Judul: The potency of sago waste as ameliorant and bio-herbicide on bushy pepper crop
Abstrak: Sago processing produces sago waste that further can be used as a source of organic matters. About 75% of the sago by product are barks and sago waste that so far has not been used, but it potentially can be utilized as ameliorant and bioherbicide
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Judul: Role of planting a d return of companion crops, biomass of yam bean and centrowma and N, P, K, Mg fertilizers application in bushy black pepper culture
Abstrak: Study result revealed that bushy black pepper belongs to 'luxury plan?' that it consumes nutrients in a large number. This condition accelerated the degradation of land, reduction of productivity and aggravation the environment. Soil amelioration wuld be done by application of organic matter. In srtu prduaion of organic matter is one kind of the solution. The objechves of rhr: study were; (1) testing of yam bean and centrosema as companion crops on bush pepper plantation and iis effect on pepper production, (2) testing of organic matter from yam bean and centrosema, and application of N, P, K, Mg fertilizer on the growth, production, physiologcal traits, quality of black pepper, soil micraclimate and soil properties, and {3) obtaining the optimum dosage of inorganic fertilizer combined wit11 orpic matter, as well as the information on reducing inorganic fertilizer requirement by application of orgaiic ma-. To achieve the objectives, two studia were done; (1 ) e m of yam bean and mtrosema on the growth and production of bushy black pepper, and (2) effect of biomass re-1 of yam bean and centrosema and dosage of inorgamc f* of N, P, K, Mg on tbe growth and yield of bushy black pepper. Result of the studies showed that planting of yam b n and centrosema as cumpaion mops improved the vegetative and p d v e growth of bushy black psppr, as well as i n c d the yield, chlorophyll content, plant nutrient status, and improved thg biologicat, physical, a d chemid properties of the soil. Application of organic matter and inorganic fertilizer, aside improved the former parameters, also inatwed the quality of black pepper. The optmum level of inorganic Edizer is 389.71 glplant for pepper monoculture system, 235.28 giplant for pepper - yarn bean system and 200.9 1 @plant for pepper - centrosema system. The optimum level of inorganic fertilizer is 330.32 @plant for pepper system without green manure appbtion, 186.79 @plant for pepper mulch system and 158.98 glplaat for peppa system with incarpration of gmm manure into the soil. Based on the result of both studies, it could be umcluded that planting yam bean arad centrogema as companion crop on b w blsbclr pepper phmion, and inmqmmion return of piant's biomass is one way to increase pepper production as well as improved soil promes.
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Judul: Invers dari Matriks Tridiagonal Jacobi
Abstrak: Suatu matriks berukuran n×n dinamakan matriks tridiagonal jika untuk . Karya ilmiah ini memberikan algoritma yang mudah untuk menemukan invers ( dari matriks tridiagonal Jacobi yang simetrik dan nonsimetrik. Setiap elemen pada matriks tridiagonal ini adalah bilangan real. Terdapat 3 lema dan 2 teorema untuk menentukan . Lema pertama menunjukkan persamaan utama dalam membuktikan lema-lema dan teorema-teorema selanjutnya. Invers dari matriks yang simetrik dibuktikan oleh lema kedua yang menunjukkan elemen-elemen baris ke- dari . Selanjutnya, lema kedua dilengkapi dengan teorema pertama yang menunjukkan elemen-elemen dengan . Invers dari matriks yang nonsimetrik dibuktikan oleh lema ketiga yang menunjukkan elemen-elemen dengan dan elemen-elemen dengan dibuktikankan oleh teorema kedua.
Keyword: symmetric, nonsymmetric, matrix