Judul: Keanekaragaman Jenis dan Sebaran Spasial Amfibi di Suaka Margasatwa Nantu Gorontalo dan Sekitarnya
Abstrak: Nantu Wildlife Reserve area is one of tropical remnant forest in Sulawesi, a part of Wallaceae bioregion. Nantu Wildlife Reserve was established especially to conserve babirusa, and therefore amphibians data is not available yet. Objectives of the research were to identify types of habitat and species diversity of amphibians in Nantu Wildlife Reserve and its surrounding areas. Data were collected on 14th to 27th of June 2013. Observations were made at seven locations focusing on the east area of the Nantu Wildlife Reserve. Species data were collected using Visual Encountering Survey (VES) combined with Time Search methods. During observation, 4 families were found consisted of 17 species. A map of the spatial distribution of amphibians showed that there was species composition differences among four types of habitats (fields, gardens, low disturbed forest, undisturbed forest). Family of Dicroglossidae was the most common family. There was a clear distinction composition of amphibians between the of amphibians in forest areas with areas that have been cultivated/disturbed by humans.
Keyword: Sulawesi, Nantu Wildlife Reserve, diversity, amphibian

Judul: Komunitas Amfibi di beberapa Sungai pada Suaka Margasatwa Nantu Provinsi Gorontalo
Abstrak: Amfibi merupakan salah satu satwa yang hidup tidak jauh dari sumber air. Keberadaan amfibi sangat dipengaruhi oleh kondisi dan tipe habitat dimana beberapa jenis dapat ditemukan di hutan rendah gangguan atau di hutan terganggu. Penelitian ini dilakukan di beberapa sungai pada Suaka Margasatwa Nantu untuk mengidentifikasi komposisi jenis amfibi, pemilihan mikrohabitat oleh amfibi, dan pola penyebaran amfibi. Pengukuran mikrohabitat dilakukan untuk mendapatkan data mengenai kecepatan arus, kedalaman sungai, tutupan kanopi, lebar sungai, dan jenis substrat. Hasil penelitian menemukan 490 ekor katak dari 15 jenis amfibi tergolong dalam empat famili. Limnonectes cf modestus merupakan jenis yang selalu ditemukan di semua sungai dengan kelimpahan tertinggi (519 individu/ha) di hutan sekunder. Habitat sungai di hutan primer dan hutan sekunder memiliki kesamaan komunitas amfibi paling tinggi (86.6%), sedangkan komunitas amfibi pada sungai di kebun tebu paling berbeda dengan sungai lainnya. Analisis menunjukkan bahwa jenis amfibi cenderung memilih kondisi mikro habitat tertentu, seperti Fejervarya limnocharis sangat erat hubungannya dengan kondisi sungai yang sangat lebar dengan tutupan kanopi terbuka. Amfibi di sungai umumnya menyebar secara mengelompok.
Keyword: komposisi jenis amfibi, mikrohabitat, pola penyebaran

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