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Dry packing with the principle of hibernation aims to suppress the metabolic processes of an organism so that it can survive under minimal environmental conditions. This study aims to determine the effectiveness of the dry packing method on the survival of freshwater crayfish (Cherax quadricarrinatus) tested with dry packing for 15, 20, and 25 hours. Before packing, the crayfish were ensured to be healthy and free from deformities. The packing was carried out using styrofoam lined with cardboard and filled with dried banana leaves, with a density of 20 crayfish of 10 cm size per package. The results showed that packing with dried banana leaves for 25 hours resulted in a 100% survival rate after packing, and the crayfish were able to become active again after 3 days. The dry packing method using dried banana leaves was proven effective in maintaining the survival of freshwater crayfish under live conditions during long packing durations. This study contributes to the development of efficient packing techniques for transporting freshwater crayfish alive.

This study aims to analyze the difference in the volume of motorcycle traffic in the morning and evening on Jalan Dahlia which leads from the Square. The data was collected through direct observation methods during a specific period during morning and evening rush hours, then analyzed to determine vehicle flow patterns, traffic density levels, and significant differences between the two time periods. In addition, this study also considers supporting factors such as community activities, working hours, and daily travel patterns of road users that affect traffic intensity. The results of the study showed that there was a significant difference in vehicle volume, where the volume of motorcycles in the morning tended to be higher than in the afternoon due to the dominance of trips to work and school. On the other hand, in the afternoon the traffic volume is relatively more spread due to variations in the return time of road users. These findings are expected to be a reference for related parties, especially local governments and transportation agencies, in traffic management planning, transportation operational timing, and efforts to improve the safety and comfort of road users in the area.

Rock stability and service life in geotechnical and mining engineering are highly dependent on the rock's mechanical and physical parameters, where the variation in sandstone grain size is a crucial intrinsic factor. This study aims to comprehensively analyze the correlation between sandstone grain size with uniaxial compressive strength (UCS) and resistance to weathering (Slake Durability Index) in samples taken from the Balikpapan and Pulau Balang Formations in the Samarinda area, East Kalimantan. The research methodology involved a series of standard laboratory tests, including rock physical properties analysis, grain size distribution analysis, UCS testing, and slake durability testing through three cycles. The test results show a significant correlation: sandstone with finer grain sizes and higher density consistently demonstrates greater UCS values and a higher Durability Index, indicating superior mechanical and physical resistance. Specifically, the Pulau Balang Formation exhibits a more compact structure and finer grain size, resulting in better durability values compared to the Balikpapan Formation. These findings are important as a geomechanical data basis for slope design planning, rock mass stability analysis, and material selection in infrastructure projects or mining operations involving both formations.

Choosing a strategic business location is a key factor in building a successful enterprise, especially in Lautem Municipality, Timor-Leste. This area presents various opportunities for businesses such as grocery shops, small restaurants, repair workshops, and agricultural ventures. However, entrepreneurs often face challenges like poor road infrastructure, limited purchasing power, and inadequate transport access. This study developed a web-based Decision Support System (DSS) using the ELECTRE method to help business owners select the most suitable location. The system evaluates multiple location options based on important criteria such as population density, transportation access, and economic activity. By using this approach, entrepreneurs can reduce the risk of choosing an unprofitable location and improve their chances of success. The results show that implementing the ELECTRE method in a DSS is effective for identifying optimal business sites. These findings are expected to serve as a practical reference for entrepreneurs in Lospalos and nearby areas, while also supporting local economic development in the region.

