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Rip Current Hazard in Klayar Beach, Pacitan, Indonesia: Inferred from Fluorescent Dye and UAV
Get PDFSouth coasts of Java have a unique landscape that exhibits exotic and phantastic natural view which is very attractive as tourist destinations. Indonesia has the world’s longest coastlines, the world’s highest coral diversity, and spectacular seascapes, therefore Indonesia’s coastal tourism potential is very promising. However, despite their attractiveness coastal water can be very dangerous to their visitors due to rip currents which isinhospitable to them. Klayar Beach (KB) is one of the most popular recreational beaches in Pacitan Regency, East Java Province, Indonesia. However, KB poses a hazard due to rip currents. This paper presents the result of field observations of rip currents utilizing fluorescent dying and unmanned aerial vehicle (UAV). We used UAV multirotor DJI Mavic 2 Zoom with video camera to take and monitor aerial photo and video of rip current flows. The result of this study proves that there is rip currents in KB. It also reveals that the maximum velocity reaches 0.8 m/s, with average width of 11 m, and total length 99.99 m. The type of rip current in the KB is structural boundary controlled and predicted as a permanent rip. Therefore, this evidence should be considered for promoting beach safety in this area
Performance Investigation of the Savonius Wind Turbine by Putting a Rotating Cylinder in the front of Advancing by Varying the Diameter and Stagger Angle
Get PDFThe wind energy is the one of the renewable energy to produce the power using turbine. The Savonius turbine have lower performance compared to the other. In this work, the method used is the experimental stu using the wind tunnel to flow air go to the Savonius turbine. The model used is a conventional Savonius wind turbine by adding cylinder installed in front of advancing area with a diameter of 0.4 m and a height of 0.4 m and ds/d of 0.1, 0.2, 0.3, and 0.4 with the rotation of 20 rpm at a stagger angle of 0°, 30°, 60°, and 90°. The experiment is kept constant at the velocity of 7 m/s. This work objective will determine the torque and power coefficient by varying the diameter and stagger angle. The results show that the biggest performance decreased was about 40% in the variation of ds/d of 0.3 with a stagger angle of 0°. The best results show that the wind turbine performance occurred the highest improvement in about 12% at the variation of ds/d = 0.4 with a stagger angle of 60°.
ECOTECT SIMULATION: ADVANCING ENVIRONMENTAL RESPONSIVENESS IN NATURE-BASED SCHOOL CONCEPTUAL DESIGN
Get PDFBalikpapan City focuses on the vision and mission of zero carbon emissions. One way to achieve this is to provide facilities with a sustainable natural school system with a green architectural approach. Students learn to care for ecosystems through hands-on, immersive experiences.This research aims to obtain an optimal building design in response to the local climate to create user comfort in learning activities. A learning building must support a learning objective focusing on acquiring specific skills, knowledge, or competencies in a particular subject. Geographically, the design location is in a wet tropical sub-climate, so the potential for sunlight can be utilized as an alternative source of renewable energy in buildings. This research uses Ecotect simulations during the design process to ensure the schools are sustainable and environmentally friendly with a focus on ecological aspects and building performance.This research uses quantitative methods to measure solar paths, radiation intensity, and shading indicators. The data collected guides the design process and creates energy-efficient and well-suited buildings to their environment. By integrating these insights from the beginning, nature-based schools in Balikpapan can become sustainability models, offering students an education deeply rooted in their natural surroundings. The results of this research are that the tropical climate at the design location can be used as an energy alternative in natural school buildings. However, the choice of building shape is a consideration in the design process because the shape of the building can influence the desired output
Macrobending Multimode Plastic Optical Fiber Coated with PANI-PVA composite as a pH sensor
