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International trade plays a vital role in strengthening Indonesia’s economic growth, particularly through the export of fishery products which are among the country’s leading commodities. Fresh fish exports are highly influenced by external demand factors in destination countries as well as Indonesia’s own production capacity. This study aims to analyze the determinants affecting Indonesia’s fresh fish exports to its main trading partners, namely China, Japan, Hong Kong, Singapore, and Malaysia, over the period 2012–2023. The research utilizes secondary data sourced from the World Bank and the Central Statistics Agency (BPS). Several independent variables are considered, including the fish production levels in the importing country, the real gross domestic product (GDP) per capita of the importing country, and the total population of the importing country. Panel data analysis was employed to capture the variations across time and countries, with the Random Effect Model (REM) chosen based on the results of the model specification tests. The findings of the analysis indicate that fish production in the importing country exerts a negative and statistically significant effect on Indonesia’s fresh fish exports, suggesting that higher domestic fish production in these countries reduces the need for imports. Conversely, the real GDP per capita of the importing country and its population size were found to have positive and significant impacts on Indonesia’s export volumes. These results highlight that wealthier and more populous nations demonstrate stronger demand for imported fresh fish, including from Indonesia. The implications of this study underscore the importance for Indonesia to continuously improve the quality, safety, and competitiveness of its fresh fish products while also adopting effective marketing and trade strategies targeting countries with high purchasing power and large consumer bases.

Asynchronous motors, commonly known as induction motors, are widely utilized due to their robustness, reliability, and efficiency in both industrial and household applications. These motors typically operate by converting electrical energy into mechanical energy through the interaction between a rotating magnetic field and the rotor. Under normal operating conditions, the rotor speed is always slightly less than the speed of the magnetic field, which is known as "slip." However, when the slip becomes negative, meaning that the rotor speed exceeds the speed of the rotating magnetic field, the motor begins to function as a generator. This condition occurs when the motor is driven above its synchronous speed by an external mechanical force, causing the rotor to generate electrical power. Using an asynchronous motor as a generator offers several notable advantages. One of the key benefits is its ability to produce a pure sine wave voltage, which is crucial for various applications that require stable and high-quality electrical power. Since these motors do not use brushes, they are free from the problems associated with brush wear and maintenance. Moreover, they do not generate radio frequency interference (RFI), making them suitable for environments sensitive to electromagnetic disturbances. The use of an asynchronous motor as a generator also provides the ability to function as a rotary phase converter. This is especially beneficial in applications where three-phase power is unavailable, but the load requires it. To facilitate this process, a capacitive voltage is required to induce excitation in the rotor. The capacitive current is supplied by an additional capacitor, which is installed in parallel with the motor output. This capacitor helps maintain the necessary phase shift and enables the motor to generate the required three-phase power.

This research examines the vital role of pesantren education in embedding and sustaining moral values within the broader social context, with a particular focus on Pondok Pesantren Raudlatul Muta’allimin Kudus. As traditional Islamic institutions, pesantren not only function as centers for religious instruction but also act as moral guardians that shape the character, ethics, and social behavior of students and their surrounding communities. In the midst of rapid globalization and shifting cultural dynamics, pesantren face the challenge of preserving the relevance of Islamic values while adapting to contemporary realities. The purpose of this study is to investigate how pesantren education contributes to moral development and to identify strategies utilized to instill Islamic ethics. Using a qualitative case study approach, the research gathered data through interviews, direct observation, and documentation involving kyai, teachers, students, and community members. The findings show that pesantren foster moral growth through structured daily rituals, integration of moral teachings in curriculum, exemplary leadership (uswah), and active community-based programs. These practices build discipline, honesty, empathy, and social responsibility in students, which in turn positively affect the surrounding society. Furthermore, the leadership model demonstrated by kyai and teachers plays a central role in reinforcing values through example, rather than instruction alone. The study concludes that pesantren education continues to serve as a powerful moral force by blending religious instruction with practical community engagement, ensuring that values are not only taught but also lived. This underscores the relevance of pesantren as adaptive agents of moral transformation capable of addressing the ethical challenges of modern Muslim societies. It also highlights that the pesantren framework can serve as a replicable model for strengthening character education in diverse social and cultural contexts, making it both traditional and forward-looking.