Rapid developments in information technology have made laptops an essential device for students, especially those in their final year of study. Choosing the right laptop plays an important role in supporting academic productivity, such as writing theses, analyzing data, and developing software. This study aims to classify the preferences of mathematics students at Gorontalo State University in choosing laptops based on usage characteristics and factors that influence purchasing decisions. The method used is Kernel Discriminant Analysis (KDA) with a Gaussian kernel function and an optimal bandwidth of 0.8. The research data involved 268 respondents divided into training and testing data. The analysis results show that the KDA model has an accuracy rate of 60% on the training data and 52% on the testing data, which indicates the model's ability to recognize student preference patterns despite a decrease in accuracy on new data. Based on the kernel density estimation results, Acer is the most widely used laptop brand, while Zyrex and Apple are rarely chosen. The most influential factor in purchasing decisions is processor specifications, with a contribution of 35.739%, followed by brand, warranty, and price. These findings indicate that hardware characteristics are the main consideration in laptop selection, with most students choosing laptops with Intel Core i5 processors, a minimum of 8GB of RAM, and SSD storage. The results of this study can also be used by universities to provide recommendations for selecting laptops that suit students' academic needs.  

This study discusses the application of a simple experimental method using eggs and salt water as a medium for teaching basic science at MI Jam'iyatul Mubtadiin. The main objective is to improve students' understanding of the concepts of mass and buoyancy through direct experience. The research method used was a descriptive qualitative approach with fourth-grade students as subjects. The learning process was carried out through simple experimental steps: preparing fresh water, adding salt, and observing changes in the position of the eggs in the solution. Data were collected through observation, interviews, and . The results showed that this experimental method was able to attract students' interest, increase active participation, and make abstract concepts easier to understand. In addition, this simple experiment-based learning also trains students' critical thinking skills and curiosity. Thus, the use of egg and salt water experiments can be an alternative to effective, inexpensive science learning media that is suitable for the characteristics of elementary school students.

The black sea cucumber (Holothuria atra) holds significant ecological and economic value in tropical marine ecosystems, including those of Maluku, Indonesia. This study aimed to estimate population density, spatial distribution patterns, and their relationship with environmental conditions along the Haenesai coast, Hulung Village, Taniwel District, West Seram Regency. Sampling was carried out using the belt transect method (50 m × 2 m) at three stations with three replications, while physicochemical parameters of seawater (temperature, salinity, pH, dissolved oxygen, and transparency) were measured in situ. A total of 96 individuals of H. atra were recorded, with an average density of 10.6 ind/100 m². Station I exhibited the highest density (13 ind/100 m²), whereas Station II showed the lowest (9.3 ind/100 m²). Distribution patterns were generally uniform at Stations I and II, while Station III displayed a clustered pattern. These variations are likely influenced by differences in water transparency, dissolved oxygen, and substrate heterogeneity that affect food availability. Overall, environmental conditions remained suitable for H. atra, although evidence of exploitation pressure from local harvesting was observed. Ecologically, H. atra plays a critical role as a bioturbator, maintaining sediment quality and coastal ecosystem stability. This study highlights the need for regulated harvesting, habitat protection, and aquaculture development as strategic measures for the sustainable management of sea cucumber resources in Maluku.

This study evaluated the population status of the conch Strombus luhuanus at Asol Beach, , Haruku Island, Maluku, through an analysis of density, size structure, length–weight relationship, and spatial distribution. Data were collected using transect–quadrat methods in the intertidal zone during low tide, complemented by measurements of environmental parameters (temperature, salinity, pH, and dissolved oxygen). The results revealed a population density of 2.76 ind/m², classified as moderate compared to other sites in Maluku. Shell length distribution encompassed nine size classes, with dominance in the mid-size class (3.93–4.38 cm), indicating successful recruitment of juveniles to early adults. The length–weight relationship followed the equation W = 1.871L0.0521 (R² = 0.857) with a negative allometric growth pattern, suggesting that individuals allocate more energy to shell elongation than body mass increase. The Morisita index (Id = 211.07) indicated an aggregated distribution pattern, consistent with reproductive strategies of broadcast-spawning gastropods. Environmental conditions (temperature 28.7 °C; salinity 32.66‰; pH 6.44; DO 6 mg/L) were within the tolerance range of tropical intertidal mollusks. These findings highlight the critical role of sandy seagrass habitats in supporting S. luhuanus populations and emphasize the need for management strategies based on minimum catch size, harvest regulation, and coastal habitat protection.

