highest value of 3.437 m/s2. To minimize occupational diseases and accidents, it is necessary to manage a working system that takes into account legal standards, ideal working time, and working shifts in the work area.

Analysis of Environmental Impact and Municipal Waste Management Strategy: A Case of the Piyungan Landfill, Yogyakarta, Indonesia

The ever-increasing volume of municipal waste in Yogyakarta brings overload capacity problems to the Piyungan Landfill. This circumstance results in environmental pollution which harms the local residents. Therefore, this study was conducted to determine the impact of pollution in the Piyungan Landfill from an economic, environmental, and social perspective. Furthermore, this study aims to formulate a waste management strategy in the landfill using the fishbone analysis to find out the root causes of existing problems, the stakeholder analysis method to determine the role of each stakeholder involved, and the SWOT analysis method to determine potential strategies for waste management. From those analysis methods, it is concluded that there are six root causes in the landfill, namely the waste management process, the amount of waste, landfill facilities, the technology used, the implementation process, and government policies. This study recommends several waste management improvements from the combination of strengths and opportunities factors (SO Strategy). The combination of these strategies includes: (1) establishing cooperation policies with foreign parties. (S1, O1); (2) optimizing budget and waste management technology. (S2, O2); (3) providing transportation facilities and technology to optimize the recycled waste business. (S3, O2, O3); and (4) maximizing resources to optimize the recycled waste business. (S4, O3). These strategies are expected to be able to increase the capacity and capability of the Piyungan Landfill in managing waste and overcoming environmental pollution.