Explore the vast range of titles available.

The flow that crosses the arrangement of four circular cylinders will form a certain flow pattern according to the geometry of the body contour, the distance between the cylinders, and the flow orientation (α), and generated aerodynamic forces, such as lift force, drag force, as well as induced vibration on the body. The force coefficients on four circular cylinders in an equispaced arrangement with a staggered configuration located near a plane wall were calculated through the pressure distributions measurement. The pressure distributions on each cylinder surface and the plane wall were measured for various gap ratio values of G/D= 0.0 and 0.2 (G, the gap between cylinder to the plane wall; D, diameter) and L/D= 2.7 (L, gap spacing between cylinders) in a uniform flow at a Reynolds Number of 1.743 x 10 4 . The results show that the drag and lift coefficients on the cylinders depend on the gap ratio value of G/D. The drag coefficient decreases, when the amount of G/D increases, especially on the upstream cylinders. The lift coefficient on the upper-downstream cylinders has a significant value more than other cylinders at a small spacing ratio.

This paper investigates numerically the effect of the circular cylinder's stagger angle variation installed in front of the returning blade on the performance of Savonius vertical axis water turbine. The numerical simulation uses Computational Fluid Dynamics using ANSYS 17.0 to solve the incompressible Unsteady Reynolds Averaged Navier-Stokes (URANS). Firstly, numerical model is verified by varying the grid size at TSR 1,078. Then numerical results are validated by existing experimental data, in this case the torque coefficients. The working fluid is in verification using air at Reynolds of 4.32 x105 and convert to water fluid. Ratio of circular cylinder diameter to the turbine diameter (ds/D) is 0.5 at gap (S/D) of 0.95 with varying TSR of 0.3, 0.5, 0.7, 0.9, 1.1 and 1.3 and stagger angle (α) of 0, 30, 60 and 90 degree. The results show that the maximum power coefficient increases about 29.84% at a TSR of 0.9 for stagger angle of 60 degree.

This work will investigate the effect of the circular cylinders distance variation perpendicular the free stream installed in front of the returning to increase the turbine performance. Computational Fluid Dynamics using Gambit 2.2.30 software and ANSYS 17.0 software has been used to solve the incompressible URANS. Numerical model is validated towards experimental data at TSR 1.078. The working fluid is in verification using air at Reynolds of 4.32 x10 5 . The ds/D is 0.5 at gap (S/D) of 0.95 with varying stagger angle of 0°, 30°, 60° and 90° with TSR of 0.3, 0.5, 0.7, 0.9, 1.1 and 1.3. The change of the stagger angle increase the turbine performance at a stagger angle of 60° followed by the increase of pressure in front side and reduce of the back of blade. In addition, stagger angle of 0° influences a circular cylinder become blockage and decrease the performance.

This study has been employed experimentally towards Savonius water turbine by using Myring equation for n=1. This work will be varied to overlap ratio of 0, 0.05, 0.1, 0.15, 0.2, 0.25 and 0.3. The overlap ratio of 0 can be called as the conventional turbine using half circle. The experiment is tested in flume tank by 1.1 m of wide and 0.8 m of height and the water velocity 0.22 m/s. The turbine have 0.4 m of height and 0.4 of diameter. This work will be calculated the torque coefficient and the power coefficient. The power coefficient is called the performance coefficient. The results indicated that the best performance coefficient has improved in about 62.83 % at overlap ratio of 0.2.

