Publication Search

This study aims to determine and analyze service waiting times, identify the root causes of long queues, and develop a strategy to improve service performance at the 5361137-gas station (SPBU) at the Surabaya-Gresik Toll Rest Area. The research method used is a mixed-methods approach with an exploratory sequential design. This study combines quantitative analysis using Queuing Theory to measure system performance (arrival rates and service times) and descriptive qualitative analysis using a Fishbone Diagram. Data were collected through direct observation, interviews, and g-form techniques. The results indicate that the current queuing system performance is in a critical or severe condition, indicated by a server utilization rate of 0.94 to 1.02 during peak hours. The average time spent by vehicles in the system is 14.3 minutes, of which 9.6 minutes (67%) is spent waiting in the queue. Fishbone diagram analysis revealed that the root cause of the main problem lies in the complex interaction of factors: Machine factors (EDC signal failure and pump repair downtime), Human and Method factors (implementation of static shifts and reactive maintenance), and Environmental factors (narrow layouts that hinder large vehicle maneuvers). As a solution, this study formulated a hybrid improvement strategy that includes short-term business process engineering (the use of Floating Staff and lane segregation) and long-term investment in additional pumps to change the queuing model from Single Channel to Dual Channel. This strategy is expected to reduce the utility level to a safe zone below 0.80 with a target waiting time of 3–5 minutes.

This study aims to analyze the quality control of white crystal sugar production at ABC Sugar Factory using the Statistical Quality Control (SQC) method. The research employed a descriptive quantitative approach with a case study design. The primary data consisted of production volume and defective product data during the 2024 production period, while supporting data were obtained through observation and interviews with the Quality Control department. The analytical tools applied included check sheets, histograms, Pareto diagrams, p control charts, and fishbone diagrams. The results show that from a total production of 190,745.89 tons, defective products amounted to 66.70 tons, representing 0.33 percent of total output. The identified defects consisted of wet sugar at 45 percent, brownish sugar color at 30 percent, and oversized sugar crystals at 25 percent. Defective products occurred only during the first to third production periods, while no defects were observed from the fourth to seventh periods. The p chart analysis indicates that the production process was statistically out of control in the early periods but became stable and controlled in the subsequent periods. From a managerial perspective, these findings provide practical guidance for improving manufacturing quality through enhanced process control, equipment maintenance, and workforce capability development.

This study aims to analyze the bread production system of UMKM Roti D’One using the Input–Process–Output (IPO) approach and to identify product defects through the application of the Seven Tools of quality control. Data were obtained through interviews, field observations, and production recording. The IPO analysis shows that the production process is carried out manually and relies heavily on worker skills and household-scale equipment. Based on the checksheet, two dominant types of defects were identified—non-soft texture and uneven color—resulting in 30 defective products out of 1,400 breads produced in one week. The Pareto analysis indicates that texture defects contribute the largest portion (56.7%) of total defects. Meanwhile, the fishbone diagram reveals that the main causes originate from raw material inconsistency, equipment limitations, variations in worker skills, and manual production methods. This study suggests improvements related to raw material standards, production consistency, and worker training to reduce defects and enhance the overall quality of Roti D’One products.

This study analyzes the quality control of lamb rendang products at CV. Mitra Tani Farm using three Statistical Quality Control (SQC) tools: the checksheet, Pareto diagram, and Fishbone diagram. The research was conducted to identify major product defects and their root causes in the canned lamb rendang production process. A descriptive quantitative method was applied through direct observation, interviews, and documentation. Data were collected using a checksheet to record defect types and frequencies, then analyzed with Pareto and Fishbone diagrams to determine dominant issues and underlying factors. The results showed that labeling errors were the most frequent defect, followed by inaccurate sterilization and machine overload. These problems were mainly caused by limited operator skills, non-standardized procedures, and inadequate machine performance. The findings indicate that improving operator training, refining standard procedures, and maintaining equipment are essential to enhance product quality and consistency.  

This study aims to analyze quality control at the Lekkerz Enakk business in Bogor branch using three statistical tools, namely Checksheet, Pareto Diagram, and Fishbone. Data collection was conducted through interviews with the owner, admin, and employees, as well as direct observation at the nearest branch location regarding the production process. Based on the results of the observation, three defects were found that frequently occurred during the production process within a period of seven days with the most dominant lekker product damage being a non-crispy texture (42%), and non-uniform color (27%). Based on the fishbone analysis, these defects were caused by Man (human), Machine (machine) factors. The implications of this study indicate that it is necessary to improve operational standards, workforce training, and supervision of raw materials and production equipment to maintain the quality and efficiency of the lekker production process at the Lekkerz Enakk business in Bogor.

Drug stock-outs are an indicator of pharmaceutical management failure that directly affects patient safety and the quality of hospital services. Gatoel Hospital Mojokerto experienced an increase in the percentage of drug debt from 3.14% in January to 6.20% in July 2025, with 1,607 patients affected. This study aims to identify the factors causing drug stock-outs and formulate preventive strategies through the optimization of the Minimum-Maximum Stock Level (MMSL) system based on the Hospital Information System. A mixed-method approach was used, combining secondary data analysis (January–July 2025) and in-depth interviews. Fishbone analysis was applied to identify root causes, USG analysis to determine priorities, and SWOT analysis to formulate intervention strategies. Priority drug classification was carried out using the ABC-VEN method. The intervention involved implementing an MMSL pilot project for 150 drug items under Pareto category A. The analysis identified six dimensions of stock-out causes: man, materials, methods, machines, measurement, and environment. The highest priority issue was drug demand forecasting based on historical data (USG score: 125). SWOT analysis placed the organization in quadrant II, recommending a Weakness-Opportunities (WO) strategy. MMSL implementation was initiated through the development of SOPs and the entry of 150 priority drug items into the system. Drug stock-outs are caused by multifactorial issues that require systemic intervention. MMSL optimization has the potential to serve as a long-term solution, provided there is expanded coverage, strengthened human resource capacity, and comprehensive system integration.

Amphibian Cessna 172 SP is an aircraft designed to operate in aquatic environments and is frequently exposed to seawater, which is highly corrosive. Such exposure poses a serious issue of corrosion affecting both the structure and components of the aircraft, particularly the floats, lower fuselage, and propeller. Corrosion not only reduces the quality and integrity of the material but also potentially compromises flight safety and increases maintenance costs. This study aims to analyze the causes of corrosion on the Seaplane Amphibian Cessna 172 SP using the fishbone diagram to identify the main contributing factors, including material, method, environment, manpower, and machine. In addition, the 5W+1H approach is employed to examine the problem in greater detail and develop preventive strategies. The results of the analysis indicate that the dominant factors causing corrosion are the high intensity of direct contact with seawater, suboptimal cleaning processes due to limited manpower, and the use of cleaning agents not fully compatible with aircraft materials. Mitigation efforts include implementing more effective cleaning procedures, applying anti-corrosion chemicals such as AeroShell Fluid 41, Bonderite Turco S.S.2, Ardrox AV-15, CorrosionX, Toolmates Dry Film Lubricant 6075, and Ultra Tef-Gel, as well as conducting scheduled inspections at specific intervals. This research is expected to provide more appropriate preventive strategies to extend the service life of the aircraft structure while maintaining both operational safety and efficiency.

