Judul: Kajian Pengurangan Pemborosan Proses Produksi Kemasan Karton Bergelombang dengan Lean Six Sigma di PT Dayacipta Kemasindo Plant Karawang.
Abstrak: PT Dayacipta Kemasindo Plant Karawang merupakan salah satu perusahaan yang memproduksi karton bergelombang. Perusahaan tersebut menghadapi permasalahan pemborosan berupa waktu menunggu, gerakan yang tidak diperlukan, dan produk cacat khususnya produk XYZ. Lean Six Sigma dapat digunakan sebagai pendekatan yang sistematis untuk mengurangi pemborosan tersebut. Penelitian ini bertujuan untuk mengidentifikasi jenis dan penyebab pemborosan pada proses produksi dan menganalisis pengurangan pemborosan dengan Lean Six Sigma di perusahaan tersebut. Metode penelitian menggunakan metode Define, Measure, Analyze, Improve, Control (DMAIC) yang divisualisasikan dengan Value Stream Mapping kemudian ditelusuri akar masalahnya menggunakan Root Cause Analysis berupa diagram fishbone. Hasil usulan perbaikan menunjukkan pengurangan aktivitas Necessary but Non Value Added (NNVA) dari 24.22 menjadi 6.22 jam, aktivitas Non Value Added (NVA) dari 21.73 jam menjadi 6.00 jam. Pengurangan masing-masing aktivitas dapat meningkatkan nilai Process Cycle Efficiency (PCE) dari 4.27% menjadi 9.48%, dan peningkatan nilai sigma dari 3.95 menjadi 4.20.
Keyword: lean six sigma, metode DMAIC, pemborosan, value stream mapping

Judul: Analisis Pengurangan Jumlah Produk Cacat pada Industri Kertas dengan Pendekatan Lean Six Sigma
Abstrak: The high number of the defective product that occur in each company can affect quality. PT. X is a company engaged in the pulp and paper product. Lean approach does not allow for waste, in this case, defective product. Product defects that often arise in this industry are paper holes, dirty paper, folded, size variations and foreign contamination. The purpose of this study is to identify the causal factors in the production line of a product defect based on six sigma stages. The solution that can reduce the number of defects. The stages of six sigma are define, measure, analyze, improvement and control. The results of calculation of the value sigma of paper holes for two months was 4.66 and 4.58. Dirty paper has a sigma value of 4.99 and 5.06. The sigma level indicates that the performance of the production is above average Indonesian company. The costumer complaint coming into the company for folded paper, size variations and foreign contamination has decreased from 2010 to 2011. But it has not reached the six sigma target. Therefore, the company needs to be improved using the Lean tool, that is Kaizen Blitz.
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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