The global demand for energy, particularly fuel oil, continues to increase along with the growth in the number of vehicles and industrial activity. However, limited fossil fuel reserves and the environmental impacts of their use have prompted various studies to find alternative fuels that are more environmentally friendly, efficient, and sustainable. In this context, ethanol and xylene have emerged as two potential fuel additive candidates. Ethanol is known as a biofuel derived from renewable sources and has a high octane rating and oxygen content that can support a more complete combustion process. On the other hand, xylene is an aromatic compound with a high octane rating that can improve combustion stability and reduce the risk of knocking or detonation in engines. This study aims to evaluate the effect of ethanol and xylene additions on the flame characteristics of Pertamax fuel, particularly in terms of flame duration and height. Through a laboratory experimental approach, observations were made on the combustion process of pure Pertamax and several fuel blends with varying ethanol and xylene contents. The results showed that pure Pertamax produced a flame with an average duration of 0.734 seconds and a flame height of 4.5 cm, while one of the best blends, namely the fourth blend containing ethanol and xylene, produced a flame duration of 1.084 seconds and a flame height of 5.7 cm. These findings indicate that the addition of ethanol and xylene can significantly improve combustion performance. These results not only enrich knowledge regarding the combustion characteristics of blended fuels, but also open up opportunities for the development of alternative fuel formulations that are more environmentally friendly, energy efficient, and support reducing dependence on fossil fuels in the future.

This study aims to identify various types of hazards found in the Apron of Juanda International Airport Surabaya and analyze their impact on flight operational safety. The apron is a vital area in aviation activities because it is a parking lot for aircraft, the process of boarding and dropping passengers, loading and unloading cargo, and light maintenance activities. The existence of potential hazards in this area can have a direct effect on flight safety if not handled properly. The research method used was qualitative descriptive with data collection techniques through field observations, interviews with apron officers, and documentation during the implementation of On The Job Training. The data obtained is then analyzed to identify potential hazards and evaluate the level of risk. The results of the study show that there are still hazard findings in the apron area, including Foreign Object Damage (FOD) in the form of foreign objects that have the potential to damage aircraft engines, oil or fuel spills that can cause fires, the presence of wild animals in the aircraft movement area, Ground Support Equipment (GSE) that is parked out of place so as to interfere with aircraft movement, and marshalls who do not use Complete Personal Protective Equipment (PPE).  This problem is caused by the weak supervision of the Apron Movement Control (AMC) unit and the low awareness of personnel in implementing a work safety culture. Based on these findings, the author prepared mitigation measures in accordance with the guidelines of Doc 9859 AN/474 concerning the Safety Management Manual, including increasing supervision, enforcing safety standards, and periodic training for all apron personnel. It is hoped that the results of this study can be an evaluation reference for airport management to strengthen the supervision system, reduce the risk of accidents in the apron area, and build a better and sustainable work safety culture.

The digital design of cultural museums with an interactive and educational approach in Indramayu Regency aims to present a modern, innovative, and interesting cultural preservation space. This concept was born from the urgent need for a means that are able to preserve, document, and promote local cultural wealth in the midst of the rapid flow of globalization. The lack of cultural literacy among the public, especially the younger generation, as well as the loss of historical objects due to inadequate storage facilities, are the main reasons for the importance of developing digital-based museums. Through an interactive approach, visitors can actively engage with cultural collections using advanced technologies such as augmented reality (AR), virtual reality (VR), and interactive multimedia. This technology provides an immersive, engaging, and personalized learning experience, so that visitors not only see, but also virtually experience the richness of the culture on display. Meanwhile, the educational approach is designed to create an informative, collaborative, and fun learning environment, which is highly relevant for learners and the younger generation as the successors of cultural preservation. Indramayu Regency, known for its long history, maritime traditions, and distinctive coastal culture, has great potential to become a center for cultural education. This digital museum will utilize digital technology to document cultural narratives in depth, so that it can be accessed not only by local people, but also national and international tourists. With its strategic location in the city center, the presence of this museum is expected to encourage the participation of the public and tourists in understanding, appreciating, and preserving the local culture of Indramayu. Apart from being an educational facility, this museum is expected to be able to become a driver of local tourism that makes a positive contribution to the economy of the surrounding community. Digital cultural museums are not only a place for preservation, but also a symbol of a strong regional identity, reflecting the synergy between technological innovation and commitment to cultural sustainability in the modern era.

