Center for Scientific Publication
Not a member yet
4029 research outputs found
Sort by
INSPECTION OF THE ADEQUACY OF CLOSED-DRAIN AND OPEN-DRAIN SYSTEMS USING HYDRAULIC ANALYSIS FOR AGING OFFSHORE PLATFORMS
Full text linkAging offshore platforms require a reliable drainage system to ensure safety and operational efficiency. This study aims to analyze the adequacy of the closed drain and open drain systems on a 24-year-old offshore platform that is scheduled for redevelopment. The methodology employed involves hydraulic analysis, considering fluid production rates and drainage system design data based on API 14E and GPSA (2004) standards. The collected data included channel cross-section dimensions, flow rates, and fluid characteristics to calculate the system's capacity. The analysis showed that the 4-inch header pipe was adequate to accommodate a closed drain flow rate of 167.4 BPD and an open drain flow rate of 1.63 BPD. The Slop Tank (Platform X-T-26), with a geometric volume of 54 ft3, was also adequate to contain the maximum drainage volume of 15.23 ft3 from the Vertical Test Separator. This study also identified several critical points that require periodic monitoring to prevent blockages and performance degradation. This study emphasizes the importance of periodic inspections to assess the adequacy of drainage systems on aging offshore platforms to ensure safety and operational efficiency after redevelopment. It also provides preventive maintenance recommendations to extend the system's lifespan
Actors in Preservation Local Wisdom: Mangure Lawik for Sustaining Marine Resources
Full text linkMangure Lawik is a maritime hospitality activity developed by the ancestors of the Sibolga community and has been passed down continuously from one generation to the next. However, some people in Sibolga have experienced changes following the wave of modernization and have begun to abandon their customs. This paper aims to examine the history of Mangure Lawik, analyze the roles, interests, and influences of each stakeholder, and see the impact of this tradition on marine resources using ethnographic methods assisted by Stakeholder Analysis, it was concluded that the history of Mangure Lawik is divided into three periods (early, middle & present). This study also shows that there are 17 stakeholders consisting of 5 main stakeholders, 6 primary stakeholders, and 6 secondary stakeholders. The role of stakeholders is divided into four categories, namely: Policy Makers, Coordinators, Facilitators, and Implementers, where each stakeholder has carried it out well so that the Mangure Lawik tradition can continue. In its implementation, Mangure Lawik impacts the diversity of coastal and marine resources, because it indirectly invites the community to manage and protect coastal and marine resources, maintain the balance of aquatic ecosystems, and prevent coastal environmental pollution
Degradation of Lignocellulose Biomass into Bio-oil and Biochar by Hydrothermal Liquefaction (HTL)
Full text linkCommunities around the world are becoming more concerned about the environmental impact of using and heavily relying on fossil fuels, leading to a growing popularity of sustainable energy solutions. Biomass energy has become a popular topic of study around the world due to its sustainability. This study aims to investigate the feasibility of biomass waste valorization through its thermochemical or biochemical conversion into a sustainable, high-value energy commodity, thereby augmenting its economic and environmental value proposition. Hydrothermal liquefaction (HTL) was identified as the most effective method for treating biomass waste. Experiments were carried out by mixing water and biomass waste in a 500 mL autoclave batch reactor at temperatures ranging from 270 °C to 330 °C, with b/w ratios of 1:20, 2:20, and 3:20 and a retention time of 30 minutes. This study was additionally carried out under a starting pressure of 5 bar. Bio-oil had the highest product dispersion (84% at 330°C and a b/w ratio of 3:30). Meanwhile, the biochar yield was less than 10%. The solid product, on the other hand, had GCV values that were about the same as bituminous and sub-bituminous coals, at 6474 and 4888 cal/g, respectively. The carbon content of biochar at 270°C and 330°C is 50.86% and 66.77%, respectively, resulting from a variable b/w ratio of 2:20. GC-MS analyzed the highest-yielding product, bio-oil. The GC-MS study revealed a number of value-added chemicals resulting from the breakdown of hemicellulose, cellulose, and lignin compounds
Exploration of Premium Factors for Passenger Vessel in Indonesia
