Applied Research in Science and Technology

Kinematic Analysis of Wrist and Elbow Angles in Badminton Serve Techniques Based on IMU Sensors

2025-05-05T13:44:46+07:00

Background: Motion capture technology is essential in sports biomechanics for analyzing human movement. Inertial Measurement Unit (IMU) sensors offer a practical alternative to camera-based systems, providing real-time motion analysis. While previous studies in badminton biomechanics have largely focused on stroke phases or lower-limb movements using optical systems, few have investigated the detailed angular behavior of upper-limb joint-particularly the wrist and forearm during specific serve types. Moreover, existing research rarely compares different serve techniques in terms of kinematics using wearable IMU-based methods.
Aims: This study aims to analyze angular movement patterns of the wrist and forearm during different badminton serve techniques using IMU sensor. Understanding the wrist and forearm movements is crucial, as they directly affect shuttle control, serve conssitency, and injury risk- especiaally in high-spedd, repetitive motions like the badminton serve.
Methods: Sensors were placed on the dorsum of the hand and the forearm near elbow to measure angular motion in three serves: backhand, short forehand, and long forehand.
Result: Results indicate that the centroid calculation results showed that each type of serves had a different angular distribution pattern, with varying contributions from the forearm and wrist. The forearm plays a dominant role in generating power, while the wrist contributes more to directional control and stabilization. Results indicate that forearm movement is more dominant in forehand serves, while wrist movement is more pronounced in backhand serves. These findings suggest that IMU-based motion analysis can optimize badminton techniques, prevent injuries, and enhance training programs.

Effects of Soaking Duration and Red Onion Extract Concentration on Celery Seed Germination

2025-05-20T11:38:16+07:00

Background: Celery (Apium graveolens) is a horticultural crop with significant economic and culinary value, particularly in Indonesia, where leaf celery is more commonly cultivated. Despite growing interest in hydroponic farming in regions such as Bangka Belitung, celery cultivation remains limited due to challenges in seed germination, especially under lowland and hot climate conditions. Celery seeds are known for slow and inconsistent germination due to hard seed coats and naturally occurring germination inhibitors like coumarin. Seed soaking in plant growth regulators (PGRs), including natural alternatives such as red onion (Allium cepa L) extract—rich in gibberellins and auxins—has been proposed to enhance germination and seedling vigor.
Aims & Methods: This study aimed to investigate the effects of different soaking durations (24 and 48 hours) and concentrations (0%, 10%, 20%, and 30%) of red onion extract on the germination performance of celery seeds.
Result: The results of this study indicate that a 24-hour soaking duration is the most effective in enhancing celery seed germination as under these conditions, the seeds experience only brief exposure to low oxygen levels. However, soaking seeds in red onion extract at concentrations of 10% to 30% resulted in lower germination parameters compared to the 0% because the concentration is suspected to be too high for celery seeds. Analysis of the interaction between soaking duration and extract concentration revealed that control seeds (without soaking or directly sowing) achieved germination performance comparable to the best treatment combination in terms of germination power, germination speed index, and mean germination time. At the same time, the highest vigor index and seedling length were observed in seeds treated with 10% red onion extract for 24 hours, which also showed similar performance to the control treatment.

Effect of Arbuscular Mycorrhyzal Fungi in Improving Soybean Growth in Ultisol Soil

2025-05-26T20:42:48+07:00

Background: Soybean is one of the most popular agricultural commodities in Indonesia, but its production is still low. Thus, it is necessary to make efforts to expand its agriculture in the form of marginal land development.
Aims: This study aims to examine the effect and obtain the best treatment dose of arbuscular mycorrhizal fungi (AMF) in ultisol soil to increase the growth of soybean plants (Glycine max (L.) Merill).
Methods: This experimental study employed a complete randomized design (CRD) with the treatment of arbuscular mycorrhizal fungi (AMF). The AMF treatment comprised five levels: no AMF, 4 g/polibag, 8 g/polibag, 12 g/polibag and 16 g/polibag. Each treatment was repeated four times, resulting in 20 experimental units and each experimental unit comprised three polybags so that this study used 60 polybags. The data were analyzed using Analysis of Variance (ANOVA) and continued with Duncan's New Multiple Range Test (DNMRT) at the 5% level.
Result: AMF treatment is able to increase the growth of soybean plants in the parameters of plant height, number of productive branches, flowering age, number of flowers, and harvest age. The AMF treatment dose of 12 g/polybag is proven to give the best results in increasing the growth of soybean plants. The use of AMF can be an effective strategy in optimizing soybean production, especially on marginal lands.

