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Water heating systems on ships play a crucial role in supporting crew comfort and operations. However, conventional systems generally operate continuously without automatic control, resulting in energy waste and high operational costs. This situation drives the need for innovation in more efficient and environmentally friendly water heater designs. This research aims to design and implement an automated water heater temperature control system based on an ESP32 microcontroller with on/off control and the use of paraffin wax as a latent heat storage medium. This design is expected to improve energy efficiency while reducing the operational costs of water heaters on ships. The research methodology includes system design, hardware assembly, and performance testing, both static and dynamic. Testing was conducted to evaluate temperature stability and energy efficiency in system conditions with and without the use of paraffin wax. The results showed that paraffin wax improved water temperature stability while reducing the frequency of heater activation. In a 24-hour test, the system without paraffin wax recorded a heater operating time of 15 hours, consuming 8.85 kWh of electricity and costing Rp11,965.20. In contrast, the Paraffin Wax system only requires 10 hours of heater operation, consumes 5.90 kWh, and costs Rp7,976.80. This demonstrates energy savings of 2.95 kWh and a cost efficiency of up to 58%. Therefore, the ESP32-based water heater automation system and heat storage using Paraffin Wax are proven to be more energy-efficient, cost-effective, and have the potential to be an innovative and environmentally friendly solution for ship operational needs.

This study proposes the integration of a Hybrid Recommendation method (combining Content-Based and Collaborative Filtering) with Random Forest Regression (RFR) to improve the accuracy of stay duration prediction in web-based boarding house booking systems. The main issue in online boarding booking systems is the inaccuracy of predicting user stay duration, affecting room allocation efficiency and customer satisfaction. The dataset was sourced from the hotel sector due to its attribute similarities and data validity. The research process includes data preprocessing (missing value imputation, normalization, and one-hot encoding), temporal and contextual feature engineering, hybrid recommendation system construction with CBF and CF score weighting, and RFR model training optimized through Grid Search and 10-fold cross-validation. Evaluation was conducted using MAE, RMSE, R² metrics, as well as recommendation metrics such as Precision@5, Recall@5, and Mean Reciprocal Rank (MRR). Results show that this integrated model achieved an R² of 0.7239 and an MAE of 1.0537 days, as well as a Precision@5 of 0.9636. This integration proves effective in improving prediction accuracy and recommendation relevance and contributes to the development of AI-based intelligent systems in the accommodation domain.

This study presents a modal analysis of Pertamina EP Cepu’s closed drain pump 510-P9002, which operates in the condensate–water treatment unit of the Jambaran Tiung Biru field. Field vibration measurements conducted in August 2024 indicated a fundamental frequency of 25 Hz, corresponding to 1×RPM of the driving motor, with maximum amplitudes reaching 13.46 mm/s. Such excessive vibration poses risks of mechanical damage, reduced equipment service life, and potential operational failure. To address this issue, finite element analysis (FEA) was employed to examine the dynamic response of the pump, determine its natural frequencies, and identify possible resonance conditions. A CAD model of the pump–vessel assembly was developed, meshed, and analyzed under actual boundary conditions. The results showed several natural frequencies ranging between 23.16 and 26.65 Hz, which are close to the excitation frequency, suggesting a very high likelihood of resonance. Various structural modifications were then evaluated, including a half casing and two types of full casings. Among these, the full casing B design provided additional stiffness in the motor support area; however, none of the modifications effectively reduced vibration within the internal components. Based on these findings, the study recommends the implementation of a dynamic vibration absorber (DVA) tuned to the excitation frequency, along with the redesign of structural components to shift natural frequencies away from operating excitation. These solutions are expected to improve operational stability, extend equipment lifespan, and enhance overall system reliability. The outcomes of this research provide important insights for managing vibration issues in pump systems operating under similar conditions, particularly in the oil and gas industry where continuous, stable operation is critical.

