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This study investigates the performance of Internet of Things (IoT)-based monitoring systems using a mobile hotspot and IoT sensors for temperature and humidity data transmission. The research is based on the IoT concept, which enables electronic devices to communicate and exchange data through internet networks without direct human intervention. System performance was evaluated using standard Quality of Service (QoS) parameters, including throughput, packet loss, delay, and jitter. The experimental setup utilized a NodeMCU ESP32 microcontroller and a DHT22 sensor, with measurements conducted at various transmission distances through wireless communication media. The objective was to determine the reliability of hotspot connectivity and sensor communication in supporting IoT applications. The results indicate that the optimal performance was achieved at a distance of 20 meters using a 40-lambda variation. Furthermore, the communication signal between the ESP32 device and the mobile hotspot remained detectable up to a maximum distance of 32 meters. These findings demonstrate the effectiveness of the proposed IoT system for environmental monitoring applications within specific transmission ranges.

  Red dragon fruit contains bioactive compounds such as vitamin C, flavonoids, and polyphenols that have antioxidant potential and possess natural pigments that can be used as cosmetic colorants. This study aims to formulate and evaluate a blush-on powder preparation from dragon fruit pulp extract as an alternative natural colorant. The evaluation includes organoleptic testing, homogeneity, pH, irritation, spreadability, fineness, moisture content, and antioxidant activity. The results showed that the formulation met most of the requirements, exhibiting a pink color, a smooth texture, no odor, homogeneity, a pH of 6 suitable for the skin, no irritation, even spreadability within 4 applications, a fineness degree of 97.6%, and a moisture content of 6.91%. Antioxidant activity showed an IC₅₀ value of 0.3036 ppm (very strong), although the relative inhibition percentage was low (18.35%). Thus, dragon fruit extract has the potential as a natural ingredient in blush-on powder that provides both color and antioxidant benefits.

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.

This review article evaluates the physical characteristics and stability of Oil in Water (O/W) and Water in Oil (W/O) creams through a comparative literature study published between 2021 and 2026. The evaluation focuses on important parameters, including viscosity, spreadability, adhesion, pH, and accelerated stability testing. The findings reveal that O/W creams generally have lower viscosity and greater spreadability, making them more suitable for daily cosmetic and therapeutic applications due to their lighter texture and better aesthetic acceptance. In contrast, W/O creams demonstrate higher physical stability, stronger adhesion, and superior occlusive properties, which are beneficial for protecting sensitive active ingredients and maintaining skin hydration over longer periods. The differences in performance are strongly influenced by the optimization of emulsifier Hydrophilic-Lipophilic Balance (HLB) values and the ratio between oil and water phases. Both cream types show good biocompatibility with skin pH ranging from 4.5 to 6.5, indicating their safety and effectiveness for topical pharmaceutical and cosmetic formulations.

The rapid development of technology in the era of the Industrial Revolution 4.0 has driven the education sector to continuously adapt to the evolving demands of digital-based industries. One of the key technological innovations supporting this transformation is the Internet of Things (IoT), which enables data acquisition, real-time monitoring, and remote control of systems through internet networks. In response to these developments, a community service program was conducted to enhance the understanding and technical skills of students at SMK Negeri 1 Sindang through the provision and utilization of an IoT Trainer Kit Simulator as a practical learning medium. This activity aimed to bridge the gap between theoretical knowledge and industry-relevant technological applications by introducing students to hands-on IoT system implementation. The program included demonstrations and guided practice on the use of sensors, microcontrollers, and web-based monitoring platforms to simulate real-world industrial scenarios. The results indicate that students showed high enthusiasm and active participation throughout the activity. Moreover, participants were able to grasp the fundamental concepts of IoT systems, understand component integration, and recognize the relevance of IoT applications in supporting automation and digital transformation. Overall, this community service activity contributed positively to strengthening students’ digital competencies and preparedness for the demands of the contemporary industrial and technological landscape.

This community service activity aims to design a prototype of a web-based Intellectual Property Rights (IPR) registration information system at the South Sumatra Provincial Industry Office as an effort to support the improvement of public service quality. The main problem faced by partners is the manual registration and management process for IPR data, which has the potential to cause service delays, data recording errors, and difficulties in monitoring the status of IPR applications. This condition requires an information technology-based solution that can improve the efficiency, effectiveness, and transparency of services. The method used in this community service activity is the prototype method, which includes the stages of problem identification, user needs analysis, system design, and initial evaluation of the resulting prototype. The designed information system prototype includes features for online IPR registration, applicant and document data management, and application status monitoring. The results of the activity indicate that the IPR registration information system prototype is able to provide an overview of digital solutions that are in accordance with partner needs and have the potential to improve service efficiency and ease of data management. This activity is expected to become the basis for the development of a more comprehensive and sustainable IPR information system within the South Sumatra Provincial Industry Office.

