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Sensitivity of WRF-HAILCAST Model for Hailstone Detection in Central Lombok on 24 February 2019
Get PDFHail is one type of extreme weather produced by Cumulonimbus clouds or convective clouds. Due to deep convection involve to physical processes and cloud dynamics, hail may occur in Indonesia. WRF-HAILCAST was used in this study to detect hailstone. The HAILCAST model is applied to WRF-ARW version 4.0 and above in WRF-HAILCAST. The purpose of this study was to determine the sensitivity of the WRF-HAILCAST model with a modified WSM6 microphysics scheme to detect hailstones that possible to reach the surface. The maximum reflectivity value, vertical reflectivity, maximum hailstone diameter, and cloud microphysics were all approximated properly as a result of this study. The estimation of maximum diameter hailstone was 1.6 cm at the time of hail occurred, and the graupel mixing ratio showed 2.2 g/kg which represented small hail could be detected in this model. However, WRF-HAILCAST tends to underestimate and has not been able to estimate the time of hail events according to weather radar properly
Study Of Fishing Vessel Motion Response At Muara Angke Port
Get PDFMuara Angke Port, one of Indonesia's busiest fishing hubs, faces significant challenges due to dynamic water conditions and heavy vessel traffic, including waves, currents, tides, and vessel interactions. These conditions impact the motion response of fishing vessels, affecting their stability, maneuverability, and operational safety. This study aims to analyze the motion response of fishing vessels operating, focusing on environmental factors influencing vessel operations. A comprehensive analytical approach is employed, including the panel method for seakeeping analysis. Specific seakeeping criteria for fishing vessels, as proposed by Tello, are applied to assess vessel performance in various sea states. The findings indicate that fishing vessels can operate effectively in sea states with wave heights up to 3 meters, or sea state 5 and below. These results provide valuable insights into how fishing vessels respond to environmental challenges at Muara Angke Port, offering recommendations for improvements in vessel design. The study emphasizes the importance of developing operational strategies to reduce accidents and enhance the sustainability of the fishing sector, while supporting the long-term resilience of Indonesia's fisheries industr
Failure Mode and Effect Analysis (FMEA) for Periodic Maintenance Tasks of Medium Voltage Switchgear 20 kV
Get PDFMedium voltage (MV) switchgear at 20 kV, known as Panel Hubung Bagi (PHB) 20 kV in Indonesia, is a critical component of the electrical power distribution system, containing fuses, switches, and power conductors. A failure in this switchgear could lead to system-wide malfunctions, with potential catastrophic consequences such as fires or explosions. To prevent such events, it is essential to perform regular and well-planned maintenance. This research aims to optimize the maintenance process for MV switchgear, focusing on reducing maintenance tasks and frequency without compromising system reliability. The study employs the Failure Mode and Effect Analysis (FMEA) methodology, refined to reduce unnecessary maintenance actions. A Systematic Literature Review (SLR) was also conducted to analyze previous research on FMEA applications in 20 kV MV switchgear maintenance. Traditionally, maintenance was guided by manufacturers' recommendations, experience, and technical judgment, resulting in 3554 man-hours (MH) of labor every two years. However, by applying the refined FMEA process, maintenance requirements were significantly reduced to just 212 MH over the same period. This reduction represents a cost saving of 1678%, while still ensuring that the reliability of the MV switchgear at 20 kV is maintained at a high level. These findings underscore the importance of adopting systematic maintenance approaches to improve operational efficiency and reduce costs in power distribution systems
Analisis Furosemid Injeksi 10 mg/mL Dalam Validasi Proses Furosemid Injeksi 10 mg/mL Secara Spektofotometri UV-Vis
Get PDFFurosemide is a diuretic derivative of anthranilic acid. The diuretic activity of furosemide is mainly by inhibiting the absorption of sodium and chloride. This study aims to validate the production process of 10mg/mL injection furosemide; therefore, it can be known whether the production process has run well and product is suitable for consumption. There are eight parameters in this study including the determination of furosemide concentration in the sample, the results obtained that the concentration is 102.14% which is a qualified number. Furthermore, the analysis of the uniformity of the final mass concentration, with the difference in concentrations obtained meets the requirements, the RSD value is 1.64. This indicates that the mixing process has run well, accordingly it is able to produce a homogeneous product. Furthermore, the determination of volume uniformity, sterility, endotoxins, bioburden, pH and particulates also provides qualified results, hence the production process of the three batches analyzed runs well so as to produce qualified and consistent products
Gulf of Lampung Bamboo Fixed Net Cages Structural Design Identification
Get PDFRenewable materials are being discussed and researched more recently. One renewable source of material is plants, either with a long life like wood or a short life like bamboo. In Indonesia, bamboo is widely used also for the structures of fixed net cages. This research aims to analyze the structure of the fixed bamboo net cage installed in the waters of Gulf Lampung. The analysis used in this paper is in place. The in-place analysis will give the unity check and deflection result due to load combined by the standard BKI Guidelines for Aquaculture. Based on the results, the structure has met the standard in operation conditions with the maximum unity check value of 0.52 on the group pile. Nevertheless, the largest unity check value of 1.20 on group piles in storm conditions is due to increased lateral loading. The result of deflection already has good serviceability, with a maximum horizontal deflection value occurring in storm conditions of 0.58 cm and a maximum vertical deflection in operation conditions of 0.89 cm. The structure of the fixed net cages has yet to meet the requirements during storm conditions by unity check
