Judul: Infestasi Gulma pada Agroekologi yang Berbeda di Perkebunan Kelapa Sawit (Elaeis guineensis Jacq.) Tambusai Estate, Kab. Rokan Hulu, Riau
Abstrak: Weed control in oil palm plantation can improve the productivity of oil palm trees. This in was carried out internship Tambusai Estate, Rokan Hulu, Riau, from February to May 2012. The objective of this apprentice was to improve the knowledge, skills, work experience and analyze factors that affect weed dynamic in different agroecological areal at oil palm plantation. Data were collected by direct method for primary data and indirect method for secondary data. Data of weed were collected using vegetation analysis of 1 m x 1m kuadran. The number of samples were 264. Weed were scored and tested using cluster analysis and shown as a dendogram. The results showed that agro-ecological factors, especially soil subgroup determined weed population and dominance in Tambusai Estate. Weed invasion on palm oil plantation spread based on the nature of the morphology, botany, and nature of damage to plants as well as palm oil is the difference in the form agroekologi subgroup of land. The humid soil conditions is an optimum for weeds Asystasia intrusa (Forssk.) Blume., Nephrolepsis bisserata (Sw.) Schott, and various kinds of other ferns which is the dominant weeds in Tambusai Estate.
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Judul: Pengelolaan Gulma Kelapa Sawit (Elaeis guineensis Jacq.) di Angsana Estate PT Ladangrumpun Suburabadi Minamas Plantation Kalimantan Selatan
Abstrak: The objective of this apprentice was to improve student’s competance on technical and managerial skill. The apprentice was conducted at Angsana Estate PT Ladangrumpun Suburabadi Minamas Plantation,South Kalimantan from February to June 2011. The method used was direct and indirect. Directly method was performed the steps as field worker, foreman and division assistant. Indirect method to collect and plantation reports. There were two methods on weed control according to weed problem at site, first inter-row and second circle weeding. The vegetation analysis result showed that broadleaves weed species dominance at field. Coefficient weed comunity less than 75% so variable of weed community were not homogen. Weed control in Angsana Estate consisted of manual and chemical control. Manual control performed on young (immature) and productive if rainy weather. Chemical control using systemic herbicides. The use of herbicides was done in accordance with principles and criteria for sustainable palm oil. Chemical weed control in Angsana Estate (ASE) was organized called the Block Spraying System (BSS). Not all weeds were eradicated, some weed species have been maintain for a specific purpose (beneficial plant) as maintain soil moisture, increase organic matter and nutrients in the soil and can be a host for predators of pest and diseases. Example of beneficial plants are Euphorbia heterophylla, Cassia cobanensis, Antigonon leptopus dan Turnera subulata.
Keyword: weed in palm oil, beneficial plant

Judul: Photosensor producing based on ferroelectric material of Ba0,5Sr0,5TiO3 doped by Ferrium Oxide (Fe2O3) on a P-Type Silicon Substate Si (100) applied as a digital camera with a single pixel image sensor
Abstrak: Thin film Ba0,5Sr0,5TiO3 (BST) doped with Fe2O3 was grown on p-type silicon substrate (100) using chemical solution deposition (CSD). It used the solvent 2-methoxyethanol with annealing temperature of 850°C and the doping treatment Fe2O3 of 2.5, 5, 7.5, 10 % of the mass formed BST. Pure BST had the highest absorption of 600 nm of light wavelength. Additions Fe2O3 moves highest absorption in the range of 560 nm. Fe2O3 addition was strengthening thin film sensitivity to the effects of light. In general, doping Fe2O3 10% was result the best absorbance and current-voltage of BST thin film. Electrical properties of thin films BST include dielectric, photoconductivity, and dissipation energy. Based on the current-voltage (I-V) analysis, pure BST and doped BST showed photodiode properties. Dielectric values obtained in the range from 23.32 to 243. Based on electrical conductivity data and energy dissipation, BST thin films have shown photodiode characteristics and are therefore suitable as light sensors. The image sensor in a digital camera is also a light sensor. This BST thin film has been scientifically proven to be a light sensor and also it can be applied as an image sensor. This is a novelty image sensor based on thin film Ba0.5Sr0.5TiO3.
Keyword: barium strontium titanate, thin film, photodiode, image sensor, digital camera