Natural fiber based composite materials are increasingly being developed as an environmentally friendly alternative to synthetic fiber-based composites. This study aims to characterize the thermal and mechanical properties of natural fiber composite materials and evaluate their potential use as sustainable materials. Composites are made using natural fibers as reinforcement and a polymer matrix through a specific molding method. Mechanical property characterization includes tensile tests, flexural tests, and impact tests, while thermal property characterization is carried out using thermal analysis to determine the thermal stability of the material. The test results show that the addition of natural fibers has a significant effect on improving the mechanical properties of the composite, especially tensile strength and elastic modulus, compared to the unreinforced matrix. In addition, natural fiber composites show quite good thermal stability over a certain temperature range, making them suitable for non-structural applications. Based on these results, natural fiber composite materials have the potential to be developed as environmentally friendly materials that have competitive mechanical and thermal performance.

Evidence is a fundamental element in the legal proof process that serves as the basis for judges to examine, assess, and decide cases in court. Along with the advancement of information technology, the form of evidence has evolved, including digital evidence such as screenshots of conversations through digital communication applications like WhatsApp. This study aims to analyze the legal position and evidentiary value of digital conversation screenshots within the Indonesian legal system. The research method uses a normative juridical approach by examining laws and regulations, legal doctrines, and relevant court decisions. The results indicate that screenshots of conversations have legal recognition as electronic evidence; however, their evidentiary strength is limited and requires support from other forms of evidence. Judges apply the principle of Unus Testis Nullus Testis, meaning that screenshots cannot stand alone as sole evidence and must be supported by additional legal proof to fulfill the requirements of valid, complete, and convincing legal evidence.

This study examines the juridical aspects of guardianship applications by parents to obtain permission to sell a minor’s inherited land and analyzes the judicial considerations in Decision Number 199/Pdt.P/2025/PN Blt. The research employs an empirical juridical method with a sociological legal approach. Primary data were collected through interviews and case documents at the Blitar District Court, while secondary data consist of statutes, doctrine, and related literature. Qualitative-descriptive analysis was applied to interpret the findings. The study reveals that the guardianship application process involves both administrative and judicial stages. Judges scrutinize material evidence and the probity of sale objectives, weighing important principles such as utility, legal certainty, fairness, and justice. Guardians are granted limited authority to sell a minor’s property only if it can be proven to be in the child's best interest and legal protections are assured. Recommendations include strengthening post-decision monitoring, enhancing legal outreach, improving procedural transparency, and ensuring comprehensive implementation.

The aim of the research is to find out the process of developing knowledge learning media based on Android applications.Learning media is very much needed as a tool used in practical learning.Changes in educational progress require innovation in learning media to keep them up to dat and able to overcome new problems that arise. The research method used is the R & D research and development method with the 4D model. The stages of the 4D development model are 1) Definition; 2) Design; 3) Development; 4) Distribution. This research produces android-based textile knowledge learning media. The software used is iSpring Suite Toolkit Authoring based on Power Point; and Website 2 APK Builder.The iSpring Suit software is used in the design and development of learning media, while the Website 2 APK Builder software is used to change Android application programs. Based on the results of the learning media feasibility questionnaire, it can be seen that the textile knowledge learning media is very feasible to use, reaching 90%.

This study aims to analyze the effect of Tungsten Inert Gas (TIG) welding parameter variations on the mechanical and metallurgical properties of AISI 304 austenitic stainless steel, which is widely used in construction and industrial applications due to its excellent corrosion resistance and joint strength. The research focuses on identifying the optimal welding current to minimize welding defects and enhance joint structural integrity. Welding current was varied at three levels, namely 100 A, 125 A, and 135 A, while other parameters such as welding speed, argon shielding gas flow rate, and electrode type were kept constant. Mechanical properties were evaluated through Micro-Vickers hardness testing conducted in the weld metal, Heat Affected Zone (HAZ), and base metal, as well as tensile testing to determine ultimate tensile strength and elongation. In addition, non-destructive testing using the dye penetrant method was performed to detect surface welding discontinuities. Metallographic analysis was carried out using optical microscopy following an etching process to observe grain morphology, grain size, and the formation of microstructural phases. The results are expected to demonstrate a correlation between increased heat input due to higher welding current and changes in mechanical properties and microstructure, particularly in the HAZ. This study provides practical guidance for determining optimal TIG welding parameters for AISI 304 to achieve high tensile strength, homogeneous hardness distribution, and a stable microstructure resistant to intergranular corrosion.

