Judul: Efisiensi Pemanfaatan Bahan Baku Kayu Lapis Di PT. Kutai Timber Indonesia, Probolinggo-Jawa Timur
Abstrak: Raw material efficiency utilization is one of a success indicator that measures the plywood industry performance by which production units are evaluated. Raw materials efficiency utilization is a simple way to measure the level of competitiveness and effective usage of wood raw material. By increasing the efficiency, the industry can reduce the resulted waste. The purpose of this research is to find out the efficiency of wood raw materials utilization in plywood production process in PT. Kutai Timber Indonesia. The conclusions of the research results are as follows: (1) The average efficiency level of wood raw material utilization at PT. Kutai Timber Indonesia in 2011-2013 was 53.40% per year. (2) The most inefficiency step process was arranging core veneer as reflected by the average highest waste volume (13.37%). (3) PT Kutai Timber Indonesia failed to meet the efficient plywood industry according to Ministry of Forestry Regulation No. P.17/Menhut-II/2004 regarding Standard Operation procedure for Primary Forest Products Industries Efficiency Evaluation. (4) In order to increase the level of wood raw material utilization, PT. Kutai Timber Indonesia use most of the wood waste resulted from the plywood industry for wood pellet, particleboard, wood working and boiler raw material
Keyword: PT. KTI, Raw Material, Plywood, Efficiency

Judul: Pengendalian Bahan Baku Industri Kayu Lapis: Studi Kasus di PT. Kutai Timber Indonesia, Probolinggo, Jawa Timur
Abstrak: Kayu lapis merupakan salah satu produk kayu yang paling sering digunakan dan merupakan penghasil devisa terbesar kedua setelah pulp untuk kelompok industri pengolahan kayu. Tujuan penelitian ini adalah mengidentifikasi, menginvestigasi berbagai teknik MRP, dan membandingkannya dengan sistem perusahaan. Sistem pengendalian persediaan bahan baku kayu lapis PT. Kutai Timber Indonesia dilakukan dengan basis teknik lot for lot (LFL) disertai safety stock untuk menghindari stock out. Semua teknik MRP menghasilkan biaya persediaan yang lebih kecil dibanding dengan metode perusahaan. Secara keseluruhan teknik LUC merupakan teknik terbaik untuk menghemat biaya persediaan bahan baku kayu lapis PT. KTI untuk periode tahun 2011-2015.
Keyword: forecasting, inventory, material requirements planning (MRP), plywood, raw materials

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