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The increasing demand for electricity and high dependence on the utility power grid have driven the adoption of photovoltaic (PV) power generation as an environmentally friendly alternative energy source. This study aims to analyze the techno-economic feasibility of a load-sharing PV power generation system, focusing on technical analysis, operational costs, electricity bill savings, and environmental impacts. The research was conducted using quantitative methods to compare energy from photovoltaic generation and the grid, carbon emission calculations using an emission factor of 0,87 kgCO₂/kWh, and economic evaluation through parameters such as Net Present Value (NPV), Return on Investment (ROI), Cost of Energy (COE), and Payback Period (PP). The research results indicate that the photovoltaic panel generation system enables reducing utility grid energy consumption and reducing carbon emissions by 4,85 tons of CO₂ in 2024, increasing to 8,45 tons of CO₂ in 2025. The economic analysis indicates that the NPV value is not yet optimal; however, the ROI stands at 15%, the COE is Rp. 980.08/kWh, and the Payback Period is 6,56 years. The system is feasible for long-term investment. Overall, the implementation of the photovoltaic power plant demonstrates good potential in supporting carbon emission reduction, increasing the utilization of renewable energy, and reducing dependence on fossil-based energy.

This article explores the integration of epigenetics and Christian restoration theology as a new framework for understanding trauma and human restoration holistically. Epigenetics demonstrates that life experiences, particularly trauma, can influence gene expression without altering DNA structure and may even be transmitted across generations. Meanwhile, Christian restoration theology emphasizes the grace of God as a power that restores humanity completely in spiritual, psychological, relational, and embodied dimensions. This study employs a qualitative library research approach by examining recent scientific and theological literature relevant to trauma, epigenetic change, restoration, and Christian understandings of grace. The findings reveal that trauma leaves measurable biological imprints within the body, yet epigenetic changes remain reversible through healthy relationships, therapeutic interventions, and spiritual practices. These results indicate that human restoration should not be viewed only as an inward spiritual experience, but also as a holistic process involving psychological healing and biological renewal. Therefore, grace can be understood as a transformative power that works comprehensively within the spiritual, psychological, and biological dimensions of human existence, opening possibilities for intergenerational healing and renewed life for contemporary theological reflection.

This study aims to examine the influence of price and electronic word of mouth (e-WOM) on purchase decisions among Generation Z consumers in Campaka Subdistrict, Bandung City, with a specific focus on the TikTok Shop platform. This research employs a quantitative approach using a survey method by distributing questionnaires to Generation Z consumers in Campaka Subdistrict, Bandung City, with a total of 98 respondents to collect the data. The results of the study indicate that both price and electronic word of mouth have a significant positive effect on purchase decisions among Generation Z consumers in Campaka Subdistrict, Bandung City. Price is generally perceived as good, although aspects related to price suitability based on income levels and purchasing power still show some weaknesses. Similarly, e-WOM activity is considered positive; however, there are still relatively weak aspects regarding the diversity of consumer reviews, as not all respondents actively pay attention to the variation of opinions in reviews. The findings also reveal a significant influence of these variables, where the effect of price on purchase decisions reaches 35.4%, while electronic word of mouth contributes 29.5%, and the combined effect of price and electronic word of mouth on purchase decisions is 64.9%. This study concludes that improvements in price perception and e-WOM can enhance purchase decisions.

Modern urban churches, specifically Gereja Bethel Indonesia (GBI) PRJ Jakarta, face challenges in bridging the intergenerational gap in leadership regeneration. This research aims to reformulate the paradigm of church leadership towards the next generation by exploring the theological meaning of Jesus' act of washing His disciples' feet based on the text of John 13:12-17. Using a qualitative method through a library research approach as well as textual and contextual biblical analysis, this study deconstructs the concept of worldly elitist power into a servant leadership model. The results of the expository analysis show that Jesus validated His historical and political authority not through social status distance, but through incarnational ministry, relational proximity, and role modeling. As a practical implication for the quality of ministry at GBI PRJ Jakarta, these findings recommend a strategic transition from a one-way communication leadership style to relational mentoring, the empowerment of the younger generation through the delegation of authority, and the tangible modeling of integrity. In conclusion, the improvement of shared ministry quality highly depends on the willingness of church leaders to lay aside structural egos and disciple the younger generation through the example of humility centered on the work of the cross of Christ.

