Judul: Efektifvitas penambahan zeolit, karbon aktif, minyak cengkeh, dan garam dalam transportasi tertutup ikan maanvis Pterophyllum scalare dengan kepadatan tinggi
Abstrak: Ornamental fish transportation was usually held at high density to efficient the transportation cost. Higher density of fish carried inside the container results on higher possibility of friction among fishes, causing fishes to wound and eventually die. This research was a continuation of the previous research’s result about 20 g/ℓ zeolite addition to 2 g weighed maanvish transportation at 20 fish/ℓ density, resulting on 100% SR at 120 hours transportation. Furthermore, a research about 10 g/ℓ zeolite and 10 g/ℓ activated carbon addition to 2 g weighed coridoras fish at 20 fish/ℓ density was able to maintain a 100% SR. Addition of supplement materials such as zeolite, active carbon, clove oil, and salt is necessary. These materials were aimed to raise and maintain water quality during the transportation process, so the highest density could be attained. The aim of this research was to evaluate efectiveness of zeolite, activated carbon, clove oil, and salt to mantain water quality on good condition during closed transportation system so can minimize the mortality rate of Maanvis which transported in 120 hours dan the mortality rate after transportation. Research phases was started from measuring the oxygen consumption rate, ammonia excretion, fish fasting ability, and tolerance test towards clove oil and salt optimum dosage. This research was held for 120 hours and 30 days post-transportation rearing. Survival rate of posttransportation with density treatment of 30, 40, 50, and 60 fish/ℓ was 84%; 93%; 87%; and 74% respectively. This research resulted that 40 fish/ℓ density treatment is more effective compared to other treatments with 93% SR and highest Specific Growth Rate, namely 0,91%, and the survival rate after transportation was 100%.
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Judul: Efektivitas penambahan zeolit 20g/ℓ, karbon aktif 10g/ℓ, dan garam dalam transportasi tertutup benih ikan gurame osphonemus gouramy Lac. dengan kepadatan tinggi
Abstrak: Fish transportation was usually held at high density to efficient the transportation cost, but Higher density of fish carried inside the container will be increase stress level of fish. Some stress will result in increased activity of fish physycology that could worst the water quality especially DO, CO2, and NH3. This research aimed to evaluate the effectifity of salt utilization in water transport media which had been given by zeolite and active carbon to maintain water quality of transport media, so the mortality during transportation of gouramy fish size ±4 cm can can be minimize during transportation. The research was conducted in laboratory scale with complete randome device. Gouramy fish Osprhonemus gouramy which use for this experiment were exsposed to five different doses and applied in two replications. Every treatment was describe A)blanko 50 fishes/ℓ (without zeolite, active carbon, and salt); B)control 50 fishes/ℓ + 20 g/ℓ zeolite + 10 g/ℓ active carbon; C) 50 fishes/ℓ + 20 g/ℓ zeolite + 10 g/ℓ actvive carbon, 1 g/ ℓ salt; D) 50 fishes/ℓ + 20 g/ℓ zeolite + 10 g/ℓ active carbon, 3 g/ℓ salt; and E) 50 fishes/ℓ + 20 g/ℓ zeolite + 10 g/ℓ active carbon, 5 g/ℓ salt. The package system was transported for 72 hour. Survival rate during transportation in every treatment A, B, C, D, and E was 0%, 57%, 59%, 65%, dan 74%. The result of this research showed that treatment E gave the best result seen from the survival rate (SR) with 74 %, associated with the transport medium water quality values had level of total amonia nitrogen (TAN) 1.619±0.28, NH3 0.069±0.016, DO 4,26 mg/ℓ and has the best specific growth rate 2.95%, and 100% of survival rate during post-transportation test.
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Judul: Invers dari Matriks Tridiagonal Jacobi
Abstrak: Suatu matriks berukuran n×n dinamakan matriks tridiagonal jika untuk . Karya ilmiah ini memberikan algoritma yang mudah untuk menemukan invers ( dari matriks tridiagonal Jacobi yang simetrik dan nonsimetrik. Setiap elemen pada matriks tridiagonal ini adalah bilangan real. Terdapat 3 lema dan 2 teorema untuk menentukan . Lema pertama menunjukkan persamaan utama dalam membuktikan lema-lema dan teorema-teorema selanjutnya. Invers dari matriks yang simetrik dibuktikan oleh lema kedua yang menunjukkan elemen-elemen baris ke- dari . Selanjutnya, lema kedua dilengkapi dengan teorema pertama yang menunjukkan elemen-elemen dengan . Invers dari matriks yang nonsimetrik dibuktikan oleh lema ketiga yang menunjukkan elemen-elemen dengan dan elemen-elemen dengan dibuktikankan oleh teorema kedua.
Keyword: symmetric, nonsymmetric, matrix