The purpose of this research is to use the six sigma approach to assess the quality of cracker manufacturing at UD. Palapa in Nganjuk Regency. This technology was chosen because it allows for quantitative measurement and analysis of product defect levels, as well as the identification of defect-causing variables. The study was carried out using the DMAIC (Define, Measure, Analyze, Improve, Control) steps and statistical methods such as Pareto diagrams, fishbone diagrams, and C-chart control charts. According to the research, the cracker manufacturing process at UD. Palapa has an average sigma value of 2.74, which is still below the six sigma (6σ) threshold.  This figure implies that the product fault rate remains fairly high.  The most common forms of faults are irregular shape and uneven thickness, which are mostly produced by machine, human, process, and raw material problems. C-chart analysis reveals that most processes are still under control, while there are a few spots beyond the control boundaries that indicate unique variances. Based on these data, it is possible to infer that UD. Palapa's quality control system is still reactive and has to be improved in order to be more proactive. Routine equipment maintenance, operator training, the introduction of standard operating procedures (SOP), and more stringent raw material selection are all possible efforts. Six Sigma deployment has been shown to provide a full view of production quality conditions, as well as a foundation for future continuous improvement programs.

This study aims to analyze and improve the quality control of packaging printing production at PT XYZ by applying the Lean Six Sigma methodology. Lean Six Sigma combines waste reduction principles with statistical quality control to achieve operational excellence. The research identifies major production challenges, including high defect rates, overproduction, and ineffective inventory management, all of which contribute to increased costs and reduced efficiency. The DMAIC framework—Define, Measure, Analyze, Improve, and Control—was employed to systematically address these issues. During the Define and Measure phases, types of waste were identified and defect rates were calculated using Defects Per Million Opportunities (DPMO). In the Analyze phase, root causes were examined using a Fishbone (Ishikawa) diagram, highlighting factors related to manpower, materials, machines, and methods. The analysis revealed a sigma level of 3.2, indicating a moderate level of process quality and substantial room for improvement. To address the identified issues, several improvement strategies were proposed. These include implementing a Just-In-Time (JIT) system to reduce inventory waste, adopting the First-In-First-Out (FIFO) inventory method for better material rotation, and conducting targeted technical training for operators to minimize human error. In the Control phase, the study suggests process standardization, routine inspections, and continuous monitoring as key practices to ensure that improvements are sustained over time. The findings and recommendations from this study are expected to contribute to better quality control, reduced operational waste, and enhanced productivity in the packaging printing process. Ultimately, this approach aims to strengthen PT XYZ’s competitiveness in the printing industry by fostering a culture of continuous improvement and quality excellence.

This study aims to analyze the causes of component failure in the Power Train system of unit OHT773E CO2278 at PT. Cipta Kridatama, Samarinda, using the Root Cause Failure Analysis (RCFA) method. The Power Train system is responsible for transferring power from the engine to the final drive and other components, making it critical for the operational success of heavy equipment. Therefore, optimal maintenance is essential to prevent fatal failures that could impact the unit's performance. Based on the analysis, the dominant cause of failure is human factors, particularly technician negligence during component installation. This negligence results from a lack of understanding of the procedures and specifications recommended by the manufacturer, leading to incorrect installation of components. This failure impacts the achievement of the component’s expected lifetime, thus shortening the operational life of the components and increasing the risk of more severe damage. This also leads to higher repair costs and reduced unit productivity, resulting in longer downtime. To address this issue, several preventive measures are recommended, such as regular training for technicians to enhance their understanding of correct procedures and specifications, as well as the importance of following manufacturer guidelines during every maintenance and installation process. Additionally, it is advised to conduct routine discussions between technicians and supervisors to ensure that every maintenance step and installation complies with the established procedures. Increased oversight of the installation and maintenance process is also necessary, along with periodic rejuvenation of components to ensure the optimal performance of the Power Train system. Strengthening Preventive Maintenance (PM) practices is also crucial to minimize future damage potential. Implementing these solutions is expected to enhance the reliability of the Power Train system, extend component lifespan, and reduce failure frequency, ultimately improving the overall efficiency and productivity of the company.