Get PDFThe measurement of pH is very important in the medical, industrial and research worlds and each requires measuring instruments with different sensitivities.Measuring the pH of a solution in principle measures hydrogen ions in a solution.In this research, a pH sensor was designed and fabricated using multimode fiber optic macrobending with the fiber optic cladding being peeled off and replaced with a PAni-PVA (polyaniline-polyvinyl alcohol) composite layer.The bending diameter of plastic fiber optics is varied with sizes d = 2.5 cm, d = 2 cm, and d = 1.5 cm.The test results show that the pH sensor created is capable of measuring the pH of the solution linearly in the range pH = 2 to 10 <w:LsdException Locked="false" Pr
Feasibility of Utilizing Recycled Carbon and Polyester Composites for Ship Hull Construction: An Experimental Approach
Get PDFThe increasing environmental concerns surrounding fast fashion and the accumulation of waste materials have prompted a need for alternative, sustainable materials in various industries. This study aims to investigate the feasibility of utilizing recycled carbon and polyester composites for ship hull construction. An experimental approach is employed, focusing on tensile testing of material specimens, including carbon fiber and polyester, in accordance with ASTM D3039 standards. The method involves creating composite specimens, subjecting them to tensile tests, and analyzing the results through standard deviation to compare tensile strength and maximum load. The results demonstrate that the composites exhibit suitable mechanical properties for ship hull construction, with polyester showing an insignificant difference compared to carbon fiber composites. These findings provide a reference for future applications in shipbuilding, contributing to environmental sustainability efforts by repurposing waste materials
Optimizing Small Excavator Maintenance Activity Planning Using the Reliability-Centered Maintenance (RCM) Method II
Get PDFConstruction activities include the stages of construction, operation, maintenance, demolition, and rebuilding of a building. One of the construction activities in Indonesia is the construction of double-track railways. In the double-track railway construction project, there is a small excavator A which often fails. The excavator is used for excavation, land stripping, and embankment work. Failures that occur can disrupt construction implementation and can result in the company experiencing losses. Maintenance activities in the construction company that is the research location have a maintenance schedule, namely every 3 months and every 6 months based on the manual book, without adjusting the condition of the equipment. Therefore, it is necessary to analyze excavator components so that appropriate maintenance is known. RCM II is a maintenance evaluation method so that system components run well and according to the expected function by determining a maintenance action that must be carried out based on the characteristics of machine use so that maintenance activities run optimally. This research uses the RCM II method to determine the maintenance schedule, as well as the FMEA method. The FMEA results show 43 failure modes. RCM II decision worksheet analysis showed that 8 components had scheduled discard task maintenance, 3 components had scheduled restoration task maintenance, and 1 component had scheduled on-condition task maintenance
The Application of Grasshopper to Redesign Ship Hulls with a Parametric Approach Method Based on Delftship Reference
Get PDFMore than a year has passed since Francisco Pérez-Arribas (2023) introduced a parametric-based hull design method using Python scripts, beginning with the cross-sectional area (CSA) design. Several experimental studies have been carried out to improve the method and the quality of ship design. This study aims to generate an optimal hull design by utilizing normal vectors derived from the x and y vectors. These normal vectors are applied parametrically to determine the shape of the hull. The study also employs a cubic spline-based parametric technique for designing yacht hulls. The purpose of this study is to introduce the concept of parametric design through the development of visual programming used to form cross-sectional area curves and generate hull geometry. This study also discusses both the advantages and limitations of using visual programming approaches to accelerate the design process. By varying the CSA shape of the DelftShip model, the resulting parametric model has a high level of accuracy, with a difference of - 0.097016% in LCB and -0.28785% in volume when compared to the DelftShip model. results from Grasshopper reveal significant differences, particularly below a draft of 0.475, where the CP values from Grasshopper are lower than those from DelftShip. The parametric approach using normal vectors not only facilitates design exploration but also holds the potential to enhance overall hull design quality and optimization