The contractual relationship between government entities (PA/KPA/PPK) and construction service providers in procurement activities is complex, as it intersects with both public and private law. Government procurement contracts for construction projects are often structured through a tender process, where service providers must compete to win the contract. Once the provider is selected, a legal agreement is formed, which regulates the roles, responsibilities, and obligations of the parties involved. This agreement is typically outlined in a contract document that serves as a formal, legally binding commitment. In civil law, such contracts are typically governed by private law principles, which include contracts, obligations, and liabilities. However, the nature of government procurement contracts adds a unique element of public law, particularly administrative and criminal law. The government’s involvement in these contracts introduces a dual legal framework that governs the relationship between the parties. On one hand, the contract is influenced by the state’s regulatory powers and administrative authority, ensuring compliance with legal standards and public interests. On the other hand, it is also subject to private law principles, as the government enters into agreements with construction providers just like any other business transaction. This mixed legal framework (or "mixed law") creates a distinctive legal relationship, where elements of public law, such as administrative regulations and oversight, coexist with private law principles, such as those governing contract enforcement and dispute resolution. The contract, which is a Keputusan Tindakan Administrasi Negara (KTUN), remains a civil law act, despite its public law foundation. This hybrid nature of government contracts ensures that both public and private law aspects are considered in the process, which can sometimes lead to legal complexities and challenges in the implementation and enforcement of these contracts.

This study focuses on the symbolic meanings embedded in the use of figurative language in the poetry anthology Selamat Menunaikan Ibadah Puisi by Joko Pinurbo. The research utilizes a descriptive qualitative approach, with semiotic analysis serving as the theoretical foundation. The purpose of this study is to examine how the figurative language used in the poems contributes to conveying deeper symbolic meanings, beyond their role as mere rhetorical devices. The findings of this research reveal that the figurative language within the poems plays a significant symbolic role in expressing complex themes such as inner suffering, memories, identity, alienation, and the quest for the meaning of life. Symbols like 'storm,' 'refrigerator,' 'dusk,' 'window,' 'door,' 'river,' and others are employed to represent abstract concepts, providing a more nuanced understanding of the human experience. The study identifies various types of figurative language, including metaphor, simile, personification, hyperbole, synecdoche, paradox, and irony. Each of these elements serves to enrich the meaning of the poems, adding layers of depth to the interpretation and enhancing the aesthetic experience for the reader. Through these figurative expressions, the poet effectively invites the reader to engage with both the emotional and intellectual dimensions of the poetry. This research emphasizes how Joko Pinurbo's use of figurative language transcends its traditional ornamental function, making it a powerful tool for conveying complex symbolic and existential themes. By analyzing the symbolic meanings in the poems, this study contributes to a deeper appreciation of the interplay between language, meaning, and emotion in contemporary Indonesian poetry.

This study aims to examine and analyze the Islamic educational values ​​contained in the local tradition of Ada' Tuho Ulumanda and its implementation at the Darul Ulum Islamic Boarding School, Popenga Village, Ulumanda District, Majene Regency. The Ada' Tuho tradition is one of the cultural heritages of the Ulumanda community that is full of moral, social, and spiritual values ​​that are closely related to the principles of Islamic education, especially the values ​​of faith, morals, and society. In the context of Muslim society, local traditions are not only seen as cultural symbols, but also function as a medium for transmitting religious values ​​that strengthen Islamic identity while maintaining social harmony. The research method used is a descriptive qualitative approach with data collection techniques through observation, in-depth interviews, and documentation. The data obtained are analyzed thematically to reveal the Islamic educational values ​​contained in the practice of Ada' Tuho and its form of implementation in the Islamic boarding school environment. The results of the study indicate that the Ada' Tuho tradition contains a number of important values, including: the value of monotheism that emphasizes faith and respect for God's power, moral values ​​that include honesty, responsibility, discipline, and respect for parents and others, and social values ​​in the form of solidarity, mutual cooperation, deliberation, and justice in community life. The implementation of these values ​​at the Darul Ulum Islamic Boarding School is carried out through a formal learning process, habituation of worship, exemplary behavior of the ustaz, and strengthening the character of students based on the integration of Islamic values ​​and local wisdom. Thus, the Islamic boarding school plays a role as an agent of preserving religious culture that is able to harmonize Islamic teachings with local traditions constructively, making it relevant to strengthening contextual Islamic education in the modern era.

