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This study aims to evaluate the level of heavy metal pollution and the potential ecological and human health risks in the waters of Selangan, Bontang City. The research focuses on analyzing the concentrations of iron (Fe) and mercury (Hg) in sediment, considering that both elements are toxic, persistent, and capable of bioaccumulating within the food chain. The study was conducted over six months, from January to June 2023, at four sampling stations representing the environmental conditions of Selangan waters. The methodology included sediment sampling, sample preparation through drying and grinding, and laboratory analysis using Inductively Coupled Plasma–Optical Emission Spectrometry (ICP-OES) to determine Fe concentrations. The results were then compared with quality standards established by the Washington Annotated Code 173-204-320 and Indonesia’s National Agency of Drug and Food Control (BPOM) Regulation No. 5 of 2018. The findings indicate the presence of heavy metal contamination across all sampling stations. Fe concentrations ranged from 2.35 mg to 6.308 mg, significantly exceeding the permissible limit of 0.3 mg/L. Meanwhile, Hg concentrations ranged from 0.015 mg to 0.028 mg, also surpassing the standard threshold of 0.001 mg/L. These results clearly demonstrate heavy metal pollution in the Selangan waters, posing potential threats to marine ecosystem health and coastal communities. Regular monitoring and mitigation measures are urgently recommended to prevent further environmental degradation.

This research focuses on optimizing the control system to improve voltage stability in a 10 kW Solar Power Plant (PLTS) located in a tropical region. The main issue addressed is voltage fluctuation caused by the intermittent nature of solar radiation (200–1200 W/m²) and temperature variations (20–50°C), which result in up to 12% overshoot in the inverter. The proposed method implements a Proportional-Integral-Derivative (PID) controller optimized using the Particle Swarm Optimization (PSO) algorithm with real-time irradiation input data. The research integrates a 100 Hz digital low-pass filter to mitigate sensor noise under low irradiation conditions. Simulation results show that the PID-PSO system successfully reduces overshoot from 12.1% to 4.2% under high irradiation, and decreases settling time from 0.62 seconds to 0.31 seconds. The digital filter effectively reduces measurement deviation from 7.2% to 2.8% at 200 W/m² irradiation. The PSO optimization achieved optimal convergence within 37 iterations with an Integral of Time-weighted Absolute Error (ITAE) value of 0.18. This study concludes that the implementation of PID-PSO with a digital filter significantly enhances the voltage stability of the PLTS by 20.3% compared to conventional PID control and is ready to be applied in tropical-region smart grid systems.

This study aims to examine pragmatic aspects, particularly speech acts and implicatures, in the lyrics of the song “Sedia Aku Sebelum Hujan” by Idgitaf. By applying a qualitative descriptive method through pragmatic content analysis techniques, this study examines locutionary, illocutionary, and perlocutionary speech acts based on Austin's theory, as well as conversational implicatures based on Grice's framework. The results show that the song lyrics are dominated by expressive and commissive illocutionary acts that serve to express sacrifice, vulnerability, and unconditional commitment. Locutionary acts play a role in constructing a literal narrative about protection and relationship inequality, while perlocutionary acts are aimed at evoking feelings of security and gratitude in the listener. Furthermore, the study of implicature reveals deeper implied meanings related to self-sacrifice, acceptance of inequality in relationships, and anticipatory commitment, which are often conveyed through the metaphors of “rain” and “war”. This study concludes that the power of lyrics lies not only in explicit romantic expressions, but also in the strategic use of language to perform actions and convey implicit values of devotion, reflecting the complex dynamics of human relationships, even when they are unbalanced. These findings emphasize the importance of pragmatic analysis in fully understanding the communicative and artistic impact of song lyrics.

This paper was made to explain the results of research on how to obtain the most appropriate citric acid adhesive composition in the manufacture of randu wood fiber composites in order to obtain a strong and suitable composite material. The research was carried out by experimental methods in the laboratory through a series of mechanical tests, namely the bending strength test and the screw grip strength test. The sample specimen is 5 cm × 20 cm × 1 cm for flexural strength testing and 5 cm × 10 cm × 1 cm for screw grip strength test. Composite specimens were made with variations in the composition of citric acid adhesives of 2.5%, 5%, 7.5%, 10%, 12.5%, 15%, 17.5%, and 20% by weight of randu wood. The results showed that the composite of randu wood particles with a citric acid matrix had optimal strength at a certain ratio, which was 7.5%. At the same ratio, the test results of the screw grip strength test also provide the highest value. These findings confirm that the exact composition of the adhesive has a significant impact on the final performance of the resulting composite.