Waste candlenut shells are one type of biomass that has significant potential to be developed as an alternative energy source, particularly in the form of briquettes. Candlenut shells, which are typically discarded as agricultural waste, contain combustible material that can be transformed into solid fuel. However, the traditional briquette molding process is still done manually, which is time-consuming, inefficient, and often results in inconsistent briquette shapes and density. This study aims to design and develop a briquette molding machine specifically for processing candlenut shell waste, with the goal of improving both production efficiency and the quality of the briquettes produced. The research methodology includes several stages: mechanical design, selection of appropriate materials, fabrication of machine components, assembly, and performance testing of the machine. The resulting machine utilizes a screw conveyor compression system powered by a 5.5 HP petrol engine. It features a cylindrical mold with a 40 mm diameter to shape the briquettes uniformly. During the performance test, the machine demonstrated a maximum production capacity of 14.3 kg per hour, with an average processing time of 24 minutes and a briquette yield reaching up to 85%. The findings indicate that the machine can significantly streamline the briquette production process while maintaining product consistency and quality. This briquette molding machine is particularly suitable for household and small-scale industries aiming to utilize renewable energy sources and reduce dependency on fossil fuels. The use of this machine also supports environmental sustainability by converting agricultural waste into a usable energy product.  

Al–Mg–Si aluminum alloys are widely utilized in engineering applications due to their low density, excellent corrosion resistance, and mechanical properties that can be modified through heat treatment. This study investigates the effect of homogenization on the microstructure and hardness of Al–Mg–Si alloys produced by the squeeze casting process. The experimental procedure involved alloy melting, squeeze casting at 76 MPa using preheated metal molds, followed by homogenization at 400 °C for 4 hours. Microstructural characterization was performed using optical microscopy to examine the dendritic morphology and measure the secondary dendrite arm spacing (SDAS). Mechanical properties were evaluated through Vickers microhardness and Rockwell macrohardness testing. The results show that homogenization increases the SDAS from 32.59 μm to 36.88 μm and decreases the volume fraction of interdendritic phases from 15.51% to 13.57%. Furthermore, microhardness decreased from 50.22 VHN to 38.58 VHN, while macrohardness decreased from 54.60 HRE to 46.64 HRE. These reductions are attributed to the partial dissolution of Mg₂Si precipitates into the aluminum matrix during homogenization. Overall, this research provides valuable insight into the optimization of initial heat treatment parameters for Al–Mg–Si alloys produced by squeeze casting. The findings highlight the role of homogenization in improving microstructural uniformity and preparing the alloy for subsequent deformation processes such as cold rolling and extrusion, particularly for structural components used in mining and heavy transportation industries.

Mycobacterium tuberculosis is characterized by a thick, mycolic acid–rich cell wall that confers hydrophobicity, chemical resistance, and environmental stability, making cell wall biosynthesis inhibitors a major therapeutic target. Tuberculosis is not only a medical condition but also a social disease linked to high population density, malnutrition, and limited healthcare access. In 2023, Kedaton District was identified as the most densely populated area in Bandar Lampung, increasing the likelihood of pulmonary TB smear-positive (TB.Paru BTA+) transmission. Aerosol spread is highly distance-dependent: direct exposure within 0–1 meter poses very high risk, and WHO reports indicate that exposure <1 meter for ≥15 minutes in enclosed spaces significantly elevates infection risk, extending up to 5–10 meters without ventilation. This study employed spatial analysis to measure inter-household distances among 75 TB.Paru BTA(+) patients using Euclidean distance and smartphone-based field surveys. The method proved suitable for small-scale studies with high data accuracy, though resource-intensive for larger populations. Findings revealed some households only 3 meters apart, but this observation was not yet statistically significant to confirm transmission dynamics.