Catfish farming is one of the fisheries areas with great potential in Indonesia. However, the problem of feed efficiency, use of probiotics, and air temperature control are still the main obstacles that affect the health and growth of fish. This study aims to design and implement an automatic system that can regulate the provision of feed and probiotics and control and control air temperature directly using the ESP32 microcontroller. This system has several important components, such as the ESP32 microcontroller as a control center, servo motors for feed and probiotic distribution, and DS18B20 temperature sensors to monitor air temperature. All components can be controlled and viewed through an IoT-based application with a Wi-Fi connection or applications such as Telegram. This trial aims to determine whether this system can provide feed and probiotics according to the specified time, and maintain air temperature in the optimal range (28°C–40°C) for catfish growth. In this way, the system is expected to increase efficiency in catfish farming automatically, reduce the need for human labor, and minimize errors in pond management.

Technological innovation in Christian Religious Education learning strategies aims to improve students' learning literacy comprehensively. In an era of globalization and rapid technological advancement, Christian Religious Education is required to adapt to digital learning media to ensure relevance and effectiveness. The use of various technologies, such as interactive learning videos, educational applications, and e-learning platforms, increases student motivation and active engagement in understanding Christian values ​​and integrating faith with knowledge. Learning strategies using attractive digital technology, a hybrid learning model that combines face-to-face and bold learning, and improving teacher competency are key to the successful implementation of this innovation. The research method used is descriptive qualitative based on a literature review that examines relevant scientific literature, books, and documents on technological innovation in religious education and improving learning literacy. Content analysis was conducted by grouping data based on themes such as technology type, learning strategy, and its impact on student literacy. The research results show that the integration of technology in Christian Religious Education learning provides a significant opportunity to create a technologically savvy young generation that is both mature in faith and character, and able to face the challenges of the times with steadfastness.

The rapid development of information technology has increased the use of online lending services, including illegal platforms that impose excessive interest rates, misuse personal data, and employ intimidating debt collection practices. Limited legal and digital literacy has made communities more vulnerable to these risks. This Community Service Program aims to enhance the understanding of residents in Kradenan Village, Tuban Regency regarding the characteristics of illegal online loans, their social, economic, and psychological impacts, and the relevant legal protections under regulations such as the Electronic Information and Transactions Law, the Personal Data Protection Law, and OJK Regulation No. 77/2016. Through participatory legal education and interactive discussions, the program achieved full participation and improved participants’ knowledge by up to 75%. Residents became more capable of identifying illegal loan applications, recognizing data misuse risks, and understanding preventive measures and available legal remedies. This program effectively increased public awareness to use digital financial services more responsibly and avoid the dangers of illegal online lending.

Pakpak Bharat Gambir Tea MSMEs are products extracted from the young leaves of the Gambir plant. Not many people know about Gambir tea and its benefits or functions. Gambir tea products can only be found in online marketplaces, such as Tokopedia, Shopee, Lazada, Mbizmarket.co.id, and Indotrading, where Gambir tea producers are registered with the Pakpak Bharat Regency. One local exporter, Agro Lestari, sells "Gambier Leaf Tea" packaged in boxes with aluminum foil with 25 sachets. Offline sales in Pakpak Bharat Regency are still lacking, both in traditional markets, modern markets such as Indomaret, shops or stalls. Pakpak Bharat Gambir Tea, especially Gambir Sondel leaf tea, has been marketed to several regions in Indonesia, through wholesalers, trading partners and online resellers and social media such as TikTok, Facebook and Instagram, but the content does not provide an explanation of what Gambir tea is, its benefits or functions. The problem is:(1)What types of marketing strategies are effective? (2)How to design online and offline marketing? Objectives:(1)Help the process of understanding effective marketing strategies. (2)Help how to design online and offline marketing. The implementation of the lecture method is accompanied by questions and answers, demonstrations and practice. Gambir Pakpak Bharat tea UMKM carries out effective marketing strategies through market segmentation, targeted markets and fulfilled according to needs. The distribution system is through direct sales at outlets, delivery applications integrated with third-party applications such as GoFood or GrabFood, and online marketplaces as well as marketing communications using social media. and collaborating with local influencers