This community service program was carried out to enhance the technological literacy of residents in Telang Sari Village through the introduction of an automated street lighting system based on sensor technology. The system presented to the community utilizes an Arduino microcontroller integrated with an LDR sensor to detect light intensity and an ultrasonic sensor to identify the presence of nearby objects. With this configuration, the street lights operate automatically: they turn on when the environment becomes dark and an object is detected, and turn off when the surroundings are bright or no activity is detected in the sensing area. The program activities included device installation, technical explanation, and a live demonstration to ensure that residents comprehended its functions and benefits. Additionally, the use of solar panels was introduced as an alternative power source to support sustainable operation without relying on grid electricity. The results of the program showed a positive response from the community, as the system was considered effective in improving nighttime safety, reducing energy consumption, and requiring minimal maintenance. Overall, this activity successfully increased public understanding of automation technology and renewable energy applications suitable for rural community development.

This community service program was carried out to enhance the technological literacy of residents in Telang Sari Village through the introduction of an automated street lighting system based on sensor technology. The system presented to the community utilizes an Arduino microcontroller integrated with an LDR sensor to detect light intensity and an ultrasonic sensor to identify the presence of nearby objects. With this configuration, the street lights operate automatically: they turn on when the environment becomes dark and an object is detected, and turn off when the surroundings are bright or no activity is detected in the sensing area. The program activities included device installation, technical explanation, and a live demonstration to ensure that residents comprehended its functions and benefits. Additionally, the use of solar panels was introduced as an alternative power source to support sustainable operation without relying on grid electricity. The results of the program showed a positive response from the community, as the system was considered effective in improving nighttime safety, reducing energy consumption, and requiring minimal maintenance. Overall, this activity successfully increased public understanding of automation technology and renewable energy applications suitable for rural community development.

This study explores the roles of innovation and perseverance as critical success factors for young entrepreneurs in the fried chicken business through an in-depth case study of Fried Chicken Smile, located in Medan Tembung Subdistrict. The research focuses on how young entrepreneurs are able to survive and grow in a highly competitive culinary market dominated by global brands such as KFC. Using a qualitative research approach, data were collected through in-depth interviews with business owners and employees, direct field observations, and documentation analysis. The study is supported by several theoretical perspectives, including Grit Theory, which emphasizes perseverance and passion for long-term goals; Entrepreneurial Behavior Theory, which explains proactive and adaptive business behavior; and Schumpeter’s Innovation Theory, which highlights innovation as a driver of competitive advantage. The findings indicate that business success is influenced by continuous product innovation, particularly through adapting menu flavors to local tastes, maintaining consistent operational quality, and implementing effective digital marketing strategies via social media platforms. In addition, strong social support from family, peers, and local communities plays a significant role in sustaining entrepreneurial motivation. Overall, the study demonstrates that the combination of innovation, persistence, and social capital enhances competitiveness and supports the growth of micro, small, and medium enterprises (MSMEs). These findings provide valuable insights for the development of young entrepreneurship in Indonesia’s dynamic culinary sector.

Unexpected downtime of a 2 kg/hour coffee grinder is crucial in cafe operations, thus less guaranteeing the availability of the grinder. The purpose of component replacement and repair planning is to obtain a prediction of the maintenance and repair schedule and costs in the 2026 period. The component replacement planning method includes collecting previous maintenance and repair data, applying the inspection-replace-repair-overhaul (IRRO) method, assessing component conditions, predicting component life, predicting technician costs, predicting supporting work equipment and supporting materials to be used in maintenance, predicting the time to replace spare parts or reinstall components after repair, estimating maintenance and repair costs for the 2026 period, and calculating the ratio of maintenance costs to profits. The results of component replacement and repair planning obtained maintenance costs for the 2026 period are IDR 2,350,000, - with an estimated coffee grinder rental rate of IDR 25,000/hour which has the potential to be rented for 1440 hours/year, and the ratio of maintenance costs to profits is 6.5% which implies that the coffee grinder with a capacity of 2 kg / hour is still suitable for use for the next few years and still has the opportunity to make a profit.

