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: Serangan Rayap Tanah terhadap Tegakan Pohon di Kebun Raya Bogor
Abstrak: Pelestarian dan perlindungan terhadap pohon-pohon yang tersimpan di Kebun Raya Bogor (KRB) perlu dilakukan untuk menghindari kerusakan oleh berbagai macam penyakit maupun serangga perusak termasuk rayap. Penelitian bertujuan menganalisis frekuensi serangan rayap dan mengidentifikasi jenis rayapnya, menganalisis preferensi rayap terhadap jenis pohon, serta tingkat kerusakan pohon akibat serangan rayap di KRB. Penelitian dilakukan dengan menggunakan metode jalur sampling dengan Intensitas Sampling 20%. Hasil penelitian menunjukkan bahwa sebanyak 213 (100%) pohon contoh di KRB terserang rayap. Spesies rayap tanah yang ditemukan sekurang-kurangnya terdapat empat spesies yaitu Coptotermes curvignathus Holmgren, Macrotermes gilvus Hagen, Odontotermes javanicus Holmgren dan Nasutitermes matangensis Haviland. Rayap M. gilvus banyak ditemukan pada pohon Pterocarpus indicus, Dysoxylum spp., Shorea spp., dan Dimocarpus spp.. Rayap O. javanicus banyak ditemukan pada pohon Vitex cofassus, Dehaasia incrassata, Heritiera spp., dan Cordia spp.. Rayap N. matangensis banyak ditemukan pada pohon Canarium indicum, Dysoyylum spp., dan Sindora spp.. Rayap C. curvignathus banyak ditemukan pada pohon Araucaria columnaris, Agathis sp., dan Pinus spp. Tingkat kerusakan pohon contoh akibat serangan rayap sebesar 10-90%., Preservation and protection of trees stored in the Bogor Botanical Gardens (KRB) need to be done to prevent damage by various kinds of diseases and destructive insects including termites. This study aimed to analyze the frequency of termite attacks and to identify the type of termites, to analyze termite preferences for tree species, as well as the degree of tree damage due to termite attacks in KRB. The research was conducted using the path sampling method with a sampling intensity 20%. The results showed that as many as 213 (100%) sample trees in KRB were attacked by termites. There are at least four subterranean termite species found, namely Coptotermes curvignathus Holmgren, Macrotermes gilvus Hagen, Odontotermes javanicus Holmgren, and Nasutitermes matangensis Haviland. Termites M. gilvus are found in Pterocarpus indicus, Dysoxylum spp., Shorea spp., and Dimocarpus spp. Termites O. javanicus are found in Vitex colossus, Dehaasia incrassata, Heritiera spp., and Cordia spp. Termites N. matangensis is found in Canarium indicum, Dysoxylum spp., and Sindora spp. Termites C. curvignathus can be found in Araucaria columnaris, Agathis sp., and Pinus spp. The level of damage to sample trees due to termite attacks is 10-90%.
Keyword: Attack frequency, subterranean termites, termite preferences, tree health

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