Judul: Kelarutan N-NH4 dan N-NO3 dari kombinasi pupuk urea-zeolit pada tanah sawah inceptisol Ciomas dan vertisol Ciranjang
Abstrak: Nitrogen merupakan salah satu unsur hara makro yang paling dibutuhkan untuk pertumbuhan tanaman. Pupuk N yang paling sering digunakan di tanah tropik seperti di Indonesia adalah urea. Namun, penggunaan pupuk N ini sangat tidak efisien dan cenderung mudah hilang dari sistem tanah. Telah banyak produsen pupuk yang bermaksud untuk meningkatkan efisiensi dari pupuk N dengan menjadikannya pupuk lambat tersedia, salah satu caranya yaitu dengan mencampurkan bahan amelioran seperti zeolit yang memiliki nilai KTK tinggi.
Keyword: 

Judul: Nitrogen tersedia dan produksi jagung dengan perlakuan zeolit, kompos, kapur dan terak baja
Abstrak: Penelitian ini dilatarbelakangi rendahnya produktivitas lahan yang menjadi kendala usaha perluasan areal baru. Tujuan penelitian untuk mengevaluasi pengaruh pemberian zeolit dan kombinasinya dengan kompos, kapur dan terak baja, disamping membandingkan pengaruh penggunaan kapur dan terak baja. Penelitian dilakukan di lahan percobaan Fakultas Peternakan IPB di Jonggol dan Laboratorium Mahasiswa Jurusan Tanah, Fakultas Pertanian IPB. Penelitian dilaksanakan bulan april sampai dengan Nopember 1995. Perlakuan diberikan 2 minggu sebelum tanam, meliputi zeolit Cikembar dengan dosis 10 ton/ha, kompos kotoran sapi 10 ton/ha, kapur 5 ton/ha, terak baja Krakatau Steel 5 ton/ha. Perlakuan berupa interaksi zeolit kompos, diberikan dalam bentuk kompos zeolit. Pupuk dasar yang diberikan 150 kg N/ha (0.8 kg Urea/plot), 100 kg P/ha (1.25 kg TSP/plot) dan 100 kg K/ha (0.50 kg KCL/plot). Pupuk diberikan sa'at penanaman dalam larikan dipinggir lajur tana- man. Pengukuran dilakukan pada 10 tanaman contoh yang diambil secara acak 1 meter dari pinggir. Pemanenan 1 meter dari samping...dst
Keyword: 

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