This community service activity was conducted at Grind Now Coffee Bar, an MSME in Batam City’s food and beverage sector, to address challenges in managing raw material inventory, which often led to inaccurate stock records, shortages, and overstocking, affecting daily operations and efficiency. The program aimed to improve inventory management by applying the Economic Order Quantity (EOQ) and Reorder Point (ROP) models, providing a systematic and measurable approach to procurement. Activities included detailed observation of operational practices, interviews with staff to understand current challenges, collection of data on raw material usage and purchasing patterns, and the implementation of a website-based inventory control system to streamline record-keeping and monitoring. The results showed that EOQ and ROP models helped determine optimal order quantities and appropriate reorder timing, while the inventory system improved organization, reduced errors, and enabled real-time stock monitoring. Overall, this intervention enhanced decision-making, promoted operational efficiency, and supported the sustainability and competitiveness of Grind Now Coffee Bar.

This study examines the influence of foreign ownership, return on assets (ROA), and firm size on environmental, social, and governance (ESG) disclosure among energy sector companies listed on the Indonesia Stock Exchange (IDX) during 2022–2024. The sample was selected through purposive sampling, including firms that consistently published annual and sustainability reports in accordance with the Global Reporting Initiative (GRI) standards. ESG disclosure was measured as the proportion of disclosed GRI indicators to the total applicable indicators. Multiple linear regression analysis shows that foreign ownership and firm size significantly enhance ESG disclosure, while ROA has no significant effect. These results support legitimacy theory, suggesting that companies increase ESG transparency primarily to secure societal acceptance and maintain their social license to operate. In the energy sector, where environmental sensitivity and public scrutiny are high, ownership structure and firm scale emerge as stronger determinants of ESG disclosure than short-term profitability.

This study aims to analyze the effect of Environmental, Social, and Governance (ESG) performance on financial misreporting, with investor attention as a moderating variable in banking companies listed on the Indonesia Stock Exchange during the 2019–2022 period. The theoretical framework is grounded in Agency Theory and Legitimacy Theory to explain the role of ESG as an internal control mechanism and a means of gaining external legitimacy. The research employs a quantitative approach using secondary data from annual reports and sustainability reports. Financial misreporting is proxied by earnings management measured through discretionary accruals, while ESG performance is assessed using the GRI Standards index, and investor attention is proxied by institutional ownership. Data analysis was conducted using multiple regression and Moderated Regression Analysis (MRA). The findings reveal that all three ESG dimensions (environmental, social, and governance) have a significant negative effect on earnings management. Institutional investor attention is found to strengthen the negative relationship between environmental and social aspects with earnings management, but weaken the influence of governance. These results indicate that institutional investors tend to be more responsive to environmental and social issues compared to governance aspects. Practically, this study provides empirical evidence that ESG implementation can serve as a control instrument against financial misreporting in the banking sector, while theoretically enriching the literature on investor moderation in the relationship between ESG and earnings management practices.

The dynamic changes in weather patterns in Jambi City require an accurate temperature prediction system, thus this study aims to compare the performance of Random Forest and Support Vector Regression (SVR) algorithms in predicting daily maximum temperatures using weather data from 2020–2024 obtained from OpenMeteo with the application of Feature Engineering including lag and rolling window features. The test results indicate that the SVR model with a Radial Basis Function (RBF) kernel optimized using Grid Search (C=10, epsilon=0.2, gamma=0.01) significantly outperforms Random Forest based on a statistical Paired T-test (p-value < 0.05), yielding an R-squared (R²) value of 87.46%, Mean Absolute Error (MAE) of 0.3818 °C, and Root Mean Squared Error (RMSE) of 0.4964 °C compared to Random Forest's R² of 84.05%, where the previous day's temperature (lag) and three-day rolling average were identified as the most dominant predictors, leading to the recommendation of SVR as the more effective method for temperature prediction in the study area.

