Judul: Aktivitas Antibakteri Ekstrak dan Fraksi Etanol 70% Daun Sirih Merah (Piper crocatum) terhadap Bakteri Escherichia coli pBR322
Abstrak: Sirih merah (Piper crocatum) merupakan salah satu tanaman herbal yang dapat berfungsi sebagai antibakteri. Penelitian ini bertujuan mengukur dan menguji aktivitas antibakteri ekstrak etanol 70% dan fraksinasi bertingkat yakni n-heksana, etil asetat, dan air daun sirih merah terhadap bakteri spesifik Escherichia coli pBR322 berdasarkan aktivitas dan konsentrasi hambat minimum. Eksraksi dengan metode maserasi menghasilkan rendemen kasar untuk dilanjutkan fraksinasi berdasarkan tingkat kepolarannya. Aktivitas antibakteri dilihat dengan adanya zona hambat yang muncul pada konsentrasi tertentu. kadar hambat minimum dilihat dengan adanya zona hambat yang muncul pada konsentrasi minimum. Berdasarkan hasil penelitian, aktivitas antibakteri terbaik ditunjukkan oleh fraksi n-heksana dengan nilai 2.40 mm ± 0.14 di konsentrasi 1000 ppm. Konsentrasi minimum berada pada 100 ppm dengan nilai 0.60 mm ± 0.56 yang dimiliki oleh fraksi nheksana.
Keyword: Aktivitas antibakteri, daun sirih merah, Eschericia coli pBR322, konsentrasi hambat minimum

Judul: Aktivitas Antibakteri Minuman Fungsional Berbasis Daun Sirih Merah (Piper crocatum) dengan Enkapsulasi Maltodekstrin terhadap Bakteri Escherichia coli pBR322
Abstrak: Sirih merah (Piper crocatum) merupakan salah satu tanaman herbal yang dapat berfungsi sebagai antibakteri. Penelitian ini bertujuan mengukur dan menguji aktivitas antibakteri pada minuman fungsional berbahan baku sirih merah dengan enkapsulasi maltodekstrin terhadap bakteri spesifik Escherichia coli pBR322 berdasarkan aktivitas dan Konsentrasi Hambat Minimum (KHM). Ekstrasi sirih merah, jahe merah, perasan jeruk nipis dan kayu manis menggunakan air suling . Aktivitas antibakteri dilihat dengan adanya zona hambat yang terjadi pada konsentrasi tertentu. Kadar Hambat Minimum (KHM) dilihat dengan adanya zona hambat yang terjadi pada konsentrasi minimum. Hasil menunjukkan aktivitas antibakteri terbaik adalah minuman fungsional dengan nanoenkapsulasi maltodekstrin 20% dengan nilai 1.95 ± 0.14 pada konsentrasi 10000 ppm. Konsentrasi minimum untuk menghambat bakteri berada pada 200 ppm dengan nilai 0.28 ± 0.26 yang dimiliki oleh minuman fungsional nanoenkapsulasi.
Keyword: Antibakteri, Daun sirih merah, Minuman fungsional, Konsentrasi Hambat Minimum (KHM)

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