The Sugio–Tlanak Road Section, Sugio District, Lamongan Regency, is a vital transportation infrastructure as it connects interregional activities, both in economic, social, and community mobility aspects. This road is the main route used by various types of vehicles, from light vehicles to heavy vehicles with quite high traffic intensity. This condition has a significant impact on the quality of the road pavement, as indicated by the presence of various types of damage at several points, such as cracks, potholes, and road surface deformation. Therefore, a comprehensive evaluation is needed to determine the level of road damage as a basis for consideration in planning maintenance and repairs. This study uses two assessment methods, namely the Bina Marga method and the Pavement Condition Index (PCI). The Bina Marga method assesses road conditions based on the Surface Distress Index (SDI) value obtained from direct identification in the field. The evaluation results show that the road condition on the Sugio–Tlanak section is classified as severely damaged at 60%, moderately damaged at 30%, and good condition at only 10%. Meanwhile, the PCI method provides results in the form of more detailed quantitative values. The analysis results obtained an average PCI score of 58.6, which is included in the Fair category. A comparison of the two methods shows that the Bina Marga method has advantages in terms of speed and ease of implementation, but its assessment is relatively subjective. In contrast, the PCI method provides more accurate and measurable results because it uses a quantitative approach with clear damage condition parameters. Therefore, although the Bina Marga method can still be used for rapid assessments in the field, the PCI method is more recommended as a basis for technical decision-making in planning road maintenance and quality improvement programs.

The increase in traffic volume in urban areas often triggers various problems, especially at Road intersection points that have a high level of interaction between vehicles. One of the locations that experience these problems is the intersection with the island of traffic without signal on Jl. Tebu-Jl. Tabrani Ahmad, City Of Pontianak. This study aims to analyze the performance of the intersection in the existing condition and project its performance in the next five years (2030), as well as formulate alternative treatment that can improve the smoothness of traffic. The analysis method refers to Indonesian road capacity guidelines (PKJI) 2023 and modeling using software PTV VISSIM. The data collected include intersection geometry, traffic volume, and vehicle speed. Traffic volumes were obtained through CCTV recordings for three consecutive days, then processed and presented in the form of tables and graphs for easy interpretation. The results of the existing condition analysis showed that the degree of saturation (DS) reached 0.407 with an average delay of 9.539 seconds (Level of Service/LOS B) based on PKJI, while VISSIM simulation resulted in a delay of 12.54 seconds (LOS B). The five-year projection (2030) shows an increase in DS to 0.878 with a delay of 15.177 seconds (LOS C) from PKJI, and 23.35 seconds (LOS C) from VISSIM, which indicates a decrease in Junction performance as traffic grows. Two handling alternatives were analyzed, namely the construction of roundabouts and the implementation of traffic flow management. VISSIM simulation shows that the roundabout can reduce the delay to 14.31 seconds with a queue length of 20.34 m (LOS B), while the flow management produces a delay of 11.81 seconds with a queue of 13.14 m (LOS B). This result confirms that both alternatives are able to improve the performance of the intersection compared to the projected condition without handling, so that it can be a technical recommendation for urban traffic planning in Pontianak.

Distribution is an important aspect that affects the operational efficiency of a company, especially in terms of goods delivery. This study aims to develop an optimization model for LPG gas distribution routes using Excel Solver based on geographic coordinate conversion. In this study, the method used includes converting geographic coordinates from decimal to Degree-Minute-Second (DMS) format, followed by conversion to kilometers to form a more accurate distance matrix. The optimization model was built using the Capacitated Vehicle Routing Problem (CVRP) approach, which takes into account vehicle capacity constraints (a maximum of 560 cylinders per truck) and the limited number of available fleets, which is only one truck. The results show that coordinate conversion produces high accuracy in calculating distances between distribution locations. By using Excel Solver, the optimization solution successfully minimizes the total distance traveled compared to the conventional route, where distribution is carried out more evenly to 57 scattered LPG base locations. The addition of Solver Parameters Evolutionary and All Different constraints proved effective in avoiding duplication of visits and producing optimal distribution routes. This solution not only improves distribution time and cost efficiency, but also improves service to customers by reducing delivery delays. The success of this optimization model is expected to be implemented by other distribution companies to improve their operational performance. This study also highlights the importance of selecting the right software to aid the distribution optimization process. Excel Solver, despite its simplicity, proved highly effective in solving complex distribution routing problems, especially when combined with coordinate conversion techniques that yield more accurate distances. Furthermore, the application of the CVRP method enabled more efficient decision-making in determining distribution routes, taking into account vehicle capacity and fleet limitations.

