Judul: The Application of Homotopy Perturbation Method to Solve Nutrition Recycle Problems
Abstrak: Ecosystem is an ecological system that is formed by a mutual inseparable relationship between living organism and environment. The interaction among the components within an ecosystem, especially the nutrition recycle, can be modeled by using mathematical equation. The nutrition recycle model can be classified as a nonlinear problem. This phenomenon can be best represented by homotopy perturbation method. Homotopy perturbation method is defined as an analytical approach to solve a nonlinear problem. Based on this method, it can be concluded that the solution of nutrition recycle problem has a form of power series. By using MATHEMATICA software, it has been shown that the higher order of series used, the better model can be obtained. The model is expected to resemble the real solution. If the growth rate of autotroph is higher than its mortality rate, then the amount of abiotic nutrition and detritus organism will be declining, but the number of autotroph will increase. In the case rate of equal growth and mortality rate of autotroph, it will result into a decrease in abiotic nutrition, detritus organism, and autotroph number.
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Judul: Penggunaan Metode Homotopi Pade' untuk Menyelesaikan Masalah Lotka–Volterra Logistik.
Abstrak: In this research, the problems of Lotka–Volterra and Lotka–Volterra with prey logistic growth models are solved by using homotopy and Pade' homotopy methods. The homotopy method is an analytical approach to solve non linear problems. The solution of homotopy method is common series. The solution of the problem using Pade' homotopy method is obtained by using the result of applying the homotopy method and then transforming the equation into the form of rational function. The results of homotopy and Pade' homotopy methods are compared with some numerical solutions. The result shows that in solving Lotka–Volterra and Lotka–Volterra with prey logistic growth, the Pade' homotopy method is better than homotopy method because the Pade' homotopy method covers a larger area of convergence and produces smaller errors.
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Judul: Infeksi Virus Parainfluenza Pada Anjing
Abstrak: Virus parainfluenza anjing termasuk famili Paramyxoviridae, berbentuk pleomorf dengan ukuran bervariasi (bergaris tengah antara 100-500 nm), berpembungkus peka ether, berisi genom RNA dan secara serologis mempunyai kesamaan dengan virus SV-5 kera; dikenak sebagai salah satu kausa penting dari sindrom "kennel cough". Infeksinya dapat mengenai anjing semua umur yang belum pernah terinfeksi atau mendapatkan vaksinasi mengakibatkan gejala klinis ringan yang terbatas pada traktus respirasi atu infeksi yang secara klinis tidak memperlihatkan gejala nyata. Gejala klinis yang nampak setelah masa inkubasi (1-5 hari) terlewati berupa batuk yang tidak berat selama beberapa hari, berbagai tingkat tonsilitis dan pharyngitis dan kadang-kadang ditemukan kenaikan temperatur rektal antara 1-2 derajat C dari temperatur normal rat-rata. Anjing terinfeksi mengandung virus pada traktus respirasi bagian atas dan bawah serta limfonoduli sampai hari ke 9 setelah infeksi. Penyebaran virus antar anjing terjadi secara aerogen.
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