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Systematic Analysis of Potential Marine Renewable Energy for Coastal Ecological Balance on Bawean Island: A Review
Get PDFBawean Island displays significant natural potential with abundant natural resources and natural beauty that is attractive for tourism and industrial development. However, this potential is threatened by various environmental and socio-economic problems such as limited availability of clean water, erosion of coastal structures, accumulation of rubbish, economic challenges, and low levels of community education. To overcome these challenges, an integrated and sustainable approach is needed that involves the government, community, and other related parties in sustainable natural resource management and considers ecological, economic, and social aspects. Systematic analysis is carried out to understand the potential of coastal natural resources and the problems that threaten the ecosystem. An integrated and sustainable approach is needed, involving collaboration between government, society, and related parties. The integration of new technologies, including renewable energy technologies, was identified as a potential solution to several specific problems, such as waste management and clean water supply. An integrated and sustainable approach is analyzed by involving collaboration between government, society, and related parties. With collaboration and a deep understanding of the challenges and potential of Bawean Island, it is hoped that a sustainable coastal ecological balance can be achieved for the welfare of the environment and local communities
Factors in an Effort to Acquire the Efficiency of the Cargo Compartment Design on Tankers
Get PDFTankers are one of the popular modes of transportation associated with liquid cargo. Efficiency with respect to the volume of cargo transported by tankers is an essential consideration in the transportation business process, especially fuel oil, which has become a benchmark for the global economy recently. Various studies have been carried out to optimize cargo space. This study aims to define the factors that influence cargo compartment efficiency to increase the effectiveness in the transportation business. In this study, it is known that the transverse bulkhead arrangement affects the payload capacity, which is related to the criteria in the naval architect principle. The hopper design also influences the optimization of cargo volume, which can provide benefits in terms of payload. Excess cargo volume on existing ships due to hopper design optimization, the future ship design can reduce the length of the cargo compartments that still meet the desired payload. Reducing the length of the cargo hold will undoubtedly provide an opportunity to optimize the scantling analysis for longitudinal and transverse ship structures. This study is expected to be a reference and a more detailed discussion regarding the efficiency of cargo space on tankers in the future
Design of density and density calculator as a basic physics experiment tool
Get PDFOne of the characteristics of liquid fluid is that it has a density. Many research methods have been carried out on this case, therefore in this study a simple method of measuring density was developed accompanied by a specific gravity connected via PC. The prototype consists of a loadcell sensor with the HX711 module which can convert the change in strain or resistance into a form of tension, a flow sensor is used to measure the volume of a liquid fluid through the input debit of liquid fluid flow in the measuring cup, and a mini pump equipped with a high and low relay mode with a voltage of 12 volts. The object of this study uses 3 types of fluids namely water, sugar water, and salt water. Measurement experiments were carried out by injecting the liquid by turning on the pump using the start button on the interface and pressing the stop button when it reaches the desired setpoint. Data from the volume of the liquid is obtained then compared with the results of density and specific gravity measurements theoretically. From the results of calculations and data analysis of 3 liquid fluids using static characteristics, the error value is 4,14% for water, 11,25% for sugar solution, dan 23,5% for salt solution
Estimation of Optimum Main Engine Power for a 14.5 m Wooden Purse Seine Vessel (Case Study of Motor Vessel (MV) Putra Abadi)
Get PDFSmall pelagic purse seine vessels in Jakarta are dominated by vessels with a length of 14.5 m. The vessel's hull construction was made by a traditional vesselyard using wood. The construction process only relies on the skills and habits of craftsmen. The choice of engine is only based on the size of the vessel and the price of the engine without calculating resistance. In general, the power of the purse seine main engine as the main mover is not suitable, causing wasteful fuel consumption. The fishing vessel engine used by MV Putra Abadi comes from a modified truck engine so that the fuel used does not comply with specifications. This research aims to determine the amount of power needed to move a Putra Abadi fishing vessel. The method used is direct observation by taking direct measurements of the dimensions of MV Putra Abadi. Next, the engine resistance and power are also calculated using the Holtrop resistance method in software. The Putra Abadi fishing vessel based on hydrostatic calculations showed that the block coefficient (Cb) is 0.425 at a speed of 7 knots, the resulting resistance is 2.5 kN. While at a maximum speed of 8 knots the BHP is 98.82. The power requirement of Putra Abadi fishing vessel according to this calculation is only 46% of the engine power currently used
Dinamika Kepemimpinan KGPAA Mangkunagoro IX Dan KGPAA Mangkunagoro X Dalam Peningkatan City Branding Kota Surakarta