Athletic physical condition is a key factor in determining an athlete's performance during competitions. This study aims to assess the physical condition of Unesa Women FC athletes using a descriptive quantitative method, involving 20 athletes as the sample. Data was collected through a series of physical tests to measure various aspects of physical fitness, including aerobic endurance, speed, agility, leg strength, and explosive power. The tests conducted included the Multistage Fitness Test (MFT) for aerobic endurance, a 30-meter sprint for speed, Illinois Agility Run for agility, Leg Dynamometer for leg strength, and Jump MD for explosive power. The results of the study show that the average VO2Max of the athletes is 30.8 ml/kg/min, which falls into the "Poor" category. This indicates that the athletes' aerobic endurance has not yet reached the optimal standard required for competitive performance. The 30-meter sprint time recorded was 5.53 seconds, categorized as "Good," indicating that the athletes have adequate speed. However, the agility score obtained from the Illinois Agility Run was 21.97 seconds, classified as "Poor," suggesting that the athletes need to improve their agility for quicker movements on the field. The explosive power score, measured by the Jump MD test, was 45.75 cm, which also falls into the "Poor" category, while leg strength, measured using the Leg Dynamometer, resulted in a score of 57.47 kg, classified as "Very Poor." These findings indicate that most components of the physical condition of the Unesa Women FC athletes are still below optimal levels. Therefore, the study emphasizes the need for a more structured and targeted physical training program tailored to the individual needs of each athlete. A training program designed based on these test results will help improve the physical fitness components that are lacking and support the enhancement of their performance during competitions.

A fiduciary guarantee agreement is a formal agreement that must be stated in a notarial deed as regulated in Article 4 of the Fiduciary Guarantee Law. This provision states that a fiduciary guarantee is a subsidiary agreement of the main agreement that creates an obligation for the parties to fulfill a performance. Execution, in this context, is a legal action carried out based on a legally binding decision. Article 15 paragraph (2) of the Fiduciary Law explains that the executorial power of a fiduciary guarantee certificate allows for direct implementation without going through a court, is final, and binds the parties. This research uses an empirical normative method, namely combining library studies with field research. Primary data was obtained through interviews with Judges of the Yogyakarta District Court, Judges of the Sleman District Court, the Yogyakarta State Assets and Auction Service Office (KPKNL), and the Yogyakarta Regional Office of the Ministry of Law and Human Rights. Secondary data comes from primary, secondary, and tertiary legal materials. The analysis was conducted qualitatively. The research results indicate that following Constitutional Court Decision No. 18/PUU-XVII/2019, the execution of fiduciary collateral objects can no longer be carried out unilaterally by creditors, but must instead be filed through the District Court. This provision balances the legal standing between debtors and creditors and prevents potential arbitrariness. Nevertheless, execution through the courts is an alternative if there is no agreement between the parties regarding a default. The court's role following the Constitutional Court decision includes resolving disputes between creditors and debtors and ensuring that execution procedures are carried out in accordance with the HIR (Regional Regulations for the Protection of Creditors), RBG (Regional Regulations for the Protection of Creditors), and the Supreme Court's technical instructions. In general, the execution mechanism through the courts is considered quite effective in ensuring legal protection for both parties.

