Judul: Jamu Kunyit Asam selama Penyimpanan pada Suhu Ruang, Kulkas, dan Pembeku: Perubahan Organoleptik, Fisik, dan Kimia
Abstrak: Jamu merupakan minuman tradisonal Indonesia yang bermanfaat untuk menjaga kesehatan serta kecantikan. Salah satu jamu yang terkenal di masyarakat adalah jamu kunyit asam. Penelitian ini bertujuan menentukan perubahan fisik dan uji organoleptik yang terjadi pada jamu tersebut di dalam botol plastik transparan takberwarna, botol plastik berwarna gelap, botol kaca transparan takberwarna, dan botol kaca berwarna gelap. yang disimpan pada suhu ruang, kulkas, dan pembeku. Penelitian ini menggunakan rancangan faktorial antara jenis dan warna botol yang diragamkan pada berbagai suhu penyimpanan. Hasil penelitian menunjukkan bahwa cara penyimpanan menyebabkan perubahan fisik-kimia antara lain pH, total padatan terlarut, dan nilai Brix; dan organoleptik, yaitu rasa, aroma, dan gas. Penyimpanan terbaik ialah menggunakan kemasan kaca gelap pada suhu pembeku; jamu dapat disimpan hingga 48 hari, sedangkan cara terburuk ialah pada suhu ruang kemasan plastik transparan yang hanya mencapai 5 hari. Penyimpanan menyebabkan perubahan komposisi senyawa volatil pada jamu sehingga mempengaruhi sifat fisik-kimia dan organoleptik pada minuman tersebut.
Keyword: jamu kunyit asam, organoleptik, penyimpanan, sifat fisik-kimia

Judul: Changes in Quality of Emprit Ginger-Based Herbal Drinks (Zingiber officinale var. amarum) During Storage at Various Temperatures and Types of Containers
Abstrak: Jamu merupakan minuman tradisional yang telah dipercaya sejak lama oleh masyarakat Indonesia sebagai minuman kesehatan. Salah satu jamu yang dikenal di masyarakat adalah jamu jahe. Penelitian ini bertujuan menentukan perubahan fisik dan menguji organoleptik jamu tersebut di dalam botol plastik transparan tak berwarna, botol plastik berwarna gelap, botol kaca transparan tak berwarna, dan botol kaca berwarna gelap. yang disimpan pada suhu ruang, kulkas, dan pembeku. Penelitian ini menggunakan rancangan faktorial antara jenis dan warna botol yang diragamkan pada berbagai suhu penyimpanan. Selama penyimpanan, setiap sampel jamu ditentukan perubahan fisiknya yang meliputi pH, nilai brix, dan TPT serta organoleptik yang meliputi rasa, aroma, dan gas tiap hari sekali pada suhu ruang, tiap dua hari sekali pada kulkas, dan tiap tiga hari sekali pada suhu pembeku. Hasil penelitian menunjukkan bahwa cara penyimpanan menyebabkan perubahan fisik-kimia jamu. Berdasarkan penelitian, penyimpanan terbaik jamu jahe ialah menggunakan wadah kaca gelap pada suhu beku yang dapat disimpan hingga 42 hari., Jamu is a traditional drink trusted by Indonesian citizens as a health drink. One of the most popular herbs in the community is jamu ginger. This study aims to determine the physical changes and test the organoleptic properties of the jamu in colorless transparent plastic bottles, dark plastic bottles, colorless transparent glass bottles, and dark glass bottles stored at room temperature, refrigerator temperature, and freezer temperature. The experiment used a factorial design between bottle type and color across various storage temperatures. During storage, each herbal medicine sample was tested for physical changes, including pH, brix value, total soluble solids, and organoleptic changes such as taste, aroma, and gas. The results showed that the storage method affected physicochemical changes in the herbs. The optimal storage method for jamu jahe was using dark glass containers and freezing temperatures, allowing a shelf life of up to 42 days
Keyword: jamu jahe, organoleptic, physico-chemical properties, storage

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