Development and Implementation of WhatsApp-based Health Literacy Media for Pregnant Women (Rakes Bumil): A Community Empowerment Approach using ADDIE and AIDA Models

2025-06-11T13:54:00+07:00

Background: Pregnant women in urban areas are used to accessing digital information, but not all of it is easy to understand, especially for those with low health literacy. A survey in Bogor District showed that 27.5% of pregnant women have problematic literacy. WhatsApp, as a commonly used platform, has the potential to be an interactive educational media. Using the ADDIE stages and the AIDA strategy, the media was designed to deliver clear and engaging messages.
Aims: This study aims to develop and implement WhatsApp-based Rakes Bumil educational media with ADDIE stages and AIDA strategies to deliver accurate and interesting health information, to encourage an increase in the health literacy of pregnant women, especially in the aspects of knowledge, search, assessment, and decision making related to pregnancy health information.
Methods: This study uses a quantitative approach with participatory action research design for content validation and development, implementation of Rakes Bumil educational media following the ADDIE model and AIDA strategy.
Result: The media was developed through ADDIE stages, in Rakes Bumil there are ChatBot media, flyers, animated videos, and interactive quizzes. The feasibility test results show that the media is well received by pregnant women, with >90% of pregnant women stating that the media is feasible to use to support pregnancy literacy. The 14-day implementation showed an increase in engagement and understanding of health information. These findings form the initial basis for further research that will quantitatively evaluate the effectiveness of the media.

The Effect of Coal and Biomass on the Generation of Fly Ash and Bottom Ash at the Coal-Fired Power Plant Asam Asam Unit 1-4, South Kalimantan

2025-05-22T11:19:15+07:00

Background: One of the main environmental challenges in Coal-Fired Power Plant (CFPP) operations is the large amount of Fly Ash and Bottom Ash (FABA) produced, which creates significant waste management issues. Reducing FABA production through biomass co-firing has become a potential solution, yet its effectiveness in actual operations remains underexplored. Asam Asam Power Plant Unit 1–4, with a capacity of 4 × 65 MW in South Kalimantan, is one of the power plants that utilize sawdust biomass in its operations.
Aims: This study aims to analyze the effect of coal and biomass consumption on FABA generation during 2022, 2023, and 2024.
Methods: The method employed is multiple linear regression using Minitab version 21.4.1 software, with coal consumption (X1) and biomass consumption (X2) as independent variables and FABA generation (Y) as the dependent variable.
Result: The results show that coal consumption has a positive relationship with FABA generation, while biomass consumption shows a negative relationship. ANOVA test results indicate that only coal consumption significantly affects FABA generation. A notable decrease in FABA production in 2024 signifies an increase in biomass utilization in the fuel mixture, highlighting its potential in reducing solid waste generation from CFPP operations. A simulation involving three biomass-coal blending scenarios demonstrated that incorporating 20% biomass into the fuel mix can reduce FABA generation by up to 27.79%.