Clean and Healthy Living Behavior (PHBS) is an important component in creating healthy living habits, especially in elementary school children. Education about PHBS needs to be instilled from an early age to form a sustainable healthy lifestyle. This study aims to determine the effect of interactive education on improving the understanding of second-grade students at Dharma Loka Elementary School Pekanbaru regarding PHBS. In this study, 50 students were involved using a pre-experimental design through the One Group Pretest-Posttest Design method. The educational intervention was carried out using interactive instructional games such as snakes and ladders, animated films, and PowerPoint presentations. The results showed an increase in students' understanding of PHBS after the intervention. The average score of students in the initial test was 93.2, while after the intervention, the average score increased to 100, with an increase of 6.8 points. This indicates that interactive learning has a positive impact on students' understanding of PHBS. Learning that involves teaching aids and games is proven to be more interesting for elementary school students, making them more active in the learning process. Interactive education not only improves students' understanding but also encourages them to apply PHBS more in their daily lives. The use of media such as games, animated films, and PowerPoint presentations facilitates a more comprehensive and enjoyable understanding. Therefore, this approach can be an effective strategy for teaching children healthy lifestyles, while providing a fun and rewarding learning experience. This interactive education also provides students with the opportunity to learn in a more enjoyable and less boring way. Through the snakes and ladders game, students can learn the concept of healthy living (PHBS) directly in a lighter and more entertaining way. Animated films and PowerPoint presentations add variety to the learning method, making the information conveyed more easily by students.

In its ideal form, punishment is conceived as a rational and proportionate response to moral wrongdoing, grounded in demonstrable harm and clear culpability. Classical penological theories emphasize the principles of retribution, deterrence, rehabilitation, and incapacitation, all of which presume the presence of intent and injury. However, in the case of Tom Lembong, punishment was imposed absent any proven crime, malicious intent, or measurable harm. Instead, it became a symbolic act, reconfigured as a performance of political theater to assert and preserve a sovereign narrative. This article advances two interrelated aims. First, it analyzes how the penalization of Tom Lembong reflects a wider pattern wherein legal institutions are repurposed to perform sovereignty and construct legitimacy through public spectacle. Second, it critiques the inadequacy of classical penological frameworks when punishment operates without moral fault or corrective intent. Using a qualitative research method and conceptual approach, this study draws upon library-based data sources, critically engaging with theoretical literature on penology, sovereignty, and post-truth politics. Data analysis was conducted descriptively, allowing conceptual mapping between legal practices and political narratives. The findings indicate that the punishment in this case functioned less as an instrument of legal redress than as political choreography. It transformed into symbolic currency designed to enforce narrative conformity and signal power consolidation. In such contexts, punishment serves not as a corrective measure but as a performative mechanism, signaling the dominance of a political order over competing interpretations of truth. This rupture in classical penological logic calls for a post-penological framework—one that accounts for punishment as a tool of narrative enforcement and symbolic governance within post-truth legal orders. Such a framework recognizes the transformation of legal acts into staged political performances, where the appearance of justice supersedes substantive fairness.

This study discusses the symbolic meaning contained in the use of figurative language in the poetry anthology Selamat Menunaikan Ibadah Puisi by Joko Pinurbo. This study uses a qualitative descriptive approach with a semiotic analysis method as a theoretical basis, which allows researchers to interpret the signs and symbols in the poetic texts in depth. The results of the study show that the figurative language in the poems does not only function as rhetorical decoration or mere linguistic ornamentation, but has a strong and essential symbolic function in conveying hidden messages and the poet's inner emotions. Symbols such as "storm", "refrigerator", "twilight", "window", "door", "river", and others are not only concrete images, but convey deep meanings related to inner suffering, past memories, the search for self-identity, feelings of alienation, and the search for the universal meaning of life. In addition, this study also identifies various types of figurative language used by Joko Pinurbo in the anthology, including metaphor, simile, personification, hyperbole, synecdoche, paradox, and irony. All types of figurative language are skillfully used to enrich the meaning of poetry and deepen the aesthetic experience of readers, allowing them to feel and reproduce the messages hidden behind the words. Thus, this study confirms that the use of figurative language in poetry is not only a literary technique, but also a powerful medium of expression and a means of communicating complex meanings in modern literary works. This study discusses the symbolic meaning contained in the use of figurative language in the poetry anthology Selamat Menunaikan Ibadah Puisi by Joko Pinurbo. This study uses a qualitative descriptive approach with a semiotic analysis method as a theoretical basis, which allows researchers to interpret the signs and symbols in the poetic text in depth.