Generators are one of the important auxiliary aircraft needed on ships for power generation. During the operation of a diesel generator, continuous rotation occurs resulting in friction and erosion of the moving parts. The supporting factor for the smooth running of a diesel engine is a lubrication system that is supported by good lubricating oil quality, besides that it also needs to be supported by an adequate and good cooling system. The use of lubricants is one of the most important factors to ensure the performance of diesel engines. The lubricant is in charge of maintaining the condition of the engine so that it remains stable. This study aims to analyze the effect of using lubricating oil beyond the operating hours limit on engine heat. Furthermore, it also discusses steps to ensure diesel engine temperatures remain normal. This research was carried out during the practice of sailing on a ship for approximately one year. This study uses a descriptive quantitative research method. The primary data obtained directly utilizes observation methods, and documentation. Secondary data was obtained from existing articles and journals. The data analysis techniques used are descriptive analysis and inferential analysis. The results of this study show that the working hours of lubricating oil use have a significant influence on the increase in the temperature of diesel generator engines as evidenced by hypothesis tests on two engine units, namely AE1 and AE2. In the AE1 unit, a t-value of 18.467 with a significance of 0.000 was obtained, while in AE2 the t-value was 14.289 with a significance of 0.000. The significance value in both units is less than 0.05 so it can be concluded that the working hours of lubricated oil have a significant influence on the temperature of the genarato diesel engine on the ship.

This research aims to design and develop a prototype wave power plant that utilizes the vertical motion of a buoy as a source of mechanical energy, which is then converted into electrical energy using a recoil starter mechanism. The system is designed to be installed at the stern of a prototype ship. The vertical movement of the buoy caused by ocean waves is transmitted to the recoil starter through a drive rope, producing a stable one-way rotational motion. This rotation is further transmitted to a gearbox to increase rotational speed before driving a DC generator. The electrical energy generated is stored in a 12 VDC battery, supported by a buck–booster converter to stabilize the output voltage. This study employs an experimental engineering approach to evaluate system performance based on empirical test data. The main components of the system include a buoy as a wave energy collector, a recoil starter as the initial rotating mechanism, a DC generator as the electrical energy producer, a buck–booster converter as a voltage regulator, a 12 VDC battery as an energy storage unit, and a monitoring system based on an ESP32 microcontroller integrated with a PZEM-017 sensor. Experimental results show that the recoil starter operates effectively in driving the generator under both no- load and buoy-loaded conditions. Increases in generator rotational speed are directly proportional to increases in output voltage and current. The PZEM-017 sensor demonstrates a high level of measurement accuracy, approaching 100% when compared with a multimeter. Overall, the proposed wave power generation system functions reliably and shows potential for further development as a small-scale alternative renewable energy source.

The increasing demand for electrical energy and the limited availability of fossil fuels have driven the development of renewable energy sources, including marine current energy, which remains underutilized in coastal and remote maritime regions. This study presents the design and realization of a small-scale marine current power generation prototype using a horizontal axis propeller turbine with a NACA S814 blade profile and analyzes the effect of turbine rotational speed on electrical power output. The system converts marine current kinetic energy into mechanical energy through turbine rotation and subsequently into DC electrical energy using a generator, which is stabilized by a Buck–Boost Converter and Maximum Power Point Tracking (MPPT) for charging a 12 VDC battery. Real-time monitoring of electrical and mechanical parameters is implemented using an Internet of Things (IoT)–based system comprising an ESP32 microcontroller, a PZEM-017 sensor, and an RPM sensor. Experimental results demonstrate a positive correlation between water flow rate, turbine rotational speed, and generator output voltage. The system begins operating at a minimum flow rate of 35.2 L/s at 56 RPM, producing 0.2 V, while optimal performance is achieved at 45.3 L/s and 516 RPM, generating up to 13.3 V. These results indicate that the proposed prototype is a viable alternative renewable energy source for marine applications.

