Judul: Distribusi dan Struktur Komunitas Makrozoobentos di Pantai Kupang, Desa Lubuk Damar, Kecamatan Seruway, Kabupaten Aceh Tamiang.
Abstrak: Karakteristik substrat suatu perairan memiliki kaitan yang erat dengan jumlah jenis individu dari makrozoobentos yang ditemukan. Penelitian ini bertujuan menentukan distribusi dan struktur komunitas makrozoobentos di Pantai Kupang, Desa Lubuk Damar. Penelitian ini dilaksanakan pada bulan Agustus 2017 dan Januari 2018 di lima titik stasiun dan diidentifikasi dari bulan Agustus sampai Desember 2018. Pengumpulan data makrozoobentos dan sedimen dilakukan dengan metode line transect menggunakan corer. Makrozoobentos yang ditemukan terdiri dari 53 jenis dengan kepadatan total 103.981 individu/m2 yang dikelompokkan ke dalam 10 kelas. Makrozoobentos dari Kelas Polychaeta, Phascolosomatidea, dan Sipunculidea merupakan kelompok makrozoobentos yang ditemukan di semua titik stasiun. Indeks keanekaragaman dan indeks keseragaman tergolong rendah sedangkan indeks dominansi tergolong tinggi.
Keyword: Makrozoobentos, struktur komunitas, substrat

Judul: Status Ekologi Perairan Berdasarkan Makrozoobentos dengan Pendekatan Kurva ABC di Pantai Kupang, Desa Lubuk Damar, Kecamatan Seruway, Aceh Tamiang
Abstrak: Pantai Kupang, Desa Lubuk Damar, Kecamatan Seruway, Aceh Tamiang berpotensi mendapatkan gangguan ekosistem perairan karena berbagai aktivitas masyarakat di sekitar Pantai. Penelitian ini bertujuan untuk menganalisis status ekologi perairan menggunakan makrozoobentos berdasarkan kurva ABC. Penelitian dilaksanakan pada Bulan Agustus 2017 dan Januari 2018 di Pantai Kupang. Data yang dikumpulkan berupa kelimpahan makrozoobentos, substrat dan beberapa parameter kualitas air. Kepadatan makrozoobentos bulan Januari lebih tinggi dibandingkan dengan bulan Agustus. Secara umum hasil kurva ABC pada bulan Agustus maupun Januari menggambarkan bahwa adanya gangguan ekosistem perairan (kategori sedang) terhadap kehidupan makrozoobentos. Nilai indeks ekologi dan kurva ABC yang didapatkan berdasarkan kondisi makrozoobentos mengindikasikan bahwa Pantai Kupang telah mengalami gangguan ekosistem perairan yang tergolong sedang.
Keyword: Indeks ekologi, kurva ABC, makrozoobentos, Pantai Kupang

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