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This study aims to estimate coal resources using the kriging method at PT. Inti Bara Perdana, Taba Penanjung, Bengkulu. Geostatistical analysis was applied to evaluate spatial variability of coal quality parameters, including total moisture (TM), inherent moisture (IM), ash content (ASH), volatile matter (VM), fixed carbon (FC), and calorific value (CV). The research utilized drilling data with an average spacing of 80 meters. Variogram modeling was conducted using SGeMS software, employing spherical models to determine nugget, sill, and range parameters. The results show a low nugget effect (0%) indicating strong spatial continuity. The obtained ranges vary between 180–1296 meters depending on the parameter. Blo./ck kriging estimation was performed using block dimensions of 25 × 25 × 8 meters and a coal density of 1.3 ton/m³. The total estimated coal resource up to an elevation of 230 m is 253,500 tons. These findings demonstrate that kriging provides reliable resource estimation and supports mine planning optimization. This research contributes to improving coal resource evaluation accuracy and operational decision-making in open-pit mining.

The conversion of agricultural land to non-agricultural land continues to increase along with the pressures of urbanization, industrialization, and settlement expansion. This condition poses risks to food security, environmental sustainability, and farmer welfare. This article reviews literature based on 25 abstracts/research results on LP2B in Indonesia to map policy implementation patterns, the relationship between LP2B and regional spatial planning, inhibiting factors, and the direction of policy strengthening. The method used is a narrative review with thematic synthesis of normative legal studies, juridical-empirical, qualitative, mixed methods, and spatial-quantitative approaches. The results of the review indicate: (1) LP2B is highly dependent on the harmonization of spatial planning policies, especially RTRW/RDTR and licensing mechanisms based on KKPR-OSS; (2) many regions are still stuck at the land inventory-identification stage, not yet reaching the determination and operational protection through LP2B Regional Regulations; (3) dominant obstacles include regulatory asynchronous, weak law enforcement, minimal cross-agency coordination, limited data by name by address, suboptimal socialization, and conflicts of interest in non-agricultural development; (4) incentive-disincentive instruments have not been implemented consistently, although socially farmers tend to accept LP2B protection; and (5) quantitative evidence at the national level shows that LP2B policies have a positive effect on the percentage of rice fields, despite being suppressed by population density and real estate sector growth. This article emphasizes the need for an integrated spatial governance approach, strengthening regional institutions, and designing policies that are socially and environmentally just to ensure that LP2B is effective in maintaining regional food security.

This study explores the intellectual structure and research trends surrounding ethnocentrism in multinational corporations (MNCs) through a bibliometric mapping approach, with particular attention to cross-cultural management and workforce diversity studies. An initial dataset of 200 records was retrieved using Publish or Perish from Google Scholar and Crossref, of which 96 peer-reviewed journal articles published between 2020 and 2025 were retained following a PRISMA guided screening process. Bibliometric analysis was conducted using VOSviewer to examine keyword co occurrence, network relationships, and thematic density. The results indicate that ethnocentrism functions as a central organizing concept within the literature, closely associated with cultural differences, expatriation, workforce diversity, and organizational practices in multinational contexts. Temporal patterns observed in overlay and density visualizations suggest a growing scholarly emphasis on practice-oriented and context-specific perspectives, particularly in relation to managerial and organizational implications in global operations. Overall, this study offers a structured synthesis of existing research, highlights emerging thematic directions, and provides a foundation for future empirical and comparative inquiries into cultural diversity management in multinational corporations.

This study evaluates the implementation of spot-check testing for road preservation works in Manado City, specifically on the Kairagi–Mapanget segment, the Manado City–Wori boundary, and the Liwas Terminal Access Road, to identify existing problems and assess the effectiveness of engineering-based mitigation efforts. The objective is to examine construction quality compliance with technical specifications and identify operational challenges encountered on site. The methodology encompasses the measurement of asphalt layer thickness and density via a core drill, the examination of contract documents, the analysis of laboratory test results, and the execution of field observations. The findings show that most samples meet the required standards, although several locations require corrective action. Challenges arise from weather conditions, heavy traffic, equipment limitations, and the need for adaptation to updated technical regulations. Operational mitigation strategies, staff training, the use of core drill technology, and digital documentation were found to enhance accuracy and efficiency in evaluation. The research demonstrates the value of stakeholder collaboration and capacity building in supporting quality control for road preservation works. A multidimensional approach is effective in resolving technical and operational complexities in urban road projects.

