Adi Djoko Guritno

Combining Drum-Buffer-Rope Algorithm and Kansei Engineering to Control Capacity Constrained Worker in a Bioproduction System

Abstract Worker capacity is influenced by various factors of standard time, physical, mood and environment. The Capacity Constrained Worker (CCW) can be described as a worker capacity is close or equal with incoming material so that the fluctuation of incoming material flows possible to shift the CCW into a bottleneck condition of process. Recognizing CCW and bottleneck is essential to maintain the planned product flow in each work station. The objective of the research is to identify and control CCW and bottleneck. The case study of this research is in half-fermented ‘Tempe’ industry. CCW and bottleneck were identified using 4 parameters of standard time, profile of mood status, heart rate and environmental condition. The research results indicated that the CCW was identified on worker of peeling station while bottleneck was identified on the worker of threshing station. The arrival rate of each station inside the Bioproduction system was balanced using the lowest service rate. A buffer time is derived by deviation between service rate of worker in CCW and bottleneck and balanced arrival rate using Drum-Buffer-Rope algorithm. Buffer time was added before threshing and peeling station.

Development of Drum-Buffer-Rope Algorithm to Control Capacity Constrained Machine in a Bioproduction System

Abstract In Indonesia, Bioproduction system has much similarity with the Micro-Small-Medium Agro-industry (MSMA). The some special characteristics of MSMA are the use of conventional semi-manual machine, the importance of skill labor in operations, and less intensive of capital utilization. Recognizing Capacity Constrained Machine (CCM) is essential for balancing the process and material capacity. The CCM can be described as a machine capacity is close or equal with incoming material so that the fluctuation of incoming material flow possible to shift the CCM into a bottleneck condition of process. The objective of this research is to identify CCM and bottleneck in a MSMA process, and developing its control mechanism. The object study of this research is in half-fermented ‘Tempe’ industry. Single queue model with single-server and single queue model with multiple-server were used to identify CCM and bottleneck. The research result shows the workstation of soaking I process could be identified as the CCM and Soaking II could be identified as the bottleneck based on the average waiting time of each station. Drum-buffer-rope algorithm was proposed to control CCM and bottleneck condition. The arrival rate of each station in the bioproduction system was improved in term of balance process using the lowest service rate.

An Application of Data Envelopment Analysis to Determine the Efficiency Level of the Fish Auction Facility in Coastal Area, Java Island

For various reasons, fishermen often sell their catchment sea-fish outside fish auction facility (FAF) which has been provided by the government. This problem is due to the FAF still less well managed, and utilization facilities were inadequate, causing the failure to achieve the predetermined revenue targets of retribution. Thus, it is necessary to investigate the factors within FAF which is less efficient so that it can be improved it can achieve a better performance. This research was conducted using Data Envelopment Analysis (DEA) model with variable return to scale (VRS) oriented, so that it can be used for benchmarking among FAFs in order to know the efficiency level of each FAF. Location of the research conducted in the coastal areas of Java consists of 21 FAF scattered in four provinces (West Java, Central Java, East Java, and Yogyakarta). The result of this research shows amount 12 FAFs are not efficient in the use of FAFs input. The FAFs’ inefficiencies are caused by several parameters, namely, the auction floor area usage factor (91.67%), the number of traders (75%), and the length of the quayside (58.33%). This study recommends to improve the efficiency of the management of FAF through increasing the use of unemployed floor to other fisheries activities, the use of standard weighing facilities, data collection to traders on a monthly regular basis, other uses of the quayside which is not optimal, and standardized use of water and electricity in accordance to the requirements.

Analysis of logistics cost structure of fish cold supply chain in Java Island

Capture fisheries are one of the potential fishery products because the production increase from time to time. This condition causes the fish distribution process become a considerable part because the fish characteristic is perishable if it keep in high temperature. The phenomenon is related to the cold supply chain management. Analysis of the logistic cost structure in the cold supply chain of capture fish is for identifying the proportion of the logistic cost and finding the activities that can be controlled. Strategy in the supply chain is needed to minimize total cost of cold supply chain management. The data collection method used in this research was convenient sampling and snowball sampling by in-depth interview. The research did on May until June 2015 in some fishing port in north and south coast of Java Island. This research shows that cold supply chain consists of four tiers, there are fisherman, collector, trader, and consumer. Cost structure analysis gives dominant cost is in material handlin...

