Judul: Characteristics of the Boat-operated Lift Nets  Based at Carocok (Tarusan) Fishing Port, West Sumatra
Abstrak: Bagan perahu merupakan alat tangkap dominan yang beroperasi di perairan sekitar PPP Carocok (Tarusan). Hal ini berpotensi mempengaruhi ekosistem, khususnya ikan terget di daerah penangkapan ikan. Penelitian ini bertujuan mendeskripsikan karakteristik perikanan bagan perahu yang berbasis di PPP Carocok (Tarusan), Pesisir Selatan; dan menganalisis ikan target dan tingkat trofik hasil tangkapan bagan perahu di lokasi studi. Hasil penelitian menunjukkan bahwa bagan perahu di perairan Carocok (Tarusan) memiliki dua kelompok ukuran yaitu > 21 GT dan ≤ 21 GT. Ikan target tangkapan bagan perahu ≤ 21 GT adalah ikan teri (Stolephorus commersonnii) dan bagan perahu > 21 GT adalah ikan tongkol (Auxis thazard) dan ikan layang biru (Decapterus macarellus). Pola pertumbuhan ikan teri bersifat alometrik negatif, sementara ikan tongkol memiliki sifat isometrik. Ukuran layak tangkap ikan teri sebesar 65,7% tertangkap, ikan tongkol sebesar 65% tertangkap, dimana didominasi oleh tingkat trofik ke 3 (omnivora yang cenderung pemakan hewan) pada hasil tangkapannya., Boat-operated lift nets is the dominant fishing gear operating in the fishing ground of the fisher based in the coastal fishing port of Carocok (Tarusan). It potentially affects the ecosystem, mainly fish targets in the fishing ground. This study aims to describe the characteristics of the boat-operated lift nets fishery based at the coastal fishing port of Carocok (Tarusan), Pesisir Selatan; and to analyze fish target and trophic levels caught by the boat in the study area. The results of this study showed that the boat-operated lift nets in the waters had two size groups of the fishing vessels, namely > 21 GT and ≤ 21 GT. The target fish caught by boat-operated lift nets ≤ 21 GT was commerson's anchovy (Stolephorus commersonnii), while > 21 GT was frigate tuna (Auxis thazard) and mackerel scad (Decapterus macarellus). The commerson's anchovy growth pattern in the study area indicated a negative allometric, while frigate tuna was isometric. About 65.7% of the commerson's anchovy catch was higher than biological allowable catch size (length at first maturity), while the frigate tuna was about 65% of the total caught. Additionally, the catch of the boat-operated lift net was dominated by the group of fish in the trophic level 3 (omnivores with a preference for animals).
Keyword: boat-operated lift nets, biological allowable catch size, fish target, trophic level

Judul: komposisi hasil tangkapan, pola musim, dan analisis finansial bagan perahu di pelabuhan perikanan pantai carocok tarusan
Abstrak: Penangkapan ikan menggunakan alat tangkap bagan perahu banyak dilakukan oleh nelayan di PPP Carocok Tarusan. Tujuan penelitian adalah mengidentifikasi komposisi hasil tangkapan bagan perahu, pola musim hasil tangkapan bagan perahu, dan menentukan kelayakan finansial operasi penangkapan bagan perahu. Metode penelitian yang digunakan adalah observasi dan mengambil sampel nelayan yang diwawancarai menggunakan teknik purposive sampling. Analisis data yang digunakan yaitu komposisi hasil tangkapan dalam bentuk grafik, analisis data pola musim penangkapan menggunakan analisis deret waktu dengan metode rata-rata bergerak dan analisis kelayakan finansial. Hasil penelitian menunjukkan bahwa hasil tangkapan utama memiliki persentase 84,9%, hasil tangkapan sampingan memiliki persentase 15,1% dan Usaha perikanan tangkap bagan perahu di Carocok Tarusan dikatakan layak dengan nilai R/C sebesar 1,61 dan PP 8 bulan. Hasil tangkapan utama meliputi ikan tongkol (Auxis thazard), teri (Stolephorus indicus), layang (Decapterus macrosoma), kembung (Rastrelliger brachysoma), dan cumi-cumi (Loligo sp.).
Keyword: bagan perahu, catch, Carocok Tarusan Fishing Port, seasonal pattern

Judul: The Exploration of Discrete Logarithm over Finite Field GF(3m)
Abstrak: The security of many public~key algorithms is based on the problem of finding discrete logarithms. The generalized discrete logarithm problem is the following: given a finite cyclic group G of order n, a generator a of G, and an element fl E G, find the integer x, 0 ~ x ~ n - 1, such that 0: = fl. Algorithm for discrete logarithm problem focused on Menezes et al. (1997) that consist of exhaustive search algorithm, the baby-step giant-step algorithm, Pollard's rho algorithm, Pohlig-Hellman algorithm, and index-calculus algorithm. These algorithms are explorated to be used in discrete logarithm problem over finite field GF(3m ). The exploration also produces some algorithms, i.e. naif negative algorithm, baby-step mother-step algorithm, baby-step mother free-step algorithm, and baby-step free-step algorithm. All algorithms implemented using Maple 11. The Pohlig-Hellman and baby-step giant-step algorithms are efficient enough to be used in discrete logarithm problem over finite field GF(3m ) for m < 20.
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