Mixed-load machine utilization improvement and transfer batch size optimization using hybrid simulation approach

Current technological development has increased the competitiveness in the manufacturing system, especially for the electronic industry. This research is based on case company in the automatic testing and label printing processes of a multinational hard disk drive (HDD) manufacturing system with the objective of improving the tester utilization while achieving the production target. The problem is complex as the testers are employed to simultaneously load multiple product families. Each product family has several models with different testing durations. In addition, apart from the high product mixes for each product family undergoes different process flow making the problem more complicated. The company has difficulty to achieve the targeted tester utilization of 96%, as the current utilization is 71.14%. As the problem is too complicated to be solved by an analytical method, a hybrid simulation approach was employed to solve the operation machine allocation and the transfer batch size problem. Firstly, the problem of mixed-load tester was formulated through a mathematical model. Then, a simulation model was designed and developed to evaluate the scenarios of the mixed-load tester configurations. After that, the multi criteria decision making techniques were employed to determine the best scenario. Finally, the transfer batch size was optimized to improve system WIP. The final proposed configuration successfully increased the tester utilization by 24.89% and reduced the number of testers by 37.77% for Tester A and by 27.27% for Tester B while improving the throughput by 6.88% compared to the current system. In addition, the transfer batch size was reduced from 120 units to 86 units and system WIP was successfully reduced by 6.43%

Developing Hybrid Simulation Model to Improve Road Traffic Management

Yogyakarta has increasing trends in the number of vehicles and consequently intensifying the traffic volume and will effect to higher emission and air pollution. Traffic lights duration plays a vital role in congestion mitigation in the critical intersections of urban areas. This study has objective to minimize the number of vehicles waiting in line by developing the hybrid simulation method. First of all, the MKJI and Webster method were calculated to determine the green traffic light. Then, the simulation model was developed to evaluate the number of vehicles waiting in line according to different duration of green traffic lights from MKJI and Webster method. A case study will then be provided in Pelemgurih intersection located in Yogyakarta, Indonesia for demonstrating the applicability of the developed method. The result shows that the duration of green traffic lights calculated by Webster method provides lower number of vehicles waiting in line. It is due to the short duration of green traffic light resulted by Webster method so that the traffic light cycle becomes shorter and it effects the number of vehicles waiting in line which is lower than MKJI method. The results obtained can help the generating desired decision alternatives that will important for Department of Transportation, Indonesia to enhance the road traffic management with low number of vehicles waiting in line

Capacity Planning For Mixed-Load Tester Under Demand And Testing Time Uncertainty

Capacity planning is an important decision in production planning as it determines the capacity to install in order to satisfy customer demands and also to allocate products to those capacities.This research is based on mixed-load machine problem which is categorized by multiple products that can be processed simultaneously with different processing time.The problem is further complicated with high product varieties and high demand variabilities.This research was conducted based on a case company from a multinational manufacturing company in Malaysia that produces hard disk drives.The study focused on the automated testing process characterized by long lead time and high product variability.Each testing machine with 2880 slots is a mixed load tester with the ability to load and test multiple product families simultaneously.In addition,the uncertain demand and testing time makes the problem more challenging. Currently,the company’s issue is low tester utilization of about 71%,well below the target of 96%.The objective of this research is to improve tester utilization while achieving the production target under uncertain demand and testing time and also to determine the break-even point on the testers required.A novel approach of integrating a mathematical model,robust optimization model,genetic algorithm,simulation model and cost–volume –profit analysis was developed.Firstly,a mathematical model of mixed-load tester was formulated.Next,a set of discrete scenarios was proposed to address uncertain demand and testing time.A robust optimization and genetic algorithm model was developed to optimize the number of testers under the described uncertainties.Next,these scenarios were simulated using the Pro Model simulation software to validate the proposed models and to evaluate throughput and tester utilization.Finally,the cost–volume–profit analysis was performed for scenarios that require additional testers at various levels of uncertainties.The results showed that the proposed solution improved tester utilization by 25% compared to the current system.This research has contribution by developing novel hybrid methodology and able to provide useful insights to assist company’s managers to plan and allocate resources according to variations in customers’ demands and testing time

Optimizing shipping routes to minimize cost using particle swarm optimization

Product shipping is important in the economic process in the company. Efficient product shipping routes should provide low transportation costs. This study based on a case company of CV. Kayana, a distributor of “Sari Rotiâ€, has 4 motorbikes and 2 cars. Each vehicle has their own shipping routes. Nowadays, high distance for each route results on high transportation cost. Therefore, the objective of this study to minimize the distance and cost of product shipping by developing shipping algorithm using Particle Swarm Optimization (PSO) for Traveling Salesman Problem (TSP). The MATLAB software was employed to solve this problem. The solution is obtained by varying the amount of particles and number of iterations. Experimental results proved that the developed PSO is enough effective and efficient to solve shipping routes problem. The results show the proposed model have lower distance and transportation cost. It helps the company in determining the routes for product shipping with minimum transportation cost