This study also highlights the importance of education and training for farmers to improve their technical skills in farming and managing their farms. Training in the use of modern agricultural technologies, such as automated fertilizing tools and efficient irrigation systems, can help farmers reduce production costs and increase yields. Furthermore, training in digital marketing can help farmers market their products more effectively through online platforms, reducing reliance on intermediaries and increasing profit margins. Furthermore, it is crucial for the government to provide support in the form of extension services and easy access to business capital. More accessible capital will enable farmers to invest in more efficient equipment and more environmentally friendly organic fertilizers. Targeted microcredit distribution to farmer groups can also accelerate the adoption of new, more productive agricultural technologies. The adoption of sustainable and environmentally friendly agricultural practices should be a long-term focus to ensure the registration of shallot farming businesses. Farmers need to be incentivized to use organic fertilizers and natural pesticides that are safer for the soil and air. Furthermore, the implementation of integrated and environmentally friendly farming systems such as agroforestry can also be an alternative to increase agricultural yields without damaging the environment. With improvements in education, training, access to capital, and the adoption of more efficient technology, shallot farming in Pasir Village can develop better and become more sustainable in the future. Furthermore, collaboration between farmer groups and local research institutions and universities can also be key to introducing new agricultural innovations.

This study is motivated by the downstream Teh Walini industry’s reliance on third-party logistics (3PL) services for product distribution, which restricts the company’s control over several key aspects, including logistics costs, delivery speed, routing efficiency, and product handling quality. The primary objective of this research is to analyze and compare distribution costs between outsourced logistics and self-managed delivery, and to evaluate the potential cost efficiency of an independently operated shipping system. A descriptive comparative quantitative method is employed, incorporating movement generation analysis, distribution spread mapping, and Vehicle Operating Cost (VOC) calculations to estimate the cost implications of self-shipping. Data were obtained through company documentation and analyzed using multiple linear regression involving six major distribution points. The results reveal that shipment volume significantly influences movement generation, with Waingapu, Makassar, and Padang identified as the dominant distribution destinations. The cost comparison analysis demonstrates that self-managed delivery is more cost-effective than third-party logistics services, making it a more viable long-term option. These findings suggest that transitioning to a self-delivery system could improve cost control and logistical efficiency for the company. However, this strategy should be implemented gradually, supported by regular updates on operational cost data and proactive management of external factors that could impact distribution performance. The study concludes by recommending broader coverage and the inclusion of additional relevant variables in future research to further validate and enhance decision-making related to distribution strategies. A well-informed shift toward internal logistics could ultimately contribute to greater competitiveness and sustainability in the company’s distribution operations

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.

UMKM Tahu XYZ, a small-scale tofu producer, is currently facing significant challenges in maintaining consistent product quality, primarily due to a high defect rate. Common issues identified include crumbled tofu shapes, overly soft textures, and inconsistent taste, which negatively impact customer satisfaction and business sustainability. This study aims to investigate the root causes of these quality issues and propose practical solutions using the Lean Six Sigma methodology. The research employs a descriptive quantitative approach through the DMAIC framework—Define, Measure, Analyze, Improve, and Control—to ensure systematic problem-solving. Data were collected over a six-month period through direct observation, structured interviews, and review of production records. The analysis identified four dominant types of waste within the production process: unnecessary transportation, product defects, excessive movement, and over-processing. The root causes of these inefficiencies are linked to poor handling of raw materials, variability in soybean quality, and an ineffective production layout that hampers workflow and consistency. To address these problems, the study proposes several targeted interventions, including the redesign of the production layout to optimize flow, the implementation of the 5S (Sort, Set in order, Shine, Standardize, Sustain) workplace organization method, the development of standardized operating procedures (SOPs), and the adoption of improved soybean boiling technology. The implementation of these improvements is projected to significantly reduce product defects, enhance process efficiency, and ultimately increase customer satisfaction. Furthermore, these actions are expected to improve the overall competitiveness of UMKM Tahu XYZ within the highly demanding food industry sector. This research provides actionable insights for other micro, small, and medium enterprises (MSMEs) seeking to apply structured quality control methods to strengthen operational performance and long-term business resilience.

