Judul: :Pengendalian Gulma pada Perkebunan Kelapa Sawit (Elaeis guineensis Jacq.) di Kebun Bangun Koling PT Windu Nabatindo Abadi
Abstrak: This intership was conducted at Bangun Koling Estate (BKLE) of PT Windu Nabatindo Abadi (WNA) from March to June 2014. The aim of this activity were to improve knowledge, skill, and experience about oil palm plantation in general and specifically about weed control of oil palm plantation. Collection of data and information was carried out by direct and indirect methods. The author observed weed domination in harvester path of BKLE with observation parameter consisting of species, frecuency, density, and biomass wet weight. Another observation was the damage symptom of voluntary oil palm seedlings (VOPs) spraying in the circle 4 weeks after application. The output of weed domination observation was analyzed with Summed Dominance Ratio (SDR), while VOPs spraying was analyzed descriptively. The harvester path of BKLE was dominated by Nephrolepis biserrata, Ageratum conyzoides, Cyperus rotundus, and Digitaria adscendens. VOPs spraying caused many VOPs dead but few keep growing.
Keyword: Bogor Agricultural University (IPB), weed domination, VOPs damage, summed dominance ratio, harvester path, circle

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: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology