Judul: Perbaikan kualitas kompos tandan kosong kelapa sawit dengan penambahan abu boiler serta pengaruhnya terhadap sifat kimia podsolik merah kuning dan tanaman caisim (Brassica juncea)
Abstrak: Processing of oil palm fresh fruit bunch (FFB) to get crude palm oil (CPO) will produce some waste, among others is the oil palm empty fruit bunch (EFB). The EFB is abundantly produced in any plantations that without carefull handling will induce a problem to the environment. Some plantations have been using the EFB to produce compost. However, the quality of their compost from EFB is highly varies due to the use of different composting method. On the other hand, boiler ash of oil palm processing unit contains various and significance chemical elements that can be used to chemically improve the quality of EFB compost. This research was aimed to study: 1) the difference in quality of EFB composts produced by different composting methods, before and after addition of boiler ash, and 2) the influence of boiler ash-enriched EFB compost to chemical properties of Red Yellow Podzolic and mustard productivity. Each of EFB compost produced by opened method (K1) and by closed method (K2) were treated with four levels of boiler ash doses (A0 = 0%, A1 = 5%, A2 = 10%, and A3 = 15%). Both of materials are mixed and incubated for 2 weeks. Then boiler ash-enriched EFB compost were mixed with soil (compost : 20% and soil : 80% by volume) and used as medium to grow mustard in green house experiment. The experiment was designed in completely randomized design with 9 treatments and 3 replications. The treatments were comprise of control, K1A0, K1A1, K1A2, K1A3, K2A0, K2A1, K2A2 and K2A3. The results showed that the addition of boiler ash into EFB compost increased pH from 7,0 to 7,4-7,8 for K1 and from 7,6 to 7,7-7,8 for K2. The increase of compost pH was in accordance with the increase of boiler ash dose. Whereas macro and micro nutrients content was not influenced by the addition of boiler ash. Boiler ash-enriched EFB compost increased pH of Red Yellow Podzolic. K1 did not influenced C-organic, P-available, K-exchangeable, Ca-exchangeable and Mg-exchangeable content of Red Yellow Podzolic. In contrast, K2 increased P-available, K-exchangeable and Ca-exchangeable of Red Yellow Podzolic. Beside that, boiler ash-enriched EFB compost increased growth, yield and N, P, K, Ca, Mg content of mustard. The yield of mustard increased about 173,5% – 226,5% for K1 and 279% – 290% for K2 compared to control (68 g/plot).
Keyword: 

Judul: Composting of Palm Oil Midrib-leaf with Different Biodecomposter and used as Ameliorant
Abstrak: The number of palm oil midrib-leaf wastes generated is increasing in line with the growth of palm oil production. Midrib buildup on the sidelines of palm oil plantations, especially in side off lines on several palm oil estates has the potential to become a den / host for pests and diseases. Palm oil midrib-leaf contains high lignin and cellulose that requires a long time to be able to decompose completely. Efforts to speed up and maximize the composting palm oil midrib-leaf waste with using biodecomposter expected to minimize organic matter transported from the field at harvest time. Trimming leaves can even be returned to the field in the form of materials ready used to maintain the stability of soil organic matter after going through the process of decomposition. The objective of study were to identify indigenous microbe isolates, to compare the rate of composting and to identify influence of using compost toward growth and caisin yield (Brassica rapa). This experiment was done in Laboratory of Soil Biotechnology, Department of Soil Science and Land Resources and Cikabayan Teaching Farm in IPB Dramaga Bogor. Microbe identification was held in IPB Culture Collection (IPBCC). Analysis of soil nutrients and compost materials were conducted at the Laboratory of Soil Fertility, Soil Science and Land Resources Department. Chlorophyll analysis was done in the Laboratory of Molecular Marker Spectrophotometry and stomatal observation was carried out at the Microtechnic Laboratory of Agronomy and Horticulture Department (AGH). Stages of the study were lasted from October 2012 to August 2013. This study consisted of three experiments. The first, microbe exploration was used as biodecomposter. The results obtained show that indigenous biodecomposter produce the number of colonies twice more than commercial biodecomposter. According to identification result, indigenous microbe derived from the natural weathering of oil palm estate is a type of fungi Trichoderma asperellum. The second, composting of palm oil midrib-leaf. Treatment 1 (B0) shredded palm oil midrib-leaf + cow manure by 10%; treatment 2 (B1) shredded palm oil midrib-leaf + cow manure by 10% + commercial biodecomposter; treatment 3 (B2) shredded palm oil midrib-leaf + cow manure by 10% + indigenous biodecomposter. The experimental design used was one factor Randomized Block Design (RBD) with 3 treatment levels. Based on the variables observed like temperature, the ratio C / N, the degree of acidity (pH), volume shrinkage, the physical condition of the compost materials and compost nutrient analysis show that the rate of composting of indigenous biodecomposter is higher than commercial biodecomposter up to 8 weeks after application of biodecomposter. This indicates that the treatment of indigenous biodecomposter is more effective than commercial biodecomposter, because cellulose destroyer microbial isolates which is in it comes from the same environment with the composted material. The third experiment, the compost use produced as organic caisin ameliorant. There are four media treatments namely M0 (soil media without compost); M1 (soil media + compost B0 without biodecomposter); M2 (soil media + compost B1 with indigenous biodecomposter); M3 (soil media + compost B2 with commercial biodecomposter). Composts derived from palm oil midribleaf waste which had been composted with
Keyword: 

Judul: igenvalues and Eigenvectors of Tridiagonal Matrix with Non Constant and Recurrent Diagonal Entries.
Abstrak: Matriks tridiagonal adalah suatu matriks yang mempunyai entri-entri bernilai nol kecuali pada diagonal utama, di bawah diagonal utama (subdiagonal) dan di atas diagonal utama (superdiagonal). Entri pada diagonal utama tidak konstan dan berulang. Setiap entri pada matriks tridiagonal ini adalah bilangan kompleks. Dalam karya ilmiah ini, akan dibuktikan 3 teorema untuk menentukan nilai eigen dengan 2 kasus dan 1 teorema untuk menentukan vektor eigen. Teorema pertama menentukan polinomial karakteristik dari matriks tridiagonal. Polinomial karakteristik dari matriks tridiagonal tersebut digunakan untuk menentukan nilai eigen pada teorema kedua dan ketiga serta menentukan vektor eigen pada teorema keempat
Keyword: