Judul: Evaluasi Kualitas Pengolahan Air Kampus IPB Dramaga yang Berasal dari Sungai Cihideung.
Abstrak: Kebutuhan air bagi keberlangsungan kegiatan di kampus IPB Dramaga dipenuhi melalui pengolahan air yang diantaranya bersumber dari Sungai Cihideung. Penelitian ini bertujuan memantau mutu air hasil pengolahan dan air yang diterima oleh konsumen pada 3 bulan pengamatan, yaitu pada bulan Agustus, September, dan Oktober 2015. Hasil pengamatan menunjukkan mutu air hasil penjernihan dan air di tingkat konsumen, yaitu di Departemen Statistika dan Departemen Kimia pada 3 bulan tersebut tidak berbeda serta telah memenuhi baku mutu air kelas I (PP No. 82 Tahun 2001) pada parameter total koliform, bau, suhu, kekeruhan, total dissolved solid, warna, pH, kesadahan, nitrit, klorida, Cd, Cr, dan Pb, namun tidak bagi parameter Al dan Fe.
Keyword: purification, reference standar, water quality

Judul: Evaluasi Instalasi Pengolahan Air Sungai Cihideung di Kampus IPB Dramaga
Abstrak: Kampus IPB memiliki unit Water Treatment Plant (WTP) Cihideung sebagai upaya untuk mengurangi terjadinya pencemaran air dikarenakan sumber air Cihideung sudah tercemar. Oleh karena itu, proses pengolahan air bersih yang dilakukan pada WTP Cihideung harus optimal agar air yang terdistribusi sesuai dengan standar baku mutu. Tujuan dari penelitian ini adalah untuk mengetahui kualitas air hasil pengolahan di WTP Cihideung kampus IPB Dramaga dan untuk mengetahui kesesuaian unit WTP Cihideung dengan kriteria desain. Penelitian ini dilakukan selama bulan Maret-Juni 2021 di WTP Cihideung Kampus IPB Dramaga. Proses pengolahan dengan WTP konvensional terdiri atas unit intake, koagulasi, flokulasi, sedimentasi, filtrasi, dan ground water tank (GWT). Kualitas air yang dihasilkan oleh WTP Cihideung sesuai dengan baku mutu, kecuali parameter kekeruhan. Hasil evaluasi kinerja unit didapat beberapa nilai parameter yang belum sesuai dengan kriteria desain, yaitu waktu detensi pada koagulasi, kecepatan aliran pada flokulasi-clarifier, serta kecepatan pencucian pada unit filtrasi.
Keyword: unit performance, water treatment plant, water quality

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