BACKGROUND AND OBJECTIVES: The Ministry of Marine Affairs and Fisheries of Indonesia has introduced its blue economy framework to promote sustainable use of marine and fishery resources while ensuring ecosystem protection. This study investigates five major programs initiated by the Ministry that concentrate on ecological sustainability and the effective use of Indonesia's marine biodiversity: expanding marine conservation areas, implementing a quotabased fisheries system, monitoring coastal and small island regions, advancing sustainable aquaculture, and addressing marine plastic pollution. This study focuses on the application of the Ministry's fisheries Blue Economy initiatives, seeking to establish future strategies derived from the experiences accumulated during two years of operation. METHODS: To assess the implementation of these key initiatives, participatory approaches, including focus group discussions, semi-structured interviews, and key informant interviews, were utilized to gather insights into program implementation experiences and lessons learned. In-person interviews were performed utilizing a blend of closed and open-ended questions. The focus was on key informants, which comprised representatives from four Directorate Generals, seven unit coordinators, non-governmental organization members, and participants from fishermen groups. Following a pre-test and subsequent revisions, the final questionnaire was finalized with 25 questions. These covered topics such as knowledge of the Ministry's five key initiatives, understanding of regulatory enforcement, perceptions of blue economy management, and suggestions for future strategies FINDINGS: The implementation of quota-based fisheries system, known as Penangkapan Ikan Terukur, has demonstrated significant progress, particularly in fisheries management area 718, where increased vessel landings have minimized the need for transporting catches back to Java. The expansion of marine conservation initiatives has led to the establishment of protected areas totaling 97.5 million hectares. Nevertheless, there are ongoing challenges in effectively linking these areas, largely attributed to their vast expanse and insufficient funding. Sustainable aquaculture has been prioritized, achieving a remarkable increase in shrimp farming productivity from 0.6 to 40 tons per hectare per cycle. In addition, the Maritime Intelligent Platform has refined the licensing procedures for marine and fishery activities, resulting in better compliance with regulations. The Ministry's public engagement campaign, \"Month of Loving the Sea,\" has mobilized 2,858 participants over two years, removing nearly 172 tons of plastic waste from the ocean. CONCLUSION: While challenges such as resource limitations and the need for advanced technology adoption persist, the blue economy initiatives exhibit strong potential for success. Regular monitoring and evaluation play a vital role in tackling these issues, thereby solidifying Indonesia's commitment to the sustainable management of marine resources and the blue economy principles.

BACKGROUND AND OBJECTIVES: Marine protected areas are critical tools for conserving biodiversity and sustaining ecosystem services. Nonetheless, their efficacy depends on the equilibrium between environmental conservation and the socio-economic advantages for coastal populations. The Savu Sea National Marine Park in Indonesia, the country’s largest marine protected area, encompasses vital ecosystems, while supporting local communities reliant on marine resources. The study objectives were to utilize the ocean health index plus framework to evaluate the health of Savu Sea National Marine Park, determine conservation priorities, and emphasize the potential for ocean health index plus to emphasize Indonesia’s Marine Protected Area network within the coral triangle. METHODS: A customized ocean health index framework was applied under two scenarios. Scenario 1 ten global ocean health index objectives utilizing a preservation-oriented weighting scheme that prioritizes preservation and emphasizes conservation outcomes. Scenario 2 concentrated on five primary ecological objectives that are most pertinent to the effectiveness of Marine Protected Areas. The indicators were obtained from satellite data, government reports, and expert judgment. The status scores were calculated relative to reference points, with future status determined by trend, pressure, and resilience componentsFINDINGS: The ocean health index plus score for Savu Sea National Marine Park was 69 under Scenario 1 and 87 under Scenario 2, indicating moderate to high ecological health. Ecological goals such as carbon storage (99), clean waters (96), and biodiversity (82) performed well, reflecting intact habitats and water quality. However, socio-economic goals such as artisanal fishing opportunity (30), natural products (24), and coastal livelihoods (33) showed weak performance. These circumstances underscore considerable socio-economic difficulties and reveal fundamental problems including restricted livelihood diversification, inadequate market access, and a declining fisheries value chain. The low scores for food provision (65) and livelihoods (34) suggest a direct link between the socio-economic deficits and the inability to harness the full potential of the marine resources. CONCLUSION: Savu Sea National Marine Park demonstrates strong ecological integrity but limited socio-economic benefits. Long-term management effectiveness requires integrating livelihood development, the enhancement of fisheries value chains, and the promotion of sustainable tourism in conjunction with conservation initiatives, ensuring that ecological achievements yield significant socio-economic advantages for the local communities.

Flood is the most frequent disaster in the world. The impact of floods is very large, like human and animal death, the villages vanished and other environments damaged. In disaster preparedness, it is very necessary to divide the stages of the disaster status level. Therefore the public can prepare themselves according to these stages. The stage of disaster preparedness status is also beneficial for the government and related institutions to act according to the status stage of the disaster. This paper will propose the early warning system for flood disaster based on fuzzy logic in IoT system. This algorithm was built 8 rules. The inputs are the rainfall and height of water. The output is the status of flood disaster. The types of disaster status are normal, moderate 1, moderate 2, emergency 1, and emergency 2. From the simulation result, it is concluded that this fuzzy logic model can to determine the status of flood disaster very well.