This study discusses the symbolic meaning contained in the use of figurative language in the poetry anthology Selamat Menunaikan Ibadah Puisi by Joko Pinurbo. This study uses a qualitative descriptive approach with a semiotic analysis method as a theoretical basis, which allows researchers to interpret the signs and symbols in the poetic texts in depth. The results of the study show that the figurative language in the poems does not only function as rhetorical decoration or mere linguistic ornamentation, but has a strong and essential symbolic function in conveying hidden messages and the poet's inner emotions. Symbols such as "storm", "refrigerator", "twilight", "window", "door", "river", and others are not only concrete images, but convey deep meanings related to inner suffering, past memories, the search for self-identity, feelings of alienation, and the search for the universal meaning of life. In addition, this study also identifies various types of figurative language used by Joko Pinurbo in the anthology, including metaphor, simile, personification, hyperbole, synecdoche, paradox, and irony. All types of figurative language are skillfully used to enrich the meaning of poetry and deepen the aesthetic experience of readers, allowing them to feel and reproduce the messages hidden behind the words. Thus, this study confirms that the use of figurative language in poetry is not only a literary technique, but also a powerful medium of expression and a means of communicating complex meanings in modern literary works. This study discusses the symbolic meaning contained in the use of figurative language in the poetry anthology Selamat Menunaikan Ibadah Puisi by Joko Pinurbo. This study uses a qualitative descriptive approach with a semiotic analysis method as a theoretical basis, which allows researchers to interpret the signs and symbols in the poetic text in depth.

Electronic commerce (e-commerce) has become a dominant trend in modern buying and selling transactions, offering easy access and efficiency. Marketplaces like Shopee act as intermediaries between merchants and buyers, providing fast, secure, and integrated transaction facilities. However, behind this convenience, significant legal issues arise, particularly regarding unilateral transaction cancellations by buyers through the refund feature. In practice, these refund requests are generally approved by the marketplace without thorough verification of the validity of the cancellation reason or the existence of the goods already shipped by the merchant. This study aims to analyze the legality of unilateral cancellations by buyers from the perspective of Indonesian civil law, with reference to the provisions of the Civil Code (KUHPerdata) and the concept of electronic contracts as stipulated in the Electronic Information and Transactions Law (UU ITE). The study uses a normative juridical approach by examining laws and regulations, legal literature, and analyzing two case studies involving merchants BZS and HK. The results indicate that unilateral cancellations by buyers without returning the goods constitute a form of breach of contract. This action not only violates the electronic contractual agreement established during the transaction but also causes financial and reputational harm to merchants. This phenomenon indicates weak legal protection for business actors in the e-commerce ecosystem, particularly regarding the bargaining power between sellers, buyers, and marketplace platforms. Therefore, strengthening fair and transparent digital dispute resolution mechanisms is necessary, including preventive legal protection to prevent losses and repressive protection to provide redress for injured parties. This step is crucial for realizing a healthy, balanced, and equitable digital trade ecosystem for all parties involved.

This research is motivated by the phenomenon of violence experienced by individuals in the early adulthood age range (18–25 years), which is often a manifestation of unresolved traumatic experiences. Unmanaged trauma can have profound psychological impacts, affecting an individual's identity, social relationships, and outlook on life. However, within the framework of positive psychology, there is the concept of Post Traumatic Growth (PTG), which explains the potential for psychological growth that can emerge after an individual experiences severe stress or trauma. PTG includes positive changes in oneself, increased meaning in life, personal strength, and appreciation for life. The concept of PTG is the main foundation in the creation of abstract sculptures that attempt to represent the psychological journey of victims of violence, from destructive conditions to recovery and self-awareness. Abstract forms are used as a visual medium to reflect inner conflict, identity fragmentation, and the complex process of internal transformation. The choice of abstraction allows for free expression of realistic forms, thus presenting a profound symbolic interpretation. The method of creation of the work is carried out through an artistic approach that emphasizes the exploration of form, texture, material, and space in three-dimensional expression. This process not only produces visual objects but also creates expressive symbols that contain narratives of psychological healing. The sculpture is presented as a contemplative medium that invites the audience to experience, understand, and interpret the inner journey of victims of violence. The resulting creation demonstrates that abstract sculpture can be a powerful means of emotional communication, facilitating public understanding of the experience of trauma and the potential for post-traumatic growth. Thus, this work not only serves as an artistic representation of the inner dynamics of victims of violence but also serves as a reflective medium that fosters awareness of the human capacity to recover and thrive after experiencing profound suffering.