Projection of Climate Impact on Discharge and Energy Production of Cascade Hydroelectric Power Plant in North Sulawesi

2025-06-23T10:03:12+07:00

Background: Climate change is a major challenge for the sustainability of hydropower plants (PLTA) in tropical areas such as North Sulawesi, which are highly dependent on water availability from seasonal rainfall.
Aims & Methods: This study aims to project the water discharge and electricity production of the Tonsealama, Tanggari I, and Tanggari II hydropower plants based on the SSP2-4.5 and SSP5-8.5 climate change scenarios. Historical climate data (2014–2024) from BMKG and hydropower plant operation data (2019–2024) are used to train the prediction model using the Random Forest algorithm, with bias correction performed on the CMIP6 GCM output through a hybrid approach combining Random Forest and Delta Change.
Result: The results show a consistent decrease in discharge and energy at the three hydropower plants, especially in May, which has been the peak of the rainy season. The average annual discharge decrease reached 9%, while the decrease in electricity was recorded at 5,528.77 MWh (SSP2-4.5) and 3,053.42 MWh (SSP5-8.5) for the Tonsealama hydropower plant; 8,085.37 MWh and 12,625.98 MWh for PLTA Tanggari I; and the highest decline was experienced by PLTA Tanggari II of 18,160.42 MWh and 9,255.40 MWh. Although higher warming occurs in the SSP5-8.5 scenario, occasional extreme rainfall events partially offset the decline in energy production. These findings emphasize the importance of adaptation strategies through more flexible reservoir management, turbine operations, and integrated water resource planning to increase system resilience to future climate uncertainty.

Waste Power Plant as an Innovative Solution to Overcome Air Pollution in Bantargebang Integrated Waste Management Facility

2025-05-18T16:22:53+07:00

Background: The dominance of domestic waste in Bantargebang Integrated Waste Management Facility (IWMF), makes the characteristics of the waste can be categorized as combustible waste, with the type of waste mostly plastic and non-plastic. Waste dumped in Bantargebang creates new problems related to environmental pollution. The Merah Putih Waste Power Plant (Pembangkit Listrik Tenaga Sampah = PLTSa) is an important thing in efforts to control air pollution and waste management, where the quantity of waste production is relatively large and needs to be handled immediately.
Aims: This study aims to analyze the benefits of the Waste Power Plant in reducing air pollution at the Bantargebang IWMF.
Methods: The research uses a descriptive approach to systematically describe, analyze, and explain phenomena. In addition, quantitative analysis is applied to process and interpret data in the form of numbers. Data collection methods include air pollution data analysis, where air quality monitoring data was collected between 2019 and 2024 after the PLTSa began operating.
Result: Based on the data obtained, the air quality in 2019 before the PLTSa operated and after the PLTSa operated in 2024, it can be seen that the concentration of PM2.5 decreased to 33.8 µg/m³, SO2 decreased to 2.1 µg/m³, CO decreased to 1,437.0 µg/m³, NO2 decreased to 0.5 µg/m³. Furthermore, it can be seen that after the PLTSa Merah Putih Bantargebang began operating in mid-2019, it showed benefits in 2024, where most air pollutants decreased compared to 2019 (before operated), such as PM2.5, SO₂, CO, and NO₂. This decrease reflects the success of the emission control system from the waste combustion process applied to the PLTSa.

The Effectiveness of Adding Immunostimulants, Probiotics, and Liming Methods on Water Quality and Productivity of Shrimp Litopenaeus vannamei in Dewi Laut Aquaculture Company, Garut, Indonesia

2025-06-14T18:36:15+07:00

Background: The whitelegs shrimp Litopenaeus vannamei is one of Indonesia's leading commodities. However, Intensive culture of Litopenaeus vannamei faces challenges such as environmental stress and decreased productivity due to fluctuating water quality.
Aims & Methods: This study aimed to evaluate the effectiveness of adding immunostimulants (vitamin-mineral mix and garlic extract at 2 ppm), probiotics (2 ppm every two weeks), and lime treatment (CaO at 10 ppm) on water quality and the productivity of L. vannamei in ponds at PT. Dewi Laut Aquaculture, Garut. The observed productivity parameters included Average Body Weight (ABW), population, biomass, Feed Conversion Ratio (FCR), Survival Rate (SR), and size. Meanwhile, the measured water quality parameters included physical parameter such as temperature, chemical parameters such as pH, dissolved oxygen (DO), total ammonia nitrogen (TAN), total alkalinity, and total organic matter (TOM), as well as biological parameters such as total phytoplankton, total bacteria count (TBC), and total vibrio count (TVC).
Result: The results showed that the applied treatments produced good culture performance, with ABW reaching 13.37 grams, SR at 91.01%, FCR at 1.7 and productivity of 20.39 tons/ha. Meanwhile, water quality monitoring indicated that some parameters exceeded the ideal ranges for shrimp culture, such as pH (maximum 9.12), TOM (up to 134 ppm), and TAN (up to 2.6 ppm). However, there is synergy between probiotics and immunostimulants, these conditions were still tolerable for the shrimp.