The white shrimp (Litopenaeus vannamei) is one of the popular marine shrimp species in aquaculture due to its adaptability to various environmental conditions, including a wide range of salinity, and its omnivorous feeding behavior. This study aims to determine the effect of different combinations of stocking density and salinity on the growth rate and post larval survival of vaname shrimp (Litopenaeus vannamei). The research was conducted using factorial planning based on two factors namely stocking density (3, 6, and 9ekor/L) and salinity (15 ppt and 25 ppt). Parameters measured included daily growth rate, absolute weight, survival rate, feed utilization efficiency, and feed conversion ratio (FCR). Water quality observations were also made during the study period including temperature, pH, dissolved oxygen, salinity, and total ammonia. The results showed that the combination of stocking density of 3 fish/L with salinity of 25 ppt gave the best results with a daily growth rate of 0,00664 gram and a survival rate of 86%. This treatment also produced the best feed utilization efficiency of 0.87 and the best FCR value of 1.27, indicating the most efficient use of feed. Water quality parameters during the study were within the appropriate range to support the growth of vanamei shrimp.

Whiteleg shrimp (Litopenaeus vannamei) is one of the species that is a national superior commodity. The traffic of shrimp between provinces in Indonesia showed a significant increase in the period 2014-2017 with an average growth of 74.48% per year. Things that need to be considered in distribution activities are determining the number of seeds to be transported, providing oxygen in the packaging container, optimizing the use of low temperatures to suppress metabolic activity. This study was conducted with the aim of determining different densities on survival and determining the optimal density for the survival of whiteleg shrimp (Litopenaeus vannamei) in closed transportation for 36 hours. The method in this study used an experimental method with data collection carried out through direct observation. The experimental design used in this study was a Completely Randomized Design (CRD) with 5 treatment combinations. Density consisted of 1500 individuals/2 liters, 2000/2 liters, 2500 individuals/2 liters, 3000/2 liters and 3500 individuals/2 liters. The main parameters observed were survival and the test parameters measured were DO, temperature, salinity, and pH. The results showed that the best performer was in Treatment (B) with a density of 2,000 individuals with a survival rate of 86.02%. The results of the air quality observation study showed that almost all were still at optimal levels to support the survival of whiteleg shrimp (Litopenaeus vannamei) with an average temperature of 26.22°C. pH 7.18 – 8.08. Dissolved oxygen 3.87 – 8.06 ppm.

This research investigates thermal material properties and performance characteristics for high-speed vessel components subjected to extreme thermal stress during sustained high-speed operations. High-speed vessels including patrol boats, fast ferries, and naval craft experience elevated thermal loads from high-power density propulsion systems, aerodynamic heating, and sustained operational intensities creating demanding conditions for structural and mechanical components. Through qualitative analysis involving naval architects, materials engineers, high-speed vessel operators, and component manufacturers, this study examines how material thermal properties affect component durability, performance, and safety while identifying optimal material selections for critical applications. Results demonstrate that advanced thermal materials including high-temperature aluminum alloys, titanium alloys, ceramic composites, and thermal barrier coatings can extend component service life by 40-70%, improve thermal management effectiveness by 25-45%, and enhance operational reliability compared to conventional materials. Key implementation challenges include material cost premiums of 150-300%, manufacturing complexity, limited operating experience, qualification testing requirements, and supply chain constraints. Findings reveal that strategic thermal material selection for critical components represents essential enabling technology for high-speed vessel performance, reliability, and operational availability supporting defense, commercial, and emergency response applications requiring sustained high-speed capabilities. This research contributes to marine materials engineering literature by providing evidence-based frameworks for thermal material selection applicable to diverse high-speed vessel applications.

