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Wheelchairs are tools for humans who experience illness, disabilities, and injuries that cause walking difficulties. There are many types of wheelchairs on the market, while wheelchairs that function to help users defecate flexibly have not been widely sold in the market. Therefore, it is necessary to develop a flexible and multifunctional wheelchair that can assist the users in carrying out their activities. This study aims to develop a design of the multifunctional wheelchair. The designing of multifunctional wheelchair based the FAHP (Fuzzy Analytical Hierarchy Process) method. The use of the FAHP was to select the optimal design and selection of the best alternatives among wheelchair’s indicators of design proposed. The results of calculation of weight values for wheelchair design were obtained a percentage of alternative 1 of 48% and alternative 2 of 52%.

This paper aims to identify waste and analyse production process activities using the Value Stream Mapping (VSM) in a small business as a case study. The waste was identified by a waste relationship matrix and waste assessment questionnaire to determine the percentage of waste that occurs. Furthermore, a detailed selection of waste mapping based on the value stream analysis tool was carried out. Based on the VSM analysis, it was found the value added activities of 59% of the total production time and 41% of other activity times (non value added). In the case study occurred the waste for the operator's work method at the station of printing and cutting station. The VSM was performed to reducing the waste. The result depicted reduction in lead time on the production floor was 1.5 hours. So, the company in the case study can eliminate the waste time in their production process activities

Developing an appropriate performance measurement system to foster continuous improvement can be challenge due to the company’s strategy and diversity of characteristics. This paper aims to develop performance measurement systems (PMS) for productivity enhancement of a particularly lean company or organisation. The PMS is based on multiple indicators decision making (MIDM) and uses the fuzzy analytical hierarchy process (FAHP). The hierarchical levels by choosing the perspectives and indicators were employed the fuzzy vagueness and uncertainty in human judgment into crisp scores from pair-wise comparison as decision making. Hierarchical mechanisms and multiple indicator of performance can create a link between tactical operational processes and strategic levels. It may assist a company in terms of measuring progress toward its goals, allowing decisions to be made regarding strategic management and operational activities, which will lead to continuous improvement. The PMS framework accommodates the company’s performances to enhance their productivity. A case study was performed to explore the applicability and potential strength of the lean PMS model.

This study discusses determining the optimal scheduling for maintenance of gas turbine engines in PLN Tanjung Datuk Pekanbaru. The optimal maintenance scheduling is done on critical components, namely turbine blade and AVR (Automatic Voltage Regulator) using Monte Carlo simulation. The optimal scheduling maintenance scenario is done by generating random numbers from MTTF (Mean Time To Failure) and MTTR (Mean Time To Repair) values and data validity testing. The results of research for optimal checking of turbine engines are once every 10 days with the reliability of turbine engines 43%. The optimal time for repairing a gas turbine in case of damage is 1.49 hours. The checking time for critical components of the turbine blade is 9 days and AVR of 12 days. The scenario of preventive maintenance is likely need special repair or replacement periodically that is 117 days for turbine blade components and 173 days for AVR.

The purpose of this study is to identify, analyze and evaluate the influencing of defects factors at the crusher knife reconditioning process in PT Andritz Pekanbaru. In this research adopted the Quality Control Circle (QCC) method. The QCC method is a quality control that is focused on the process of Plan, Do, Check, Action (PDCA). The research was carried out with 8 stages of PDCA, namely determining the theme, determining the title, finding the source of the problem, solving the problem plan, implementing, evaluating, standardizing, and determining the next plan. After observing the crusher knife reconditioning process, there were 10 defects that occurred in the crusher knife reconditioning process, which were porosity of 673 cases, curling tip of 78 cases and 57 of fewer cases followed. The repairs were carried out using the QCC method. The results of improvements were proved by reducing of the percentage of total defect porosity from 13% to 2%. Therefore, the repairs were successfully implementation, which decreasing of the defect porosity of 11%.