Supply Chain and Logistics Cost Structure Analyses of Spices in Kulon Progo, Yogyakarta, and Magelang, Central Java

Spices have many benefits and occupy an important position in the economy of Indonesia. This study aimed to identify tiers in spices supply chain, to analyze the cost structure of logistic and suggest the right strategy of supply chain management. Spices in this study were limited to ginger and turmeric. Locations in this study were done in Kulon Progo, Yogyakarta, and Magelang, Central Java. This research was conducted by convenience sampling method through an in-depth interview with an interview guide to the respondents throughout the supply chain. The results showed that ginger and turmeric supply chains consist of four tiers; there are farmers, collectors, wholesalers/distributors, and market traders. Both ginger and turmeric, the dominant cost in farmers, wholesalers, and market traders were identified in material handling activity, while the dominant cost in collectors was identified in transportation activity. Strategic recommendations were given for each tier based on the analysis of logistics cost structure that has been done.

Life cycle assessment of fresh fish product in various scale of capture fisheries facilities

There are various models of capture fisheries in Indonesia. One of the distinguishing factors is scale fishing facilities that are used. The differences in scale of these facilities potentially affect the use of inputs and outputs and the resulting environmental impact. In this study, the size of fishing vessels was classified to describe different scale fishing facilities in some areas of the coast of Java. Life Cycle Assessment (LCA) method is used in this study to assess the environmental impacts which are generated during the life cycle of the fish product started from the preparation of fishing operations up to the transportation of fresh fish to the processing unit or local market on some scale fishing facilities. The results showed that the energy and emission generated to transport 1 kg of fresh fish products by smaller scale fishing facilities was higher than the larger one. However, for each trip, the environmental impact caused by that scale was lower than the larger scale fishing facilities. G...

The Material Loss and Failure Process in Sugar Production in Indonesia: A Case

The sugar produced in Indonesia is mainly from sugarcane. In its production, one of the problem is due to losses during the process. As found in this study, a material loss of sugar occured mainly in the milling plant. Based on data taken from a sugar plant in Yogyakarta, Indonesia, on May–June 2012, the left residue (bagasse) was 32 % of total input. The main cause was identified stem from the old machines and facilities that are used to experience a failure, and the lack of concern to the maintenance activity. As a solution, the company addressed a plan for maintenance that was divided into major and minor maintenance. Here, in this study, it propose a measurement on material loss, and see it correlation to the mean time between failure (MTBF) measurement. Since the milling plant is a continuous process, it is necessary to define a utilization capacity. This measure employees the availability schedule of the milling plant for every period (month) reduced by maintenance time that should be done in the middle of the process due to the encountered failure as estimated by MTBF. A correlation test was done to see whether there is a correlation between material loss and a verified utilization time. The result shows that there is a significant correlation, and discuss a need to put such problem in a platform of reliability management.

The Inventory Management of Fresh Vegetables Using Inventory Balance and Across of Its Supply Chain

A wider application of the Integrated Planning Support Framework (IPSF) model can provide more practical basis for benchmarking of real case studies. This study is aimed to determine the opportunity loss and cost of excess inventory of fresh vegetables, the optimal inventory level, and the inventory management based on the types of distribution lead-time. An extensive observation over six-month supply chain tracking from several point of sales of fresh vegetables was conducted to employee the proposed IPSF. The result showed an inefficient supply chain due to an imbalance of customer service and inventory levels. Each tier within the supply chain indicated a dissimilar of inventory size that influenced the inventory decision of each tier. In further, it suggests that the losses of fresh vegetables in term of cost and quality could be reduced by using inventory balance and policies in levelling inventory.

Application of Sampling Plan Methods: Case of Indonesian Sugar Company

A study of sampling plan for controling the quality of bags in a sugar company has been done. The data was taken from 25 random samples for several methods applied including Variable Single Sampling, Quality Index Sampling, and Attribute Proportion Sampling. It was found that the best sampling method is Variable Single Sampling, that gives significant result for all tested parameter and offer an efficient way for the company in doing the inspection and quality control.