In demographic studies, population growth refers to changes in the number of inhabitants over a given period, measured by calculating numerical differences in population size and expressing them within specific time units to illustrate patterns of increase or decline. Based on data from Tembalang District in Figures 2025, the population growth rate in Kedungmundu Village rose by 0.51% between 2016 and 2025, with most residents relying on clean water services provided by PDAM Tirta Moedal as their primary source of drinking water. This study aims to estimate clean water demand based on projected population growth and to design a pipeline network system capable of meeting future needs. The analysis of water demand applies population projection methods, including arithmetic, geometric, and least square approaches, to compare their levels of accuracy, while the clean water distribution network is modeled using EPANET 2.0. One of the main challenges faced by PDAM is that service coverage has not yet been fully optimized. The ten-year projection results indicate that the arithmetic method provides a correlation value closest to 1, estimating a future population of 14,904 people with a total clean water requirement of 3.48 liters per second. To support this projected demand, the proposed network design utilizes High Density Polyethylene (HDPE) pipes with diameters of 12, 10, and 8 inches to ensure efficient and sustainable water distribution.

Household plastic waste remains a serious challenge in urban environments, including Jl. Assofa II, Kebon Jeruk, West Jakarta, which is characterized by high population density and intense socio-economic activities. The low level of public awareness in sorting and managing plastic waste, particularly bottle caps, highlights the need for educational approaches from an early age. This community service activity aimed to enhance environmental awareness, creativity, and character development among children through the “Recycled Keychain” project, which involved recycling plastic bottle caps into keychains. The activity was implemented using a Project-Based Learning (PjBL) approach and involved 12 children aged 7–9 years as the main participants. The implementation methods included education on waste management based on the principles of reduce, reuse, and recycle (3R), collection and sorting of bottle caps, and the process of creating creative products. The results showed an increase in children’s environmental awareness and environmentally responsible behavior, the creation of eco-friendly educational products, as well as improvements in creativity, motor skills, and teamwork abilities. In addition, this activity supported the strengthening of the Pancasila Student Profile, particularly in the dimensions of cooperation, critical thinking, creativity, and independence. Overall, the Recycled Keychain project proved to be an effective model of contextual, participatory, and sustainable environmental education in instilling environmental care values from an early age in urban communities.

Decoction is a traditional extraction method rooted in ethnobotany; however, meeting quality standards in modern pharmaceutical research remains a major challenge. This study aims to map global research trends regarding phenolic and flavonoid compounds in decoctions over the 2015–2025 period through bibliometric analysis. Data were retrieved from the Scopus database and analyzed using VOSviewer 1.6.20 software, employing the fractional counting method to ensure a more proportional weighting of keyword relationships. The results indicate a fluctuating trend that significantly increased toward the end of the period, peaking at 78 documents in 2025, with India and China emerging as the primary contributors. Network visualization and research density analysis reveal that the global research focus remains centered on antioxidant capacity (DPPH, TPC, and TFC), while decoction itself occupies a supporting position within the research map. This study concludes that decoction has not yet become a central focus in modern pharmaceutical research but serves primarily as a vehicle for presenting active compounds. There remains a significant gap between traditional decoction use and the application of advanced analytical technologies such as HPLC and antibacterial testing, representing a substantial opportunity for future research to validate the safety and efficacy of decoctions more scientifically and through standardized approaches.

This study analyzes the design of the width and rigid pavement of the road on Sp. Brongkos – Ngembul, Kesamben District, Blitar Regency, along 4.5 km with an existing road width of 5 meters, rumija 16.8 meters. The surrounding area includes forestry, residential, plantation, industrial, and Jolosutro Beach tourist access, with increased traffic density during the holiday season and industrial operations. The method used is descriptive quantitative based on LHR and CBR data. The calculation of lane width using MKJI 1997 (Indonesian Road Capacity Manual) shows the need for widening of 3 meters per lane and 2 meters of shoulder. The rigid pavement design using the MDPJ 2024 method (Road Pavement Design Manual) consists of a layer of coarse-grained soil embankment, class A aggregate, lean concrete, and structural concrete with a thickness of 200 mm, 200 mm, 150 mm, and 200 mm, respectively. With the JPCP design, for the tie bar connection reinforcement with a diameter of 16 mm, a length of 700 mm, a distance of 70 cm, and a dowel with a diameter of 28 mm, a length of 45 cm, and a distance of 30 cm.

