Judul: Pengaruh pemupukan nitrogen dan cara pengendalian gulma terhadap pertumbuhan nenes bogor
Abstrak: Percobaan ini bertujuan mengetahui pengaruh perbedaan taraf pemupukan nitrogen dan penggunaan berbagai cara pengendalian gulma serta interaksinya terhadap pertumbuhan nenas Bogor (Ananas comosus (L.) Merr.) klon Gati. Percobaan dilakukan di Kebun Percobaan IPB Sindangbarang, Bogor, dari bulan April 1983 sampai dengan bulan September 1984. Taraf pemupukan N yang dicoba adalah 15 g N/ tanaman dan 30 g N/tanaman (dalam bentuk urea; 46% N) yang diberikan pada saat tanam dan enam bulan kemudian, masing- masing setengah dosis. Pupuk dasar berupa 2 kg pupuk kandang/tanaman, 16,7 g TSP/tanaman dan 40 g ZK/tanaman diberi kan pada saat tanam. Cara pengendalian gulma yang dicoba adalah cara mekanik sederhana, cara kimia (dengan herbisida yang berbahan aktif campuran diuron dan paraquat) dan tanpa penyiangan. Percobaan disusun secara faktorial dalam Rancangan Acak Kelompok yang terdiri atas tiga kelompok. Pada tiap kelompok ada enam petak satuan percobaan yang berukuran 12 m x 1,6 m. Jumlah daun, tinggi tanaman dan jumlah anakan diamati tiap bulan dari 10 tanaman contoh dari pengacakan atas 24 tanaman tiap petak. Juga diamati tingkat pembungaan tanaman dan luas daun terpanjang saat inisiasi bunga. Gulma yang muncul dinilai tingkat penutupannya dan SDR gulma dominan (SDR nilai penyebaran dan dominansi gulma tertentu).
Keyword: 

Judul: Pengaruh pupuk nitrogen dan giberelin terhadap pertumbuhan vegetatif Nenas (Ananas comosus L.Merr) klon Pasir Kuda-1
Abstrak: Penelitian ini dilakukan untuk mempelajari pengaruh pupuk nitrogen dan giberelin serta interaksinya terhadap pertumbuhan tanaman nenas Klon Pasir Kuda-1. Penelitian ini dilaksanakan di Kebun Percobaan Pasir Kuda, Bogor pada bulan Maret – Juli 2010. Metode penelitian yang digunakan adalah Rancangan Kelompok Lengkap Teracak (RKLT) dua faktor. Faktor pertama adalah pupuk nitrogen dengan tiga taraf konsentrasi yaitu urea 0 g/l, 25 g/l dan 40 g/l. Faktor kedua adalah giberelin dengan tiga taraf konsentrasi 0 ppm, 25 ppm, dan 50 ppm. Tanaman nenas yang digunakan berasal dari stek basal daun mahkota yang berumur 7.5 bulan setelah tanam (BST). Aplikasi pupuk nitrogen dilakukan dua minggu sekali. Giberelin diaplikasikan setiap sebulan sekali. Aplikasi pupuk nitrogen dan giberelin dilakukan selama 4 bulan. Volume siram pupuk nitrogen dan giberelin adalah 30 ml/tanaman. Analisis data yang digunakan yaitu uji F. Jika hasilnya berbeda nyata maka dilakukan uji lanjut Tukey (BNJ) pada taraf 5%. Peubah yang diamati terdiri dari jumlah daun, panjang daun, lebar daun, tinggi tanaman, warna daun dan stomata daun.
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