Judul: Heavy Metal Content of Pb, Hg, and Cd in Water and Organs of Blackfin Grouper (Ephinepelus fasciatus Forsskål, 1775) in Bacan Island Waters, North Maluku
Abstrak: Perairan Pulau Bacan menjadi output akhir dari segala kegiatan yang ada di Pulau Bacan, seperti kegiatan pertambangan, kawasan pengembangan industri perikanan, maritim, perumahan dan pariwisata, yang dapat menyebabkan terkontaminasinya perairan dengan logam berat. Penelitian ini bertujuan untuk menganalisis kandungan logam berat (Pb, Hg, dan Cd) pada air dan akumulasi logam berat pada insang, daging, dan usus ikan kerapu di Perairan Pulau Bacan, Maluku Utara. Pengambilan sampel ikan kerapu dan air dilakukan pada 18 Februari 2022. Kandungan logam berat pada organ ikan kerapu dan air dianalisis menggunakan metode Atomic Absorption Spectrophotometer (AAS). Akumulasi logam berat diestimasi melalui bioaccumulation factor, maximum weekly intake, dan meta analysis. Hasil analisis kualitas air menunjukkan konsentrasi logam berat di perairan Pulau Bacan masih dalam baku mutu berdasarkan Peraturan Pemerintah Republik Indonesia No. 22 Tahun 2021. Hasil penelitian menunjukkan tingkat akumulasi logam berat pada ikan kerapu berada pada kategori rendah-sedang, dengan akumulasi tertinggi pada organ usus. Kandungan logam berat Pb dan Cd telah melebihi nilai ambang batas, sedangkan Hg ada di bawah ambang batas yang telah ditetapkan. Batas aman konsumsi ikan kerapu orang dewasa adalah 2,336 kg/minggu dan anak-anak sebesar 0,7 kg/minggu. Penelitian ini diharapkan dapat memberikan informasi mengenai kandungan logam berat pada air dan ikan kerapu di Perairan Pulau Bacan untuk pengelolaan sumberdaya ikan kerapu yang berkelanjutan di Pulau Bacan.
Keyword: heavy metals, Bacan Island water, Ephinepelus fasciatus, Accumulation

Judul: Heavy Metals Content (Pb, Hg, Cd) in Crescent Grunter (Terapon jarbua, Forsskål 1775) in Bacan Island Waters
Abstrak: Pulau Bacan memiliki potensi perikanan dan pariwisata yang tinggi. Kegiatan pariwisata dan kehidupan masyarakat sekitar berpotensi menjadi penyumbang cemaran logam berat ke lingkungan perairan tersebut. Salah satu potensi perikanan dengan nilai ekonomis penting yang terdapat di pulau ini adalah ikan kerong-kerong yang banyak dimanfaatkan sebagai bahan pangan baik dalam kondisi segar maupun olahan ikan asin-kering. Penelitian ini bertujuan menganalisis tingkat bioakumulasi logam berat Pb, Hg, dan Cd pada organ hati, insang, dan daging ikan kerong-kerong (Terapon jarbua, Forsskål 1775) di Perairan Pulau Bacan, Maluku Utara. Pengambilan sampel air, pengukuran kualitas air, serta pengambilan organ hati, insang, dan daging pada ikan kerong-kerong dilakukan pada bulan Februari 2022. Berdasarkan hasil anlisis, nilai kandungan logam berat Pb, Hg, dan Cd pada air telah melampaui baku mutu PP RI No. 22 tahun 2021 dan kandungan logam berat Pb pada hati ikan kerong-kerong ditemukan dalam konsentrasi tertinggi. Biokonsentrasi logam berat tergolong akumulasi rendah, kecuali Pb pada organ hati termasuk akumulasi sedang., Bacan Island has high fishery and tourism potential. Tourism activities and the life of the surrounding community have the potential to contribute to heavy metal contamination in the aquatic environment. One of the fishery potentials with important economic value found on this island is kerong-kerong fish which is widely used as a food ingredient both in fresh condition and processed salt-dried fish. This study aims to analyze the level of bioaccumulation of heavy metals Pb, Hg, and Cd in the liver, gills, and meat of crescent grunter (Terapon jarbua, Forsskål 1775) in Bacan Island waters, North Maluku. Sampling of water, measurement of water quality, as well as harvesting of liver, gills, and meat from crescent grunter was carried out in February 2022. Based on the results of the analysis, the values for the heavy metal content of Pb, Hg and Cd in water exceeded PP RI quality standards No. 22 of 2021 and the content of the heavy metal Pb in the liver of clam fish was found to be in the highest concentration. Bioconcentration of heavy metals is classified as low accumulation, except for Pb in the liver which is classified as moderate accumulation.
Keyword: Bacan Island, crescent grunter, heavy metals

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