Judul: Analysis of Spatio Temporal Dynamics Model in Malaria
Abstrak: Malaria is an infectious disease caused by protozoa of the genus Plasmodium, which is transmitted from person to another person through the bites of female Anopheles mosquitoes. Mathematical model can be used to study the spread of the disease. The mathematical model discussed in this paper is Ross- MacDonald model and models with spatial heterogeneity of migration model and visitation model. For the models of heterogeneous environments with mobility, we also made numerical simulations for different values of intensity connection between patches, values of e (the proportion of humans migrate) and T (visitation time). Stability analysis of Ross-MacDonald model give two stable equilibrium points. For the migration and visitation models, there are four stable equilibrium points. When in a fragmented environment, humans have a high migration rate between patches, the system will more rapidly reach the same equilibrium prevalence it reached with lower migration rates. When humans visit other patches, an increase in the time devoted to the visits will make the system reach a higher equilibrium prevalence more rapidly. The numerical simulation show that increasing mosquitoes mortality rate makes the number of infected humans being exposed decrease. If average bite of an infected mosquito increases, then the number of infected humans who become exposed also increases. For the mosquito population, increasing mosquitoes mortality rate will cause the number of infected mosquitoes being exposed decrease. Increasing the average bite of an infected mosquito will increase the number of infected mosquitoes that become exposed.
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Judul: Dinamika populasi manusia dan vektor pada penularan penyakit malaria oleh plasmodium falciparum dan plasmodium vivax
Abstrak: Malaria is a disease that transmitted to human by the bitting of infectious Anopheles mosquitoes. This infectious desease caused by parasite genus Plasmodium. There are two species of the parasites studied here, that cause human malaria namely Plasmodium vivax and Plasmodium falciparum. The mathematical model in discribing the transmission of Plasmodium falciparum and Plasmodium vivax on human population is divided into four classes, the susceptible, the infectious, the dormant, and the recovered classes. Mosquitoes that caused malaria are called the vector. In this case, the vector population is divided into two classes, the susceptible and infectious classes. There are two equilibrium states, a disease free state E0 and an endemic state E1. The stability of E0 and E1 is determined by considering the basic reproductive number (R0). The E0 is stable if R0 is less than one. On the other hand, the point E1 was stable given the value of R0 is greater than one. In this research the dynamic of human population and vector is discribed in to some ilustrative sample with 5% and 50% of the infected vector. It is found that, if R0 < 1, with 5% infected vector could reach the stability faster than the 50% infected vector. For R0 > 1 , it was found that, 5% infected vector could reach the stability slower than the 50% infected vector. This research also showed that the interaction between susceptibles and infectious human has no effect in to the dynamic of the human population.
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Judul: Pembuatan papan semen dari sabut kelapa, Cocos nucifera L.
Abstrak: Di Indonesia, terutama di daerah sentra kelapa, tempurung dan sabut hanya digunakan sebagai bahan bakar, bahan kerajinan, dan sebagian kecil diolah menjadi arang. Menurut penelitian sebelumnya (Masri 1998), sabut kelapa memiliki potensi untuk digunakan sebagai bahan dasar papan semen, meskipun papan yang dihasilkan pada penelitian ini belum dapat memenuhi standar JIS A 5417 – 1992, terutama pada sifat mekanisnya. Penelitian ini bertujuan untuk mempelajari pengaruh penggunaan serat sabut kelapa sebagai bahan baku papan semen, serta pengaruh peningkatan taraf semen dan penambahan accelerator CaCl2 terhadap kualitas papan semen.
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