Pipeline End Manifold (PLEM) Structural Response Analysis due to the Settlement Process
Get PDFPipeline End Manifold (PLEM) is an offshore structure that consists of a simple subsea manifold that combines two or more pipelines into one pipeline. Like other offshore structures, the risk of seabed settlement may occur, and settlement is predicted can increase the stress of pipe and frame members. Stress that exceeds the allowable stress of codes may be a danger. So, stress analysis of the UC ratio of pipe and frame PLEM due to the settlement must be done. Stress analysis is performed using the numerical method with the model in FEM software. UC ratio refers to AMSE B31.8 2010 for pipe and API RP 2A (WSD) 22ed 2014 for the structural frame. From this analysis, the allowable settlement of pipe codes is at a depth below 450.42 mm. The deeper the settlement, the more stress the member frame increases. At a depth of 600 mm settlement, the greatest stress, 133.125 N/mm^2, UC 0.375, is found on member E04(L). According to the pipe codes, the maximum slope is 2.27˚ on the southward slope. The biggest effect of tilt settlement on the member frame is found in the west direction at member E04(U) with a value of 244.6 N/mm^2, UC 0.689, tilt settlement 3˚
Studi Komparasi Penggunaan Base Isolation Tipe Lead Rubber Bearing dan Friction Pendulum Bearing pada Bangunan Gedung Anutapura Medical Center Palu
Get PDFEarthquake-resistant-building with seismic isolation system is the concept that separate upper building from the source of vibrations on subgrade. Because it's separated, the height of the building is limited to avoid rollout. AMC building is located in Palu City, an earthquake-prone area, so it’s necessary to plan isolation system to reduce the earthquake load and minimalize damage. This study used ETABS program to model structure with fixed-base, LRB and FPB. They are analyzed by pushover and nonlinear time history analyses. The results show that the performance level of fixed-base structure is LS while performance level of LRB and FPB types are IO. The LRB type structure increases the structure period by 129.6%, while the FPB type increases by 160.3% compared to the fixed-base type. The LRB type reduces the roof maximum-drift by 65.6%, while the FPB type reduces by 68.8% compared to the fixed-base roof maximum-drift
Analisis Pengaruh Faktor Environmental, Social, And Governance Terhadap Foreign Direct Investment di Negara ASEAN
Get PDFParadigma pembangunan berkualitas menjadi langkah prioritas dan fokus global saat ini untuk mencapai Sustainable Development Goals (SDGs). Akan tetapi, banyak negara masih terjebak dalam pola pembangunan semu yang berakibat deforestasi, polusi udara, dan penurunan kualitas air. Di sisi lain, Foreign Direct Investment (FDI) sebagai salah satu sumber pendanaan negara mengalami pergeseran tren menjadi investasi berkelanjutan yang mempertimbangkan aspek Environmental, Social, and Governance (ESG). Penelitian ini bertujuan menganalisis faktor-faktor ESG yang berpengaruh terhadap FDI. Metode yang digunakan adalah pendekatan kuantitatif dengan teknik analisis regresi data panel. Sampel penelitian ini sebanyak 10 negara ASEAN dari tahun 2010 hingga 2021. Hasil analisis menunjukkan bahwa variabel Environmental (E), Social (S), and Governance (G) menunjukkan pengaruh negatif signifikan terhadap FDI. Penelitian ini memberi rekomendasi pada pemerintah untuk merumuskan strategi investasi yang mendorong implementasi ESG dalam mempromosikan pembangunan berkualitas dan berkelanjutan di ASEAN
Investigating the Impact of Plain Flap as Lift Enhancement on Symmetrical Airfoils
Get PDFSymmetric airfoils like NACA 0015 have limitations in generating lift compared to asymmetric airfoils. Therefore, additional devices are needed to overcome this limitation. This research analyzes the use of a lift enhancement device called a plain flap, which is installed on the trailing edge of the NACA 0015 airfoil using the CFD method. Simulations were conducted at a Reynolds number of using the k-epsilon turbulent model. Three variations of geometry models were simulated: the NACA 0015 airfoil without a flap, the NACA 0015 airfoil with a plain flap at a deflection angle of 15°, and the NACA 0015 airfoil with a plain flap at a deflection angle of 30°. The simulation results show that the use of a flap can increase the maximum lift coefficient (Cl) of the airfoil. Initially, the maximum lift coefficient was 1.15 at an angle of attack (AoA) of 15°. With a plain flap deflection angle of 15°, the maximum lift coefficient increased to 1.5 at an AoA of 13°. With a plain flap deflection angle of 30°, the maximum lift coefficient further increased to 1.71 at an AoA of 10°. However, the use of a plain flap also leads to a significant increase in drag. On average, the drag coefficient (Cd) increased by 65% with a plain flap deflection angle of 15° and by 178% with a plain flap deflection angle of 30°
Charging and Discharging Process Analysis of Energy Management System Strategy Towards Battery Aging in Series Configuration Hybrid Vehicle
Get PDFBatteries, crucial for hybrid and electric vehicles, inevitably experience capacity loss over time due to regular usage, known as battery aging. The degradation is influenced by factors like the C-rate, depth of discharge (DOD), and temperature variations. This study delves into a hybrid series-configured vehicle that integrates both a battery and an engine-generator as primary energy sources. The primary objective revolves around determining an optimal energy management system (EMS) that mitigates battery aging effects. Testing was conducted across varying speeds: 17 km/hour, 30 km/hour, and 50 km/hour, involving two operational modes—full electric and hybrid. The engine-generator activation was contingent upon the battery's state of charge (SOC) set at 40% and 60%, operating consistently at 7000RPM and 7500 RPM. Data collected from these experiments facilitated the assessment of battery aging, simulated through MATLAB Simulink software. The findings highlighted that the most favorable battery aging occurred at 50 km/hour, when the engine-generator was engaged at 60% SOC and operated at an engine speed of 7500 RPM. Notably, the hybrid mode showcased superior battery longevity, particularly at higher speeds