Indonesia is a country with high lightning strike intensity, making lightning protection systems critically important, especially for public infrastructure such as Light Rail Transit (LRT). This research aims to analyze the lightning protection system implemented in the Jakarta LRT Phase 1B Project, particularly in the station areas and railway lines. The methods used include field observation, literature study, interviews, and technical analysis using the rolling sphere method, protective angle method, and mesh method to determine the coverage of protected areas. In addition, an evaluation of the grounding system was conducted to ensure the safe discharge of lightning currents into the earth. The analysis results show that the lightning protection system applied complies with PUIPP and IEC 62305-1 standards and is capable of protecting signaling and telecommunication equipment from lightning risks. The combination of the three protection methods provides comprehensive coverage for LRT structures. The grounding system design also meets the standard resistance requirement (< 5 Ohms), ensuring operational safety and protecting critical equipment. Furthermore, the study highlights the importance of integrating lightning protection with other safety systems such as fire protection and electrical surge protection, as lightning can cause cascading failures that disrupt railway operations. Proper maintenance and periodic testing of grounding resistance are also necessary to ensure long-term reliability. In addition, the Faraday cage principle applied to train cars contributes to passenger safety by preventing lightning currents from penetrating the cabin interior. This research is expected to serve as a reference for developing lightning protection systems in similar infrastructure projects, especially in regions with high lightning density. By applying international standards and comprehensive protection methods, the Jakarta LRT demonstrates how modern urban transportation can operate safely despite extreme weather risks.

Business expansion is a strategic step undertaken by companies to increase profitability while broadening their market reach. Hoka Hoka Bento (HokBen) is one of the companies that consistently implements this strategy. This study aims to identify potential locations for new HokBen outlets in Depok City by utilizing Geographic Information Systems (GIS) and spatial analysis. Several parameters were considered, including proximity to commercial and entertainment centers, competitors, educational facilities, public facilities, road networks, population density, banking services, hotels, offices, residential areas, hospitals, existing stores, and places of worship. The analysis was conducted using Euclidean Distance, Buffering, Reclassification, and the Analytical Hierarchy Process (AHP) to determine the priority weights of each criterion. These weights were then integrated through the Weighted Overlay technique to produce a location suitability map. The findings reveal that the most influential factors are commercial and entertainment buildings (0.101), road networks (0.099), and educational facilities (0.092). The resulting suitability map highlights potential areas across Depok City, particularly in zones close to community activity centers. The results demonstrate that GIS-based multicriteria analysis is effective for mapping location suitability and identifying strategic zones for expansion. Therefore, this research contributes to supporting the company’s strategic decision-making through data-driven approaches while also enriching the academic field of business geography and urban planning. In addition, the outcomes can be applied as a reference model for other fast-food chains or retail industries planning spatially optimized expansion strategies in highly competitive urban environments.

Household organic waste production in Thekelan Hamlet has increased along with population density and agricultural activities, potentially having negative impacts on the environment and health. However, this waste actually has the potential to be processed into environmentally friendly products with economic value, one of which is eco-enzymes. This community service activity aims to increase community awareness and skills in processing organic waste into eco-enzymes through a participatory approach, technical training, and live demonstrations. The main partners in this activity are housewives and village environmental cadres, who are the main targets for introducing organic waste processing techniques. During the implementation, participants were trained on the benefits and how to produce eco-enzymes independently. This activity not only provided an understanding of the eco-enzyme production process but also motivated participants to produce eco-enzymes independently at home. The results of this activity showed a significant increase in understanding of the benefits of eco-enzymes as an environmentally friendly product, which can be used as a natural cleaner and organic fertilizer. In addition, participants also began to demonstrate the initiative to produce eco-enzymes independently, which has the potential to reduce household organic waste and increase economic value through the utilization of this product. The findings from this activity demonstrate that community-based waste management can not only be an environmentally friendly solution but also has high economic value. This empowerment model can serve as a sustainable model and be implemented in other areas, providing extensive benefits to the environment and the local economy. Furthermore, this activity introduced the concept of sustainable waste management to the community, providing them not only with new knowledge about organic waste processing but also with the opportunity to apply these techniques in their daily lives.

