Judul: Nisbah Kelamin dan Perkembangan Gonad Beberapa Jenis Ikan di Sungai Surabaya.
Abstrak: Sungai Surabaya mendapat masukan limbah dari berbagai kegiatan yang diduga mengandung bahan pencemar Endocrine Disrupting Compounds (EDCs) yang dapat menyebabkan gangguan reproduksi pada ikan. Penelitian ini bertujuan untuk menganalisis kondisi nisbah kelamin dan status perkembangan gonad beberapa jenis ikan yang terdapat di sungai Surabaya. Penelitian ini dilaksanakan dari bulan Juli sampai November 2017 di Sungai Surabaya dan pengambilan contoh dilakukan pada bulan Juli, September dan Oktober. Hasil analisis nisbah kelamin tidak menunjukkan ketidaknormalan nisbah kelamin pada masingmasing ikan. Gonad ikan mengalami perkembangan dengan ditemukannya empat dari lima tingkat kematangan gonad dan lebih banyak ditemukan gonad yang belum matang. Ukuran pertama kali matang gonad ikan nila merupakan ukuran terkecil dibandingkan dengan jenis lainnya. Senyawa estradiol-17β tidak terdeteksi dalam penelitian ini. Tingkat pencemaran EDCs di Sungai Surabaya tidak menyebabkan ketidaknormalan nisbah kelamin namun menyebabkan penghambatan perkembangan gonad.
Keyword: EDCs, pencemaran, reproduksi, sungai

Judul: Endocrine Disrupting Chemicals (EDC) pada Komunitas Ikan di Sungai Brantas, Surabaya, Jawa Timur.
Abstrak: Sungai Brantas merupakan sungai terpanjang di Jawa Timur dengan panjang 320 km dan luas 12000 km2. Peningkatan jumlah aktivitas penduduk menyebabkan tingginya beban limbah di suatu perairan yang berasal dari kegiatan industri rumah tangga, rumah sakit, dan kegiatan pertanian yang berpengaruh terhadap kualitas airnya. Pencemaran yang terjadi pada biota ikan karena proses bioakumulasi di perairan. Tujuan penelitian ini untuk menentukan tingkat pencemaran EDC yang dapat mempengaruhi keberlanjutan hidup ikan. Penelitian ini dilakukan pada bulan Juli sampai November 2017 dengan dua stasiun yaitu daerah Karah (Stasiun I) dan Gubeng (Stasiun II) di Sungai Brantas Surabaya. Total ikan contoh yang diambil sebanyak 420 ekor. Uji kandungan EDC pada daging ikan menggunakan metode GC-MS. Jenis ikan yang banyak terakumulasi adalah ikan nila. Jenis EDC yang melebihi baku mutu pada tubuh ikan adalah pestisida klorpirifos. Kadar senyawa EDC yang paling tinggi terjadi pada musim kemarau.
Keyword: Bioakumulasi, ikan, toksik, Sungai Brantas

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