Judul: Design and Construction of Ecofriendly Line Hauler for Collapsible Trap Using 5 GT Fishing Boat
Abstrak: The blue swimming crab (rajungan) fishing industry in the coastal area of Karawang has been employing a longline system to capture crabs using traditional crab traps. To expedite and simplify the process of hauling the crab traps onto the fishing boat, fishermen have been using a line hauler, even though without considering the substantial load it exerts on the equipment. Furthermore, the existing line hauler relies on fossil fuels for operation, which is not environmentally sustainable. It also generates carbon dioxides as well as noise pollution during operation. This research aims to design and construct an eco-friendly line hauler that does not rely on fossil fuels and operates with lower noise levels. The design and construction of the line hauler prototype were conducted in several stages. Initially, hydrodynamic force estimations were made for the crab trap assembly during the hauling process. Subsequently, a prototype was designed to suit the operational environment through appropriate design selection. This was followed by functional and performance testing in a real-world environment. The final stage involved assessing positive responses toward fishers and estimating the cost of operating the prototype. The research was carried out from June 2022 to September 2023. The research methodology involved design, construction, and technical function and performance testing. Primary data collection was conducted in the form of measurement results and observations from the initial stages to the functional and performance tests. The data was processed using software and mathematical calculations, presented in tabular form. Data analysis was conducted through quantitative and qualitative comparative analysis of the existing equipment and the prototype. The research findings demonstrate that the prototype of the line hauler surpasses the existing equipment. The prototype uses electric propulsion, making it more environmentally friendly by eliminating the use of fossil fuels and operating quietly below the threshold values especially in fishing area of fishermen. The prototype when subjected to functional testing, received positive responses from the fishers operating it, and also the operationl cost significantly reduced, reaching a cost reduction of 63%., Bubu rajungan yang dioperasikan dengan sistem longline, membutuhkan alat bantu penangkapan untuk memudahkan dan mempercepat waktu penarikan bubu rajungan ke atas kapal. Nelayan buburajungan di pesisir Karawang telah menggunakan alat bantu penarik tali utama namun belum mempertimbangkan besar beban yang ditanggung oleh alat bantu serta masih menggunakan mesin penggerak yang kurang ramah lingkungan Ramah lingkungan yang dimaksud adalah alat bantu eksisting masih menggunakan bahan bakar fosil yang menghasilkan gas buang CO₂ dan kebisingan saat operasional. Tujuan dari penelitian ini adalah untuk membuat alat penarik bubu rajungan yang lebih ramah lingkungan yaitu tidak menggunakan penggerak berbahan bakar fosil dengan tingkat kebisingan dibawah Nilai Ambang Batas (NAB) yang berlaku. Dalam merancang bangun alat penarik tali bubu rajungan prototipe yang dibuat dilakukan dengan beberapa tahapan. Tahap awal dimulai dengan melakukan perhitungan estimasi gaya hidrodinamika pada rangakain bubu rajungan saat proses penarikan (hauling). Selanjutnya tahap perancangan prototipe yang sesuai dengan lingkungan operasional melalui pemilihan desain yang sesuai. Kemudian dilanjutkan dengan pengujian fungsi dan kinerja pada lingkungan yang sebenarnya. Tahap akhir adalah menggali respon positif terhadap rancang bangun kepada nelayan dan menghitung estimasi biaya
Keyword: crab traps, Line hauler, Ecofriendly

Judul: Conceptual Design of Electric Shock Device to  Facilitate the Hauling Process in Small-Scale Tuna Handline Fisheries
Abstrak: Pancing ulur tuna di Indonesia tergolong perikanan skala kecil dan umumnya tidak dilengkapi dengan alat bantu untuk menarik pancing. Hal ini seringkali menyebabkan nelayan menghadapi berbagai permasalahan seperti beban kerja yang berlebihan dan penurunan kualitas hasil tangkapan saat pancing ditarik oleh ikan tuna yang relatif besar (>10 kg). Alat untuk mempercepat proses penarikan sebenarnya sudah ada, tetapi tidak cocok untuk nelayan skala kecil. Oleh karena itu, penelitian ini bertujuan untuk membuat suatu rancangan bangun alat yang ringkas dan mudah diaplikasikan dengan menggunakan sistem kejut listrik. Metode yang digunakan adalah studi literatur dan eksperimen. Hasil penelitian menunjukkan bahwa untuk uji coba menggunakan sistem kejut listrik tipe DC dan sistem saklar menggunakan timer delay relay. Selanjutnya berdasarkan hasil perhitungan pemilihan material menunjukkan bahwa stainless steel menjadi prioritas pertama dengan nilai C sebesar 1. Sementara itu pada pemilihan bentuk, tabung dipilih sebagai desain bentuk utama karena memiliki kecepatan dan waktu tempuh tercepat dibandingkan bentuk lainnya, yaitu 2,84 m/detik dan 35,27 detik. Konstruksi untuk merakit satu unit alat kejut listrik membutuhkan setidaknya 26 komponen. Prototipe yang telah dibuat memiliki dimensi berdiameter 6 cm dan tinggi total 40 cm serta berat prototipe 2,67 kg. Hasil uji fungsional menunjukkan bahwa sistem saklardan performa alat dalam melalui senar pancing sudah berjalan dengan baik tanpa ada hambatan, namun pada hasil uji kejut listrik dan kebocoran alat perlu dilakukan modifikasi karena ditemukan kekurangan dan tidak sesuai dengan yang diharapkan yaitu ikan percobaan tidak mengalami pingsan dan alat masih mengalami kebocoran., Tuna handline in Indonesia is a small-scale fishery and is generally not equipped with tools to pull the fishing line. This often causes fishermen to face various problems such as work overload and decreasing the quality of the fish caught when the fishing line is pulled by relatively large tuna (>10 kg). Devices to accelerate the hauling process actually already exist, but they are not suitable for small-scale fishermen. Therefore, this study aims to make a design of a device that is concise and easy to apply using an electric shock system. The methods used were literature and experimental studies. The results show that for trials using a DC type electric shock system and the switch system uses a timer delay relay. Furthermore, based on the results of the calculation of material selection, it shows that stainless steel was the first priority with a C value of 1. Meanwhile, in the selection ofshapes, the tube is chosen as the main form design because it has the fastest speed and travel time compared to other forms, which is 2.84 m/s and 35.27 s. Construction for assembling one unit of electric shock device requires at least 26 components. The prototype that has been made has dimensions of 6 cm in diameter and 40 cm in total height and this prototype weighs 2.67 kg. The results of the functional test indicate that the switch system and the performance of the internal equipment through the fishing line have been running well without any obstacles, but the results of the electric shock and leakage test of the tool need to be modified because deficiencies were found
Keyword: design, electric shock device, handline, small-scale tuna fisheries, tuna

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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