Community diagnosis is a strategic step that aims to identify fundamental problems in the community, determine problem priorities, and formulate appropriate solutions to overcome them. One of the identified health issues is a significant increase in cases of mumps (epidemic parotitis), an acute infectious disease caused by the mumps virus, a member of the Rubulavirus genus. This increase in cases was recorded in the Puskesmas work area from the beginning of the year to November 2024. This phenomenon raises concerns regarding the potential for widespread health problems at the community level. Therefore, this intervention activity was carried out with the hope of reducing the incidence of mumps in the Puskesmas work area.The methodology applied in this activity includes data collection through mini surveys, analysis of health determinants using the Blum Paradigm, determination of problem priorities through the Delphi method, and identification of root causes using a fishbone diagram. Based on the results of this analysis, the interventions implemented include counseling on mumps and preventive measures, as well as demonstrations of proper hand washing. The results of the intervention showed a significant increase in knowledge, where all participants (n=40, 100%) obtained a post-test score of ≥ 7, indicating a good understanding of the material presented. In the demonstration session, a number of participants were also able to demonstrate the steps for washing hands according to the correct procedure. From the results of the analysis, it was found that the increase in mumps cases in this area was closely related to community lifestyle factors. Therefore, this intervention is expected to not only increase community knowledge about mumps, but also encourage the implementation of clean and healthy living behaviors, especially in the practice of washing hands, as a preventive measure to reduce the number of transmissions and accelerate case handling.

In the textile industry, quality control is a crucial aspect to ensure the stability and consistency of production results. One of the important stages in yarn production is the warping process, which has a significant influence on the quality in the subsequent process. This study aims to apply the Statistical Process Control (SPC) method to assess the quality of 40 CD KNB yarn in the warping process in the GKBI PC company, Preparation Department, and determine whether the process is already in a controlled condition. Currently, the average quality and amount of monthly yarn production show fluctuations with a downward trend of 1.64 per 5,000,000 meters in the period February–July 2024. This figure is below the company's daily production target of 1.00 per 5,000,000 meters, so the target has not been achieved. This discrepancy indicates the need for a more systematic evaluation and improvement of the quality control system. Based on the analysis of the X-Bar control chart in January 2025, two data points were found outside the control limits (UCL = 176.8; LCL = -29.5; average = 73.6), ie on January 4 and 20. The main cause of such uncontrollability is the weak yarn that comes from the rewinding process. Check sheet analysis and Pareto diagram shows that the most common factors causing thread breakage are weak threads. Furthermore, through the cause-and-effect diagram (fishbone diagram), it was identified that the factors that cause thread breakage come from four categories: human (HR), material (raw material), environment, and machine. Of the four factors, human resources and material aspects are the biggest contributors to influence. Therefore, it is recommended that quality control at PC GKBI be strengthened through training and counseling programs to employees, in order to improve skills and awareness of the importance of quality. This step is expected to reduce the rate of yarn breakage, maintain the stability of the production process, and ensure consistent achievement of company targets.

This study aims to analyze the effectiveness of preventive maintenance on the Simplex machine at PT. XYZ by applying the Overall Equipment Effectiveness (OEE) method and identifying the primary causes of production losses through the Six Big Losses framework. Preventive maintenance is an important strategy to ensure machine reliability, reduce downtime, and improve production efficiency. OEE is a widely recognized performance measurement tool consisting of three key indicators: Availability, Performance, and Quality. These indicators collectively reflect the overall effectiveness of equipment in supporting the production process. The results of this study indicate that the OEE value of the Simplex machine is 79%, which remains below the world-class benchmark of 85% as recommended by the Japan Institute of Plant Maintenance (JIPM). This finding suggests that the machine’s performance has not yet reached the optimal standard and requires improvement efforts. Further analysis using the Six Big Losses approach reveals that the most significant contributors to reduced machine effectiveness are equipment failure and idling or minor stoppages. These two categories account for the majority of productivity losses, thereby affecting both machine utilization and production output. To further explore the underlying issues, a root cause analysis was conducted using a fishbone diagram, which enabled the identification of several critical factors related to human resources, methods, machines, materials, environment, and measurement systems. Based on this analysis, improvement proposals were developed through the 5W+1H method, providing a systematic strategy to enhance preventive maintenance practices. The recommended actions include scheduling more frequent inspections, improving operator training, upgrading spare parts management, and implementing stricter monitoring of machine performance. In conclusion, this study highlights the importance of continuous preventive maintenance to optimize machine productivity and reduce unplanned downtime. By adopting the proposed improvement strategies, PT. XYZ can increase the effectiveness of its Simplex machine, moving