Get PDFEksistensi city branding tidak dapat terlepas dari peran stakeholder yang terlibat didalamnya. Peran pemerintah, swasta, masyarakat, komunitas lokal, dan media yang turut serta dalam upaya penguatan city branding Kota Surakarta. Tidak terkecuali institusi budaya seperti Puro Mangkunegaran yang menjadi salah satu ikon budaya dan destinasi favorit untuk wisatawan mancanegara yang mengunjungi Kota Surakarta. Batasan dalam penelitian ini adalah kepemimpinan KGPAA Mangkunagoro IX dan KGPAA Mangkunagoro X karena city branding Kota Surakarta ditetapkan sejak tahun 2008. Penelitian ini bertujuan untuk menggambarkan perkembangan kepemimpinan KGPAA Mangkunagoro IX dan KGPAA Mangkunagoro X dalam peningkatan city branding Kota Surakarta. Metode yang digunakan yaitu metode studi kasus dengan tipe studi kasus tunggal holistik. Hasil analisis menunjukkan bahwa terdapat perkembangan yang positif sejak pergantian kepemimpinan KGPAA Mangkunagoro IX ke KGPAA Mangkunagoro X. Hal ini ditandai dengan adanya peningkatan jumlah kunjungan wisatawan ke Kota Surakarta dimana salah satunya adalah kontribusi Puro Mangkunagoro
Comprehensive Calculation of Vanadium Redox Flow Battery Capacity For 5kW Lighting Applications
Get PDFVanadium Redox Flow Batteries (VRFB) have emerged as a potential solution for renewable energy storage due to their scalability and long lifetime. However, optimizing their operational efficiency and addressing the issue of parameter accuracy for the right load pose significant challenges. This paper aims to quantify the critical parameters of VRFBs and analyze their performance in powering the system under various flow rate operating conditions. Simulations are performed using MATLAB software and unit blocks to evaluate the behavior of VRFBs during discharge and charge conditions at three electrolyte flow rates: 10, 5, and 1 liter per minute (lpm). The analysis focuses on key parameters, including operating duration, charge/discharge time, and state of charge. The results show that higher flow rates increase the discharge duration, while lower flow rates lead to shorter operating times and more pronounced ripples caused by pump control instability and electrolyte density variations. Therefore, designing appropriate parameters in VRFB systems is critical to developing sustainable energy storage solutions and supporting the implementation of clean energy technologies
Pemodelan Kasus Tuberkulosis di Jawa Tengah dengan Geographically Weighted Negative Binomial Regression
Get PDFTuberkulosis (TB) dianggap sebagai permasalahan kesehatan global yang utama karena menjadi salah satu penyakit menular yang mematikan di seluruh dunia. World Health Organization (WHO) mengategorikan sebanyak 30 negara di dunia dengan beban tinggi kasus TB dengan Negara Indonesia menempati peringkat kedua dalam kategori beban tinggi tersebut. Salah satu provinsi dengan penderita terbanyak kasus TB adalah Provinsi Jawa Tengah. Banyaknya penderita TB di Kabupaten Jawa Tengah menunjukkan bahwa terdapat faktor-faktor yang memengaruhi tingginya kasus TB, sehingga perlu dilakukan analisis secara statistik untuk mengetahui penyebab terjadinya permasalahan tersebut sekaligus mendukung tercapainya target yang berkaitan dengan target SDGs pada poin 3.3, yaitu untuk mengakhiri epidemi TB. Pada jumlah kasus TB yang berupa data diskrit, regresi Poisson merupakan metode yang sesuai untuk memodelkan data diskrit dengan asumsi ekuidispersi yang harus terpenuhi. Namun, untuk kasus TB di Jawa Tengah asumsi tersebut tidak terpenuhi, dengan kata lain terdapat overdispersi. Overdispersi dapat ditangani dengan regresi Binomial Negatif, tetapi dengan mempertimbangkan faktor spasial metode yang sesuai untuk digunakan adalah Geographically Weighted Negative Binomial Regression (GWNBR). Hasil diperoleh fungsi pembobot untuk GWNBR adalah Fixed Gaussian dengan nilai CV terkecil 4427790. Pemodelan dengan GWNBR lebih baik dalam memodelkan jika dibandingkan dengan regresi global. Hal ini diperkuat oleh nilai AIC terkecil, yakni 370,14 sehingga permasalahan overdispersi sudah teratasi. Kemudian, variabel yang berpengaruh signifikan pada setiap kabupaten dan kota di Jawa Tengah adalah persentase rumah tangga yang memiliki sumber air minum layak, jumlah tenaga kesehatan, rasio jenis kelamin, dan jumlah penduduk usia produktif dengan besar pengaruh yang berbedabeda
Role of Limestone Addition in Improving the Initial Compressive Strength of Geopolymer Concrete for Corrosive Environment Repair
Get PDFGeopolymer Concrete (GC) is highly durable in corrosive environments, making it a viable material for repair. However, its initial compressive strength was below the 7 MPa required at 1-day age. Adding fine limestone (45 μm) can improve GC's density and early strength. This study explores the effects of adding 0, 3, 5, and 7% limestone and 1% sucrose superplasticizer to GC 16M. The compressive strength was tested at 1, 3, 7, and 28 days, along with slump, permeability, and resistivity tests to assess the durability. The results show that adding 5% limestone yields the optimal GC performance for repairing corrosive environments. The compressive strengths were 15.96, 28, 43, and 67.14 MPa at 3 days, 43 MPa at 7 days, and 67.14 MPa at 28 days, with a slump of 120 mm. The permeability and resistivity results were 0.128 E-16 m² and 57.87 kΩ-cm, indicating normal corrosion levels. These findings confirm that GC with 5% limestone meets the durability and strength requirements of repair materials in corrosive environments
Liquid-Liquid Equilibrium of Propionic Acid + H2O + 1-Pentanol and Propionic Acid + H2O + 1-Hexanol at Temperatures of 303.15 and 323.15 K
Get PDFThis study aims to measure the liquid-liquid equilibrium of the ternary system of propionic acid + H2O + 1-pentanol and propionic acid + H2O + 1-hexanol at temperatures of 303.15 and 323.15 K at atmospheric pressure. The primary equipment used in this study is an equilibrium cell with a heating jacket. The experiment lasted for 24 hours with time weighting, which included 4 hours of stirring using a magnetic stirrer. The remaining 20 hours were allotted for the solution to settle until perfect equilibrium occurred. Gas Chromatography with an FID-type detector was used to analyse the experimental results for composition. Other variables were tested by conducting experiments and the results were plotted on a ternary diagram with 8 tie lines for each system. The ternary diagram indicates that both systems adhere to the Treybal type I. The NRTL and UNIQUAC equations were used to correlate the research data from each system, resulting in a Root Mean Square Deviation (RMSD) of 3.20% of the equilibrium composition for each system