Judul: Proses Co-Composting Abu Ketel dengan Bagas menggunakan Kotoran Sapi dengan Perlakuan Laju Aerasi dan Nilai C/N Awal
Abstrak: Boiler ash and bagasse contain high organic carbon and have a good characteristic, so it facilitate the circulation and air flow went into co-composting. The objective of this research were to utilize solid waste of sugar cane industry, in the form of boiler ash and bagasse by composting (co-composting) with addition of cow dung, to understand the influence of aeration rate to the compossing process of bagasse and boiler ash, as well as the cow dung, to understand the influence of first C/N to the compossing process of bagasse and boiler ash from sugarcane industry and also the cow dung. In this research, to increase nitrogen value, it was added with the cow dung. The cow dung contained high N, P, and K as compost. Co-composting was done by aerated pile method and a passive aerated treatment defines as a control. The treatment was done with different composition of bagasse, boiler ash, and cow dung and the different aeration. The aeration was conducted in the rate 0.8 l/minute kg ingredient, 1.2 1/minute kg ingredients, and C/N formulation 30, 40, 50. Composting process was done in 42 days with active aeration in the first week. The analysis showed that aeration technique had no significant effect to change the C/N value. Generally, aeration factor had no different interaction, while the first C/N formulation had different results.
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Judul: Pengaruh Perbedaan Nilai C/N Dan Laju Aerasi Pada Proses Co-Composting Bagasse Dengan Blotong Pada Limbah Industri Gula
Abstrak: The sugarcane industry in Indonesia produce the waste from bagasse and filter cake that until recently is still not optimum in processing. One of alternatives handling is co-composting bagasse and filter cake that will produce compost and can reduce the amount of sugarcane industry wastes. This research aims to utilize bagasse and filter cake of sugarcane industrial waste for composting and aeration as well as differing effect of giving the C/N of the process. Composting methods used were aerated static pile technique and uses two factors of aeration and C/N ratio. Aeration was provided via active aeration (0,4 L/Kg of material and 1,2 L/kg material) and passive aeration with C/N respectively 30, 40, and 50. The composting process was running for a month with active aeration at first week. Analysis results show that aeration technique proved didn’t have significant effect in changing C/N value. After analysis, result shows that the most decrease C/N value is compost with starting condition 50 of C/N value. Generally, aeration factor are not related yet and do not have any significant interaction to co-composting C/N value.
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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