Tuberculosis (TB) is an infectious disease caused by infection with bacteria from the Mycobacterium tuberculosis complex group. TB prevention efforts are crucial, especially for individuals at high risk of exposure, to disrupt the chain of transmission of this disease. The intervention aimed to increase community understanding of TOSS TB (Find, Treat, Treat Until Cured) so that it can be applied in daily life. It is expected that after the intervention, participants' knowledge will increase, as will their ability to demonstrate the practices taught appropriately. Data collection was conducted through a mini-survey of the community in the local Community Health Center (Puskesmas) working area. The data obtained were then analyzed using the Blum Paradigm to identify factors contributing to the problem. Problem prioritization was carried out using the non-scoring Delphi method, while root cause analysis was conducted using a fishbone diagram. During the intervention process, pre- and post-tests were conducted to evaluate changes in the level of knowledge of villagers before and after the intervention. For program monitoring and evaluation, the PDCA (Plan-Do-Check-Act) cycle approach and a systems approach were used. The analysis using the Blum Paradigm showed that lifestyle was the primary contributing factor to the problem. After the intervention, three participants were able to repeat the material effectively, demonstrating a better understanding of TB prevention. Based on these results, it can be concluded that the intervention was successful and is expected to encourage improvements in public health in the village. Furthermore, this program is also expected to serve as a model for other public health interventions, thereby expanding the positive impact of TB control efforts in other areas. Thus, public awareness and knowledge about TB can continue to increase, which in turn will contribute to reducing TB incidence in Indonesia and improving the overall quality of life of the community.

Micro, Small, and Medium Enterprises (MSMEs) play a strategic role in Indonesia’s economy, including in the garment industry. The subject of this study is MSME X, located in Cimahi City, which specializes in the production of knitted clothing. This research aims to identify production problems, analyze the causes of defects, and design improvement strategies using the Six Sigma method with the DMAIC (Define, Measure, Analyze, Improve, Control) approach. In the Define stage, the main problems are identified through the Critical to Quality (CTQ) approach, which reveals three major types of defects: button defects (39%), stitching defects (32%), and fabric or pattern defects (29%). Next, the Measure stage is conducted to assess process performance using quality indicators. The calculation results show a Defects per Million Opportunities (DPMO) value of 10,968.95 and a Sigma Level of 3.79, indicating room for improvement. The Analyze stage utilizes Pareto and Fishbone diagrams to identify root causes. The Improve stage applies Failure Mode and Effect Analysis (FMEA) to determine improvement priorities. The Control stage involves the use of Statistical Process Control (SPC), regular inspections, and an incentive system. This approach is expected to reduce defect rates and sustainably improve production efficiency.

UD. Sarigut Bakery is known as one of several industries that focus on processing bread specifically in the Banda Aceh City area that seeks to produce with a variety of bread. The purpose of this study is to carry out efforts to identify, measure efforts, and analyzing efforts to the phase known to be the cause of the decline in quality of the production process of meses bread through a series of stages of the DMAIC SIX SIGMA methodology. It is known that the main problem is the discovery of disability with a total of 4,096 of the total production of the production of 21896 with a period of 3 months specifically in the dominant disability of Meses bread in the percentage of 81.29%. With the dominant of the disability itself the disability that comes in damaged bread with a percentage of 36.49% present from all of the total disability of related meses bread. After the assessment effort, the DPMO value was obtained by 26723.74 so that there were several levels of Sigma 3, which means it was still far from the world industry level which reached 6σ (3.4 DPMO). Efforts to analyze the data carried out by applying the Fishbone and FMEA (Failure Mode and Effect Analysis) diagrams are known to be related to the cause of the presence of disability from damaged bread with 3 modes of failure in potential, namely bread that is not filled with chocolate with a value of 20, the upper bread with a value of RPN of 80 and failure mode on broken bread with the highest RPN value of 90.