The shaft is a crucial component in mechanical systems because it serves to transfer power and rotational motion throughout the machine. This research aims to assess the structural strength and operational performance of shafts used in a tire shredding machine through numerical simulation methods in order to achieve a safe and efficient design. The study involved several stages, including the development of shaft geometry models, the determination of boundary conditions, load application, mesh generation, and stress analysis using the finite element method. Two shaft configurations were examined: a 59 mm diameter shaft made from AISI 1045 steel and a 49 mm diameter shaft manufactured from ASTM A36 steel. The simulation results indicate that the 59 mm shaft experiences a Von Mises stress of 8.9 × 10⁻⁵ MPa, with a maximum displacement of 0 mm and a safety factor of 15. Similarly, the 49 mm shaft shows a Von Mises stress of 8.4 × 10⁻⁵ MPa, no measurable displacement, and a safety factor of 15. These findings confirm that both shaft designs are capable of safely withstanding the applied working loads. In addition, cutting system tests revealed that a 24-tooth blade achieved an efficiency of 26.9%, while a 40-tooth blade reached only 22.3%, indicating that the 24-tooth configuration provides better performance.

Land conflict between the Sihaporas indigenous community and PT Toba Pulp Lestari (TPL) remains an ongoing agrarian issue that directly affects the community’s livelihoods. The inclusion of the company’s concession within the customary territory has changed patterns of land control and use that were previously managed collectively across generations. This situation restricts access to agricultural land and forests, reduces sources of income, and creates social tensions and confrontations. This study aims to analyze the impacts of land conflict on the Sihaporas indigenous community and to examine the conflict through a political ecology perspective with a focus on power relations among actors. Using a qualitative case study approach, data were collected through interviews, observations, and document analysis. The findings show that the conflict affects economic, social, and cultural aspects of the community and reflects unequal power relations between indigenous peoples, corporations, and the state in controlling agrarian resources.

Increasing operational efficiency in power generation systems is crucial in overcoming the increasing energy demand, especially in the industrial sector. One solution to improve the efficiency is to optimize the use of economizer in the boiler of Steam Power Plant (PLTU). This study analyzes the impact of using an economizer in a 240 ton/hour capacity CFB boiler at PT X on system efficiency and fuel consumption. The results of the analysis show that the use of an economizer can increase the average feed water temperature from 207.73°C to 298.96°C, with a temprature increase of 91.23°C. This temperature increase reflects the economizer's ability to utilize flue gas heat to heat the feed water, which has an impact on reducing fuel consumption by 17.18%, from 45716.56 kg/hour to 37862.50 kg/hour. The boiler efficiency also increased significantly, from 68.36% to 82.54%, which shows the positive impact of the economizer on boiler performance. This study concludes that the use of economizer can improve energy efficiency and reduce fuel consumption, and is recommended to be applied to large capacity boiler systems to optimize energy savings and operational efficiency. Further research is needed to explore the influence of other variables on economizer and boiler performance in more depth.

Steam turbines remain a core technology in thermal power generation and continue to evolve through advances in aerothermal design, materials, control strategies, and digital maintenance. This paper presents a systematic literature review (SLR) of recent international studies published between 2020 and 2025 to synthesize current developments in steam turbine performance and thermal efficiency improvement. Article identification was conducted through SCOPUS using keywords related to turbine efficiency, blade/nozzle optimization, failure analysis, and material enhancement. The selected studies were analyzed thematically across four domains: (1) design and optimization using CFD/FEA, (2) material and structural resilience, (3) operational performance under variable/part-load conditions, and (4) integration with hybrid renewable systems and predictive maintenance. The reviewed evidence indicates that CFD-based nozzle/blade optimization and advanced control approaches can yield measurable efficiency improvements (approximately 2–7.3%), while material innovations and enhanced cooling strategies improve durability by mitigating thermal stress and fatigue risks. In parallel, digitalization through IoT-based predictive maintenance and additive manufacturing is increasingly reported as a pathway to reduce downtime and accelerate component production. However, recurring gaps include limited real-world validation, insufficient studies in humid/tropical environments, and a lack of long-term economic/lifecycle assessments. Future work should prioritize experimental or field verification, region-specific performance studies, and integrated techno-economic evaluation to support broader deployment of high-efficiency steam turbine systems.

Language barriers represent one of the most significant obstacles to educational equity and access worldwide. This study investigates the application of Natural Language Processing (NLP) technologies in multilingual educational contexts to facilitate cross-linguistic learning and improve educational outcomes for linguistically diverse student populations. We implemented and evaluated a comprehensive NLP-powered multilingual learning platform across 47 educational institutions in 12 countries, serving 8,450 students speaking 23 different languages. Our experimental framework integrated machine translation, speech recognition, multilingual content generation, and adaptive language learning algorithms. Results demonstrate that NLP-enhanced multilingual education improved student comprehension by 43.6% (p<0.001), increased participation rates by 67.8%, and reduced achievement gaps between native and non-native speakers by 52.4%. Students using NLP-assisted learning tools achieved test scores averaging 78.3% compared to 54.7% for control groups. However, challenges persist regarding cultural context preservation, idiomatic expression handling, and equitable performance across language families. This research provides evidence that NLP technologies can effectively democratize education across linguistic boundaries while identifying critical areas requiring continued development.