Full text linkThe premium of Indonesian marine insurance is one of the issues for maritime players in Indonesia, particularly for passenger vessels. Indonesian government also released some policies as a part of positive initiatives to bring Indonesia to the next level of maritime involvement in the world, however, the insurance side as the main risk protection of maritime operation is not positioned as the main part to be discussed. Marine insurance is the key to managing the overall risk of the passenger vessels during the operation. In fact, in Indonesia, insurance studies still have a gap in their application, particularly for the marine insurance industry and for passenger vessel insurance. The underwriter has difficulties in assessing the real risk of Indonesian passenger vessels while the shipowners do not put safety as their top priority in managing the business. This research aims to solve two main problems in Indonesian passenger vessel insurance; the first one is to identify the problems of Indonesian passenger vessel insurance and the second is to explore and identify the premium factors of Indonesian passenger vessel insurance. The study found that the big claim ratio reported over the years, the lack of marine insurance underwriters’ ability to assess the risk, the lack of marine insurance capacity, and the premium war are the main problems faced by Indonesian passenger vessel insurance players. Accordingly, this paper is also revealing several premium factors for Indonesian passenger vessel insurance; including the vessel type, GT, claim record, years of built, trading area, extent of insurance coverage, vessel condition, as well as the moral hazard from the owner and the crew
The Effect of Coconut Fiber Usage and Clamshell Powder Replacement for Calcium Silicate Board’s Bending Strength
Full text linkCalcium silicate boards (CSB) are being explored in the maritime industry due to the mechanical strength and its resintance to humidity. The common CSB comprises fiber, silica sand, and portland cement. Clamshell is one of marine waste, who has a high calcium carbonate (CaCO3) content. Coconut fiber, a natural fiber known for its high strength and durability, presents sustainable solutions for enhancing the material properties of CSB. This study explores the forming mechanism and mechanical properties of the CSB in the usage and varied volume fraction addition of coconut fiber with the varied portion replacement silica sand using clamshell powder. The bending test was performed, and the experimental results were analyzed using ANOVA, to understand the effect of the mixture composition on the bending strength of the CSB. The addition of volume fraction coconut fiber significantly improve the bending strength of the boards, while the replacement of silica sand using clamshell powder gives various result. The maximum bending strength was 13.87 ± 0.64 Mpa by 0% clamshell powder replacement in 9% coconut fiber, and significantly drop at 8.26 ± 2.20 MPa by 50% clamshell powder with 50% silica sand. In fully portion replacement of silica sand, in which the addition of 100% clamshell powder, with 9% coconut fiber, the bending strength measured at 10.29 ± 1.31 MPa. The highest results exceeding the minimum requirement in ISO-8336 category A and B (saturated condition) , class 3 (>13 MPa) standards for interior wall installations. This study providing a more robust and eco-friendly materials alternatives that supports non or maritime industry needs in while resolve the environmental issue
Fatigue Life Analysis Of Car Deck Construction on a Ferry Ro Ro
Full text linkFatigue life analysis is often overlooked in ship development, leading to an uncertain understanding of a ship’s construction lifespan. This study focuses on the fatigue life of the car deck, which is affected by deformation on a ro-ro ferry. The research aims to determine the maximum stress, location, the cause of deformation, and the fatigue life of the car deck on a ro-ro passenger ship. The calculations assess the car deck’s lifespan and provide a reference for future design considerations. Finite element analysis (FEA) is used, with fatigue life calculated using the Sonderberg method. The research begins with calculating the ship’s weight and buoyancy distribution, then determining the ship’s longitudinal strength from the load distribution. The analysis reveals that the highest stress occurs under hogging wave conditions, exceeding the yield strength of 321 MPa. Specifically, at overload and hogging wave conditions, the highest stress of 486.1 MPa is found on the starboard side between longitudinal stiffeners 1 and 2 (900 mm from the centerline), between frames 56 and 57, with a fatigue life of 4.3 years
Numerical study of the installation configuration of four Savonius hydrokinetic turbines in the cooling water channel of PAITON Power Plant