The research was conducted directly at the Pertamina Hulu Mahakam CPU Tambora Samarinda Company. The problem in this study is how to control the quality of wastewater and what factors affect the quality of wastewater in the PHM CPU Tambora Samarinda area, while the purpose of the study was to determine the control of wastewater quality and determine the factors that affect the quality of wastewater. Wastewater sampling was carried out in bottles for 31 days at 06.00 am and then sent to the laboratory for analysis of oil content in wastewater. The method used is the control map approach and fish bone diagram. The results of the study showed that the quality of wastewater was still within the standard quality limit of 12.5 ppm (still below the maximum standard of 40 ppm) and the dominant factor affecting the quality of wastewater was the equipment factor, namely due to damage to the pump

The research took place at Wastec Internasional Company, a company engaged in environmental waste processing services. The oil from the crude oil waste processing treatment process still has Basic Sediment and Water (BS&W) content and oil content that is too high so that it cannot reach the established standards so that the company must make efforts to reduce waste from the production process. The purpose of the study was to determine the sigma value, the number of defects and factors causing quality failure in crude oil processing treatment at PT Wastec Internasional. The methods used are the DMAIC method, control maps and fishbone diagrams. The calculation results obtained an average BS & W sigma value of 3.4 and an oil content sigma value of 3.29. The average number of defects for BS&W was 9.075% and for oil content was 2113 mg/L. The factors causing treatment quality failure are material, method and environmental factors.

The development of digital technology encourages MSME players to utilize digital platforms as a medium of information and communication with customers. Widasari Bakery is a bakery established since 1999 in Sidoarjo, has not maximized digital platforms such as websites as information media. This study aims to design the interface design of the Widasari Bakery website as a medium of information and communication to customers. The research method used uses qualitative and quantitative methods involving surveys, interviews, questionnaires, and literature studies, and uses the fishbone diagram method and SWOT analysis to identify problems and look for development potential. The results of this design are expected to increase brand identity and market reach and strengthen the growth of the Widasari Bakery brand in the digital era.

The rapid increase in Ro-Ro (Roll-On/Roll-Off) vessel and vehicle traffic at Tanjung Perak Port, Surabaya, has exposed critical inefficiencies in port operations, particularly at key berths such as Jamrud Utara and Jamrud Selatan. These inefficiencies manifest as prolonged queuing times for Ro-Ro vessels and land-based vehicle congestion, leading to delays in cargo handling and increased operational costs. This study aims to evaluate the operational performance of Ro-Ro terminals based on queue time indicators for both Ro-Ro vessels and vehicles. Employing a quantitative descriptive approach, the research integrates the M/M/c queuing model and Fishbone Diagram analysis to identify systemic causes of operational delays and overcapacity. The study reveals that berth utilization rates exceed 75%, indicating saturation, while limited buffer zones and disorganized traffic flow exacerbate vehicle queues. As a case study, the findings offer data-driven insights and practical recommendations, including schedule optimization, dedicated traffic lanes, and infrastructural upgrades to mitigate congestion. The proposed framework not only enhances service efficiency at the port but also contributes to broader logistics performance in Eastern Indonesia. By combining classical queuing theory with root cause analysis, this research introduces a methodological synergy that can be replicated across other Ro-Ro terminals facing similar challenges. The findings underscore the urgent need for integrated port traffic management and infrastructural adaptability in response to growing maritime logistics demands.