Judul: Pemangkasan Tanaman Teh (Camellia sinensis L. (O) Kuntze) di PT Tambi Unit Perkebunan Tambi, Wonosobo, Jawa Tengah
Abstrak: Apprenticeship aims to analyze the management of the tea plant against specific aspects of the cuts and add insight and real work experience. Internship was conducted from February to May 2012 in Plantation Unit Tambi, PT Tambi, Wonosobo, Central Java. The purpose of pruning is to study the management of a good and proper pruning, so as to improve the quality and quantity tea plants. Plantation Unit Tambi using pruning type of production and the type of clipping middle clean. Less time of trimming activities in accordance with the planned time due less of man power of trimmer. The factors that affect the success and accuracy of trimming the plant conditions, in accordance with the type of clipping crop conditions, while proper pruning, proper pruning tools and skills of the workforce. As a result of the lack of proper pruning branches that damage the tea plant, diameter and height fields are not appropriate quotation and shoot growth rate becomes slow causing production to decline. Branch damage is quite high at Block Park caused by the use of the machine tool mechanical pruning cut. Therefore it is necessary for good supervision and coaching skills that are appropriate in order to get good results and proper clipping.
Keyword: 

Judul: Pengelolaan Pemangkasan Teh (Camellia sinensis (L.) O. Kuntze) di Perkebunan Medini, PT Rumpun Sari Medini, Kabupaten Kendal, Jawa Tengah
Abstrak: The internship was conducted at Medini Estate, PT Rumpun Sari Medini, Kendal, Central Java from February until June 2011. Activities performed during the internship is a field worker for one month, as assistant foreman for one month, as assistant chief of the estate for two month. The purpose of the internship is improve knowledge, gain work experience and studying the management aspects of pruning tea, both technical and managerial aspects. Pruning is maintenance activities to rejuvenate the tea plant for increase the production of shoots. Pruning activity of tea in Medini Estate, PT Rumpun Sari Medini, Central Java was good enough.
Keyword: 

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