Judul: Dehydration of tempeh with traditional spicy using sunbeam food dehydrator type DT5600
Abstrak: Tempeh is one of the most popular traditional food consumed by Indonesian people for many years. The addition of spicy was one of the preservation methods that could expand the shelf life until four weeks. The performance test is needed to determine the effect of temperature through quality parameter of the best slice spicy tempeh. The objectives of this research were to conduct the performance test of Sunbeam Food Dehydrator DT5600 and to determine the effect of temperature through the quality parameter after the addition of spicy to tempeh. The drying temperature of 75 °C had shorter drying time and had the larger drying rate compare with the temperature of 55 °C or 35 °C. The spicy addition treatment also had the effect on drying rate and drying efficiency, where with the addition of spicy would increase its value. Consumption drying energy was around 10.6 – 27.5 MJ/kg moisture content. The protein concentration was more than 40%. Based on the hedonic test and laboratory test, panelist tend to like and no microbial contaminants.
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Judul: The Impact of Blanching and Vacuum Packaging to The Shelf Life of Fresh Seasoned Tempe
Abstrak: Tempe is an indigenous fermented food from Indonesia, prepared by the action of molds, Rhizopus sp., on cooked soybeans. In 2012, up to 60% of soybean production went to tempe industry with consumption of tempe reaching 8.5 kg per person per year in Indonesia. However, the export of tempe seems still impossible due to its perishable characteristic whose shelf life is very short. Preblanching and vacuum packaging were expected to extend the shelf life of tempe. This research was aimed to study the application of blanching and vacuum packaging on the shelf life of fresh-seasoned tempe. Steam blanching of 80 oC for three minutes was selected from pre-investigation for pre-treatment of the tempe without inducing cooked-tempe characteristic. The result of main research revealed that steam blanching and vacuum packaging were able to extend the shelf life of fresh-seasoned tempe for two days in room temperature (23-24 oC), 32 days in refrigeration temperature (4-6 oC), and 49 days in chilling temperature (0-4 oC). The pH of tempe was found increasing during storage with texture getting overstuffed or tender during storage.
Keyword: Bogor Agricultural University, vacuum packaging, storage temperature, shelf life, Fresh-seasoned tempe

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