The CSR program is a business commitment to act ethically, legally, and contribute to improving the quality of life of the workforce as well as their families, local communities and the wider community. According to Marnelly (2012), the CSR concept involves responsible partnerships between government, companies and local communities that are active and dynamic. CSR is an action carried out by business actors or stakeholders through responsible behavior towards society. Business people focus their attention on 3 things, namely economic, social and environmental. This is focused as a mutually sustainable activity and improving reputation is one way to prevent crises (Sari, 2010)

Turtles are integral components of two ecosystems, both coastal and marine. They play a crucial role in maintaining a healthy marine ecosystem. A nutritious sea fosters millions of fish, serving as a significant protein source for humans. However, this is increasingly at odds with the presence of turtles, which are gradually becoming endangered. This issue stems from various factors, including large-scale commercial fishing activities near turtle nesting sites and worsening climatic changes. These factors have the potential to disrupt the balance of marine ecosystems. The approach adopted in this design is an ecological architecture approach. It aims to restore turtle habitats in coastal conservation areas to attract nesting turtles and sustainably develop tourist facilities that harmonize with the surrounding environment.

Most of the employees in this home industry are men who live around the home industry. With this business, it becomes a source of income or additional income for the surrounding community and becomes a new job opportunity for the community or teenagers who do not attend high school but have skill

This The maintenance objectives of a C6240A-type lathe involve a number of crucial aspects, including gears, tool bits, toolposts, lower sled and upper sled. This study was to investigate effective maintenance strategies for each of these components, focusing on preventive and predictive maintenance. Gears: Regular lubrication is also necessary to ensure smooth gear movement and prevent excessive friction that could lead to failure. Chisel Bits: Monitoring the condition of the tool blade needs to be done regularly. Toolpost: The toolpost needs to be checked periodically to ensure availability and safety of the cutting tool. Bottom and Top Slings: Maintenance of the lower and upper slings involves checking for tension and wear. C6240A type lathe users can minimize the risk of failure, improve operational efficiency, and extend the life of the machine. The method used in this research is a qualitative method, by means of observation and interviews. The results of this study are that the gears can be more durable because lubrication is always given and not easily thirsty, the tool blade is not easily blunted because the workpiece is fed little by little, and frequent honing is done to keep it sharp. The locking toolpost is not easily damaged if you use a rubber hammer when locking, the bottom row makes a change of ashock so that it can do automatic turning. This maintenance can increase the life of the lathe for longer operation.

The amount of load on the vehicle requires a balance current and voltage. To fullfill the requirement, vehicle use a energy stroage media called lead acid battery. Although the lead acid battery have a impaccable durability, the performance will be decrase as long as use, especially in term of power and durability. The downgrade performance from the battery make high cost replacement, meanwhile there is a change to fix the battery. One of the methode to fix is replace the cell and added H?SO? electrolyte concentrat variation. This research intend to examine repairment effectivity and electrolyte concentrat variation on power for used lead acid battery NS40 type. H?SO? electrolyte that used is 30%,40% and 45%  examine with 5 static dummy load 1 ? 100 W pararrel circuit. Each electrolyte examine 60 times to obtain performance and durability data. The results show that increasing the concentration of H?SO? has a significant effect to produce the voltage and current. At 30% concentrate, an average voltage is 9.8 V and the current is 30.125 A at 40% concentarte, the voltage is 10.18 V and the current is 32.731 A and at 45% concentrate, the voltage is 10.19 V and the current 33.375 A.

The research took place at Wastec Internasional Company, a company engaged in environmental waste processing services. The oil from the crude oil waste processing treatment process still has Basic Sediment and Water (BS&W) content and oil content that is too high so that it cannot reach the established standards so that the company must make efforts to reduce waste from the production process. The purpose of the study was to determine the sigma value, the number of defects and factors causing quality failure in crude oil processing treatment at PT Wastec Internasional. The methods used are the DMAIC method, control maps and fishbone diagrams. The calculation results obtained an average BS & W sigma value of 3.4 and an oil content sigma value of 3.29. The average number of defects for BS&W was 9.075% and for oil content was 2113 mg/L. The factors causing treatment quality failure are material, method and environmental factors.

Mining roads play an important role in supporting the smooth running of mining activities, especially in the process of transporting materials. The bearing capacity of the soil as a road subgrade greatly affects the stability and resistance of the road to heavy equipment loads. This study aims to analyze the effect of the plasticity index and compaction parameters on the California Bearing Ratio (CBR) value, as well as to determine the thickness of the road layer based on the laboratory CBR value. Testing was carried out at the South Pit of PT. Bina Sarana Sukses site PT. Baramulti Suksessarana with a field test method using the Dynamic Cone Penetrometer (DCP) and laboratory tests such as proctor tests, Atterberg limit tests, and CBR tests on various variations of clay and sand soil mixtures. The results showed that increasing the plasticity index decreased the CBR value, while increasing the maximum dry density and decreasing the optimum water content increased the CBR value. Based on the laboratory CBR value, recommendations were obtained for the appropriate road layer thickness to ensure optimal bearing capacity for heavy equipment passing through the research area.