Judul: Kelimpahan Mikroplastik pada Sedimen di Muara Sungai Citarum, Bekasi, Jawa Barat
Abstrak: Lingkungan perairan yang baik sangat penting bagi kehidupan biota perairan. Kerusakan lingkungan perairan akan memiliki dampak terhadap lingkungan perairan dan biota. Sampah plastik yang terdiri dari makroplastik dan mikroplastik merupakan salah satu sumber kerusakan lingkungan perairan. Mikroplastik di sedimen dapat berdampak negatif bagi biota perairan dan rantai makanan. Tujuan penelitian ini untuk mendeskripsikan sebaran dan kelimpahan mikroplastik pada sedimen. Pengambilan contoh dilakukan di Desa Pantai Bahagia, Muara Gembong, Sungai Citarum, Kabupaten Bekasi, Jawa Barat pada bulan Oktober dan Desember 2018. Pada penelitian ini dilakukan dua analisis, yaitu analisis kelimpahan mikroplastik dan FT-IR. Uji statistik yang digunakan yaitu Kruskal Wallis dan Mann Whitney. Hasil yang ditemukan paling dominan mikroplastik dengan tipe fiber dan hal ini menunjukkan mikroplastik lebih banyak berasal dari monofilamen jaring ikan, tali, dan kain sintesis. Kelimpahan mikroplastik paling tinggi ditemukan di stasiun yang paling dekat dengan laut, sebaran mikroplastik semakin mendekati laut kelimpahannya semakin tinggi.
Keyword: biota perairan, mikroplastik, sedimen

Judul: Komposisi dan Kelimpahan Makroplastik dan Mikroplastik pada Air di Muara Sungai Citarum, Kabupaten Bekasi, Jawa Barat
Abstrak: Rusaknya ekosistem perairan disebabkan pencemaran yang akibat oleh tingginya sampah plastik. Rata-rata tingkat produksi plastik sebesar 1,65 juta ton setiap tahunnya. Tingginya produksi dan konsumsi plastik dapat menjadi ancaman bagi lingkungan. Penelitian ini bertujuan menganalisis komposisi dan kelimpahan makroplastik dan mikroplastik pada air di muara Sungai Citarum. Pengambilan data dilaksanakan pada bulan Oktober hingga Desember 2018 dengan lokasi pengambilan data di muara Sungai Citarum, Kabupaten Bekasi, Provinsi Jawa Barat. Contoh diambil menggunakan Plankton net pada tiga kedalaman. Analisis makroplastik dan mikroplastik dilakukan secara mikroskopis dengan bantuan SRC dan mikrometer. Analisis data menggunakan uji statistik yaitu Uji Kruskal Wallis. Kelimpahan makroplastik dan mikroplastik pada sampel air di Sungai Citarum, yaitu 874-1332 partikel/m3. Kelimpahan makroplastik dan mikroplastik paling tinggi ditemukan pada bulan Oktober. Tipe makroplastik dan mikroplastik yang paling dominan ditemukan adalah fiber yang ditemukan di permukaan perairan. Warna makroplastik dan mikroplastik yang paling dominan ditemukan adalah warna hitam dan transparan. Ukuran makroplastik dan mikroplastik yang dominan ditemukan yaitu ukuran 100-1000 μm.
Keyword: plastik, tipe, ukuran dan warna

Judul: Algorithm Construction of HLI Hash Function
Abstrak: Cryptography is a study of mathematical techniques related to aspects of information security regarding on confidentiality, data integrity, entity authentication, and data origin authentication. Data integrity is a service, which is associated with the conversion of data carried out by unauthorized parties. To maintain data integrity, one can use hash functions. An hash function is a computationally efficient function to map an arbitrary length bitstring to a fixed length bitstring called as hash value. The use of hash function in maintaining the information integrity and authentication is in digital signatures, virus protection, and software distribution. Illustration of the hash function in the integrity and authentication of information that is emailed as follow. The sender sends the information and hash value to the recipient. If the hash value of the information is equal to the hash value that is sent by the sender, then information has not been changed. Otherwise the information has been changed. An hash function has two properties, one way and collision resistance. An hash function is called one way if it is computationally infeasible to find any input such that when given any hash value . Meanwhile an hash function is called collision resistant if it is computationally infeasible to find any two inputs where such that . The purpose of this study is to construct a HLI hash function algorithm, to analyze the speed and security of the hash functions as a results of construction. Furthermore, it is to compare it with SWIFFT. Hash function is constructed based on the result of algebraic operations on modular polynomial ringwith . Modular polynomial ring noted as is a set of all polynomials of degree at most with coefficients in . can be represented as a set of integer vector of modulo in dimension . So, it is simple to implement in a computer. In vector operations, is lattice . Furthermore, alattice that is defined from certain polynomial ring is called ideal lattice. HLI hash function is consists of addition and multiplication algorithm in the ring. Addition algorithm consists of sumation operations of modulo and multiplication consists of multiplication operations of modulo . Generally, algorithm of HLI hash function consists of multiplication operations of modulo and addition operations of modulo . However, if the input is binary number then multiplication algorithm only consists of multiplication operation of modulo , so algorithm of HLI hash function consists of multiplication operations of modulo and addtion operations of modulo . An hash function is secured if it has two properties, i.e., one way and collision resistance. HLI hash function hash is one way, it is following the proof of Micciancio. It is has collision resistant because of polynomial is irreducible over and monic. Moreover, it is proved that for every unit vector , the vector is small vector. If the input of hash function is a binary number then HLI hash function only involves addition operations of modulo . So the time that used almost same with SWIFFT. The excellence of HLI hash function is the key size smaller than SWIFFT. This effect on
Keyword: hash function, modular polynomial ring, lattice