This study aims to design and test a Dual Axis Solar Tracker to improve the energy absorption efficiency of solar panels on ships. The system is designed with a two-axis movement mechanism (horizontal and vertical) using a linear actuator motor controlled by Arduino Nano and ESP32. Testing was conducted on a 20 WP solar panel in Surabaya for 30 days, divided into three methods: 10 days using an LDR sensor, 10 days using an RTC, and 10 days in static conditions without a sensor. Voltage, current, and power data were measured every 30 minutes at 07.00–17.00 WIB. The test results show that the RTC method provides the highest and most stable output power, according to the sun's movement patterns in tropical areas, while the LDR method responds quickly to changes in light intensity but is less stable in changing weather. Static installation produces the lowest power. This system is able to maintain the panel orientation perpendicular to the sun's rays, thus increasing energy efficiency compared to static systems. These findings prove that dual-axis solar tracker technology, especially with an RTC sensor, is effective in dynamic maritime environments and can be a practical solution for optimizing renewable energy on ships. The most effective results using RTC sensors demonstrated the most stable and high power output, especially since the sun in tropical areas like Surabaya moves fairly consistently following a cyclical pattern. The success of this system not only increases the energy output of solar panels but also provides a practical solution for renewable energy applications in tropical climates.

This study aims to evaluate the effectiveness of the Artificial Intelligence-Based Learning Media Development Program (P3MP-AI) in enhancing teachers’ technological and pedagogical competencies at SMK Muhammadiyah 2 Malang. The program employed a descriptive approach using both quantitative and qualitative methods, including pre-test and post-test assessments, as well as direct observation of the training process. A total of 30 teachers from various disciplines actively participated in the program conducted on August 12, 2025. The evaluation results revealed an increase in the participants’ average scores from 100 to 130 out of a maximum of 150, indicating a significant improvement in their understanding of AI concepts and applications in education. Beyond competency enhancement, the training also fostered teachers’ confidence, creativity, and ability to integrate AI-based tools into interactive learning media. However, several challenges were identified, such as limited technological resources and time constraints in classroom implementation. Overall, this program has made a tangible contribution to strengthening teachers’ digital literacy and can serve as a replicable professional development model for other vocational schools seeking to advance AI-based educational transformation.

This study aims to analyze the comparison of the durability of natural fiber and synthetic fiber composites in a high-temperature production environment. Testing was conducted on carbon fiber, aramid (synthetic), ramie, and jute (natural) fiber-based composites with exposure to temperatures of 80-150°C for 500 hours. The parameters measured include tensile strength, elastic modulus, dimensional stability, morphological changes, and moisture absorption. The research results show that synthetic fiber composites have superior durability compared to natural fibers. Carbon fiber composites retain 87% of their initial tensile strength with only a 4.2% reduction in modulus, while flax fibers only retain 62% strength with a 26% reduction in modulus. Microscopic analysis revealed significant delamination in natural fiber composites with interface gaps of 15-25 μm, compared to 3-5 μm in synthetic fibers. Natural fibers undergo thermal degradation due to the decomposition of lignin and hemicellulose, resulting in significant color changes and a dimensional shrinkage of 3.2%. The moisture absorption of natural fibers increases to 8.5% after exposure, indicating damage to the cellular structure. This research concludes that synthetic fiber composites are more suitable for long-term high-temperature production applications, but natural fibers can still be considered for low-temperature applications with appropriate chemical modification.

Bintan Island has abundant bauxite soil resources; however, its utilization as road construction material remains limited. The scarcity of high-quality granular material in the region necessitates the use of available local resources, particularly for pavement subgrade layers. This article aims to analyze the classification and mechanical properties of native soils in Bintan Island through a systematic literature review. The reviewed literature includes laboratory test results of bauxite soil. The findings indicate that bauxite soil exhibits low plasticity, relatively high CBR values (±35%), and is classified as CL (USCS) and A-2-4 (AASHTO). These results suggest that bauxite soil is suitable for subgrade applications, although require stabilization with binding agents. The implication of this review highlights that the utilization of local materials could support sustainable infrastructure development in island regions by reducing dependency on imported materials.  

Lemongrass (Cymbopogon citratus) is a plant known to contain various bioactive compounds with potential antioxidant properties as well as xanthine oxidase (XO) inhibitory activity. This study aimed to evaluate the phytochemical content, antioxidant activity, and XO inhibitory potential of ethanol extracts from the leaves, stems, and their combination. Phytochemical screening revealed that all extracts contained alkaloids, flavonoids, and terpenoids, while phenolic compounds were detected only in the leaf extract and the combined leaf–stem extract. Antioxidant activity assays demonstrated that all extracts exhibited very strong antioxidant activity, with IC₅₀ values below 50 ppm, indicating a significant potential to scavenge free radicals. In the XO inhibition assay at a concentration of 200 ppm, the ethanol extract of lemongrass stems showed the highest inhibitory activity at 81.37%, followed by the leaf extract at 48.08% and the combined leaf–stem extract at 33.65%. Overall, these findings suggest that the ethanol extract of lemongrass stems is the most promising natural source of antioxidants and has the greatest ability to inhibit xanthine oxidase activity, indicating its potential development as a functional ingredient for health applications.