Judul: Kajian beban pencemaran Sungai Cikao Kabuapten Purwakarta
Abstrak: Kondisi Sungai Cikao saat ini diperkirakan telah mengalami penurunan kualitas air disebabkan berbagai aktivitas manusia. Penelitian ini bertujuan untuk mengidentifikasi sumber pencemar air Sungai Cikao, menghitung besar beban pencemaran setiap sumber-sumber pencemar dan dampak beban pencemaran (BP) terhadap kualitas air dan membandingkan besar BP dengan daya tampung beban pencemaran (DTBP). Analisis beban pencemaran dilakukan melalui pendekatan Rapid Assesment, sedangkan status pencemaran dianalisis dengan metode Storet. Hasil identifikasi menunjukkan bahwa sumber pencemar dominan di sekitar Sungai Cikao adalah limbah permukiman, pertanian, peternakan dan industri, dengan total beban pencemaran terhadap nilai BOD sebesar 478.188 ton/bulan, COD sebesar 941.418 ton/bulan, TSS sebesar 240.840 ton/bulan dan TN sebesar 242.274 ton/bulan. Selisih antara DTBP terhadap BP pada nilai BOD sebesar -3 755.593 ton/tahun, COD sebesar 5 225.217 ton/tahun, TSS sebesar 3 718.810 ton/tahun dan TN sebesar 30 069.427 ton/tahun. Hasil analisis status pencemaran dengan metode Storet menunjukkan bahwa kualitas air di Sungai Cikao termasuk kategori tercemar berat
Keyword: Cikao River, pollution resource, waste discharge, water quality

Judul: Kajian Beban Pencemaran dan Daya Tampung Beban Pencemaran Sungai Ciliwung Hulu Segmen Kabupaten Bogor
Abstrak: Water quality (KA) of the upstream of Ciliwung River was important affecting the efforts to comply water necessities for community’s activities. Thus there need a study to determine the change of KA due to waste discharge (BP) that flow into stream. The objectives of this research were to identify river’s utilization, source of pollutant, to evaluate condition of river’s KA, and to calculate BP and BP capacity (DTBP). Literature review method was used to collect secondary data that consisted of KA, demography, tourism, total of livestock, total area of farming land and total of industry. Primary data were collected by using field observation and interview to the community. Used analysis method was Rapid Assessment of Sources of Air, Water and Land Pollution to determine status quality of water and BP; meanwhile DTBP was calculated based on BMA class I (PP No 82 of 2001) and utilization of river and source of pollutant were analyzed descriptively. Main source of BP was from river utilization by community which includes domestic, animal husbandry and farming wastes. Main BP couldn’t be contained anymore due to limited DTBP of river. Total of BP excesses were, respectively, 7.3356 ton month¹ BOD, 1005.82 ton month¹ COD and 478.29 ton month¹ TSS. Generally, quality status of upstream Ciliwung River’s water in 2008-2012 was ranged between moderately polluted to fine; it could be seen from parameters such as BOD, COD, phosphate, DO, TSS and total coli that have been exceding BMA.
Keyword: water quality, source and waste discharge, capacity

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