Judul: Keanekaragaman Spesies Rayap Tanah di Lingkungan Pemukiman Kota Bogor, Jawa Barat
Abstrak: Kebutuhan masyarakat Kota Bogor akan tempat tinggal semakin meningkat, sehingga mengubah kondisi lingkungan yang dapat memengaruhi keberadaan organisme pengganggu, terutama rayap tanah. Penelitian ini bertujuan untuk mengidentifikasi spesies rayap tanah dan keanekaragamannya di Kota Bogor, mengetahui karakteristik tanah dan cuaca, serta mengetahui intensitas kerusakan dan frekuensi serangan rayapnya. Penelitian dilakukan di 12 kelurahan contoh. Disetiap kelurahan contoh, ditanam 25 kayu umpan (2 x 2 x 46 cm) dari kayu pinus yang sebelumya telah diberi perlakuan tekanan uap air (105 ℃, 1 bar, 5 jam). Disetiap kelurahan contoh diambil tanah contoh. Data cuaca diukur di salah satu kelurahan contoh. Hasil penelitian menunjukkan bahwa spesies rayap yang ditemukan ada 3 jenis yaitu Microtermes sp., Macrotermes sp., dan Schedorhinotermes sp. Spesies rayap tanah di lingkungan pemukiman Kota Bogor didominasi oleh Microtermes sp. Karakteristik tanah dan cuaca sangat mendukung kehidupan rayap di Kota Bogor. Nilai frekuensi serangan rayap sebesar 38% (tinggi) dan nilai intensitas kerusakan kayu adalah 6-9.
Keyword: frekuensi serangan, intensitas kerusakan, karakteristik tanah, Pinus merkusii, tekanan uap panas

Judul: Kelas Bahaya Serangan Rayap Tanah di Kota Bogor, Jawa Barat.
Abstrak: Serangan rayap pada gedung dan bangunan di Kota Bogor sebagai salah satu kota besar merupakan ancaman yang serius mengingat angka kerugian yang ditimbulkan. Penelitian ini bertujuan mengetahui jenis dan sebaran rayap tanah, menganalisis hubungan antara karakteristik tanah dengan intensitas kerusakan dan frekuensi serangan rayap tanah, serta menentukan kelas bahaya serangan rayap di Kota Bogor. Penelitian dilakukan di 12 kelurahan di Kota Bogor yang dipilih secara acak. Setiap kelurahan ditanam 25 sampel kayu pinus (Pinus merkusii) selama tiga bulan dengan ukuran 2 cm x 2 cm x 46 cm (ASTM D 1758-06) sebagai kayu umpan yang sebelumnya telah diberi perlakuan tekanan uap air (105 ℃, 1 bar, 5 jam). Hasil penelitian menunjukkan bahwa spesies yang ditemukan di permukiman Kota Bogor terdapat tiga jenis yaitu Microtermes sp., Macrotermes sp., dan Schedorhinotermes sp., Rata-rata frekuensi serangan rayap tanah terhadap kayu umpan sebesar 70% (sangat tinggi) dan nilai intensitas serangan 6. Hasil analisis korelasi sederhana menunjukkan bahwa terdapat hubungan antara pH tanah dan kadar liat tanah dengan intensitas kerusakan masing-masing sebesar 23.7%. Kota Bogor memiliki rata-rata serangan rayap tanah yang tinggi. Luas kelas bahaya rendah ±3.74 km2, luas kelas bahaya sedang ±52.88 km2 dan luas kelas bahaya tinggi ±59.9 km2.
Keyword: frekuensi serangan, intensitas kerusakan, kayu umpan, Pinus merkusii

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