Mail management in higher education institutions, particularly at the Nurul Fikri Integrated Technology College (STT), is still carried out manually or conventionally. This process involves physically recording and distributing letters, which in practice often creates various obstacles. Some common obstacles include the long time required to manage letters, the risk of document loss or damage, and the high possibility of errors in letter numbering. Furthermore, the document validation process is also less effective due to the lack of a system that supports electronic signatures or digital verification of document authenticity. Based on these conditions, this study aims to design and develop a digital system that can help manage letters more efficiently and securely. This system is designed not only to speed up the administrative flow of correspondence but also to simplify the document validation process through the application of digital technology. Thus, this system is expected to reduce administrative errors, increase work efficiency, and ensure the security and validity of official documents. The method used in this study is Design Thinking, which consists of five main stages: empathize, define, ideate, prototype, and test. This approach enabled researchers to deeply understand user needs, explore various alternative solutions, and create an intuitive and user-friendly interface design for all parties involved in the administrative process. The research results showed that the designed system can accelerate the administration process for official letters and documents. The embedded superior features include digital validation and electronic signatures integrated with QR Code technology, thus providing a higher level of transparency and security in document management within the university environment.

Floods are one of the most common natural disasters and have a significant impact on the social, economic, and environmental aspects of society. This is particularly evident in the community of East Sorong District. East Sorong District is one of the areas frequently affected by floods, and this inevitably leads to numerous risks and consequences. There are several causes of flooding in the Sorong Timur District, including extreme rainfall, inadequate drainage systems due to trash blockages, uncontrolled land use changes resulting in overpopulation, and the loss of forest areas or green spaces that could function as water absorption zones. Additionally, the lack of flood control systems and weak oversight of development in flood-prone areas can exacerbate flood disaster risks. This study aims to analyze and measure the resilience of the Sorong Timur District in facing flood disasters through an evaluation approach focusing on infrastructure, service facilities, socio-economic factors, community capacity and preparedness, and institutional aspects. It was concluded that the infrastructure variable is still moderate, while the socio-economic variable, basic capacity, and community preparedness, as well as institutional capacity, are still low. Meanwhile, service facilities are also low. Overall, it can be concluded that the resilience of the Sorong Timur district in facing hydrometeorological disasters is weak.

Increasing business competition requires companies to consistently improve quality and operational efficiency. This study aims to identify and reduce non-value added activities in the procurement process at Distributor X, a company engaged in the distribution of instant cooking spices. Common issues include expired goods (49.05%), damaged packaging (18.78%), and product mismatches (32.17%). The Lean Six Sigma approach with the DMAIC (Define, Measure, Analyze, Improve, Control) method is used to address these problems. Measurement results show an average DPMO value of 10,076.58 and a sigma level of 3.82, which are still far below the Six Sigma quality standard. Improvement proposals include the implementation of barcode/RFID systems, FIFO inventory management, higher-quality packaging materials, and the use of unique product codes. In the Control phase, monitoring is carried out through an ERP system and the establishment of structured SOPs to support distribution oversight. This approach demonstrates potential in reducing defect rates and improving the overall quality of the procurement process.

