Judul: Characteristics of Beef Rendang with Addition of (Zingiber officinale var. Rubrum) During Storage at Room Temperature
Abstrak: Rendang adalah makanan khas Minangkabau yang dibuat selama 4-6 jam dan disimpan untuk waktu yang lama. Selama penyimpanan rendang dapat mengalami ketengikan sehingga penambahan jahe merah selama pembuatan rendang diharapkan mampu meningkatkan antioksidan untuk mencegah ketengikan serta meningkatkan umur simpan rendang. Penelitian ini bertujuan untuk menganalisis karakteristik fisikokimia, mikrobiologi, organoleptik dan aktivitas antioksidan rendang daging dengan penambahan jahe merah sebanyak 0%, 15%, dan 30%. Rendang yang diuji disimpan di dalam stoples penyimpanan yang tertutup rapat dan dibiarkan pada suhu ruangan. Hasil penelitian menunjukkan bahwa penambahan jahe merah berpengaruh nyata (p<0,05) terhadap nilai pH, aktivitas air, kadar air, kadar protein, nilai TBARS, total plate count (TPC), aktivitas antioksidan dan kapasitas antioksidan, namun tidak berpengaruh terhadap kadar abu, kadar lemak, dan keempukan. Penambahan jahe merah pada pembuatan rendang daging nyata meningkatkan (p<0,05) nilai pH, kadar air, nilai aw, kadar protein, dan aktivitas antioksidan serta mampu menurunkan peningkatan nilai TBARS dan menghambat pertumbuhan mikrobiologi selama penyimpanan. Karakteristik kadar abu, kadar lemak dan keempukan tidak menunjukkan perbedaan nyata dengan rendang daging tanpa penambahan jahe merah secara statistika. Dari semua sampel yang telah diuji, pemberian jahe merah sebanyak 30% memberikan hasil terbaik. Secara organoleptik, penambahan jahe merah tidak memberi pengaruh terhadap kesukaan panelis terhadap rendang yang dihasilkan. Dapat disimpulkan penambahan jahe merah pada pembuatan rendang daging memberikan efek positif terhadap karakteristik fisikokimia, meningkatkan aktivitas antioksidan, serta menghambat pertumbuhan mikrobiologi.
Keyword: antioxidant, microbiology, organoleptic, red ginger, rendang

Judul: Sifat Fisikokimia, Organoleptik dan Aktivitas Antioksidan Dendeng Sapi dengan Penambahan Jahe Merah (Zingiber officinale Var. Rubrum) Segar
Abstrak: Dendeng merupakan produk olahan daging yang dapat mengalami ketengikan akibat reaksi peroksidasi lipid. Ketengikan dapat dicegah dengan penggunaan antioksidan, seperti jahe merah. Penelitian ini bertujuan menguji sifat fisikokimia, organoleptik dan aktivitas antioksidan dendeng sapi yang diberi penambahan jahe merah segar dengan konsentrasi sebanyak 0%, 10% dan 20% berdasarkan berat daging. Sampel dendeng yang diuji organoleptik berupa dendeng mentah dan matang. Pengujian sifat fisikokimia dan aktivitas antioksidan menggunakan dendeng yang mentah. Hasil penelitian menunjukkan bahwa penambahan jahe merah segar terhadap dendeng sapi berpengaruh nyata (P<0,05) terhadap nilai pH, aw, kadar air dendeng sapi, dan karakteristik organoleptik pada atribut rasa, aroma dan kelenturan dendeng sapi mentah dan matang. Penambahan jahe merah segar tidak berpengaruh nyata pada nilai TBARS dan aktivitas antioksidan. Secara keseluruhan, dendeng sapi dengan penambahan jahe merah segar sebesar 10% menunjukkan hasil terbaik untuk pengujian sifat fisikokimia, organoleptik dan aktivitas antioksidan., Jerky or dendeng is a processed meat product that can have rancidity due to lipid peroxidation reactions. Rancidity can be prevented by using antioxidants such as red ginger. This study aims to examine the physicochemical, sensory properties and antioxidant activity of beef jerky with the addition of fresh red ginger with proportion 0%, 10% and 20% based on beef weight. The sample that used for sensory evaluation were raw and cooked dendeng. Physicochemical properties as well as antioxidant activity measurement used raw dendeng. The addition of fresh red ginger to dendeng had a significant effect (P<0,05) on pH value, water activity dan sensory properties of taste, flavor and flexibility attribute. The addition of fresh red ginger to dendeng had no significant effect on TBARS value and antioxidant activity. Overall, beef jerky with the addition of 10% fresh red ginger showed the best results for physicochemical, sensory properties and antioxidant activity measurement.
Keyword: antioxidant, beef jerky, fresh red ginger, organoleptics

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