Judul: Solusi Numerik Masalah Kontrol Optimum Penyebaran Penyakit Influenza A
Abstrak: Influenza A is an acute respiratory disease caused by a virus H1N1. The virus is mainly transmitted by air and can be contagious from human to human. In this work, a mathematical model of SIR is used to describe the disease transmission, where the population is divided into three classes namely susceptible, infected, and recovered. Analysis was performed on two cases, those are models without and with control, i.e. vaccination treatments. The model of H1N1 transmission is applied at regency and city of Bogor with a total population of six million people. Model without control provides two equilibrium points, where from stability threshold for disease free equilibrium point is obtained a basic reproductive number . The disease will die out if and may become endemic if . On the model with administration of control we minimized the infected population and the vaccination cost. Numerical solutions of nonlinear system of differential equations derived from the conditions of Pontryagin minimum principle are conducted by Runge-Kutta 4th order method. The results of numerical simulation show that the model without control administration, basic reproductive number causes more infected individuals than that of . Meanwhile, the effect of the treatment above decreased the number of H1N1 infected down to .
Keyword: Runge-Kutta 4th order, Pontryagin minimum principle, optimal control, influenza A (H1N1), stability analysis

Judul: Kontrol Optimum Vaksinasi dan Pengobatan pada Penyakit Menular Tipe SIR
Abstrak: Nowadays, there are many infectious diseases that cause epidemic in the population. Therefore, an effective program is required to eliminate the infectious diseases, such as vaccination and treatment. The spread of infectious diseases can be modeled by SIR model, in which it enables us to predict the outbreak and the control rate. In this research, the SIR model is applied to analyze the population dynamic and to optimize the control of the outbreak with vaccination and treatment. As the result, the model provides two equilibrium points, i.e. dieasesfree and diseases-endemic equilibrium points. Moreover, the analysis show that if the reproduction number or ℛ0 is less than or equal 1, then the disease-free equilibrium point is globally asymptotically stable. While if ℛ0 is more than 1, then the disease-endemic equilibrium point is globally asymptotically stable. In this research the optimal control uses Pontryagin’s minimum principle with vaccination and treatment as control measures. The control objective is to find the optimal combination of vaccination and treatment that minimizes the cost of the two control measures as well as the number of infected individuals at the end of control period.
Keyword: vaccination., treatment, SIR model, Pontryagin’s minimum principle, optimal control

Judul: Karakteristik Komponen Kayu Bagian Lunas, Gading-gading, dan Linggi pada Kapal Kayu di Teluk Nara, Lombok Utara
Abstrak: Kapal SV Vivian merupakan kapal pariwisata yang terbuat dari kayu solid. Kapal SV Vivian terdiri dari bagian lunas, linggi haluan dan linggi buritan, gading-gading, wrang, galar kim, galar balok, balok geladak dan lutut-lutut, kulit luar, geladak, pagar, sekat kedap air. Pembuatan kapal hanya didasarkan pada pengalaman, sehingga perlu diteliti untuk mengetahui karakteristik komponen kayu yang digunakan. Penelitian mengukur karakteristik atau sifat-sifat dasar komponen kayu yang digunakan pada bagian gading-gading, linggi dan lunas. Standar pengujian yang digunakan yaitu BS-373: 1957. Jenis kayu yang digunakan untuk pembuatan lunas dan linggi yaitu kayu Ulin (Eusideroxylon zwageri) dan gading-gading menggunkan kayu kempas (Koompasia malacensis). Kayu ulin memiliki karakteristik yang lebih baik dibandingkan dengan kayu kempas. Kayu ulin masuk kedalam kelas kuat I dan tahan terhadap serangan marine borers sehingga tergolong kedalam kelas awet I. Kempas tergolong kedalam kayu dengan kelas kuat II dan ketahanan terhadap marine borers masuk kedalam kelas awet V. Bagian lunas kapal disambung dengan menggunakan baut dan jenis sambungan yang digunakan yaitu plain scarf.
Keyword: Lunas, Gading-gading, Linggi, Sifat Fisis, Sifat Mekanis