BACKGROUND AND OBJECTIVES: Pelagic fisheries play a vital role in sustaining coastal livelihoods and food security in the Eastern Indian Ocean, yet they also contribute to greenhouse gas emissions due to fuel-intensive operations. Notwithstanding their significance, there is a lack of empirical evidence concerning the carbon footprint associated with small-scale pelagic fisheries in Indonesia. The study aimed to quantify the carbon footprint associated with pelagic fisheries and to investigate variations related to fishing gear and target species, while examining temporal, seasonal, and catch per unit effort influences to enhance climate-resilient fisheries management in the Eastern Indian Ocean. METHODS: A five-year dataset from fuel records, logbooks, landings, and interviews was used to estimate carbon footprints using the Intergovernmental Panel on Climate Change Tier 1 method (2.68 kilograms carbon dioxide per litre diesel). Trends and relationships concerning gear-specific intensity and catch per unit effort were also analysed. FINDINGS: The average carbon footprints per vessel during 2019–2023 was 2.22 tons of carbon dioxide equivalent per ton fish. Monthly emissions ranged from 1.35 to 4.94 tons of carbon dioxide equivalent per ton fish, with levels 30 to 40 percent higher during peak fishing months (March–June), highlighting the strong influence of seasonal fishing intensity on emission variability. Longline fisheries exhibited the greatest carbon footprint, succeeded by gillnet and handline, while purse seine demonstrated the least cumulative emissions. Monthly catch per unit effort fluctuated from 0.56 to 2.52 ton per trip, demonstrating an inverse correlation that suggests greater stock abundance improves fuel efficiency per unit catch. At the species level, Yellowfin Tuna and Scad had the highest carbon footprint intensity, whereas Skipjack Tuna consistently showed the lowest emission levels.CONCLUSION: Although emission intensity remains moderate compared to industrial fleets, cumulative emissions from small-scale pelagic fisheries are significant and strongly effort driven. Re-revitalizing fish populations, boosting fuel efficiency, and embedding routine carbon accounting into fisheries governance are vital for ensuring that pelagic fisheries are in harmony with Indonesia’s sustainable and low-emission blue economy objectives.

This work has been done experimentally to the Savonius water current turbine by means of Myring equation for n =1. The myring for n=2 is called the conventional turbine with half circle or bucket. Experiment is tested in flume tank by 1.1 m of wide and 0.8 m of height. The free stream velocity is 0.22 m/s measured at 1.5 m from nozzle. The model is the Myring equation with n=1 by 0.4 m of height and 0.4 m of turbine diameter. The experimental study has investigated the torque coefficient and the power coefficient. The power coefficient has been called the performance coefficient. The experimental results shows that the Myring formula n = 1 have the performance coefficient higher than the conventional blade. The myring blade for n = 1 increases in about 42.88 % compared to the conventional blade.

BACKGROUND AND OBJECTIVES: The advancement of coastal fisheries can lead to improved livelihoods, yet it may also heighten fishing pressure and create hidden ecological risks, particularly in data-limited small-scale systems where ecological responses are not immediately detectable. The study objectives were to assess the trade-offs and synergies between economic development and ecological health in a small-scale coastal fisheries system under the Kampung Nelayan Merah Putih intervention in Samber–Binyeri Village, Biak Numfor, Indonesia.METHODS: An integrated framework combining the Ecosystem Approach to Fisheries Management, pressure-response analysis, field observations, interviews, secondary data, satellite-derived environmental indicators, and Generalized Additive Model analysis was applied to evaluate fisheries performance, fishing pressure, ecological conditions, and governance responses. To capture the environmental drivers impacting fisheries dynamics, oceanographic variability, such as sea surface temperature and chlorophyll-a, was taken into consideration.FINDINGS: The intervention improved economic performance, with fisher income increasing by 88.8 percent in peak seasons, production by 121.2 percent, and fishing trips by 44.4 percent. The overall Ecosystem Approach to Fisheries Management composite index reached 78 percent, indicating good sustainability performance. Economic, social, and fishing technology domains scored highly, while habitat and ecosystem conditions remained moderate at 60 percent. The mean catch per unit effort recorded was 42.78 kilograms per trip, which did not display a steady decline. Nevertheless, factors such as juvenile catch, habitat restrictions, and increased effort point to developing ecological pressure. These patterns suggest a potential hyperstability condition, where stable catch rates may not fully reflect changes in stock condition. Consequently, management should therefore focus on controlling efforts, restoring habitats, monitoring adaptive Ecosystem Approach to Fisheries Management monitoring, strengthening institutional coordination, and integrating local knowledge systems.CONCLUSION: Economic development in Samber–Binyeri has generated clear livelihood benefits, but stable catch per unit effort may mask underlying ecological risks caused by increasing fishing pressure. Indicators suggest the system is in a state of short-term ecological stability. To ensure long-term coastal fisheries sustainability amidst rising environmental variability and development, management must prioritize habitat restoration, adaptive strategies, and stronger institutional coordination.