Judul: Emisi Gas N2O dari Lahan Padi Sawah pada Berbagai Kondisi Lingkungan Mikro
Abstrak: Sawah yang selalu kering merupakan salah satu sumber emisi gas N2O. Tujuan penelitian ini adalah mengukur fluks gas N2O dari lahan padi sawah pada berbagai kondisi lingkungan mikro, dan menentukan rezim air yang optimum untuk mengurangi emisi gas N2O. Pengambilan data dilaksanakan selama satu musim tanam dimulai dari Maret sampai Juni 2015. Lokasi penelitian di Blok Sawah Patapaan Cikarawang, Kabupaten Bogor dan Laboratorium Ilmu Tanah Departemen Ilmu Tanah dan Sumberdaya Lahan, IPB. Penelitian dilakukan dengan tiga perlakuan rezim air yaitu tergenang (RT) untuk budidaya konvensional, basah (RB), dan kering (RK) untuk budidaya dengan System of Rice Intensification (SRI). Pengukuran emisi gas N2O dilakukan seminggu sekali sekaligus pengukuran parameter pH dan Eh tanah. Kemudian dilakukan perhitungan total fluks gas N2O dan dibandingkan antara tiga perlakuan tersebut. Total fluks gas N2O yang dihasilkan yaitu 308.53 mg/m2/musim (RT), 317.99 mg/m2/musim (RB), dan 613.53 mg/m2/musim (RK). Rezim air optimum dalam mereduksi gas N2O adalah rezim tergenang (RT).
Keyword: gas N2O, lahan padi, lingkungan mikro, rezim air

Judul: Analisis Sensitivitas Lingkungan Mikro yang Berpengaruh pada Emisi Gas N2O dari Lahan Padi Sawah
Abstrak: N2O yang teremisikan ke atmosfer lebih kecil daripada CO2 namun menyebabkan efek pemanasan global yang lebih tinggi daripada CO2 atau CH4. Tujuan dari penelitian ini adalah mengidentifikasi hubungan dan pengaruh faktor lingkungan mikro terhadap fluks emisi gas N2O dengan metode rank spearman. Rezim air yang diterapkan meliputi rezim air tergenang, rezim air basah, dan rezim air kering. Hasil penelitian menunjukkan rezim tergenang memiliki total fluks gas N2O sebesar -18.249 mg/m2/musim. Rezim basah memiliki total fluks gas N2O sebesar 62.794 mg/m2/musim, sedangkan pada rezim kering total fluks gas N2O sebesar 307.950 mg/m2/musim. Faktor lingkungan mikro yang memiliki korelasi paling besar terhadap fluks N2O adalah daya hantar listrik dan suhu tanah dengan nilai rank spearman (Rs) sebesar 0.3. Faktor pH, Eh dan kelembaban tanah memiliki Rs masing-masing sebesar 0.21, 0.18 dan 0.1. Faktor lingkungan yang paling sensitif pada penelitian ini terhadap fluks gas N2O adalah nilai pH pada rezim basah saat fase pertumbuhan vegetatif dengan nilai Rs pada fase ini sebesar 0.929.
Keyword: analisis sensitivitas, emisi N2O, korelasi rank spearman, lahan padi

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