Proton Exchange Membrane Fuel Cells (PEMFCs) are increasingly developed due to their high efficiency, power density, durability, and environmental friendliness. However, the high cost of platinum catalysts limits their widespread application. Reducing platinum usage through the development of low-cost catalyst support materials is a promising approach. Activated carbon derived from biomass offers a sustainable and economical alternative, particularly when utilizing agricultural waste such as coffee husks, which are often discarded. This study aims to evaluate the characteristics of activated carbon produced from coffee husk waste through pyrolysis as a catalyst support for PEMFCs. Pyrolysis was conducted at 400 °C, followed by chemical activation using 1 M H₃PO₄ and 1 M KOH with a residence time of 90 minutes. The resulting activated carbon was analyzed through proximate analysis to determine moisture content, ash content, volatile matter, and fixed carbon content. The results showed that activation with 1 M H₃PO₄ produced the lowest moisture content (3.4%), the lowest ash content (3.8%), and the highest fixed carbon content (60.5%), while 1 M KOH yielded the lowest volatile matter content (27.7%). Based on these results, activated carbon produced using H₃PO₄ meets the requirements of SNI No. 01/6235/2000 and demonstrates strong potential as a catalyst support material for PEMFC applications.

In this study, a device was designed and implemented to control the water pH and nutrient density (concentration) in a hydroponic system using the Mamdani method of fuzzy logic, thus maintaining nutrient solution parameters within an optimal range for plant growth. This system relies on three input values ​​obtained from a water pH sensor, a nutrient TDS sensor, and a flow meter. These three sensors are used to control four peristaltic motors, each of which functions to increase and decrease the pH and nutrient levels in the solution. The speed of the peristaltic pump motor, when the water pH is set at 6.5 and the nutrient concentration is set at 700 ppm, is influenced by the difference between the sensor reading and the set point. The greater the difference, the higher the peristaltic pump motor speed. Conversely, the smaller the difference between the sensor reading and the set point, the lower the peristaltic pump motor speed. Furthermore, the amount of water flowing through the pipe also influences the peristaltic pump motor speed.

The increasing consumption of packaged food products in Indonesia reflects modern lifestyle changes but simultaneously raises public health concerns related to high calorie, sugar, and fat intake. Nutritional information presented on food labels consists of multiple interrelated variables, making it difficult to identify dominant nutritional factors that characterize packaged food products. This study aims to apply Principal Component Analysis (PCA) to reduce the dimensionality of nutritional data and to map the nutritional characteristics of packaged food products in Indonesia. The research employs a quantitative exploratory approach using secondary data obtained from nutrition facts labels of 1,651 packaged food products. Seven nutritional variables were initially analyzed, namely total energy, protein, total fat, total carbohydrates, sugar, sodium, and dietary fiber. Data preprocessing included data cleaning, Z-score standardization, and iterative variable selection based on the Kaiser-Meyer-Olkin (KMO) measure and Bartlett’s Test of Sphericity to ensure sampling adequacy and sufficient correlation among variables. Variables with low sampling adequacy and perfect multicollinearity were eliminated, resulting in five variables retained for the final PCA model. Principal components were extracted using the eigenvalue greater than one criterion and confirmed through a scree plot, followed by Varimax rotation to enhance interpretability. The results indicate the formation of two principal components explaining approximately 69.7% of the total variance. The first component represents energy density and macronutrient richness, while the second component reflects carbohydrate-related characteristics, particularly the contrasting pattern between sugar and dietary fiber. Biplot visualization further illustrates product distribution based on these components. The findings demonstrate that PCA effectively simplifies complex nutritional information and provides a clear nutritional mapping of packaged food products, offering practical insights for consumers, producers, and policymakers in supporting healthier food choices in Indonesia.

