Judul: Pemangkasan Tanaman Teh (Camellia sinensis (L.) O. Kuntze) di Perkebunan Ciater Subang-Jawa Barat
Abstrak: Kondisi lingkungan terutama suhu dan kelembaban udara sangat berpengaruh terhadap hasil pemangkasan. Meskipun demikian pemangkasan dapat dilakukan sepanjang tahun dengan memilih tipe pangkasan yang tepat. Kegiatan magang ini bertujuan untuk mengamati, mempelajari dan menganalisa pangkasan bersih dan pangkasan jambul pada tanaman teh di Perkebunan Ciater.
Keyword: 

Judul: Pengelolaan pemangkasan teh (Camellia sinensis (L.) O. Kuntze) di PTP Nusantara VIII, Kebun Ciater, Subang, Jawa Barat
Abstrak: Pemangkasan merupakan salah satu kegiatan pemeliharaan tanaman teh periode tanaman menghasilkan (TM). Tindakan pemangkasan dapat mengganggu pertumbuhan dan produktivitas tanaman. Oleh karena itu, pemangkasan harus dilaksanakan secara hati-hati dan memperhatikan kondisi tanaman lingkungan hidupnya. serta Kegiatan magang secara umum bertujuan untuk meningkatkan keterkaitan dan kesepadanan antara proses pendidikan dengan lapangan kerja, meningkatkan kemampuan profesional mahasiswa dan memperoleh umpan balik dari dunia kerja bagi perguruan tinggi. Adapun tujuan khususnya untuk meningkatkan pengetahuan dan memberikan pengalaman kerja kepada mahasiswa. Magang dilaksanakan selama empat bulan, mulai Pebruari hingga Juni 2000 di Perkebunan Ciater PTPN VIII Subang, Jawa Barat. Metode yang digunakan adalah dengan bekerja di lapang, dan mengumpulkan data secara langsung dan tidak langsung. Selanjutnya dilakukan analisa data secara sederhana. Tanaman teh di Perkebunan Ciater secara umum termasuk tanaman teh menghasilkan (TM). Kegiatan pemeliharaan yang dilaksanakan di Perkebunan Ciater meliputi pengendalian hama dan penyakit, pengendalian gulma, pemupukan dan pemangkasan. Jenis pangkasan yang dilakukan di Perkebunan Ciater adalah pangkasan bersih dan pangkasan jambul. Pangkasan jambul dilaksanakan di Afdeling Ciater IV dan hanya pada kondisi yang sangat diperlukan, yaitu pada saat musim kemarau dengan mempertimbangkan ketersediaan tenaga pemangkas. Perkebunan Ciater terletak pada ketinggian 600 -1 600 m dpl dan secara umum menggunakan gilir pangkas 3.5 tahun. Namun sejak tahun 1998, pemangkasan di Perkebunan Ciater mulai mengalami keterlambatan. Hal ini disebabkan oleh keterbatasan jumlah tenaga pemangkas...dst
Keyword: perkebunan teh, Ciater, pemetikan, pemangkasan, pengolahan

Judul: The Construction of Greedy SVP LLL Algorithm
Abstrak: A lattice is a set of all integer linear combination of a set of linearly independent vectors in ℝ𝑛���. The independent vectors are called bases of lattice. Any lattice can be generated from many bases, and these bases have the same cardinality. In the lattice, the most fundamental and renowned problem is the Shortest Vector Problem (SVP). SVP is a tracking problem of the shortest nonzero vector in a lattice with equivalent bases. In two dimensions, SVP problem has resolved exactly by Gauss’ algorithm. When the lattice dimension is higher than two, A.K. Lenstra, H.W. Lenstra and L. Lovasz gave a LLL algorithm to compute approximation of nonzero shortest vector in the lattice. Reduced bases solution obtained from LLL algorithm still be an approximation and has polynomial running time of arbitrary dimension which large enough. In 1994, Schnoor and Euchner modified this LLL algorithm as a new variant which later was named deep insertion LLL algorithm. This algorithm is a modified version of the LLL algorithm to the terms of the exchange step to improve the accuracy of output of LLL reduced bases and applying it to the subset sum problem. The purpose of this research are: (1) Reconstruct the LLL algorithm and deep insertion LLL algorithm using a geometric approach. (2) Construct a greedy SVP LLL algorithm. (3) Implement the three algorithms in a symbolic programming language, and evaluate them experimentally. A bases ℬ=[𝐛���1,𝐛���2,…,𝐛���𝑛���] in ℝ𝑚��� is called reduced LLL with parameter 𝛿��� if satisfies: (a) |𝜇���𝑗���𝑖���|≤12, for every integer 𝑖���,𝑗��� with 1≤𝑖���<𝑗���<𝑛���. (b)𝛿���‖𝜋���𝑗���(𝐛���𝑗���)‖2≤‖𝜋���𝑗���(𝐛���𝑗���+1)‖2, for 𝑗���=1,2,…,𝑛���−1,where 𝛿��� is a reduced parameter of real numbers with 14<𝛿���<1. The first requirement is the reduced basis 𝛿��� must “nearly orthogonal” and in its computation case, this requirement can be reached out by using the Gram-Schmidt’s orthogonalization. While the second requirement is called exchange step, or used to called as Lovasz condition. By using both of these requirements, then they establish the LLL algorithm. Then, Schnoor and Euchner modify the LLL algorithm based on the requirements of the exchange step called the deep insertion LLL algorithm, where the exchange step is based on the comparison of the projected vector in orthogonal complement [𝐛���1,𝐛���2,…,𝐛���𝑘���−1]⊥ after j-th reduction. To construct greedy SVP LLL algorithm, the requirements of the exchange step is based on purely by comparing norm of lattice 𝐛���𝑗��� with norm lattice 𝐛���𝑖��� for 𝑖���=1,2,3…,𝑗���−1. The process of insertion reduced vector after the exchange step also has done greedily. Then, we calculate the number of arithmetic operation in greedy SVP LLL algorithm for further analysis. The result of our exprimentation for three algorithms on the certain matrix size shows that the running time of the three algorithms increases propotional to the size of the matrix. The result also shows that by using 𝛿���=34 for the LLL algorithm and the deep insertion LLL algorithm, and the greedy SVP LLL algorithm which is a new variant made by using no parameter of 𝛿���, outperform of the other of two previous algorithm in terms of speed with the same output.
Keyword: LLL algorithm, LLL deep insertion algorithm, greedy SVP LLL algorithm