Designing of Work Facility for Ecobrick Material Using Ergonomic Intervention to Reduce Muscoloskeletal Disorder

Kamulyan waste bank is a place to collect the waste from the household around Lowanu Village, Brontokusuman, Mergangsan, Yogyakarta. This waste is distributed to garbage collectors and sorted. Plastic waste that cannot be recycled is used as material for making ecobricks. Ecobricks are materials made from used plastic bottles filled with plastic sachets, plastic bags, and similar materials that are compressed. In making ecobricks, workers perform activities in a sitting position on the floor with both legs folded in and a slightly bent posture. This work attitude causes muscle complaints in the upper and lower neck, upper arm, right elbow, left wrist, and left hand. The purpose of the study was to improve work attitudes to reduce muscle complaints in body parts by designing ergonomic work facilities. This research was conducted with ergonomics intervention on the design of ecobrick plastic compaction work facilities with the Nordic Body Map-VAS Modified Questionnaire. The muscle complaints of the workers' body parts were determined using the Nordic Body Map questionnaire. The results of the study provide a design for compaction of ecobrick plastic materials with dimensions of table length 134.44 cm, table width 66.39 cm, table height 71.63 cm, length of seat mat 41.41 cm, width of seat mat 43.49 cm, height seat 44.51 cm, backrest height 55.5 cm, and backrest width 45.88 cm. Based on the NBM-VAS questionnaire, it shows that the initial condition of pain or pain in the upper neck and lower neck with a moderate pain value is aimed at a scale of 6.5 cm and 7.3 cm to mild pain with a scale of 4.2 cm and 4.3 cm. . Moderate pain in the left wrist and left hand with a scale of 6.1 cm, respectively, to no pain on a scale of 3.1 cm and 3 cm

Turnitin-IJIES 2020_ Developing Hybrid Simulation Model to Improve Road Traffic Management

Yogyakarta has increasing trends in the number of vehicles and consequently intensifying the traffic volume and will effect to higher emission and air pollution. Traffic lights duration plays a vital role in congestion mitigation in the critical intersections of urban areas. This study has objective to minimize the number of vehicles waiting in line by developing the hybrid simulation method. First of all, the MKJI(Manual Kapasitas Jalan Indonesia)and Webster method were calculated to determine the green traffic light. Then, the simulation model was developed to evaluate the number of vehicles waiting in line according todifferent duration of green traffic lights from MKJI and Webster method.A case study will then be provided in Pelemgurih intersection located in Yogyakarta, Indonesia for demonstrating the applicability of the developed method. The result shows that the duration of green traffic lights calculated by Webster method provides lower number of vehicles waiting in line. It is due to the short duration of green traffic light resulted by Webster method so that the traffic light cycle becomes shorter and it effects the number of vehicles waiting in line which is lower than MKJI method. The results obtained can help the generating desired decision alternatives that will important for Department of Transportation, Indonesia to enhance the road traffic management withlow number of vehicles waiting in line

Turnitin JITI 2020_Reducing Environmental Impact on SME Metals Production Process Using Life Cycle Assessment and Analytical Hierarchy Process Method

The ABC metal SME produces some wastes, such as liquid waste, solid waste, and smoke. The problem is hazardous waste dumped directly into the environment without any waste treatments which had bad impact on the environment around its SME. Therefore, this research is proposed to improve the production process of metal that can reduce the environmental impacts. The Life Cycle Assessment (LCA) method is developed to identify all the processes that have an impact on the environment and also to calculate the energy used. The values of environmental impact are calculated using Simapro 9.0 Software. In addition, Analytical Hierarchy Process (AHP) method is employed to determine the best alternative fuel according to four criteria, such as temperature, price, emission, and fuel consumption. The results show the process that has the greatest environmental impact is the metal smelting process. It is caused by the source fuel in this process was used oil. The usage of used oil can be the sources of air pollution that causing health problems in the respiratory tract such as bronchitis and asthma. Some alternative fuel was proposed, however, fuel gas is the best alternative among others according to the expert opinions. For the managerial insight, this research can be suggestion for SME to choose the best fuel in the production process that considering economic and environmental aspects

Designing Standard Operation Procedure to Produce Environmentally Friendly Liquid Detergent

Washing clothes is an activity that is often done by people in the world. However, detergents sold in the market are harmful to human skin and aquatic ecosystems in rivers. Therefore, this research focuses on environmentally friendly detergents that can minimize the impact on the environment and humans. This study aims to develop standard operating procedures (SOP) in the production of environmentally friendly detergents. This was conducted by developing the initial SOP design, simulating the initial SOP, and identifying problems. Then, followed by improving, designing, and simulating the final SOP. The results of this study acquire SOP that generates products with better consistency and quality