Judul: Kinerja Usaha Pendederan Kerapu Cantik Epinephelus fuscoguttatus-microdon di KJA dengan Perbedaan Frekuensi Pemberian Pakan
Abstrak: Pakan merupakan aspek penting dalam usaha budidaya dikarenakan selain menghabiskan 60-70% biaya operasional, juga mempengaruhi kinerja usaha pendederan ikan kerapu. Manajemen pemberian pakan yang optimal dapat meningkatkan kinerja usaha pendederan ikan kerapu. Penelitian ini bertujuan mengevaluasi frekuensi pemberian pakan formula secara at satiation pada pendederan ikan kerapu cantik dalam keramba jaring apung, terhadap kinerja produksi dan keuntungan usaha. Terdapat tiga perlakuan yaitu pemberian frekuensi pakan dua kali sehari (A), pemberian frekuensi pakan tiga kali sehari (B), dan pemberian frekuensi pakan empat kali sehari (C). Benih ikan kerapu cantik berukuran 8-9 cm dipelihara dalam KJA berukuran 1 m x 1 m x 1,5 m dengan padat tebar 50 ekor/m3. Ikan dipelihara selama 40 hari dengan metode pemberian pakan at satiation. Hasil penelitian ini menunjukkan bahwa perlakuan B memberikan kinerja produksi terbaik seperti tingkat kelangsungan hidup 98,67%; pertumbuhan panjang 4,86; rasio konversi pakan 1,29; laju pertumbuhan panjang spesifik sebesar 1,10±0,03 %/hari; dan laju pertumbuhan panjang mutlak sebesar 0,12±0,003 cm/hari sehingga menghasilkan kinerja usaha terbaik dengan keuntungan sebesar Rp. 272.616.856 per tahun., Feed is an important aspect in the cultivation business because in addition to spending 60-70% of operational costs, it also affects the performance of grouper fish nursery business. An optimal feeding management can improve the performance of grouper fish nursery. This study aimed to evaluate feeding frequencies commercial food with at satiation method in floating net cage to production performance and business profit. There were three treatments used, those were feeding frequency twice a day, feeding frequency three times a day, and feeding frequency four times a day. Cantik grouper fish seeds measuring 8-9 cm were preserved in sea FNC measuring 1 m x 1 m x 1.5 m with a density of 50 fish/m3. Fishes were maintained for 40 days by the method of feeding at satiation. The results of this study showed that treatment B provided the best production performance such as a survival rate of 98.67%; long growth of 4.86 cm; feed conversion ratio 1.29; specific long growth rate of 1.10±0.03 %/day; and the absolute long growth rate of 0.12±0.003 cm/day so that produced the best business performance with a profit Rp. 272,616,856 per year.
Keyword: grouper, NFC, nursery

Judul: Production Performance and Nursery Business for Cantang  Grouper in a Flow-Through System with Different Daily Water Changes
Abstrak: Penerapan pergantian air yang optimal dapat meningkatkan kinerja produksi dan usaha pendederan ikan kerapu. Penelitian bertujuan menganalisis persentase pergantian air harian yang berbeda untuk menghasilkan kinerja produksi dan usaha pendederan ikan kerapu cantang (Epinephelus fuscoguttatus >< E. lanceolatus) terbaik yang dipelihara menggunakan sistem flow-through. Terdapat tiga perlakuan dan tiga kali pengulangan yang diujikan, yaitu pergantian air 100%, 200%, dan 300 %/hari. Benih ikan kerapu cantang dipelihara dalam bak fiber bundar dengan volume 1 m3 yang dikumpulkan di dalam hatchery dengan ukuran tebar 12,7±0,22 cm. Benih ikan kerapu dipelihara dengan kepadatan 20 ekor/m3 selama 40 hari dan diberi pakan berupa pelet dengan protein 48% sebanyak 3 kali sehari secara at satiation. Hasil penelitian menunjukkan bahwa perlakuan pergantian air 300 %/hari memberikan kinerja produksi lebih baik, dengan tingkat kelangsungan hidup 90%, rasio konversi pakan 1,46, laju pertumbuhan panjang spesifik sebesar 1,05±0,04 %/hari, laju pertumbuhan panjang mutlak sebesar 0,16±0,01 cm/hari, panjang panen 17,3±0,38 cm, serta kinerja usaha terbaik dengan keuntungan tertinggi sebesar Rp20.804.102 per tahun, R/C rasio tertinggi 1,18, dan payback period terendah 8,72 tahun., The optimal application of water changes can enhance production performance and the business of grouper nurseries. This research aims to analyze the different daily water change percentages for achieving the best production performance and nursery business for cantang grouper (Epinephelus fuscoguttatus >< E. lanceolatus) reared using a flow-through system. There were three treatments with three replications were tested; 100%, 200%, and 300 %/day. Cantang grouper fry are reared in round fiber tanks with a volume of 1 m3 which are collected in the hatchery with a stocking size of 12.7±0.22 cm. Grouper fry were reared at a density of 20 fish/m3 for 40 days and fed with pellets containing 48% protein, three times a day at satiation. The results showed that the 300%/day water change treatment provided better production performance, with a survival rate of 90%, a feed conversion ratio of 1.46, a specific length growth rate of 1.05±0.04 %/day, a absolute length growth rate of 0.16±0.01 cm/day, harvest length of 17.3±0.38 cm, as well as the best business performance with the highest profit of IDR 20,804,102 per year, the highest R/C ratio of 1.18, and the lowest payback period of 8.72 years.
Keyword: fiber tank, fry, harvest lenght, water change, profit

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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