Judul: Analisis Biaya Produksi Grease Proof Board (Studi Kasus PT Indah Kiat Pulp and Paper, Serang Mill)
Abstrak: Perkembangan industri kertas di Indonesia sejalan dengan permintaan terhadap kertas. Saat ini selain untuk kebutuhan dalam negeri, industri kertas di Indonesia juga memenuhi permintaan pasar luar negeri. Namun pada kenyataannya pasokan bahan baku masih terbatas dan produksi belum dapat mengimbangi permintaan yang semakin tinggi sehingga industri pulp dan kertas di Indonesia belum memiliki daya saing yang kuat dengan industri pulp dan kertas di luar negeri. oleh karena itu peningkatan produksi dan daya saing harus dilakukan Industri pulp dan kertas di Indonesia, sehingga untuk mencapai target tersebut perlu adanya perencanaan biaya produksi yang matang untuk dapat menghasilkan profitabilitas produksi yang tinggi. Penelitian analisis biaya produksi Grease Proof Board dilakukan di PT Indah Kiat Pulp and Paper, salah satu perusahaan kertas terbesar di Indonesia.Hasil penelitian menunjukkan bahwa biaya produksi rata-rata untuk Grease Proof Board adalah US$ 694,54/ton, yang terdiri dari biaya tetap dengan rata-rata sebesar US$ 146,62/ton dan biaya variabel dengan rata-rata sebesar US$ 547,92/ton dengan produksi rata-rata sebesar 1.650 ton/bulan. Hasil perhitungan yang telah dilakukan didapat bahwa nilai Break Even Point sebesar 807,23 ton/bulan, sedangkan nilai ROI perusahaan sebesar 16,80% dan harga pokok sebesar US$ 833,44/ton.
Keyword: biaya produksi, harga pokok, profitabilitas, grease proof board, pulp, kertas

Judul: Analisis Biaya Produksi Carbonless Copy Paper (Studi Kasus di PT. Pindo Deli Pulp and Paper Mills II).
Abstrak: The usage of papers domestically and internationally has risen every year, along with the development of world population results in the demand of paper to continuously increasing. To increase competitiveness, there needs to be regulations and good surveillance in the production activities. Analysis of production cost is one way that can be done in order to determine the most effective and efficient production process, so that hopefully pulp will be able to be produced with minimum cost and without negativelyaffecting the quality of the product itself. This paper cost analysis research is done in the department of Non- Carbon Required PT.Pindo Deli Pulp and Paper; this particular company is one of the most renowned paper production company in Indonesia. The result of this research shows that, on average, the production cost of Carbonless Copy Paper is US$1.332,26/ton, where as this value itself consists of average fix cost which is US$ 209,74/ton and average variable cost which is US$ 1.122,5/ton. The average production is 6.646,89 ton/month. The results of the calculation shows that the value of breakeven point is 2.919,75 ton/month. The ROI acquired from this company is equal to 21.36%, furthermore the basic price is valued at US$ 1.665,32/ton
Keyword: pulp and Paper., carbonless copy paper, profitability, Bogor Agricultural University (IPB), basic price, production cost

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model