The rapid advancement of digital technology has transformed the landscape of marketing, with social media platforms emerging as powerful tools for influencing consumer behavior. This study aims to examine the impact of social media engagement, content quality, and social proof on the purchasing behavior of consumers in the catering services industry in Sichuan, China. Recognizing the dynamic nature of the digital marketplace, the research adopts a quantitative approach, utilizing a structured survey to gather data from 390 participants who are active users of social media and potential consumers of catering services. Statistical analysis reveals a significant and positive correlation between all three independent variables—social media engagement, content quality, and social proof—and consumers’ likelihood to purchase catering services. Specifically, higher levels of engagement, such as

Improving the quality of biology learning in secondary schools requires pedagogical innovations that connect academic content with real-life contexts and leverage digital technology. This study aims to analyze the effect of a contextual teaching approach assisted by interactive PowerPoint on students’ learning outcomes in the human respiratory system topic. A true experimental design with a pretest–posttest control group was employed at SMA Negeri 1 Langowan, involving two eleventh-grade classes selected through simple random sampling. The experimental class received contextual instruction integrated with interactive PowerPoint, while the control class was taught using conventional methods. Data were collected through validated achievement tests and analyzed using normality and homogeneity tests, followed by independent and paired t-tests. The results indicate a significant improvement in learning outcomes for students in the experimental class compared to the control group. The experimental group’s posttest scores were substantially higher, and the difference was statistically significant. Integrating a contextual approach with interactive visualization effectively enhanced students’ understanding of abstract biology concepts, promoted active participation, and strengthened learning motivation. These findings support constructivist theory and highlight the relevance of contextual teaching in science education aligned with the Merdeka Curriculum. The study implies the importance of implementing context-based strategies combined with simple digital media to improve biology learning effectiveness. Future research may explore its impact on non-cognitive skills such as critical thinking and scientific attitudes. Furthermore, the results of this study provide opportunities for teachers to be more creative in designing teaching materials that are not only informative but also interactive and relevant to students' lives. By utilizing media such as interactive PowerPoint, teachers can present complex biological content in a more engaging and understandable way.

Punitive populism is a political-legal phenomenon that replaces legal rationality and corrective justice with a rhetoric of power that negates the protection of human rights and the rehabilitative function of the criminal justice system. In this context, criminal policy tends to be characterized by a repressive approach that prioritizes symbolic punishment for short-term political legitimacy. Social polarization further strengthens the destructive power of punitive populism by making the issue of crime a symbolic instrument in identity conflicts, thereby losing its autonomy and submitting to an emotional, majoritarian logic. This study aims to analyze how punitive populism, as a product of the interaction between populist logic and social polarization, results in the erosion of the basic values of modern law, particularly the principles of proportionality, legal certainty, and human rights protection. Furthermore, this study also identifies structural barriers that hinder efforts to curb its expansion in criminal policy. The study uses qualitative methods with a conceptual approach. Data were obtained through library research of academic literature, legal documents, and policy analysis, then processed using qualitative analysis techniques and presented descriptively. The research findings show that punitive populism has shifted the orientation of criminal policy from a paradigm of justice and rehabilitation to a logic of punishment that is reactive to public emotional distress. The mass media, particularly within a polarized information ecosystem, plays a role in shaping distorted perceptions of crime, thereby reinforcing public demands for harsh and immediate policies. This situation creates legal vulnerability to political instrumentalism, threatens the principle of the rule of law, and deepens social exclusion of vulnerable groups. To address this, strategic steps are needed, including limiting fear-based political rhetoric, strengthening independent legal institutions, and rebuilding a criminal law paradigm based on substantive justice, inclusivity, and respect for human rights.

