Judul: Studi pemanfaatan gambir (Uncaria gambir Roxb) dalam proses pewarnaan kain mori
Abstrak: Gambier is an extract of leaves and branches of gambier plant (Uncaria gambier Roxb). Gambier is one of Indonesia export commodities mostly produced in Sumatera island. Indonesia plays role as the world’s largest gambier exporter. In Indonesia, gambier utilized traditionally as leather tanning material, ingredient of traditional medicine, rust omission, etc. Chemical components of gambier mostly utilized are catechin and tannin. Technology of gambier processing that existed in Indonesia is still low in capacity, so the processing of gambier is mostly done traditionally. This kind of processing resulted on low quality and lack of economical value products of gambier. Therefore, development of processing method and wide utilization of Gambier in industry are needed to increase gambier added value. Tannin and catechin on gambier also can be utilized as colouring agent in textile industry to gain reddish brown colour on batik clothes that will be endure on intense sunlight exposure. Textile industries in Indonesia, especially batik industries, are now developing rapidly where the trend of batik clothes on every occasion is becoming common interest. On technological side, in general the batik industrialists have not done any development on their production sytem and method, so they could be more productive and produce uniformity of product quality. Utilization of natural colouring agent is also not becoming a consideration of most batik industrialists in the environmental issue that is now being widely concerned.
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Judul: Kajian Tekno Ekonomi Pendirian Industri Katekin dan Tanin dari Gambir (Uncaria gambir Roxb).
Abstrak: Gambier is a dried extract from the leaves and twigs of Uncaria gambier (Hunter) Roxb plants. Gambier is one of Indonesian export products which generates foreign exchange for the country. The most demanded component are catechins and tannins. In general, catechin are used in pharmaceutical, cosmetic, and beverage industry. Tannins are widely used as leather tanning, industrial adhesives, industrial paint and dye. The potential demand of catechins and tannins are calculated based on the demand of potential users of multiple products. Based on the calculation, the catechin and tannin potential market involve around 1.090 tons per year for catechin and 207 tons per year for tannin. That amounts are estimated values of some product users, so the potential market value of catechin and tannins is greater. The purpose of this study is to assess the feasibility of the establishment of catechin and tannin industry. The scope of research includes studies of market and marketing, technical and technological, management, environment and legality, and financial aspects. The catechin and tannin industry is planned to be located in Bogor Ciawi considering the conditions that supports of infrastructure, human resource availability, ease of access to markets and production support facilities. Factory production capacity is 10,9 tons of catechin per year and 24,51 tons of tannin. Raw materials that used are gambier from the Lima Puluh Kota regency which has a stable supply of raw materials. This industry needs 40 workers with their respective job descriptions. It produces wastes in solid, liquid, and gas, but the numbers are relatively small and still below the threshold standard for the environment. The amount of investment needed is Rp Rp12.079.053.600,- consist of fixed investment cost Rp 8.374.740.000,- and working capital cost Rp 3.704.313.600,-. The NPV value is Rp 67.196.856.477, -. The IRR is 86,11 percent. The Net value of B / C is 6,56.The Payback period is 1,62 years. The financial analysis showed that the industry is feasible to set up.
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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