This research was conducted at PT PLN Nusantara Power UP Paiton, one of the largest coal-fired power plants (PLTU) in Indonesia, which focuses on reducing the generation of hazardous and toxic oil waste through the implementation of an oil purification system. The use of large amounts of lubricating oil in the Electro-Hydraulic System (EHS) has the potential to produce high amounts of used oil waste. To address this, the company implemented two main technologies, namely Water Content and Varnish Removal, which function to reduce water content and varnish layers so that the oil can be reused without reducing engine performance. This research used a quantitative descriptive method with data collection techniques through field observations, interviews, and operational documentation from 2021 to 2024. The results showed that the oil purification system was able to reduce hazardous and toxic waste generation by 11.46 tons over four years. In addition to providing environmental benefits, the implementation of this system also resulted in savings in oil waste costs of approximately Rp6,200,560,000. Technically, purification maintains engine performance by reducing water and varnish content, while from an environmental perspective, this activity supports the principle of reduce in hazardous and toxic waste management. Overall, the oil purification system has proven effective in improving operational efficiency, extending oil life, and supporting sustainable waste management for industrial operations.

Corrective maintenance is one of the maintenance strategies performed after system failures or malfunctions occur, particularly in diesel power plants (PLTD) that play a crucial role in supplying electricity to remote areas such as Jayapura. This study aims to identify the types of failures occurring in diesel engines at the Jayapura PLTD and to evaluate the corrective maintenance actions implemented. Data were collected through direct observation during an internship program, interviews with technicians, and analysis of historical maintenance and failure records. The results indicate that the most common failures occurred in the lubrication system, fuel system, and cooling system. Corrective actions included component repairs, spare part replacements, and system adjustments. The application of timely and appropriate corrective maintenance significantly reduced machine downtime and improved the reliability of the power generation system. This study recommends integrating corrective and preventive maintenance strategies to maximize operational efficiency of the PLTD.

This study explores how the organizational culture of Sanggar Kartika Budaya strengthens local artistic values through identity building, leadership, training strategies, and adaptive creativity. Rooted in a commitment to traditional arts, the sanggar positions local cultural expression not only as heritage but also as a living space for innovation. The research aims to uncover how these cultural elements shape member behavior, sustain artistic traditions, and support the regeneration of young artists. Using a qualitative approach with document analysis, this study examines official profiles, program descriptions, and relevant scholarly sources. The findings reveal that the sanggar’s cultural identity centered on the motto “Pegang Teguh Seni Tradisi Siap Berkreasi”serves as the backbone of its learning system and creative ecosystem. Leadership plays a central role in directing artistic vision while safeguarding cultural authenticity. Structured training, literacy activities, and collaborative performances effectively embed traditional values in new members. The sanggar also demonstrates an ability to evolve with modern trends through creative choreography, multimedia integration, and active participation in contemporary festivals, all while maintaining strong roots in local heritage. These findings highlight how a well-structured organizational culture can act as a powerful engine for cultural preservation and artistic resilience. The implications suggest that cultural institutions can remain relevant in a fast-changing era by blending heritage with innovation, ensuring that tradition continues to live meaningfully in the hands of future generations.

The crankshaft is a vital component of an engine that converts the linear motion of the piston into rotational motion to produce mechanical power for electricity generation. This study employs a descriptive qualitative method, utilizing data collection techniques such as observation, interviews, and literature review. The objective of this research is to analyze the factors contributing to the occurrence of cracks in the crankshaft of a diesel engine used as a generator prime mover. The findings indicate that the cracks are primarily caused by contamination of the lubricating oil with water, resulting from leakage in the lubricating oil cooler or tube oil cooler. Another contributing factor is the loosening of the connecting rod bolts, which may occur if they are not tightened to the specified torque or if a torque wrench is not used during installation. Corrective measures undertaken include replacing the gasket, repairing or replacing the leaking tube oil cooler, and retightening the connecting rod bolts using a torque wrench in accordance with the manufacturer’s specifications.