Environmental management auditing is a strategic tool used to assess an organization’s performance in environmental management. Its main objectives are to enhance compliance with regulations, identify environmental risks, and strengthen corporate social responsibility. This study uses a bibliometric approach to analyze trends and research opportunities in the field of environmental management auditing during the period 2015–2025. Utilizing the Publish or Perish and VOSviewer software, this study examines 200 publications obtained through Google Scholar, revealing citation patterns, author collaborations, and frequently occurring keywords in the literature. The analysis results show that topics such as auditing, disclosure, governance, and big data dominate the existing literature, reflecting significant attention to transparency and data management in environmental audits. Additionally, there is a noticeable shift toward the use of technology in environmental auditing practices, including the use of big data and analytics to support audit processes. Bibliometric visualization also identified several areas with low density, such as implementation and environmental information, indicating potential research opportunities. This suggests that although significant research has been conducted, there is still room for further development, particularly regarding the implementation of environmental management audits across various industries. This study provides valuable insights into the development of more adaptive, multidisciplinary environmental auditing strategies that align with sustainable development goals.

This study aims to analyze the structure and composition of vegetation on the banks of the Ira River (Wae Ira), Negeri Kamarian, Kairatu District, West Seram Regency. Riparian vegetation plays an important role in maintaining the stability of river ecosystems, both in terms of ecological, hydrological, and biodiversity aspects. The method used in this study is a combination of the continuous strip sampling method and the line plot sampling method, which are applied to four levels of vegetation growth, namely seedlings, saplings, poles, and trees. The results of the analysis show that the vegetation structure in the study area is divided into four strata, with varying species compositions in each stratum. The dominant species found include Pulai (Alstonia scholaris), Pulaka (Cyrtosperma merkusii), Buah rao (Dracontomelon mangiferum), and Salam (Syzygium polyanthum). The highest Importance Value Index (INP) at the tree level is owned by Pulai (Alstonia scholaris) at 54,2. The highest vegetation density is at the seedling level with 52000 individuals/ha and the lowest at the tree level with 341 individuals/ha. The Shannon-Wiener diversity index (H') ranges from 1.87–2.65, indicating a moderate level of diversity. The results of this study indicate that the Ira River border area still has a relatively good vegetation structure and composition, although there are ecological pressures that cause dominance by certain species

Lead apron is a type of personal protective equipment in the form of an apron and made of lead which is designed to protect the body from the dangers of radiation. Menurut Keputusan Menteri Kesehatan Republik Indonesia Nomor 1250/MENKES/SK/XII/2009 regarding Quality Control Guidelines to protect the density and physical condition of the lead apron, testing is required once a year and may be carried out before one year if necessary. To maintain the quality of the lead apron, it needs to be stored in a good manner and avoid stacking and folding it. Because it can cause damage which will reduce its function as radiation protection equipment. Lead apron storage should be stored flat without folds or on a special shelf. The aim of this research is to test lead aprons in the Radiology Installation of Regional Hospitals Mangusada Badung to determine the feasibility of the lead apron. The type of research used is descriptive quantitative research with a survey approach, observation, namely by carrying out testing, measurement and documentation. This research was conducted in July. The results of this study indicate that lead apron testing in the Radiology Installation of Regional Hospitals Mangusada Badung What has been done is that the four lead aprons are still in good condition and still suitable for use.

