94 articles for “block-by-block method”

Research ArticleOpen accessIn the abstractEffect of Mixing Urea with Humic Acid and Acid Sulphate Soil on Ammonia Loss, Exchangeable Ammonium and Available NitrateMohd Taufik Mohd Yusuff, Osumanu Haruna Ahmed, Nik Muhamad Ab MajidProblem statement: Ammonia loss due to rapid hydrolysis of urea in soil following surface application can be substantial. Ammonia loss in agriculture is estimated to be 1 to 60%. This laboratory study compared the effect of three different urea-humic acid-acid sulphate soil mixtures on NH3 loss and soil ammonium and nitrate contents, with loss from surface applied urea without additives … …American Journal of Environmental Sciences, Vol. 5, Issue 5 · 31 Oct 2009 · 8,906 accessesView PDF Cite

Research ArticleOpen accessAll words, across the recordKey Based Random Permutation (KBRP)Shakir M. Hussain, Naim M. AjlouniThis study introduces a method for generating a particular permutation P of a given size N out of N! permutations from a given key. This method computes a unique permutation for a specific size since it takes the same key; therefore, the same permutation can be computed each time the same key and size are applied. The name of random … …Journal of Computer Science, Vol. 2, Issue 5 · 31 May 2006 · 7,366 accessesView PDF Cite

Research ArticleOpen accessAll words, across the recordA Comparative Study of Block Preconditioners for Incompressible Flow ProblemsJia LiuProblem statement: We consider the numerical solvers for the linearized Navier-Stokes problem. Both the Stokes problem and Oseen problems are considered. Approach: We used the Mark and Cell (MAC) discretization method to discretize the Navier-Stokes equations. We used preconditioned Krylov subspace methods to solve the resulting linear systems. Results: Numerical experimental results are performed to compare the different preconditioners. Conclusion: … …Journal of Mathematics and Statistics, Vol. 7, Issue 4 · 14 Sep 2011 · 7,063 accessesView PDF Cite

Research ArticleOpen accessAll words, across the recordSimulation Model of Brushless Excitation SystemAhmed N. Abd AllaExcitation system is key element in the dynamic performance of electric power systems, accurate excitation models are of great importance in simulating and investigating the power system transient phenomena. Parameter identification of the Brushless excitation system was presented. First a block diagram for the EXS parameter was proposed based on the documents and maps in the power station. To identify … …American Journal of Applied Sciences, Vol. 4, Issue 12 · 31 Dec 2007 · 7,522 accessesView PDF Cite