Judul: Pengaruh bahan pemantap tanah (Soil Conditioner) terhadap beberapa sifat fisik dan penetrasi akar padi gogo IR-36 pada tanah podsolik merah kuning (Typic Humitropept) dari Jasinga
Abstrak: Tujuan Penelitian ini adalah untuk mengamati pengaruh bahan pemantap tanah (soil conditioner) terhadap sifat- sifat fisik tanah, seperti bobot isi, distribusi ukuran pori, Angka Atterberg, nilai COLE, kemantapan agregat, dan kekuatan tanah, serta melihat pengaruhnya terhadap penetrasi akar Padi Gogo IR-36. Percobaan dilakukan di Rumah Kaca, Jurusan Tanah pada akhir Oktober 1987 akhir Januari 1988. Analisis sifat fisik tanah dilakukan di Laboratorium Fisika Tanah, Jurusan Tanah, Fakultas Pertanian, IPB; dan Laboratorium Konservasi Tanah dan Air, Pusat Penelitian Tanah. Analisis sifat ini dimulai dari awal Februari sampai April 1988. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap. dijelaskan sbb: Perlakuan bahan pemantap tanah dapat a (kontrol), b (S1 Semen dengan dosis 2 ton/ha), c (S2 = Semen dengan dosis 7 ton/ha), d (21 = Zeolit dengan dosis 15 ton/ha), e (Z2 = Zeolit dengan dosis 30 ton/ha), ₤ (K1 Sampah kota dengan dosis 10 ton/ha), g (K2 = Sampah kota dengan dosis 15 ton/ha), h (P1 = Kotoran ayam dengan dosis 10 ton/ha), i (P2 = Kotoran ayam dengan dosis 15 ton/ha). Jumlah perlakuan seluruhnya sebanyak 9 perlakuan. Percobaan ini diulang 3 kali, sehingga jumlah keseluruhan satuan percobaan 27 buah. Pemberian bahan pemantap tanah tidak nyata mempengaruhi bobot isi, pori drainase sangat cepat dan lambat, air tersedia, aerasi tanah, kekuatan tanah, dan penetrasi akar Padi Gogo IR-36. ...
Keyword: 

Judul: Pengaruh residu kapur, kompos dan beberapa pupuk P terhadap pertumbuhan jagung (Zea mays L.) dan sifat-sifat kimia tanah podsolik merah kuning (Typic hapludult) dari Jasinga
Abstrak: Perkembangan ekonomi bersama pesatnya pertumbuhan penduduk telah mendesak pembangunan di bidang pertanian di Indonesia ke arah penggunaan tanah-tanah marjinal. Podsolik Merah Kuning merupakan salah satu jenis tanah marjinal yang penyebarannya sangat luas di Indonesia. Tanah ini merupakan tanah masam dan miskin unsur hara. Untuk meningkatkan produksi dalam usaha pertanian tanaman pangan, pada tanah-tanah masam perlu dilakukan pengapuran dan pemupukan serta pemberian bahan organik. Penelitian ini bertujuan untuk mengetahui pengaruh residu-residu kapur, kompos dan pemupukan P terhadap serapan P dan Ca tanaman, bobot kering tanaman serta sifat-sifat kimia pada tanah Podsolik Merah Kuning (Typic Hapludult) dari Jasinga. Penelitian dilakukan di rumah kaca dan laboratorium Jurusan Tanah, Fakultas Pertanian, Institut Pertanian Bogor. Pelaksanaan penelitian dilakukan sejak Desember 1995 sampai Maret 1996. Bahan-bahan yang digunakan dalam penelitian ini adalah pupuk dasar urea dan KCI serta tanaman indikator jagung varietas pioneer serta contoh tanah Podsolik Merah Kuning (Typic Hapludult) dari Jasinga yang telah ditanami jagung varietas arjuna (musim tanam pertama) serta diberi perlakuan pupuk fosfat dengan dosis 100 ppm P, masing-masing 1.180 g TSP/pot, 1.207 g PARP 50%/pot, dan 1.199 g PARP 70%/pot. Selain itu telah diberikan perlakuan pengapuran dalam Dentuk CaCO₃ berdasarkan kadar Al-dd yaitu: 0 g/pot (0% Al-dd), 7.36 g/pot (50% Al-dd), 14.72 g/pot (100% Al-dd), dan 29.44 g/pot (200% Al-dd). Dan kompos yaitu dengan dosis 0 ton/ha (0 g/pot) dan 10 ton/ha (11.85 g/pot). Percobaan pada Denelitian ini merupakan lanjutan dari percobaan sebelumnya, dimana sebagian nasil dari percobaan sebelumnya digunakan sebagai data sekunder. ...
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