Judul: Analisis kelayakan finansial budidaya jamur merang (Volvariella volvaceae) (studi kasus usaha agribisnis putra hasan mushroom di kecamatan Karang Bahagia, Bekasi, Jawa Barat)
Abstrak: Di Indonesia jamur merang maupun jamur lain merupakan komoditas pertanian yang memiliki prospek sangat baik untuk dikembangkan, baik untuk ekspor maupun untuk mencukupi permintaan pasar dalam negeri yang terus meningkat. Masyarakat sudah mulai mengerti akan nilai gizi jamur. Untuk budidaya jamur hanya dibutuhkan ketelitian dan modal yang tidak terlalu besar, tetapi nilai ekonominya cukup tinggi sehingga masyarakat tertarik untuk melakukan budidaya jamur merang. Salah satu masyarakat yang tertarik dan kemudian merealisasikan untuk melakukan budidaya jamur merang adalah Putra Hasan Mushroom.
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Judul: Financial Feasibility Study of Straw Mushroom Farming in Bojongmangu Village Subdistrict Bojongmangu of Bekasi
Abstrak: Jamur merang adalah salah satu jamur konsumsi yang memiliki permintaan tinggi, sehingga banyak dikembangkan salah satunya di Desa Bojongmagu. Produksi jamur merang di Desa Bojongmangu memiliki kelemahan, yaitu produksi yang tidak menentu sehingga relatif rentan terhadap faktor lingkungan. Hal ini akan memengaruhi keputusan petani untuk berusahatani, karena tidak diketahui secara pasti kelayakan usahatani. Investasi yang diperlukan juga tidak sedikit dan produksi yang tidak menentu akan memengaruhi kelayakan usahatani. Tujuan dari penelitian ini untuk (1) mengidentifikasi aspek-aspek kelayakan usahatani jamur merang, (2) mengestimasi kelayakan finansial usahatani jamur merang, (3) menganalisis pengaruh penurunan produksi jamur merang, penurunan harga jual jamur merang, dan peningkatan harga kapas terhadap kelayakan usahatani jamur merang. Metode analisis yang digunakan yaitu analisis kelayakan finansial, analisis sensitivitas, dan analisis switching value. Usahatani jamur merang layak untuk diusahakan, karena telah sesuai dengan aspek-aspek kelayakan serta kriteria investasi yaitu NPV, Net B/C, Gross B/C, IRR, dan Payback Period. Penurunan produksi dan harga jual jamur merang segar memberikan dampak paling besar terhadap usahatani jamur merang., Straw mushroom is one of edible mushrooms has a high demand, it is widely developed, one of them in Bojongmagu Village. Productions of straw mushroom in Bojongmangu Village has a weakness, that is erratic production it is relatively vulnerable to environmental factors. This will affect the decision of farmers to farm, because it is not known with certainty the feasibility of straw mushroom farming. The investment required is also not small and uncertain production will affect the feasibility of farming. The purpose of this research for (1) identify feasibility aspects of straw mushroom farming, (2) estimate the financial feasibility study of straw mushroom farming, (3) analyzed the effect of decreasing production of straw mushroom, decreasing selling price of straw mushroom, and increasing the price of cotton on the feasibility study straw mushroom farming. The analytical method is financial feasibility analysis, sensitivity analysis, and switching value. Straw mushroom farming is feasible, because complied with the aspects and investment criteria, that is NPV, Net B/C, Gross B/C, IRR, and Payback Period. The decrease in production and selling price of straw mushroom had the biggest impact.
Keyword: cost-benefit analysis, horticulture, investment criteria, sensitivity analysis, switching value

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