Judul: Profil Stok Karbon di Area Ekosistem Mangrove Pulau Sangiang, Banten
Abstrak: Ekosistem mangrove memiliki kemampuan menyerap karbon dioksida (CO2) yang dapat membantu penurunan karbon dioksida antropogenik diudara yang dapat menyebabkan pemanasan global dan perubahan iklim. Penelitian ini bertujuan mengkaji stok karbon organik pada sedimen dan biomassa mangrove di Pulau Sangiang, Banten. Lokasi penelitian dibagi menjadi 3 area yaitu area dekat darat dan area dekat laut yang keduanya masih termasuk mangrove alami serta area restorasi. Metode yang digunakan yaitu perhitungan alometrik spesifik di biomassa dan pengukuran karbon organik di sedimen. Hasil menunjukkan presentase biomassa di Below Ground Biomass (BGB) lebih besar (69.58%) dibandingkan dengan di Above Ground Biomass (AGB) (30.42%). Stok karbon organik yang terbesar berada di sedimen dengan presentasi sebesar 58.13 % dari total stok karbon secara keseluruhan, diikuti stok biomassa pada BGB sebesar 29.11 % dan terendah pada AGB sebesar 12.76%. Total stok karbon berkisar antara 4679.32-11389.6 MgC ha-1 dengan rata-rata sebesar 8222.35 MgC ha-1.
Keyword: biomassa, restorasi mangrove, sedimen, stok karbon

Judul: Profil Stok Karbon di Area Konservasi Mangrove Segara Anakan, Kabupaten Cilacap, Jawa Tengah
Abstrak: Ekosistem mangrove di Indonesia merupakan ekosistem terluas di dunia yang berperan penting dalam menyerap karbon dari atmosfir. Namun, telah terjadi pengurangan luas mangrove akibat konversi fungsi lahan sehingga perlu dilakukan restorasi mangrove untuk mengembalikan fungsi alami tersebut. Penelitian ini bertujuan mengkaji stok karbon organik pada sedimen dan biomassa mangrove di area restorasi dan alami kawasan konservasi mangrove, Segara Anakan, Kabupaten Cilacap, Jawa Tengah. Lokasi penelitian dibagi menjadi 3 area yaitu area kanal, area dekat laut dan area restorasi. Metode yang digunakan yaitu perhitungan alometrik spesifik di biomassa dan pengukuran karbon organik di sedimen. Hasil menunjukkan persentase biomassa di AGB lebih besar (57.64%) dibandingkan dengan di BGB (42.36%). Persentase kadar karbon organik tertinggi berada di area restorasi dengan rata-rata sebesar 17.27 ±2.11%, diikuti area kanal sebesar 6.54 ±0.36% dan yang terendah area dekat laut sebesar 5.92 ±0.65%. Stok karbon organik yang terbesar berada di sedimen dengan persentasi sebesar 83.18 % dari total stok karbon secara keseluruhan, diikuti stok biomassa pada AGB sebesar 9.70 % dan terendah pada BGB sebesar 7.13 %. Secara keseluruhan total stok karbon berkisar antara 134.88 - 229.26 Mg C ha-1 dengan rata-rata sebesar 180.41 ± 47.28 Mg C ha-1.
Keyword: karbon organik, restorasi mangrove, sedimen mangrove, Segara Anakan

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