Judul: Pengaruh Umur Kayu Mangium (Acacia mangium Wild) dan Ampupu (Eucalyptus urophylla Blake) terhadap Rendemen dan Sifat Pulp Semi Kimia Sulfit Netral
Abstrak: Penelitian ini bertujuan untuk mempelajari pengaruh umur kayu Mangium (Acacia mangium Willd.) dan Ampupu (Eucalyptus urophylla Blake.) terhadap rendemen dan sifat pulp semi kimia sulfit netral, sehingga dapat diketahui umur tebang optimum dan konsentrasi natrium sulfit yang sesuai untuk setiap umur kayu agar diperoleh kualitas pulp terbaik untuk kertas medium. Perlakuan yang akan dilihat pengaruhnya tanam kayu (Faktor A) yang terdiri dari tiga adalah umur taraf untuk kayu Mangium (3, 4, dan 7 tahun) dan dua taraf untuk kayu Ampupu (5 dan 7 tahun), serta faktor konsentrasi natrium sulfit (Na2S03) yang terdiri dari tiga taraf untuk masing- masing jenis kayu (12, 14, dan 16 persen). Analisa yang dilakukan meliputi rendemen pulp, sulfur terikat, bilangan Kappa, serta analisa sifat fisik lembaran pulp yang meliputi indeks sobek, panjang putus, indeks retak, ketahanan lipat, ring crush, dan concora. ...
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Judul: Sifat pulp sulfat Acacia mangium Wild. pada beberapa  taraf umur dan konsentrasi alkali aktif berdasarkan analisis dimensi serat
Abstrak: Analisis keragaman data pengujian menunjukkan adanya pengaruh umur dan konsentrasi alkali aktif terhadap sifat fisikokimia pulp dengan pola hubungan yang berlawanan. Peningkatan umur kayu menyebabkan peningkatan rendemen pulp, konsumsi alkali, bilangan Kappa, indeks sobek, indeks retak, panjang putus, dan ketahanan lipat. Nilai parameter pengujian tersebut cenderung menurun dengan semakin meningkatnnya konsentrasi alkali aktif yang digunakan pada proses pemasakan kecuali untuk konsumsi alkali yang cenderung meningkat. Redemen pulp tertinggi untuk setiap taraf umur kayu adalah 50.17 persen untuk kayu 3 tahun, 50.44 persen untuk kayu 4 tahun, 52.32 persen untuk kayu 5 tahun, dan 52.81 persen untuk kayu 8 tahun. Pada kondisi optimal tersebut nilai bilangan Kappa meningkat dari 14.17 sampai 19.92 pada kisaran umur kayu 3 sampai 8 tahun. Konsumsi alkali pada proses pemasakan berkisar antara 12.56 sampai 15.99 persen. Identifikasi mutu lembaran pulp berdasarkan kriteria Misra menunjukkan kayu berumur 3, 4, dan 5 tahun memiliki skor lebih tinggi dibandingkan dengan kayu umur tahun 8 tetapi sifat fisik lembaran pulpnya relatif lebih rendah.
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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