This community service project aims to improve the quality of street lighting around the Waringin Tunggal Studio, located in Soneyan Village, Pati Regency. As part of efforts to improve community comfort and safety, this project focuses on addressing the issue of inadequate lighting that can impact community activities, particularly at night. Inadequate lighting around the studio creates discomfort and reduces the sense of security for both studio users and the local community. The project began with a thorough inspection of the lighting conditions around the studio. The next step was to design technical solutions to improve the existing lighting system, including increasing the number of lamps and using more efficient types of lamps in terms of energy consumption and light distribution. Furthermore, good collaboration with village officials and other relevant parties was crucial for the smooth implementation of this project. The improvement process was carried out with a focus on energy efficiency and durability, ensuring long-term benefits. The results of this project showed a significant improvement in the quality and coverage of lighting around the Waringin Tunggal Studio. This improvement not only increased comfort but also increased the sense of security for studio visitors and the surrounding community. Access to the studio at night has become easier and safer, positively impacting the arts and cultural activities held there. A post-event evaluation showed increased community participation in the studio's evening events. This success demonstrates that improved lighting can encourage community participation in community activities. Going forward, it is hoped that this activity can be enhanced by utilizing renewable energy, such as solar power, to ensure optimal lighting even during power outages, thus ensuring the desirability of this activity in the future.

Dependence on fossil fuels, such as gasoline and diesel, has become a global issue that affects environmental sustainability and energy security. Increasing greenhouse gas emissions, decreasing natural resource reserves, and instability of global energy prices encourage the need for innovation in motor vehicle fuel systems. This study aims to assess fuel efficiency and engine performance on a 110 CC motorcycle with a standard compression of 10.7:1, by utilizing a mixture of RON 90 gasoline and alcohol. The main focus of the study is to compare the effect of varying alcohol content on engine power output, with mixtures of E12.5, E17.5, and E22.5. The method used is an experimental method with three variables, namely the independent variable (type and content of fuel mixture), the dependent variable (engine power), and the control variables (engine condition, temperature, and testing method). Testing was carried out using a combination of iridium spark plugs and standard spark plugs, as well as variations in Pilot Jet sizes 34 and 35 on aftermarket carburetors. Each combination was tested to determine its effect on the maximum engine power. The results showed that a blend of E12.5 fuel with Pilot Jet 35 and iridium spark plugs produced the highest power output compared to other tested combinations. This combination was proven to optimize combustion in the combustion chamber, thereby improving engine efficiency and performance. Conversely, increasing the alcohol content above E12.5 did not provide a significant increase and even tended to decrease power due to alcohol's lower calorific value than gasoline. The conclusion of this study is that the use of an aftermarket carburetor with Pilot Jet 35 and iridium spark plugs, combined with an E12.5 fuel blend, can be an effective alternative for improving the performance of a 110cc motorcycle. These findings are expected to serve as a reference for the development of more efficient and environmentally friendly blended fuel technology.

This research explores the engineering and performance evaluation of 17-4 PH stainless steel as a potential material for turbine blades in geothermal power plants (PLTP). To promote renewable energy innovation in industrial engineering, this study focuses on improving material reliability through microstructural optimization and mechanical property control. The material was produced using the investment casting method at PT SPVMB and then subjected to four heat treatment variations: H900, H1025, AVG (average), and as-cast conditions, with reference to ASTM A747 standards. Mechanical and corrosion characterization were performed through hardness and tensile tests, electrochemical corrosion analysis using geothermal water from the Dieng PLTP, and microstructural observation using an optical microscope. The results showed that the H900 condition had the highest hardness and yield strength (48.46 HRC and 939.25 MPa), but its corrosion rate was relatively high. In contrast, the H1025 heat treatment provides balanced mechanical strength (43.88 HRC and 860.91 MPa) with the lowest corrosion rate (0.027 mm/year), supported by a uniform tempered martensite structure. These findings indicate that heat treatment optimization significantly improves the suitability of 17-4 PH stainless steel for sustainable geothermal applications. The H1025 condition meets all the requirements for geothermal turbine blades, including hardness, strength, and corrosion resistance, potentially extending component life and reducing maintenance costs. Furthermore, the results of this study strengthen the agenda for developing durable, environmentally friendly materials to support renewable energy systems. This study also provides practical insights for industry in selecting the optimal heat treatment that combines mechanical performance and corrosion resistance in extreme geothermal environments.