Judul: Production Performance of Cantik Grouper Nursery in Floating Net Cage with Different Light Intensity
Abstrak: Kanibalisme pada benih ikan kerapu cantik mempengaruhi tingkat kelangsungan hidup, pertumbuhan, produksi dan produktivitas pada pendederan ikan kerapu cantik dalam karamba jaring apung di laut. Kanibalisme pada benih ikan kerapu cantik salah satunya dipengaruhi oleh intensitas cahaya. Penelitian ini bertujuan menganalisis pengaruh perbedaan intensitas cahaya terhadap kinerja produksi pendederan ikan kerapu cantik dalam karamba jaring apung di laut. Benih ikan kerapu cantik dengan panjang 8 cm dan bobot 11,3 g dipelihara dalam kantong waring berukuran 1 m × 1 m × 1 m dalam karamba jaring apung dengan padat tebar 50 ekor/m3 dan penggunaan paranet. Benih diberi pakan buatan berupa pelet berukuran 4 mm yang mengandung protein sebesar 37% secara at satiation antara pukul 07.00 hingga 16.00 WIB. Perlakuan satu lapis paranet menunjukkan hasil pertumbuhan, rasio konversi pakan dan produktivitas tertinggi pada pendederan ikan kerapu cantik dalam karamba jaring apung di laut., Cannibalism in cantik grouper fish fry affects survival rate, growth, production and productivity in cantik grouper fish breeding in floating net cages at sea. Cannibalism in cantik grouper fish fry is influenced by light intensity. This study aims to analyze the effect of different light intensities on the production performance of cantik grouper fish breeders in floating net cages at sea. Cantik grouper fry with a length of 8 cm and a weight of 11.3 g were reared in 1 m × 1 m × 1 m mesh bags in floating net cages with a stocking density of 50 fish/m3 and the use of paranet. The fry were fed with artificial food in the form of 4 mm pellets containing 37% protein by at satiation between 7:00 am and 4:00 pm. The one-layer paranet treatment showed the highest growth, feed conversion ratio and productivity results in cantik grouper breeding in floating net cages at sea.
Keyword: intensitas cahaya, kelangsungan hidup, kerapu, pendederan

Judul: Kinerja Produksi Pendederan Ikan Kerapu Cantang dalam Keramba Jaring Apung di Laut dengan Pencahayaan Teduh dan Terang
Abstrak: Ikan kerapu bersifat nokturnal dan memiliki sifat kanibalisme tinggi pada pemeliharaan dengan pencahayaan terlalu terang. Pendederan ikan kerapu dalam keramba jaring apung (KJA) di laut telah diaplikasikan, namun intensitas cahaya tidak terkontrol. Penelitian ini bertujuan untuk menganalisis pengaruh kondisi pencahayaan teduh dan terang melalui penggunaan penutup KJA dengan kerapatan yang berbeda terhadap kinerja produksi pendederan ikan kerapu cantang di laut. Rancangan Acak Lengkap digunakan dalam penelitian ini dengan perlakuan pencahayaan teduh (kedalaman 1 m 1472 lux dan permukaan 2405 lux) dan terang (kedalaman 1 m 3633 lux dan permukaan 16.552 lux) dan setiap perlakuan diulang tiga kali. Ikan kerapu cantang (bobot 7,18±0,17 gram dan panjang 7,06±0,051 cm) dipelihara dalam KJA selama 32 hari dengan padat tebar 100 ekor/m³ dan diberi pakan buatan berupa pelet tenggelam dengan metode ad-satiation pada 08.00, 12.00, dan 16.00 WIB. Oksigen terlarut, suhu, pH, dan salinitas air dalam KJA diukur setiap 7 hari, sedangkan ammonia setiap 2 minggu. Nilai koefisien keragaman panjang dan tingkat kanibalisme pada perlakuan teduh lebih tinggi dari perlakuan terang., Groupers are nocturnal and have high cannibalism in rearing with too bright light. Nursery of grouper in floating net cages (KJA) in the sea has been applied, but the light intensity is uncontrolled. This study aims to analyze the effect of shady and bright lighting conditions through the use of KJA covers with different densities on the nursery production performance of cantang grouper in the sea. Completely randomized design was used in this study with shady (depth 1 m 1472 lux and surface 2405 lux) and bright lighting (depth 1 m 3633 lux and surface 16.552 lux) and each treatment was three replications. Cantang grouper (weight 7,18±0,17 grams and length 7,06±0,051 cm) was reared in KJA for 32 days with a stocking density of 100 fish/m³ and given artificial feed in the form of sinking pellets by ad-satiation method at 08.00, 12.00 and 16.00 WIB. Dissolved oxygen, temperature, pH, and salinity of water in KJA were measured every 7 days, while ammonia every 2 weeks. The coefficient of length variation and the level of cannibalism in the shade treatment were higher than in the light treatment.
Keyword: floating net cages (KJA), grouper, nuersery, shady and light

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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