Holtekamp Beach is a coastal area in Jayapura City that is very prone to abrasion due to sea waves because it is located directly opposite the Pacific Ocean. Abrasion and environmental damage on the coast of Holtekamp Beach are influenced by several interconnected factors that can have an impact on environmental problems. The research aims to analyze the impact of abrasion on the Holtekamp coastal area using survey and interview methods. Furthermore, data analysis is carried out by utilizing SWOT Analysis. This research was conducted from May to June 2025. The results showed that there are 4 (four) priority strategies that can be used as a basis for developing a strategy for Abrasion Disaster Risk Management Strategy in the Holtekamp Coastal Area of Jayapura City, namely; a) Increasing cooperation & coordination between stakeholders, namely the community and local government in achieving abrasion disaster management programs in the Holtekamp Coastal Area of Jayapura City; b) Optimizing supervision of development development/tourist lodges in the coastal area of Holtekamp Beach; c) Community participation is needed to maintain infrastructure that has been built and increase their awareness of environmental issues.d) Construction of wave breakers that function to reduce waves.

The spice industry faces significant challenges in maintaining product weight consistency as part of quality assurance and compliance with production standards. A case at PT X revealed that a newly installed filling machine produced deviations from the target weight of 50 grams, with hypothesis testing showing that out of 30 samples, 17 samples fell outside the  confidence interval. To mitigate this issue, this study proposes the development of a real-time data-driven Decision Support sistem (DSS) combined with statistical approaches. The methodology includes two-tailed hypothesis testing to detect weight deviations and Failure Mode and Effects Analysis (FMEA) to identify dominant failure causes based on high Risk Priority Numbers (RPN), such as delayed machine calibration, operator error, and worn-out machine components. These findings serve as the foundation for designing the DSS architecture, which consists of sensor input modules, statistical data processing, risk mapping, and an automated corrective recommendation engine. The sistem is designed to enable early detection of deviations, accelerate response time to quality issues, and support data-driven decision-making on the production floor. The study concludes that a structured implementation of DSS can be an effective strategy to improve product weight consistency and enhance operational efficiency in spice manufacturing.  

Quality assurance is a crucial foundation for universities to ensure quality, accountability, and sustainable governance. Digital transformation in higher education quality governance requires an efficient, informative, and easy-to-use system. This study aims to design a prototype dashboard for an Internal Quality Assurance Information System based on user needs using the Design Thinking approach with a case study of the Sekolah Tinggi Teknologi Terpadu Nurul Fikri. The research process involves five main stages: Empathize, Define, Ideate, Prototype, and Test. Data was collected through interviews with quality assurance unit personnel and analyzed to formulate visual solutions that address user needs. The dashboard prototype was tested using the User Experience Questionnaire (UEQ) method and yielded positive scores across all dimensions, particularly clarity and stimulation. These results indicate that the developed design is capable of providing an effective user experience in supporting the implementation of the internal quality assurance system.

Skin that is prone to bacterial infections requires proper care using products containing antibacterial agents. One potential alternative is kaffir lime leaves (Citrus hystrix), which are known to contain antibacterial compounds. This study aimed to evaluate the formulation of liquid soap containing kaffir lime leaf extract and to determine the optimal concentration for inhibiting bacterial growth. An experimental laboratory design was applied, and the antibacterial effectiveness was tested using the disk diffusion method against two test bacteria, namely Staphylococcus aureus and Escherichia coli. Statistical analysis was performed using One-Way ANOVA, followed by Scheffe’s post-hoc test to identify significant differences among treatment groups. The results indicated that the liquid soap containing kaffir lime leaf extract exhibited good physical quality and met standard parameters, including organoleptic evaluation, pH, viscosity, and foam height tests. Antibacterial testing showed that the highest inhibition zone against Staphylococcus aureus was observed at a 15% concentration with a zone diameter of 18.28 mm (strong category), while the highest inhibition zone against Escherichia coli was also at a 15% concentration with a diameter of 19.03 mm (strong category). The One-Way ANOVA results showed a significance value (p < 0.05), indicating a statistically significant difference among treatments for both bacterial species. These findings suggest that liquid soap formulated with kaffir lime leaf extract, particularly at a 15% concentration, has strong antibacterial activity and potential as an effective skin care product. Further studies are recommended to evaluate safety, stability, and long-term effectiveness.

