Judul: Study on antimicrobial fractions of atung fruits (Parinarium glaberimum Hassk) as a food preservative
Abstrak: Penelitian ini bertujuan untuk mengkaji lebih mendasar efektivitas kerja antimikroba komponen bioaktif daru buah atung terhadap berbagai mikroba pembusuk dan patogen, serta prinsip-prinsip mendasar pola kinerja antimikrobanya. Sembilan jenis bakteri yang mewakili bakteri Gram positif dan bakteri Gram negatif, pembentukan spora dan non pembentukan spora, patogen dan pembentukan serta batang enteritidia, Salmonella typhimurium, Bacillua aubtilis. Micrococcus luteus, Enterococcus faecalis, Escherichia coli B dan C serta Pseudomonas aeruginosa) diuji dalam penelitian ini.
Keyword: 

Judul: Mempelajari Stabilitas Aktivitas Antimikroba Ekstrak Biji  Atung (Parinarium glaberimum Hassk) dengan Pelarut Etil  Asetat Teknis selama Penyimpanan Terhadap Staphylococcus  aureus
Abstrak: Tujuan penelitian ini adalah untuk mengevaluasi stabilitas antimikroba ekstrak biji atung selama penyimpanan dan menyedakan data dasar bagi pengembangan bentuk dan cara penyimpanan bahan pengawet pangan dari ekstrak biji atung. Peneiitian dibagi menjacii empat tanap, yaitu: 1). Pembuatan ekstrak biji atung menggunakan pelarut teknis; 2). pembuatan ekstrak bubk dan ekstrak cair dari ekstrak biji atung; 3). Pembuatan kurva standar aktivitas antimikroba ekstrak biji atung tefhadap Staphylococcus aureus; dan 4). Pengujian stabilitas antimikroba ekstrak cair dan ekstrak bubuk selama penyimpanan. Pengujian kemurnian pelarut teknis dilakukan dengan melihat suhu didih dan komponen non volatil (pada 105'~). Pengujian aktivitas antimikroba dilakukan dengan metode uji difusi agar dan metode kontak. Selain itu juga dilakukan uji kualitatif terhadap komponen fenolik dan terpenoid ekstrak.
Keyword: 

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