The majority of Kebomas District's residents are connected to working hours during government office hours (Monday through Friday), which creates access obstacles in administering public services due to the high population density and busy community life. In response to these time constraints, the SOS MAS (Service On Saturday in Kebomas District) invention was introduced, which offers services on Saturdays. However, the implementation of this innovation still faces challenges in the form of a low social integration rate and a restricted range of public services that have the potential to sway public opinion. The goal of this research is to assess how the SOS MAS innovation affects community happiness in Kebomas District. A quantitative technique with an associative approach is used in this research. Through an unintentional sampling method, questionnaires were given to 86 individuals in order to gather primary data. With the aid of SPSS, the determinant coefficient and a simple linear regression test were used to analyze the data. The study's findings reveal that the SOS MAS invention has a favorable and substantial influence on community happiness. The regression coefficient of 0.969 and a significance level of 0.000 <0.05 support this. The innovation variable accounted for 59.7% of public happiness, while the remaining 40.3% was impacted by variables not included in the study model, according to the coefficient of determination (R2) test. This result supports the notion that the efficacy of service innovation outside of working hours is a major element in boosting happiness for individuals with limited time. The SOS MAS innovation has been shown to greatly improve public satisfaction. Agencies are encouraged to improve their communication and outreach efforts as well as create SOS MAS innovations that maximize the advantages of innovations that meet community needs.

The objective of this study is to comprehensively examine and analyze the influence of microstructure on the mechanical properties of metallic materials. Microstructure is known to play a crucial role in determining the mechanical behavior of metals; therefore, a thorough understanding of this relationship is essential for the development of engineering materials. This study adopts a systematic literature review approach, employing descriptive analysis and meta-analysis of recent scientific publications obtained from various reputable academic databases. The analysis results indicate that microstructure is a significant determinant of the mechanical characteristics of metallic materials, including strength, ductility, and resistance to deformation. The most influential microstructural parameters include grain size, phase distribution, crystallographic orientation, dislocation density, and the presence and characteristics of precipitates. Among these parameters, grain size has been shown to be the most dominant factor. The Hall–Petch strengthening mechanism demonstrates that grain refinement can increase the tensile strength of materials by approximately 200 to 300 percent. In addition, materials with multi-phase microstructures, such as dual-phase steels and TRIP steels, exhibit an excellent combination of strength and ductility compared to single-phase materials. Based on the meta-analysis results, each metallic material system exhibits a trade-off between strength and ductility, whereby an increase in strength is generally accompanied by a reduction in ductility. These findings indicate that achieving an optimal combination of mechanical properties for specific application requirements necessitates a comprehensive and integrated microstructural engineering approach.

The increasing proportion of the elderly population in Indonesia has led to a rise in degenerative health problems, one of which is osteoporosis. Osteoporosis is a bone disease characterized by decreased bone density, increasing the risk of fractures, particularly among elderly women. Low calcium intake, lack of physical activity, and limited knowledge regarding osteoporosis prevention are major contributing factors. This community service activity aimed to improve the knowledge of Aisyiyah women in Cirebon Regency regarding osteoporosis in the elderly, including its definition, risk factors, impacts, and prevention strategies through proper nutrition and regular physical activity. The activity was conducted from October to December at the Aisyiyah Study Hall in Cirebon Regency, targeting pre-elderly and elderly women. The methods used included health education through lectures and interactive question-and-answer sessions, supported by laptops, LCD projectors, and PowerPoint presentations. Evaluation of participants’ knowledge was carried out using oral pre-tests and post-tests related to the delivered material. The results indicated an improvement in participants’ understanding of osteoporosis, the importance of adequate calcium intake, and the role of physical activity in maintaining bone health. This community service program is expected to contribute to increasing health awareness and reducing the risk and prevalence of osteoporosis among the elderly.

