Judul: Pengaruh Pupuk Organik Guano dan Chitosan terhadap Pertumbuhan dan Perkembangan Anggrek Phalaenopsis spp.
Abstrak: This research was conducted to determine the effect of organic fertilizer guano and chitosan on the growth and development of phalaenopsis orchid conducted in the Gunung Batu nursery, Bogor in March until August 2011. This research used a completely randomized block design with 4 treatments and 4 replications. Fertilizer treatments consisted of Thaichung fertilizer 1 g /l, Thaichung fertilizer 1 g/l + chitosan 10 ppm, Thaichung fertilizer 1 g/l + guano 10 ml / l, and Thaichung fertilizer 1 g/l + chitosan 10 ppm + guano 10 ml / l. Thaichung fertilizer 1 g/l were needed for P. bellina and P. modesta, and guano 10 ml/l were needed for P. amabilis in compot in the hot and dry conditions.
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Judul: Pengaruh Bahan Organik Chitosan dan Pupuk Guano terhadap Pertumbuhan dan Perkembangan Anggrek Dendrobium ‘Woxinia’.
Abstrak: The purpose of this research was to study the effect of organic matter chitosan and fertilizer guano on the growth and development of the orchid Dendrobium 'Woxinia'. The experiment took place at the University Farm Green House, Cikabayan. The study lasted from February to August 2011. This study used a randomized design Completly Group with two factors with the first factor is the concentration of chitosan consisted of three levels of 0, 10 and 20 ppm/ plant. The second factor is the concentration of guano fertilizer with 3 levels of 0, 10 and 20 ml / l water. Observations performed every single week for 5 months. The result showed that treatment with 10 ppm chitosan gave is significantly increased the number of pseudobulb (1.4). Guano 10 ml/l increased plant height at 10-19 Weeks After Treatment (WAT) (23.64 cm average an 19 WAT). At 9 Weeks After Treatment (WAT), leaf length at 9 Weeks After Treatment.
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Judul: Invers Drazin dari Matriks Toeplitz Singular
Abstrak: Matriks Toeplitz adalah matriks yang setiap unsur pada diagonal utama bernilai sama dan setiap unsur pada subdiagonal yang bersesuaian dengan diagonal utama juga bernilai sama. Matriks singular adalah matriks yang tidak bisa ditentukan inversnya. Akan tetapi, dapat diupayakan untuk ditentukan inversnya menggunakan invers matriks yang diperumum. Invers Drazin merupakan salah satu jenis invers matriks yang diperumum. Pada karya ilmiah ini ditentukan invers Drazin dari matriks Toeplitz singular dengan menggunakan metode Leverrier Faddeev. Kemudian, ditentukan invers Drazin dari matriks Toeplitz singular yang direpresentasikan sebagai penjumlahan segitiga bawah dan segitiga atas matriks Toeplitz berdasar pada teorema Gohberg dan Semencul., Toeplitz matrix is a matrix in with element on the main diagonal has the same value and on the subdiagonal corresponding to the main diagonal also has the same value. Singular matrix is a matrix that has no inverse. However, it can be attempted to determine the inverse using a generalized inverse matrix. Inverse Drazin is a type of generalized matrix inverse. This paper discussed the inverse Drazin for a singular Toeplitz matrix using the Leverrier Faddeev method. Then, the Drazin inverse of the singular Toeplitz matrix which is represented as a sum of products of lower and upper triangular Toeplitz matrix based on Gohberg and Semencul theorem.
Keyword: inverse Drazine, singular Toeplitz matrix