Judul: The study of aeration effect and sludge concentration to decrease rate of c/n value from co-composting process of filter cake and sludge of the sugar industry
Abstrak: Filter cake and sludge are a solid waste of sugar industry which containing high organic material so that can be used as raw material for making organic fertilizer. Technology co-composting can reduce the content of organic material with the help of microorganisms decomposing. The purpose of this research is utilizing blotong and sludge of the sugar industry through co-composting technology and determine the influence of aeration and sludge concentration on the value of C / N in the co-composting and sludge blotong sugar industry. The research were done by the air stream both actively and passively on filter cake and sludge mixture. The active aeration treatment conducted during the first week so it can help the process of decompotition of organic material. Filter cake and sludge mixture consisting of three standard sludge concentration is 0%, 15, and 30%. Co-composting technology can be used as an alternative solid waste handling of the sugar industry. Aeration treatment and variated concentration of sludge did not give a noticeable effect on the value of C / N. The aeration rate of 2 L / kg dry basis and time of aerating did not affect the process of decomposition of organic material.
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Judul: Co-composting bagasse with sludge sugar industry waste using aeration techniques and its effect in value of c/n
Abstrak: Bagasse is the solid waste sugar industry and relatively abundant (30-40%). Sugarcane planted area in Indonesia reaches 395,399.44 hectare and potentially to achieve national bagasse 39,539,944 tons per year. As well as produced sludge each day around 10-50 %. Sludge has quite high carbon content and nitrogen, thus potentially to be composting. Co-composting is one of the alternative solutions in the utilization of industrial solid waste of sugar. One of them is the bagasse and sludge with complementary characteristics, thus simplifying the process of composting. Composting methods and that techniques applied are aerated static pile system and using two factorial of aeration and formulation. Aeration factor conducted by active and passive aeration, while the formulation conducted by a factor of 0%, 25%, and 50% sludge. Composting process carried out during the sixty days with active aeration at first week. Analysis results showed that aeration technique proved didn’t have significant effect in changing C/N value. After analysis of variance and advanced test showed that the formulation of three different stages proved significantly different of C/N and significant at 50% sludge. Generally, aeration factor and formulation are not related yet and do not have any significant interaction to co-composting C/N value. There is need for advanced research until the value of C/N can achieve the appropriate standard of quality compost.
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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