This study aims to apply the Principal Component Analysis (PCA) method to identify the main factors influencing poverty in North Sumatra Province. Poverty rates in this region show significant variations among districts and cities, influenced by differences in social, economic, educational, and basic facility availability. The data used in this study include eleven indicators related to population, education, health, access to basic services, and economic conditions. All variables were initially normalized to ensure they had comparable scales, then PCA feasibility tests were conducted using MSA, KMO, and Bartlett's test, which indicated that the data were eligible for further analysis. The results of the PCA revealed three main components explaining a total of 69.91 percent of the variation. The first component represents regional population and economic factors, with the largest contributions coming from population density, open unemployment rate, and per capita expenditure. The second component reflects household living conditions, such as access to clean water, adequate sanitation, and health complaints. The third component describes the educational dimension through indicators of the population aged at the primary and secondary school levels. These findings indicate that poverty in North Sumatra is influenced not only by economic factors but also by the quality of basic services and education levels among the population. Therefore, this research is useful for policymakers at the central and regional government levels to consider the factors influencing the increase in poverty in North Sumatra.

Penelitian ini mengevaluasi performa tiga algoritma deteksi komunitas Louvain, Infomap, dan Walktrap dalam konteks social network analysis pada jaringan undang-undang Republik Indonesia periode 2014–2024. Jaringan dibangun dari hubungan kutipan antar undang-undang Republik Indonesia pada rentang waktu antara tahun 2014 sampai dengan tahun 2024. Kutipan antar undang-undang diperoleh pada bagian “Mengingat” pada setiap undang-undang, menghasilkan sebuah konstruksi struktur graf berarah dan tak berbobot. Setiap algoritma diuji berdasarkan empat metrik evaluasi: modularity, coverage, conductance, dan inter-cluster density. Evaluasi terhadap tiga algoritma deteksi komunitas Infomap, Louvain, dan Walktrap pada jaringan undang-undang menunjukkan perbedaan karakteristik dalam membentuk struktur komunitas. Louvain unggul dalam hal modularity (0.522387) dan conductance (0.287157), yang mencerminkan kemampuan optimal dalam memisahkan komunitas besar yang kohesif dan minim koneksi keluar. Infomap menempati posisi menengah dengan modularity dan inter-cluster density yang cukup baik, menawarkan keseimbangan antara segmentasi dan kepadatan komunitas. Walktrap memiliki keunggulan pada coverage (0.809586) dan inter-cluster density (0.50640), menandakan kemampuannya membentuk komunitas kecil yang sangat padat secara internal, meskipun cenderung kurang terstruktur secara global karena modularity-nya paling rendah (0.464787). Dengan demikian, Louvain direkomendasikan sebagai algoritma paling sesuai untuk analisis jaringan undang-undang, terutama jika tujuan utama adalah memperoleh segmentasi komunitas yang terstruktur kuat dan representatif secara makro terhadap arsitektur hukum nasional.

This study focuses on the analysis of traffic density in Jember City, particularly at the Wirolegi Intersection, which is known to have a high density level. This condition often triggers congestion that hinders public mobility, so that appropriate and data-based handling efforts are needed. The purpose of this study is to identify and analyze the level of density at critical congestion points through a statistical approach using the One Way ANOVA method. The research method used is quantitative descriptive with a descriptive observational approach. Primary data was collected directly through a field survey in 2025 at the Wirolegi Intersection as one of 3 intersections in Jember City. The data obtained were then processed using normality tests, homogeneity tests, and One Way ANOVA with the help of SPSS software. The results of the analysis show that the traffic flow density on the three routes studied, namely Jalan Gunung Haryono, Jalan Brigjen Katamso, Jalan Yos Sudarso, does not show a significant difference. The significance value of the ANOVA test is greater than 0.05 which indicates the similarity of density levels between routes. Further testing (post hoc testing) also strengthens this finding. The conclusion of this study shows that handling congestion at the Wirolegi Intersection needs to be done comprehensively through traffic control and evaluation of the transportation system to improve smoothness and mobility in Jember City.