Judul: Design of a Dryer in UPLCT
Abstrak: Rajungan merupakan komoditas hasil laut yang memiliki nilai ekonomi tinggi di Indonesia dengan kapasitas produksi 47.895 kg/hari, sehingga ada potensi limbah cangkang sebanyak 25.187 kg/hari yang tersebar di pesisir Indonesia. Hal ini menunjukkan adanya potensi terkait peningkatan nilai tambah limbah cangkang rajungan. Permasalahan yang terjadi adalah cangkang yang tersebar, jumlahnya beragam, dan menimbulkan bau akibat pengeringannya yang tidak efisien. Dalam meningkatkan nilai tambah limbah cangkang rajungan membutuhkan unit pengelolaan limbah cangkang terpadu (UPLCT) yang dapat mengeringkan cangkang dengan kualitas yang sesuai dengan kebutuhan industri pengolah cangkang. Proyek ini bertujuan mendesain alat pengering yang efisien dan ekonomis, memiliki kapasitas yang memadai, menghasilkan kualitas cangkang yang sesuai, mudah dioperasikan, serta mengurangi pencemaran lingkungan. Jenis pengering yang dipilih menggunakan matahari karena dapat menghemat biaya, kualitas yang dihasilkan sesuai (tersortir dengan kadar air < 16 %), mudah dioperasikan, dan dapat mengurangi pencemaran. Alat pengering ini memiliki kapasitas 270 kg/alat dengan dimensi (4,15 x 2,15 x 1,61) m dan lama waktu pengeringan 6,2 jam. Hasil validasi prototipe menunjukkan bahwa desain alat pengering yang diberikan diterima oleh mitra (APRI), pemangku kepentingan dan dapat menjawab permasalahan yang ada., Blue swimming crab is a marine product commodity that has high economic value in Indonesia with a capacity of 47,895 kg/day, so there is a potential for shell waste of 25,187 kg/day scattered on the coasts of Indonesia. This indicates the potential for increasing the added value of crab shell waste. The existing problem are shells that are scattered, have various capacities, and inefficient drying. In order to increase the added value of crab shell waste, an UPLCT is needed which can dry the shells to the specifications desired by the shell processing industry. This project aims to design a dryer that is efficient and cost-effective, has sufficient capacity, produces appropriate shell quality, has an easy process, and reduces environmental pollution. Solar drying was chosen as the drying method because it can save costs, the quality produced is appropriate (sorted with a moisture content <16%), easy to operate, and can reduce pollution. This dryer has a capacity of 270 kg per unit with dimensions (4.15 x 2.15 x 1.61) m and a drying time of 6.2 hours. The prototype validation results show that the dryer design provided is accepted by partners (APRI), stakeholders and can answer existing problems.
Keyword: crab shells, drying, solar drying

Judul: Business Model Design and Financial Feasibility Analysis for UPLCT
Abstrak: Rajungan merupakan salah satu komoditas hasil laut yang memiliki potensi pengolahan yang besar dari hasil daging dan cangkangnya. Pemanfaatan cangkang atau limbah padat rajungan dapat diolah menjadi berbagai jenis produk dengan nilai tambahnya yang berbeda-beda. Limbah padat yang dihasilkan dari pengolahan rajungan memiliki jumlah sebanyak 60% dari total berat rajungan. Hal ini menunjukkan bahwa potensi dari cangkang rajungan ini sangat besar dan perlu dimanfaatkan dengan baik. Permasalahan saat ini dari cangkang rajungan adalah penyebarannya yang tidak merata dan jumlahnya yang beragam. Proyek desain utama ini bertujuan mendesain model bisnis yang kolaboratif yang dapat menyediakan bahan baku cangkang sesuai dengan kebutuhan industri pengolah cangkang. Hasil validasi prototipe menunjukkan bahwa rancangan solusi yang diberikan diterima dan dapat menjawab permasalahan yang ada. Berdasarkan hasil penelitian juga dapat diambil kesimpulan bahwa UPLCT layak untuk dijalankan dilihat dari aspek finansial dengan kriteria nilai NPV lebih dari 0 (Rp201.257.103), IRR lebih dari Suku Bunga Dasar Kredit (SBDK) ritel BRI (8,25%) yaitu 14,67%, B/C Ratio lebih dari 1 (1,3), dan payback period kurang dari asumsi umur proyek 20 tahun (4,93 tahun)., Blue swimming crab is one of the marine product commodities that has great processing potential from its meat and shells. The utilization of crab shells can be processed into various types of products with different added values. The solid waste generated from crab processing accounts for as much as 60% of the total crab weight. This shows that the potential of this crab shell is very large and needs to be utilized properly. The current problem of crab shells is their uneven distribution and varying amounts. This main design project aims to design a collaborative business model that can provide shell raw materials according to the needs of the shell processing industry. The prototype validation results show that the solution design provided is accepted and can answer existing problems. Based on the research results it can also be concluded that UPLCT is feasible to run from a financial perspective with criteria for an NPV value of more than 0 (Rp201,257,103), IRR is more than BRI's retail prime lending rate (SBDK) (8.25%), namely 14.67%, the B/C ratio is more than 1 (1.3), and the payback period is less than the assumed project life of 20 years (4.93 years).
Keyword: Crab shell, Financial, Feasibility

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