Judul: Some Changes in Specification of Fishing Units and Fishing Areas of Shark Fishers From Tanjung Luar, East Lombok
Abstrak: Nelayan Tanjung Luar menggunakan rawai hanyut dan rawai dasar untuk menangkap hiu. Hiu lanjaman (C. falciformis), salah satu jenis yang tercantum pada Appendiks II CITES, adalah jenis ikan yang dominan tertangkap. Pemerintah Indonesia memerlukan sejumlah informasi dalam pengelolaan perikanan ini dengan melakukan pemantauan. Informasi yang diperlukan seperti, komposisi hiu yang tertangkap, perkembangan unit penangkapan, daerah penangkapan serta persepsi nelayan. Informasi tersebut berguna untuk menyusun strategi pengelolaan perikanan hiu. Penelitian bertujuan mengidentifikasi perubahan spesifikasi unit penangkapan, daerah penangkapan, komposisi hasil tangkapan selama 2014-2020, persepsi serta optimisme nelayan hiu. Pengumpulan data melalui pengamatan lapang dan mewawancarai 30 nelayan serta analisis statistik perikanan Dinas Kelautan dan Perikanan NTB yang bersumber dari hasil pemantauan Wildlife Conservation Society. Analisis deskriptif dan buffer analysis dilakukan terhadap data yang diperoleh. Hasil penelitian menunjukkan jumlah kapal penangkap hiu berkurang karena rusak, jumlah maksimum pancing yang dibawa berkurang sesuai dengan kebijakan lokal. Daerah operasi penangkapan hiu cenderung mengarah ke timur, fokus pada perairan sebelah barat Pulau Sumba. Ukuran hiu lanjaman yang tertangkap semakin besar, petunjuk bahwa stok hiu lanjaman dalam status terjaga, porsi hiu lanjaman yang tertangkap rawai hanyut semakin banyak sedangkan yang tertangkap rawai dasar semakin sedikit. Nelayan masih optimis dengan penangkapan hiu sebagai mata pencaharian utama mereka., Fishers from Tanjung Luar operate drift longlines and bottom longlines to catch sharks. Silky sharks (C. falciformis), a species under CITES Appendix II, is a dominant species of their catch. Government of Indonesia needs some information for managing the fisheries by conducting monitoring program. The information needed includes, among others, the species composition of captured sharks, changes in fishing units and fishing ground, and the fishermen's perception. This information can be used for determining fisheries management strategies. This study aims to identify some changes in the specifications of fishing units, fishing grounds, catch composition, perceptions and optimism of the fishers during 2014-2020. Data collection was conducted through field observations, interviews with 30 fishers and some analysis on fisheries statistics from the Agency of Marine Affairs and Fisheries of NTB generated from monitoring program conducted by the Wildlife Conservation Society. Descriptive and buffer analysis were performed to provide the needed information. The results showed a reduction in the number of shark fishing vessels due to physical damage and reduction in the number of fishing hooks per fishing vessel due to local fisheries regulation. Fising operation for shark has been shifting eastward with a focus of around the western waters of Sumba Island. The capture size of the silky shark is getting larger, an indication of a stable status of the fish stock, the portion of the silky shark in the catch from the drift longlines has been increasing while that from the bottom longines is getting fewer. Fishers are still optimistic about their fisheries as their livelihood.
Keyword: capture fisheries, CITES, shark conservation, shark fishing

Judul: Growth of Lanjaman Shark (Carcharhinus falciformis) Landed in PPI Tanjung Luar, East Lombok
Abstrak: Carcharhinus falciformis merupakan salah satu jenis ikan hiu yang tertangkap dengan intensitas tinggi di wilayah Tanjung Luar, Lombok Timur. Penelitian ini bertujuan menganalisis pertumbuhan ikan hiu lanjaman yang dominan tertangkap dan didaratkan di Tanjung Luar, Lombok Timur, serta memberikan saran rekomendasi dalam pengelolaan konservasi. Data penelitian merupakan data hasil tangkapan selama periode waktu Juli 2016 sampai dengan Agustus 2018, dengan data yang digunakan dalam penelitian ini adalah data panjang, bobot, dan jenis kelamin. Jumlah total ikan contoh sebanyak 6931 ekor dengan jantan dan betina masing-masing 2866 dan 4065 ekor. Hasil nilai uji t melalui analisis hubungan panjang bobot menunjukkan bahwa hiu lanjaman jantan dan betina di tahun 2016 memiliki pola pertumbuhan alometrik negatif, sedangkan hiu jantan dan betina di tahun 2018 memiliki pola pertumbuhan alometrik positif. Nisbah kelamin jantan lebih sedikit dibanding jumlah betina dengan perbandingan 1:1,42. Parameter pertumbuhan menunjukkan bahwa koefisien pertumbuhan (K) hiu jantan di tahun 2016 dan 2017 lebih tinggi dibandingkan ikan betina, sedangkan nilai K jantan di tahun 2018 lebih rendah dibanding betina., Carcharhinus falciformis is one type of shark that is caught with high intensity in the Tanjung Luar area, East Lombok. This study aims to analyze the growth of lanjaman shark which caught and landed at the study site. The research data is catch data during the period July 2016 to August 2018, with the data that used in this study is length, weight, and sex. The total number of sample fish was 6931 individuals with 2866 and 4065 on males and females respectively. The results of the t-test value through analysis of the relationship between length and weight show that male and female lanjaman sharks in 2016 had a negative allometric growth pattern, while male and female sharks in 2018 had a positive allometric growth pattern. Sex ratio of male sharks (C. falciformis) was less than the number of females with a ratio of 1:1.42. The growth parameters show that the growth coefficient (K) of male sharks in 2016 and 2017 is higher than the female sharks, while the K value of males in 2018 is lower than the females.
Keyword: Carcharhinus falciformis, Growth, Tanjung Luar

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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