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: Proses Co-composting Bagas dan Sludge dari Industri Gula dengan Pengaruh Perbedaan Nilai C/N Awal dan Aerasi
Abstrak: Bagasse and sludge are solid waste of sugar industry which contained high organic material and have not been used optimally. The purpose of this research was to utilize bagas and sludge of the sugar industry through co-composting technology for making organic fertilizer and determine the influence of aeration and materials concentration on the value of C/N. Bagas and sludge combination were composted at C/N value of 30, 40, and 50. In composting process, aeration rate set on 0.4 l/minute.kg and 1.2 L/Kg of dry basis materials. The research was carried out two stages, that was preliminary research, it was determined composition of raw materials mixture, and primary research for determining C/N value during composting. Parameters monitored during composting were temperature done every day, pH and C/N determined every week. The result showed that aeration treatment did not give noticeable effect on C/N value and compost with initial C/N value of 30 gave the fastest decomposition process in co-composting stages
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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