In this study, the effects of three different types of materials of post-cooling pipes on thermal stress and temperature gradients in mass concrete were investigated numerically. It was found that, of the three types of cooling pipe materials observed in this study, steel pipes caused the fastest cooling and the lowest concrete temperature, followed by polyethylene (PEX) and polyvinyl chloride (PVC) pipes. The temperature difference only occurs at locations less than 100 m from the cooling water inlet. The concrete temperatures obtained using a steel cooling pipe can reach temperatures 70% and 36% lower than those obtained using PVC and PEX cooling pipes, respectively. Compare to PEX and PVC cooling pipes, the steel cooling pipe can reduce the risk of cracking associated with the expansion of the core region and the shrinkage of the surface of the concrete. However, the steel cooling pipe increases the risk of cracking near the cooling pipe, where the tensile stress that occurs due to the use of steel pipes can reach values 25.3% and 12.7% higher than those occurring due to the use of PVC and PEX pipes, respectively. In high temperature regions, expansion of PEX and PVC pipes causes an increase in thermal stress, especially in the area near the cooling pipes.

One of the most commonly used geospatial mapping methods is photogrammetry (aerial mapping). Photogrammetry is a method of mapping objects on the surface of the earth by using aerial photography as a medium. The aerial mapping process is carried out through cameras installed on Unmanned Aerial Vehicle (UAV). From the aerial photography, object interpretation and geometry measurements will be carried out to produce line maps, digital maps and photo maps. In general, photogrammetry is a mapping technology by utilizing aerial photography to be processed into a geo-spatial information system. Batu Bersurat Village is one of the villages located in Subdistrict XIII Koto Kampar, Kampar Regency, which did not have a geospatial information map. Community service team from the Mechanical Engineering Department of the University of Riau had a plan to carry out community service activities in Batu Besurat Village in the form of making geospatial information maps through aerial mapping. This aerial mapping activity was carried out by utilizing UAV with the type of fixed wing. In its implementation, the community service activities were planned to involve Mechanical Engineering students, university students of the University of Riau, village officials and the local community. It is expected that with this community service program, the geospatial information system map made by Batu Bersurat Village can be used in village spatial planning for agricultural land, residential land and validation of village boundaries.

The eliminate wastes in manufacturing processes can be reinforcement for achieving sustainable manufacturing industry. This paper proposed to develop a framework to analyze an Overall Equipment Effectiveness (OEE) implementation to eliminate wastes for productivity improvement, and it’s correlated to sustainability in manufacturing Industry. An analyze wastages in term OEE is used the six big losses i.e. equipment failure, setup and adjustment loss, idling and minor stoppage, reduced speed, defects in process and reduced yields. The framework employed the Fuzzy AHP (Analytic Hierarchy Process) based OEE measurement. The case study from a crude palm oil manufacturing company was presented to strengthen the proposed method. Therefore, the framework can assist the top management in the company to decide the priorities to increases productivity and it’s correlated to manufacturing sustainability.

Hydration heat trapped in concrete can cause cracks due to thermal stress caused by temperature gradient inside the concrete. The trapped heat can be removed by using a post-cooling system, where the concrete is cooled by running water through pipes embedded in it. However, post cooling may cause thermal stresses owing to the temperature gradient in the region adjacent to the cooling pipe. In this study, the thermal stress and temperature gradient caused by the space between the cooling pipes and cooling water temperatures of the post-cooling system are investigated numerically. Based on the concrete type, thermal properties and dimension of post cooling components used in this study, it was found that, compared to cooling water temperature, the space between the cooling pipes had a stronger effect on the distribution of temperature and thermal stress in the concrete. The increase in cooling water temperature tend to increase concrete temperature and decrease thermal stress especially in region next to cooling pipe, while the increase in distance between cooling pipe tend to increase both of concrete temperature and thermals thermal stress near the cooling pipes. To reduce the risk of concrete cracking due to post cooling, it is not enough just to adjust the temperature of the cooling water and space between cooling pipes. The cooling water temperature, space between cooling pipe and convection coefficient from surface of cooling pipes to cooling water need to be set to obtain a temperature distribution which result a thermal stress which lower than tensile ultimate strength of the concrete.

For companies that implement Lean Manufacturing, it is essential to measure the extent of success in terms of the achievements of optimum performances. This paper describes the development of a Fuzzy Analytical Hierarchy Process (FAHP) algorithm based Performance Measurement System (PMS) application software for lean companies. The PMS software, which was developed using the C++ language, was designed as a decision making system to aid lean manufacturing companies. The software allows decision making analysis based FAHP facilitating data input, pairwise comparisons, weight calculation and lean company scores. A case study of a lean manufacturing is presented to illustrate the theoretical and practical aspects of the PMS software. The case study demonstrated the software tool can assent to a lean company to implement PMS in a much easier manner yielding more accurate and consistent results that include a list of recommended actions to address issues identified. Therefore, it can improve the company performance.