Anxiety is an emotional condition that causes feelings of discomfort, helplessness, and uncertainty, often without a clear reason. Among breast cancer (carcinoma mammae) patients, anxiety commonly arises due to treatment processes, physical changes, and uncertainty regarding recovery. Spirituality, which involves belief in God Almighty and connection with transcendental aspects, is believed to help individuals cope with uncertain and challenging situations, including serious illness. This study aimed to determine the relationship between spiritual level and anxiety level among breast cancer patients in Semarang. The research used a quantitative correlational design with a sample of 110 respondents selected through purposive sampling based on inclusion criteria. The instruments employed were the Depression Anxiety Stress Scale (DASS-42) to assess anxiety levels and the Daily Spiritual Experience Scale (DSES) to measure spirituality. Data were analyzed using the Chi-Square test to examine the relationship between variables. The results showed a p-value of 0.000 (p < 0.05), indicating a significant relationship between spirituality level and anxiety level in breast cancer patients. The findings suggest that higher levels of spirituality are associated with lower anxiety levels. Therefore, interventions that support and strengthen spiritual aspects may be effective in reducing anxiety among breast cancer patients. This study recommends that healthcare professionals incorporate spiritual approaches as part of holistic care to improve psychological well-being in patients undergoing cancer treatment.

          During the second and third trimesters of pregnancy, as fetal development progresses, pregnant women often experience lower back pain. This condition not only causes discomfort but also affects daily activities and overall quality of life. One of the non-pharmacological approaches believed to reduce lower back pain is prenatal exercise. This study aims to evaluate the effect of pregnancy exercise on reducing lower back pain among pregnant women in the second and third trimesters. This research employed a quasi-experimental design with a pre-post test approach without a control group. The sample consisted of 28 pregnant women in their second and third trimesters who met the inclusion criteria and reported experiencing lower back pain. Pain levels were assessed before and after the intervention using a valid and reliable pain scale. Data were analyzed using appropriate statistical tests, particularly the paired sample t-test. The findings revealed that the mean pain score before the intervention was 3.32 with a standard deviation of 0.772. After the intervention, the mean pain score decreased to 2.25 with a standard deviation of 1.005. Results of the paired t-test indicated a p-value of 0.000 (p < 0.05), demonstrating a significant difference in pain levels before and after pregnancy exercise. These results indicate that pregnancy exercise is effective in reducing lower back pain in women during the second and third trimesters of pregnancy. Therefore, prenatal exercise can be recommended as a safe, simple, and beneficial non-pharmacological intervention in midwifery care. It is expected that this study provides scientific evidence supporting the role of pregnancy exercise in improving maternal comfort and quality of life throughout pregnancy.

BPR in Indonesia. This study uses qualitative research methodology.  The methodology employed is a case study.  The findings of this investigation include (1) Marketing communication strategies in increasing customer loyalty at BPR Kusuma Sumbing Delanggu are by using 1) advertising, BPR Kusuma Sumbing Delanggu utilizes digital media, only using Facebook, Instagram and the BPR Kusuma Sumbing Delanggu website. 2) sales promotion, promotions using distributing brochures, installing banners, personal and non-personal sales by visiting customers directly. 3) Public relations, BPR Kusuma Sumbing Delanggu is building a positive image of the company through events, sponsorships, or CSR. 4) digital media promotion, digital media used in marketing BPR Kusuma Sumbing Delanggu uses social media such as Instagram and Facebook, and we also have a special website for BPR Kusuma Sumbing Delanggu with the website address. (2) BPR Kusuma Sumbing's challenge is that educational communication regarding BPR Kusuma Sumbing Delanggu products to customers is sometimes hampered by a lack of understanding of financial literacy. Therefore, I have to explain in detail and coherently, which takes quite a long time. (3) The solution to addressing the challenges in marketing communication strategies to increase customer loyalty at BPR Kusuma Sumbing Delanggu is to continuously improve customer relationships and expand our reach. By strengthening communication and providing better education, we believe we can increase customer loyalty and the BPR's future growth.