The Determining Success of Polyculture Caulerpa sp and Litopenaeus vannamei using AHP Analysis
Get PDFThe Polyculture Caulerpa sp and Litopenaeus vannamei can reduce the risk of ecological impacts, increase shrimp growth, survival, production, increase shrimp resistance to disease, and maintain optimal water quality. Analytical Hierarchy Process (AHP) begins by determining the priority between water quality, growth rate, and harvest yields as more optimal parameters for the success of a polyculture. The measure of success is determined based on the results of expert assessments of polyculture and cultivation that produce more optimal water quality (temperature, pH, brightness, salinity, and dissolved oxygen), growth rates, and harvest yields. The results of the overall AHP analysis, which determined the success of Caulerpa sp and Litopenaeus vannamei polyculture based on expert assessments, showed a good level of consistency. The results show that water quality is a priority parameter in the success of Caulerpa sp and Litopenaeus vannamei polyculture with a weight of 0.597, followed by a growth rate of 0.297 and a harvest yield of 0.106. The analysis of priority water quality indicators for the success of polyculture is dissolved oxygen with a weight of 0.514, followed by pH of 0.246, salinity of 0.119, temperature of 0.079, and brightness of 0.042. Based on the results of experts of the combined weight comparison, polyculture is more optimal than cultivation, with a considerable comparison weight of 0.678 and 0.322, measuring the success of Caulerpa sp and Litopenaeus vannamei polyculture
Sebaran Perubahan Suhu Permukaan Sebelum Dan Setelah Pandemi Covid 19 Terhadap Fenomena Urban Heat Island Di Kabupaten Batang
Get PDFPengembangan suatu wilayah merupakan dampak dari pertumbuhan penduduk dan segala aktivitasnya. Pembangunan infrastruktur sebagai pendukung aktivitas manusia mulai dari kebutuhan primer hingga sekunder, tanpa disadari secara perlahan dapat meningkatkan suhu suatu wilayah. Urban Heat Island (UHI) merupakan fenomena dimana suatu kawasan dengan padat penduduk berikut aktivitasnya mempunyai suhu yang relatif lebih tinggi dibandingkan dengan wilayah sekitar yang secara tidak langsung dapat menimbulkan perubahan iklim. Penginderaan jauh adalah salah satu cara untuk mengamati perubahan suhu permukaan pada periode tertentu. Penelitian ini bertujuan untuk mengidentifikasi perubahan suhu permukaan sebelum dan sesudah pandemi Covid 19 dengan kebijakan Pemberlakuan Pembatasan Kegiatan Masyarakat (PPKM) di Kabupaten Batang. Memiliki perubahan suhu permukaan dari tahun 2016 hingga 2023 sebesar ±2°C. Penelitian ini membuktikan bahwa perubahan suhu permukaan tidak hanya terjadi di kota-kota metropolitan tetapi di kawasan perkotaan seperti Kecamatan Batang dan beberapa kecamatan lainya di wilayah persisir Kabupaten Batang semenjak 2 tahun terakhir
Hubungan Preferensi dan Kepuasan Penghuni Perumahan Informal di Kota Surabaya
Get PDFSeiring dengan pertumbuhan populasi perkotaan, kebutuhan akan hunian semakin meningkat, namun sering kali tidak diimbangi oleh penyediaan perumahan yang memadai. Hal ini menyebabkan munculnya permukiman informal, yang umumnya berkembang di luar regulasi formal dan memiliki kualitas infrastruktur dasar yang rendah. Kecamatan Gunung Anyar di Surabaya menjadi salah satu kawasan di mana permukiman informal berkembang pesat tanpa izin resmi, dengan kondisi infrastruktur dan lingkungan yang jauh dari ideal. Meskipun demikian, banyak penghuni yang memilih kawasan ini sebagai tempat tinggal karena faktor lokasi strategis dan aksesibilitas. Penelitian ini bertujuan untuk mengkaji hubungan antara preferensi penghuni terhadap hunian ideal dengan tingkat kepuasan mereka dalam kondisi permukiman informal di Kecamatan Gunung Anyar. Data diperoleh melalui survei terhadap 74 responden dengan skala Likert untuk menilai preferensi dan kepuasan, serta dianalisis menggunakan statistik deskriptif dan regresi linier sederhana. Hasil analisis menunjukkan bahwa preferensi penghuni terhadap kondisi ideal berhubungan positif dengan kepuasan, dengan koefisien determinasi sebesar 56,2%. Hal ini menunjukkan bahwa 56,2% variasi kepuasan penghuni dipengaruhi oleh preferensi mereka terhadap hunian ideal. Meskipun preferensi penghuni terhadap kualitas hunian cukup tinggi, masih banyak aspek penting, seperti infrastruktur dasar, yang belum terpenuhi sehingga kepuasan yang dirasakan masih terbatas. Temuan ini menggarisbawahi pentingnya perencanaan dan pengembangan perumahan informal yang lebih terarah untuk meningkatkan kualitas hidup penghuni