Judul: Pengaruh penambahan CaCo3 dengan dosis 50-200mg/l pada media pemeliharaan terhadap pertumbuhan Cherax quadricarinatus
Abstrak: Cherax quadricarinatus nerupakan komoditas budidaya air tawar yang saat ini banyak diminati oleh masyarakt. Namun, produksinya masih terkendala dengan produktivitasnya yang rendah serta ukuran individu yang tidak seragam.
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Judul: Pengaruh penambahan CaCo3 dengan dosis 50-200 mg/l pada media pemeliharaan terhadap pertumbuhan Cherax quadricarinatus
Abstrak: Cherax quadricarinatus merupakan komoditas budidaya air tawar yang saat ini banyak diminati oleh masyarakat. Namun, produksinya masih terkendala dengan produktivitasnya yang rendah serta ukuran individu yang tidak seragam. Karakteristik yang senantiasa menyertai pertumbuhan pada golongan udang- udangan ialah proses molting. Permasalahan molting pada cherax ialah habitat hidupnya berada di perairan tawar yang kandungan kalsiumnya rendah, sehingga kurang mendukung pembentukan eksoskeleton. Peneltian ini bertujuan untuk mengetahui dosis CaCO3 sebagai sumber kalsium yang baik untuk pertumbuhan cherax. Penelitian dilakukan selama 60 hari, dengan menggunakan benih cherax (bobot 1,61±0,24 gram dan panjang 4,11±0,31 cm) sebanyak 105 ekor yang berasal dari Taufan Fish Farm, Bogor. Cherax dipelihara dalam 15 akuarium (60x30x35 cm, volume air 36 liter) dengan kepadatan 7 ekor / akuarium (40 ekor / m²). Perlakuan yang diberikan adalah pemberian larutan CaCO3 50 mg/liter, 100 mg/liter, 150 mg/liter dan 200 mg/liter. CaCO3 yang digunakan dilarutkan terlebih dahulu menggunakan H₂SO₄ dengan bahan aktif 95% dan konsentrasi 50% kapur CaCO3, setiap perlakuan diulang 3 kali. Selama pemeliharaan cherax diberi pakan 3% biomassa per hari, setengah dari media pemeliharaan diganti dengan cara disiphon untuk menjaga kualitas media. Pengukuran berat dan panjang tubuh dilakukan setiap 10 hari, jumlah ikan diamati setiap hari. Selain itu setiap 10 hari sekali dilakukan juga pengukuran kualitas air. Selama penelitian DO berkisar antara 5,40-6,30 mg/l, pH berkisar antara 6,40-7,30; Kesadahan Ca²+ berkisar antara 19,22-338,26 mg/l CaCO3, Kesadahan total berkisar antara 30,75-580,18 mg/l CaCO3 dan alkalinitas berkisar antara 8,00-104,00 mg/l CaCO3, sedangkan pada saat panen dilakukan pengukuran ammoniak (NH3) dengan nilai berkisar antara 0,0045-0,0424 mg/1. Cherax yang dipelihara mengalami pertumbuhan, namun pada setiap perlakuan nilai laju pertumbuhan tersebut berbeda-beda. Perlakuan pemberian larutan CaCO3 menghasilkan perbedaan pada laju pertumbuhan spesifik (P<0,05), pertumbuhan panjang (P<0,01) dan efisiensi pakan (P<0,05). Dosis CaCO3 yang terbaik ialah 100 mg/l yang menghasilkan laju pertumbuhan spesifik sebesar 2,89±0,49%, pertumbuhan panjang 3,73±0,91cm dan efisiensi pakan 92,04±9,04%. Sedangkan tingkat kelangsungan hidup tidak memberikan hasil yang berbeda nyata (P>0,05).
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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