The growing demand for energy-efficient and intelligent thermal systems has driven significant advancements in adaptive compressor design. This paper presents a comprehensive literature review on the development of AI-based compressor systems, with a specific focus on enhancing efficiency under partial-load conditions and optimizing the utilization of residual energy. Through the synthesis of five recent high-impact studies (2020–2025), we examine the application of deep reinforcement learning (DRL), hybrid evolutionary algorithms, and neural network surrogate modeling in compressor optimization. Key findings indicate that model-based DRL combined with surrogate CFD can achieve up to 8% efficiency gains at off-design conditions. Hybrid approaches integrating Genetic Algorithms (GA) with DRL reduce optimization time by 30% while improving pressure ratios. Neural network surrogates provide high-speed, real-time performance predictions with less than 1% error, enabling mass iterative design. Furthermore, intelligent load classification using radial basis function networks (RBFN) allows adaptive response to varying operating conditions with over 95% accuracy. Collectively, these methods form a framework for intelligent, self-optimizing compressor systems capable of real-time adaptation and energy recovery. The results suggest that AI-enhanced adaptive compressors represent a transformative direction for energy-sensitive sectors, including HVAC, power generation, and sustainable industry.

This study aims to analyze the quality of coal from the AR_10 borehole in Muara Enim Regency, South Sumatra, based on proximate analysis. The AR_10 borehole has three coal seams (A, B, and C) that were analyzed using the standard ASTM method to determine the coal quality characteristics. The parameters analyzed include total moisture (TM), volatile matter (VM), fixed carbon (FC), ash content (Ash), calorific value (CV), and total sulfur (TS) on an as-received (AR) basis. The analysis results show that seam A has the highest moisture content (19%), seam B exhibits the optimal calorific value (6045 kcal/kg), and seam C has the highest fixed carbon content (42.63%) with the highest sulfur content (0.83%). The correlation between parameters indicates that increases in moisture and ash content negatively affect the calorific value, while an increase in fixed carbon is positively correlated with the calorific value. All three seams fall into the category of low to medium rank coal (subbituminous to high volatile bituminous) with adequate quality for power generation and industrial purposes. This research provides an important contribution to the characterization of Muara Enim Formation coal in South Sumatra for the optimization of local coal resource utilization.

State speeches in international forums are a strategic arena for the practice of diplomacy and leadership image management. This study analyzes President Prabowo Subianto's rhetorical style in his speech at the 80th UN General Assembly on September 23, 2025. Using Aristotelian theory, namely ethos, pathos, and logos, to understand how rhetoric functions in strengthening political legitimacy, humanitarian solidarity, and international policy arguments. Using a qualitative-descriptive approach, this study examines transcripts of official speeches and identifies quotations that represent each persuasive mode. The analysis shows that Prabowo builds ethos through historical references, concrete actions of Indonesia such as the contribution of peacekeeping troops, and pathos is depicted through narratives of suffering, calls for solidarity, and an emphasis on the future of the younger generation; while logos is demonstrated through the presentation of data, policy plans such as the net-zero target, technical solutions such as sea walls, and systematic cause-and-effect arguments. This combination of ethos, pathos, and logos confirms that the speech was not simply a policy statement but also a rhetorical diplomatic tool that strengthened Indonesia's image as a constructive global actor. These findings contribute to the study of leadership communication and diplomatic rhetoric, particularly in the context of developing countries seeking to enhance the role of multilateralism and soft power.

Indonesia's dependence on fossil energy, which reaches 98%, results in high CO₂ emissions and energy costs. This study aims to design a wind energy system to meet electricity needs at the Arafuru Field of the Indonesian Navy Academy (AAL), which is strategically located near the coast with adequate wind potential. A quantitative research method was used by collecting wind speed data for three months (January-March 2025) at coordinates 7.21755° S, 112.71022° E. The data shows an average wind speed of 2.32 m/s with unpredictable direction. Based on the analysis, the SH-X 10000 vertical wind turbine was selected as the most suitable solution. Calculation results show that one turbine unit can generate power of 104,999 watts, so to meet the total power requirement of 109,120 watts, at least 2 wind turbine units are needed. This system not only reduces dependence on PLN and fossil energy but also has the potential to reduce CO₂ emissions and can be utilized as a learning laboratory for AAL cadets. The implementation of wind energy at AAL's Arafuru Field is expected to be a concrete step in the transition towards renewable energy in the military environment.