Using SoilGrids250m for Overlooking Spatial and Vertical Distribution of Soil Physico-chemical Properties Over Tropical Climate Asia

2025-06-13T21:06:10+07:00

Background: Understanding the interaction, spatial and vertical distribution of soil chemical properties over climate type in tropical Asia and various depths of soil is essential for sustainable land management, particularly in regions experiencing dynamic conditions.
Aims & Methods: This study investigates the relationships of each parameter such as cation exchange capacity (CEC), soil pH, and soil organic carbon (SOC) tropical Climate Asia. Using stratified random sampling based on Köppen–Geiger climate classifications and a consistent spatial resolution of 0.25° × 0.25°, we analyzed 45 sample points distributed across tropical rainforest, monsoon, and savanna climates. The data were extracted from SoilGrids 250m and reconciled using conservative remapping and bilinear interpolation techniques. Corresponding soil chemical data were obtained from validated regional databases.
Result: The results show that a correlation matrix analyzing relationships among key soil physico-chemical properties across multiple depths. Strong positive correlations were found between soil organic carbon (SOC) and total nitrogen (N) (r > 0.8), reflecting their shared origin in organic matter. Bulk density (BD) exhibited moderate to strong negative correlations with SOC and N (r ≈ -0.5 to -0.8), particularly in surface layers, indicating the influence of organic matter on soil structure. Correlations weaken with depth, reflecting reduced nutrient interaction. These patterns highlight the importance of organic matter inputs and minimal soil disturbance in maintaining soil health and guiding sustainable land management strategies.

Application of Biosecurity Strategies for the Control of MAS (Motile Aeromonas Septicemia) in Tubifex Worms (Tubifex sp.) for Larval Catfish (Pangasius sp.) Culture

2025-06-05T12:20:36+07:00

Background: Catfish (Pangasius sp.) is one of the high-value freshwater aquaculture commodities in Indonesia. To ensure sustainable production, hatchery management plays a crucial role, as the larval and juvenile stages are the most vulnerable to environmental stress and disease outbreaks. During the larval phase (7–14 days post-hatch), Tubifex worms (Tubifex sp.) are commonly used as a natural feed due to their high nutritional content and digestibility.
Aims & Methods: This study aimed to evaluate the effectiveness of formalin in suppressing Aeromonas hydrophila in Tubifex worms (Tubifex sp.), which are used as natural feed for larval catfish (Pangasius sp.). The research was conducted in two phases: in vitro and in vivo assays. The in vitro assay was carried out to determine the minimum inhibitory concentration (MIC) and inhibition zone of formalin against A. hydrophila. The in vivo assay consisted of two parts: a toxicity test of formalin on Tubifex worms and an evaluation of the effect of treated worms as feed on the survival of catfish larvae. A completely randomized design (RAL) was employed, consisting of four treatments with three replicates each: K (control—untreated Tubifex), A (400 ppm formalin immersion without rinsing), B (400 ppm formalin immersion with one rinse), and C (400 ppm formalin immersion with two rinses).
Result: The results demonstrated that a 400 ppm formalin concentration effectively inhibited the growth of A. hydrophila. Treatment C (two rinses following immersion in 400 ppm formalin) significantly reduced the toxic effects of formalin on the Tubifex worms used as natural feed. Consequently, this treatment led to an improvement in the survival rate of catfish larvae, reaching 44.6 ± 11.5% over a 14-day rearing period.