Dengue Hemorrhagic Fever (DHF) is an infectious disease caused by the dengue virus and transmitted through the bite of the Aedes aegypti mosquito. The high risk of dengue transmission is greatly influenced by the density of mosquito larvae which correlates with environmental conditions and community behavior. This study aims to describe the density level of Aedes aegypti mosquito larvae in the working area of the Gandus Health Center in Palembang City in 2025 through the measurement of House Index (HI), Container Index (CI), Breteau Index (BI), Larvae-Free Numbers (ABJ), and Density Figure (DF). The method used was descriptive observational with a purposive proportional random sampling technique on 100 households in three RTs. Data was collected through direct observation using checklist sheets. The results showed that the HI was 66%, CI was 44%, BI was 107%, and ABJ was only 34%, which indicates that the larval density is very high and far below the WHO standard (≥ 95%). The DF value is in the range of 7–9, reinforcing the finding of high vector density. This condition shows that the area is at high risk of dengue transmission. Interventions are needed in the form of regular mosquito nest eradication (PSN), increasing public education, and strengthening the role of jumantic cadres in sustainable vector control.

Weather and cloud cover are two fundamental atmospheric elements that are closely interconnected and play a vital role in understanding, classifying, and predicting atmospheric conditions. Accurate classification of weather conditions is essential not only for meteorological studies but also for practical applications in agriculture, aviation, transportation, and disaster management. Among the various statistical techniques available, correspondence analysis has proven to be an effective exploratory method for revealing associations among categorical variables by displaying their relationships in a two-dimensional graphical map. The primary objective of this study is to examine the relationship between different categories of weather conditions and levels of cloud cover using correspondence analysis. The data were sourced from the Kaggle platform, consisting of 13,200 observations with two key categorical variables: weather conditions (sunny, cloudy, rainy, and snowy) and cloud cover (clear, partly cloudy, cloudy, and overcast). This large dataset provides sufficient variability and reliability to capture the complex interdependence between the two variables. The findings reveal a statistically significant relationship between weather categories and cloud cover levels. The correspondence map visualization shows distinct patterns: clear weather is strongly associated with cloudless skies, while rainy and snowy weather conditions are predominantly linked to fully overcast skies. Cloudy and partly cloudy conditions occupy an intermediate position on the correspondence map, reflecting a transitional state between favorable and unfavorable weather. The first dimension of the map represents a spectrum from favorable weather conditions (sunny and clear) to adverse conditions (rainy and snowy), whereas the second dimension primarily reflects the intensity or density of cloud cover, ranging from thin to thick cloud layers. Overall, this study demonstrates the usefulness of correspondence analysis as an exploratory tool for meteorological data, offering valuable insights into the interrelation of weather and cloud cover categories.

Dyslipidemia is a health problem characterized by impaired fat metabolism in the body, characterized by changes in blood lipid levels, either increasing or decreasing. This condition is generally seen through increased levels of total cholesterol, low-density lipoprotein (LDL), triglycerides, and decreased levels of high-density lipoprotein (HDL). This imbalance in the lipid profile, if persisted over the long term, has the potential to accelerate the formation of atherosclerotic plaque on artery walls, which can lead to cardiovascular disease. This study aims to determine the effectiveness of papaya leaf (Carica papaya L.) ethanol extract microcapsules in reducing cholesterol levels in white rats induced by a high-fat diet. The high-fat diet is formulated from a mixture of beef fat, eggs, and lard to increase cholesterol levels in a controlled manner. After the induction phase, the rats were divided into six treatment groups: a negative control group, a positive control group (simvastatin 0.36 mg), and three treatment groups with doses of papaya leaf ethanol extract microcapsules of 0.25%, 0.50%, and 0.75%. The treatment was given orally for 14 consecutive days. Total cholesterol levels were measured before and after treatment to evaluate the effectiveness of the intervention. The results showed that administration of papaya leaf extract microcapsules significantly reduced cholesterol levels. The 0.50% dose provided the most optimal effect, with a reduction reaching 77 mg/dL, greater than the simvastatin group. However, increasing the dose to 0.75% did not show a significant additional reduction effect, indicating an optimal dose-response point. Therefore, the 0.50% concentration can be considered the most effective dose and has the potential to be developed as an alternative natural cholesterol-lowering therapy. These findings also strengthen the potential use of papaya leaves as a bioactive source to support efforts to prevent and control dyslipidemia.