Judul: Sebaran Vegetasi Mangrove dan Keterkaitannya dengan Karakteristik Lingkungan Perairan Pesisir Makassar, Sulawesi Selatan.
Abstrak: Mangrove memiliki kemampuan hidup dalam beradaptasi dengan lingkungan pasang surut di wilayah pesisir. Pertumbuhan dan perkembangan mangrove dipengaruhi oleh karakteristik fisika dan kimiawi perairan. Penelitian dilakukan pada tiga stasiun menggunakan transek garis sebanyak tiga kali ulangan dalam satu stasiun. Pengambilan data kualitas lingkungan perairan dilakukan setiap satu sub stasiun dengan tiga kali ulangan masing-masing stasiun. Analisis hubungan sebaran vegetasi mangrove dan keterkaitannya dengan karakteristik lingkungan dilakukan menggunakan metode Analisis Komponen Utama dan Analisis Koresponden. Pada lokasi penelitian ditemukan lima jenis mangrove, Avicennia marina, Aegiceras corniculatum, Rhizophora apiculata, Rhizophora mucronata, dan Sonneratia alba dengan kerapatan berkisar antara 22-1322 ind ha- 1. Jenis A. marina dapat tumbuh pada substrat lempung sedangkan R. mucronata pada substrat lempung berliat. A. corniculatum dapat tumbuh dengan kondisi salinitas dan pH sedimen yang rendah.
Keyword: Kondisi Lingkungan, Mangrove, Vegetasi

Judul: Tipologi Ekosistem Mangrove Berdasarkan Karakteristik Lingkungan Perairan di Pesisir Banda Aceh, Provinsi Aceh
Abstrak: Mangrove memiliki tipe pertumbuhan yang unik sebagai bentuk adaptasi dari lingkungan pasang surut. Mangrove sangat rentan tumbuh pada habitat yang memiliki limbah perairan yang tidak baik. Penelitian ini bertujuan mengetahui tipologi ekosistem mangrove berdasarkan karakteristik lingkungannya. Penelitian ini dilakukan pada Maret sampai April 2018 dengan lima stasiun penelitian yang dapat mewakili ekosistem mangrove di Pesisir Banda Aceh, Provinsi Aceh. Metode pengambilan data ekosistem mangrove menggunakan teknik pengambilan contoh berbasis transek plot. Ada 7 vegetasi mangrove yang ditemukan di stasiun penelitian yaitu R. mucronata, R. apiculata, A. marina, A. rumphiana, A. officinalis, A. alba, dan K. candel. Analisis vegetasi mangrove meliputi kerapatan jenis, kerapatan relatif jenis, frekuensi jenis, frekuensi relatif jenis, penutupan jenis, penutupan relatif jenis, indeks nilai penting, dan Correspondence analysis (CA) untuk mengetahui keterkaitan antara karakteristik lingkungan dengan stasiun penelitian. Vegetasi mangrove dapat dilihat dengan indeks nilai penting. Hasil analisis perhitungan menunjukkan adanya perbedaan nilai indeks penting di stasiun penelitian. Diperoleh indeks nilai penting tertinggi pada tingkat pohon ditemukan R. mucronata di stasiun 5 yaitu (255.17), indeks nilai penting tertinggi pada tingkat anakan ditemukan R. mucronata di stasiun 2 (267.59), dan indeks nilai penting tertinggi pada tingkat semai ditemukan R. mucronata di stasiun 5 (200).
Keyword: adaptasi, indeks nilai penting, karakteristik lingkungan, vegetasi mangrove

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