Gestational Diabetes Mellitus (GDM) is a pregnancy-related metabolic disorder that poses health risks to both mother and fetus if not detected early, requiring accurate prediction methods for early screening and clinical decision-making. This study applies the Random Forest algorithm to detect GDM risk using clinical data from the Pima Indian Dataset. Data preprocessing included handling missing values, standardization, feature engineering, and a 70:30 train–test split. Two models were developed: a baseline and an optimized model using GridSearchCV hyperparameter tuning, validated with 5-fold cross-validation. Performance was assessed using a classification report, confusion matrix, and ROC–AUC. Results show that the optimized model outperforms the baseline, achieving 88% accuracy, an AUC of  93%, and average recall of 81%–85%. Compared to previous studies, this approach demonstrates improved predictive performance. The findings indicate that combining Random Forest with comprehensive preprocessing, feature engineering, and model optimization is effective and feasible for developing a medical decision support system for early GDM risk screening.

The concept of supremum is fundamental in real analysis and plays a crucial role in the optimization of single-variable real functions. In practice, not all functions attain their supremum explicitly, which necessitates numerical approaches to evaluate their behavior computationally. This study aims to analyze the supremum of several one-dimensional real functions with different characteristics using a grid-search method implemented in Python. Four functions were examined: a parabolic function, a rational function with a sharp peak, a discontinuous piecewise function, and a function with a vertical asymptote. The analysis involved modeling the functions, discretizing the domain, performing numerical approximation of the supremum, verifying the results against analytical values, and using graphical visualization to observe the function behavior near the supremum. The findings indicate that the supremum of the parabolic, rational, and piecewise functions can be accurately identified, with results consistent with analytical expectations despite minor deviations caused by grid resolution limitations in the rational function. Meanwhile, the function with a vertical asymptote yields an unbounded supremum, which cannot be attained within the domain. These results demonstrate that Python provides stable and reliable numerical estimates of the supremum across various types of one-dimensional real functions, validating the effectiveness of computational methods in supporting conceptual understanding of supremum.

This study aims to determine the optimal pectinase enzyme concentration and hydrolysis duration for the most preferred physical, chemical, and organoleptic characteristics of kweni mango syrup. The research was conducted from October 2024 to August 2025 at the Integrated Laboratory and Basic Science Laboratory of the Agricultural Institute (INTAN) Yogyakarta using a Completely Randomized Design (CRD) with a factorial pattern consisting of two factors and two replications. The first factor was the pectinase enzyme concentration (0%, 0.25%, 0.50%, and 0.75%), and the second factor was the hydrolysis duration (0, 30, and 60 minutes). Observation parameters included yield, vitamin C, viscosity, pH, total soluble solids, and organoleptic attributes. Data were analyzed using ANOVA at a 5% significance level followed by Duncan’s Multiple Range Test (DMRT). The results showed significant effects of both pectinase enzyme concentration and hydrolysis duration on yield, viscosity, total soluble solids, and organoleptic characteristics (color, taste, aroma, and overall acceptability), while no significant effects were observed on vitamin C content and pH. The best formulation was obtained using 0.50% pectinase enzyme concentration with a hydrolysis duration of 30 minutes.

This study examines the interrelationship between the implementation of administrative ethics in civil service, the professionalism of State Civil Apparatus (ASN), and the quality of public service delivery at the Provincial Department of Energy and Mineral Resources of Central Kalimantan, employing a qualitative case study approach. Through in-depth interviews, structured observations, and document analysis, the research finds that integrity, transparency, and ethical accountability function not merely as moral norms but as structural foundations that reinforce ASN professionalism in performing service functions, particularly within licensing processes that demand administrative certainty and responsiveness. Empirical findings indicate that professionalism—reflected in technical competence, procedural discipline, and ethical commitment—acts as a catalyst linking ethical values to effective and adaptive public service performance. Nevertheless, the study also identifies structural and cultural impediments, including regulatory inconsistencies, fragmented coordination, and limited training opportunities, all of which hinder the internalization of ethical principles and professional practice within the bureaucracy. Theoretically, the study posits that harmonizing administrative ethics and professionalism is a prerequisite for achieving key indicators of good governance, such as responsiveness, service effectiveness, and institutional accountability. Practically, the study recommends strengthening ethics training, enhancing ASN professional capacity, and advancing managerial reforms grounded in modern governance as strategic efforts to sustainably improve public service quality.