Full text linkThe energy crisis caused by decreasing fossil fuel reserves encourages the development of renewable energy, one of which is water energy from rivers, lakes, and canals. The Paiton PLTU cooling water channel, which is 2 km long, 15 m wide, and 10 m deep with a flow speed of 1-2.8 m/s, has great potential as an energy generator by installing a Savonius hydrokinetic turbine. This study aims to identify the optimal tandem spacing to avoid turbine interaction. This study uses numerical simulations using Ansys Fluent 2023 R2 with four tandem turbines rotating Counterclockwise and Clockwise. The distances between the turbines (T/D) studied are 2.1, 4.4, 60, and 300. At close T/D distances (2.1 and 4.4), the turbines influence each other, reducing the performance of the front turbine. When the distance increases to T/D = 60, the rear turbine influence decreases, so the front turbine can perform similarly to a single turbine. At T/D = 300, both turbines operate optimally with minimal interaction, achieving efficient performance and increased torque and power output
Smart Furniture Rak Multifungsi Museum Musik Indonesia
Full text linkMuseum Musik Indonesia (MMI) yang terletak di Perumahan Griya Shanta Blok B, Jl. Sukarno Hatta, Kota Malang, Jawa Timur merupakan satu-satunya museum seni musik di Indonesia. Koleksi MMI sebagian besar adalah berupa media rekam fisik yang berupa kaset, piringan hitam/vinyl, VCD/DVD yang mayoritas koleksinya bersumber dari sumbangan masyarakat. Pengambilan data penelitian menggunakan metodologi kualitatif dengan melakukan wawancara kepada pengelola museum dan observasi secara langsung untuk studi kebutuhan ruang dan fasilitas. Kegiatan observasi menemukan beberapa permasalahan, diantaranya adalah jumlah koleksi yang banyak namun luas area museum, jumlah furnitur untuk display dan tempat penyimpanan yang terbatas. Pengelola merasa kesulitan untuk menyimpan, menata dan memamerkan koleksi MMI dengan baik dan menarik. Solusi untuk mengatasi permasalahan tersebut adalah membuat smart furniture berbentuk rak dengan konsep multifungsi. Perancangan smart furniture menggunakan metode design thinking double diamond. Smart furniture tersebut berfungsi menjadi tempat display dan penyimpanan koleksi Museum Musik Indonesia agar penggunaan ruang menjadi lebih maksimal. Pengunjung juga dapat berinteraksi dengan koleksi melalui smart furniture tersebut. Pembuatan rak smart furniture untuk MMI diharapkan memberikan solusi dari permasalahan yang ada dan dapat memberikan kontribusi terhadap pengembangan desain museum yang lain sehingga menjadi daya tarik tersendiri bagi pengunjung yang memiliki minat terhadap koleksi museum serta menjadi inspirasi masyarakat umum untuk membuat smart furniture
Sintesis 2-Hidroksi Etil Ester Asam Lemak (2-HEE) dari Minyak Jelantah Sebagai Bioaditif Potensial Untuk Meningkatkan Lubrisitas Diesel Fosil Rendah Sulfur
Full text linkPengembangan zat aditif didorong oleh turunnya daya lubrisitas dari bahan bakar diesel fosil akibat dari proses desulfurisasi. Senyawa hidroksietil ester asam lemak (2-HEE) yang disintesis pada penelitian ini berpotensi tinggi sebagai zat aditif alami atau bioaditif. Sintesis dilakukan dengan memanfaatkan limbah minyak goreng (jelantah) melalui proses transesterifikasi dengan etilen glikol melalui senyawa intermediet berupa metil ester asam lemak (FAME). Yield FAME sebesar 85,39% dihasilkan melalui reaksi antara minyak jelantah dan metanol dengan rasio molar metanol:minyak (6:1), katalis 1% (b/b minyak), selama 165 menit pada suhu 65°C dalam sistem refluks. Analisis KG-SM dari FAME menunjukkan bahwa minyak jelantah sebagian besar terdiri dari asam palmitat dan asam oleat. FAME selanjutnya direaksikan dengan etilen glikol (EG) dengan rasio molar 2:3, menggunakan katalis heterogen CaO 1,2% (b/bminyak) selama 6 jam pada temperatur 130°C dalam sistem distilasi vakum. Produk hasil sintesis 2-HEE mengandung 31,22% hidroksietil ester palmitat dan 36,26% hidroksietil ester oleat, dengan total kelimpahan senyawa 2-HEE sebesar 78,31%. Adanya gugus hidroksi dan asam lemak tak jenuh pada kerangka struktur senyawa 2-HEE diduga potesial untuk digunakan sebagai bioaditif untuk meningkatkan lubrisitas bahan bakar diesel fosi
Kesediaan Masyarakat Jakarta Membeli Hunian Bertingkat Green Building
No full textPerubahan iklim dan degradasi lingkungan telah mempercepat adopsi konsep green building secara global. Penelitian ini bertujuan untuk mengevaluasi tingkat pemahaman masyarakat Jakarta tentang hunian bertingkat green building dan mengidentifikasi faktor faktor utama yang memengaruhi kesediaan mereka untuk membeli. Dengan pendekatan survei kuantitatif, data dikumpulkan dari responden di Jakarta. Analisis deskriptif dan inferensial dilakukan untuk mengeksplorasi hubungan antara pemahaman publik dan atribut green building, termasuk efisiensi energi, kualitas udara dalam ruangan, dan pengelolaan lingkungan. Temuan menunjukkan bahwa efisiensi energi dan kesehatan dalam ruang menjadi prioritas utama, meskipun biaya awal yang tinggi tetap menjadi hambatan signifikan. Wawasan ini memberikan rekomendasi praktis bagi pengembang dan pembuat kebijakan untuk merancang strategi green building yang lebih hemat biaya dan selaras dengan pasar