Judul: Grow Out Production Performance of Spiny Lobster Panulirus homarus in Floating Net Cage with Different Light Intensity
Abstrak: Lobster memiliki mata dengan tipe ”superposition” yang terbuka dan bekerja dengan baik hanya pada intensitas cahaya yang rendah. Sejauh ini masih sedikit informasi intensitas cahaya yang baik untuk kehidupan dan budidaya lobster. Penelitian ini bertujuan menganalisis perbedaan intensitas cahaya terhadap kinerja produksi lobster pasir dalam karamba jaring apung. Penelitian mengunakan Rancangan Acak Lengkap (RAL) dengan dua perlakuan yaitu terang (satu lapis penutup, intensitas cahaya 14.910 lux) dan redup (tiga lapis penutup, 4.619 lux), masing-masing dengan tiga ulangan. Lobster berukuran rata-rata 100 g dan panjang 14,45 cm dipelihara dengan padat tebar 8 ekor/m² dalam hapa berbahan waring berukuran 1 x 1 x 1 m³ yang ditempatkan dalam karamba jaring apung (KJA). Penelitian dilakukan selama 40 hari di Balai Sea Farming Pusat Kajian Sumber Daya Pesisir dan Lautan (PKSPL) IPB, Perairan Gosong Semak Daun, Kepulauan Seribu. Lobster diberi pakan berupa ikan rucah sebanyak 10 % dari bobot biomasa perhari, satu kali dalam sehari pada pukul 16.00 WIB. Hasil penelitian menunjukan pemberian intensitas cahaya redup dalam hapa di KJA memberikan laju pertumbuhan bobot mutlak lobster yang lebih tinggi (P<0,05). Parameter kinerja produksi lobster lainnya yang diberi cahaya terang dan redup menunjukan nilai yang sama., Lobsters have eyes with a "superposition" type that are open and work well only at low light intensity. So far there is still little information on light intensity that is good for the life and cultivation of lobsters. This research aims to analyze differences in light intensity on the production performance of sand lobsters in floating net cages. The research used a Completely Randomized Design (CRD) with two treatments, namely bright (one layer of cover, light intensity 14,910 lux) and dim (three layers of cover, 4,619 lux), each with three replications. Lobsters with an average size of 100 g and a length of 14.45 cm are reared at a stocking density of 8 individuals/m² in a 1 x 1 x 1 m³ waring-made hapa placed in a floating net cage (KJA). The research was conducted for 40 days at the Sea Farming Center, Center for Coastal and Marine Resources Studies (PKSPL) IPB, Gosong Semak Daun Waters, Seribu Islands. Lobsters are given food in the form of trash fish at 10% of the biomass weight per day, once a day at 16.00 WIB. The results showed that providing low light intensity in the hapa in KJA provided a higher absolute weight growth rate for lobsters (P<0.05). Other lobster production performance parameters given bright and dim light showed the same values.
Keyword: light intensity, lobster, shady, light

Judul: Production Performance of Spiny Lobster  Panulirus homarus Grow-out at in Submersible Net Cage with Different Depths
Abstrak: Suhu, intensitas cahaya, gelombang, kekeruhan, arus, dan tekanan dipengaruhi oleh kedalaman perairan. Kinerja produksi lobster pasir akan maksimal apabila diiringi dengan penyesuaian lingkungan budidaya dengan habitat alaminya. Tujuan penelitian ini adalah menentukan kedalaman optimal bagi kehidupan lobster untuk meningkatkan kinerja produksi dan keuntungan di Karamba Jaring Tenggelam. Penelitian ini menggunakan Rancangan Acak Lengkap dengan tiga kedalaman berbeda, yaitu 1 m, 2 m, dan 3 m di bawah permukaan air laut dengan tiga kali ulangan. Sebanyak 72 ekor lobster dipelihara di dalam karamba berukuran (1 x 1 x 1) m dengan kepadatan 8 ekor/m2 dan bobot rata-rata 80,14+0,33 g selama 40 hari. Pemberian pakan dilakukan sebanyak 2 kali sehari dengan bobot 5% dari biomassa lobster. Parameter uji pada penelitian ini meliputi kinerja produksi, kualitas air, dan analisis usaha. Data dianalisis menggunakan ANOVA pada selang kepercayaan 95%. Hasil penelitian menunjukkan tingkat kedalaman yang optimal pada penelitian ini untuk meningkatkan kinerja produksi pada pembesaran lobster pasir di karamba jaring tenggelam adalah kedalaman 2 m. Pada kedalaman tersebut, lobster memiliki hasil kinerja produksi terbaik, yang ditunjukkan dengan nilai produktivitas yang paling tinggi. Sedangkan kedalaman 3 m memiliki R/C rasio tertinggi dan PP yang lebih singkat dalam usaha budidaya lobster pasir pada sistem Karamba Jaring Tenggelam., Temperature, light intensity, waves, turbidity, currents, and pressure are affected by water depth. The performance of spiny lobster production will be maximized if it is accompanied by adjustment of the cultivation environment to its natural habitat. The purpose of this study was to determine the optimal depth for lobster life to increase production performance and profitability in the Submersible Net Cages. This study used a completely randomized design with three depths, namely 1 m, 2 m, and 3 m below sea level, with three replications. A total of 72 lobsters were kept in cages measuring 1 m x 1 m x 1 m with a density of 8 fish/m2 and an average weight of 80.14±0.33 g for 40 days. Feeding was carried out 2 times a day with a weight of 5% of the lobster biomass. The test parameters in this study include production performance, water quality, and business analysis. Data were analyzed using ANOVA at 95% confidence interval. The results showed that the optimal level of depth in this study to improve production performance on rearing spiny lobster in Submersible Net Cages was 2 m. At this depth, lobster has the best production performance, indicated by the highest production value. At the same time, the depth of 3 m has the highest R/C ratio and shorter PP in spiny lobster cultivation in the Submersible Net Cage system.
Keyword: cages, depth, production performance, spiny lobster

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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