The global and national rates of cesarean section (CS) deliveries continue to show an increasing trend, including in Lampung Province. This study aims to analyze the factors associated with the increased incidence of CS deliveries at Griya Medika Dompet Dhuafa Hospital. An analytical quantitative design with a cross-sectional approach. The study population consisted of all mothers who gave birth during the period of January–June 2025. The sample was determined using the Slovin formula, yielding 240 medical records selected through simple random sampling. The independent variables included maternal age, educational background, obstetric history, and medical indications, while the dependent variable was CS delivery. The study was conducted from July to August 2025. Data were analyzed using univariate and bivariate methods with the Chi-Square test. The results showed that most respondents underwent CS delivery (95%). Maternal characteristics included non-risk age (73.8%), secondary education (38.3%), multiparity (54.2%), and the most common medical indication was fetal indication (55.4%). Bivariate analysis indicated no significant relationship between maternal age (p=0.519), educational background (p=0.509), and obstetric history (p=0.694) with CS delivery. Conversely, there was a significant association between medical indications and CS delivery (p=0.041). It was concluded that the increasing rate of CS deliveries is predominantly influenced by medical indications, particularly fetal indications. Therefore, it is recommended that health workers enhance early detection of pregnancy and childbirth risks and strengthen educational efforts for pregnant women as preventive measures to reduce the incidence of CS

Organic waste management at Yogyakarta International Airport (YIA) is still not optimal, even though organic waste production averages 1,264 kg per month. This community service activity aims to develop technological innovations through the utilization of eggshell waste and Black Soldier Fly (BSF) maggots into economically valuable pellet feed products. The activity was carried out from October 8 to 15, 2025, involving three workers from the Temporary Processing Site (TPS) of PT Angkasa Pura Indonesia YIA. The implementation methods included an initial survey, education, demonstration of pellet production, and evaluation of participants' skills and product quality. The production process involved drying, grinding the ingredients, mixing the ingredients, molding, and drying the pellets. The results showed that the workers were able to independently carry out the production process and produce pellets with good physical quality. Cost analysis showed that the cost of production was IDR 47,989/kg, with a potential profit margin of 30% and an estimated return on investment within ±7 months. This innovation has proven effective in reducing waste volume, increasing the added value of organic waste, and supporting the principles of zero waste and circular economy in the airport area. This program has the potential to be further developed as a model for sustainable organic waste management.

This study aims to describe the use of the innovative Periscope Grid media based on hybrid learning in two-dimensional drawing lessons for elementary students. The media was designed to help students understand perspective and proportion concepts by combining a manual transparent grid frame with digital features accessed through QR codes linked to tutorial videos, artwork galleries, and reflective learning materials. The research employed a descriptive qualitative approach involving fourth-grade elementary students. Data were collected through classroom observations, interviews with teachers and students, and documentation of students’ artwork. The data were analyzed interactively using reduction, presentation, and conclusion drawing stages. The findings reveal that the Periscope Grid effectively enhances students’ ability to observe, replicate, and draw proportional two-dimensional objects while promoting collaboration through digital gallery activities. Moreover, the media helps teachers explain perspective concepts more easily and fosters students’ active participation. It can be concluded that Periscope Grid serves as an effective, engaging, and integrative learning medium suitable for 21st-century visual art education in elementary schools.

Problems in the meatball dough grinder are low production, increasing maintenance costs and disappointed meatball dough customers who receive orders late due to problems with the electric motor, Pulley, V belt, cutting knife. The purpose of the replacement scheduling is to obtain costs, maintenance-repair schedules in the period 2026, and the ratio of maintenance costs to profits. The replacement scheduling method includes collecting previous period maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component working conditions, predicting component life, predicting repairman costs, predicting supporting equipment that will be used in maintenance, predicting the time to replace spare parts or reinstall components after repair, estimating maintenance and repair costs in 2026, and calculating the ratio of maintenance costs to profits. The results of the replacement scheduling show that the maintenance costs in 2026 are IDR 2,530,000 with an estimated rental rate for the meatball dough grinder of IDR 10,000/kg which has the potential to be rented for 1300 hours/year, and the ratio of maintenance costs to profits is 4.9% which implies that the meatball dough grinder with a capacity of 5 kg/hour still has the potential to sell well and is suitable for use in the coming years.