Judul: Struktur Komunitas Makrozoobentos di Sungai Donan, Segara Anakan Bagian Timur, Cilacap, Jawa Tengah
Abstrak: Kegiatan antropogenik di sekitar sungai Donan dan perairan Segara Anakan bagian timur dapat menghasilkan limbah. Hal tersebut dapat menyebabkan penurunan kualitas air, sehingga mengganggu kehidupan organisme di perairan. Tujuan penelitian ini adalah menganalisis kondisi perairan sungai Donan, Segara Anakan bagian timur berdasarkan struktur komunitas makrozoobentos dan kualitas air. Kegiatan penelitian dilaksanakan pada bulan Agustus 2015 sampai Januari 2016 di lima titik stasiun. Pengambilan contoh makrozoobentos dan sedimen menggunakan Ekman grab. Pengelompokkan stasiun pengamatan berdasarkan parameter kualitas air dan tipe substrat membentuk tiga kelompok stasiun. Makrozoobentos yang teridentifikasi terdiri atas dua filum (Moluska dan Annelida), tiga kelas (Gastropoda, Bivalvia, dan Polychaeta), dan 28 genera. Kelompok stasiun 2 memiliki rata-rata kepadatan makrozoobentos tertinggi, yaitu 25 Ind/m2. Struktur komunitas makrozoobentos yang ditemukan memiliki keanekaragaman tinggi dengan sebaran individu merata pada tiap jenisnya dan tidak terjadi dominansi.
Keyword: macrozoobenthos, sediment, water quality

Judul: Struktur Komunitas Makrozoobentos dan Keterkaitannya dengan Kualitas Air di Segara Anakan Bagian Timur dan Sekitarnya.
Abstrak: Kegiatan antropogenik di estuari Segara Anakan dapat menyebabkan penurunan kualitas air dan berdampak terhadap kehidupan makrozoobentos. Penelitian bertujuan untuk mendeskripsikan struktur komunitas makrozoobentos dan kaitannya dengan kualitas air sebagai dasar kegiatan pengelolaan di Segara Anakan bagian timur dan sekitarnya. Penelitian dilakukan sejak Maret hingga Juli 2017 di perairan Segara Anakan. Analisis dilakukan untuk menentukan kepadatan, indeks ekologi, dan korelasi Spearman. Dari sampel yang diperoleh, ditemukan 7 kelas, 29 famili, dan 35 genus makrozoobentos. Rata-rata kepadatan, indeks keanekaragaman, indeks keseragaman, dan indeks dominansi pada stasiun pengamatan berturut-turut berkisar antara 165-1.056 ind/m2, 0,64-2,16, 0,29-0,90, dan 0,28-0,76. Tingkat keanekaragaman tergolong rendah dengan tingkat dominansi spesies yang cukup tinggi. Polychaeta, Malacostraca, dan Sipunculidae memiliki korelasi positif dengan C-Organik dan berkorelasi negatif dengan kekeruhan. Gastropoda memiliki korelasi negatif dengan salinitas, TDS, dan kedalaman.
Keyword: Indeks ekologi, makrozoobentos, Segara Anakan, struktur komunitas

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