Judul: Abundance of Sponges on Reef Ecosystems in Dampier Strait, Raja Ampat
Abstrak: Selat Dampier merupakan salah kawasan konservasi perairan Raja Ampat, bagian coral triangle. Kondisi terumbu karang di Selat Dampier termasuk dalam kondisi yang baik. Spons termasuk filum porifera yang bersifat sessile dan filter feeder. Komunitas spons dapat menjadi salah satu bioindikator. Secara ekologis, spons merupakan salah satu biota penyusun ekosistes terumbu karang. Tujuan dari penelitian ini adalah mengetahui kelimpahan spons yang berada di Selat Dampier dengan menggunakan metode Underwater Photo Transect (UPT). Kondisi terumbu karang pada Selat Dampier tergolong cukup baik (30,29%) dan didominasi oleh tutupan karang keras. Hasil identifikasi spons didapatkan 506 individu dari 93 spesies, 66 genus, 41 famili, dan tiga kelas. Demospongia merupakan kelas paling sering dijumpai. Famili yang paling banyak ditemukan adalah Chalinidae dengan total individu 56. Selain itu, Chalinidae merupakan famili dengan spesies terbanyak, yaitu delapan spesies. Aaptos suberitiodes adalah spesies dengan total individu terbanyak, yaitu 35 individu. Hasil correspondence analysis menunjukkan adanya asosiasi antara komunitas spons dengan tutupan karang keras dan rubble., Dampier Strait is one of the water areas of Raja Ampat, included the coral triangel. The condition of coral reefs in Dampier Strait is good condition. Sponges are phylum Porifera which are sessile and filter feeder. Sponge communities can be one of the bioindicator. Ecologically, sponges are one of the constituent biota of reef ecosystems. The objective of this study is determine the abundance of sponges in Dampier Strait using the Underwater Photo Transect (UPT) method. The condition of coral reefs in the Dampier Strait is quite good (30,29%) and dominated by hard corals. The results of sponge identification are 506 individuals from 93 species, 66 genera, 41 families, and three classes. Demospongia are the classes most often found. The most common family found is Chalinidae with a total of 56 individuals. Moreover, Chalinidae is the family with the most species, which is eight species.Aaptos suberitiodes is the species with the largest total number of individuals studied, 35 individuals. The results of correspondence analysis show an association between sponge communities with hard coral and rubble cover.
Keyword: abundance, Dampier Strait, coral reefs, sponge

Judul: Identification of Sponge Species Based on Morphology and Genetics in Raja Ampat, West Papua
Abstrak: Invertebrata laut termasuk kelompok hewan tidak bertulang belakang yang berperan dalam menjaga kestabilan ekosistem laut. Banyak spesies invertebrata laut yang belum teridentifikasi, salah satunya biota spons. Keberadaan spons tidak banyak diapresiasi, dipelajari dan diteliti dengan baik dibandingkan dengan biota laut lainnya. Beberapa penelitian terkait spons paling banyak dilakukan di wilayah Jawa dan Sulawesi. Penelitian terkait genetik dan tipe spikula tidak banyak dilakukan di Perairan Indonesia. Kesulitan identifikasi morfologi dan taksonomi menjadi salah satu faktor minimnya informasi terkait data spons. Tujuan penelitian ini yaitu mengetahui jenis-jenis spons yang ada di perairan Raja Ampat berdasarkan tipe spikula dan genetik. Identifikasi spesies berdasarkan genetik dilakukan dengan BLAST (Basic Local Alignment Search Tool) pada Genbank di NCBI (National Centre For Biotechnology Information) menggunakan data sekuen yang diperoleh dari sampel setelah melalui tahapan ekstraksi, PCR, elektroforesis, dan sekuensing. Rekonstruksi pohon filogeni dibuat menggunakan model Kimura 2-parameter dengan metode Neighbour Joining dan Maximum Parsimony. Identifikasi bentuk spikula spons dilakukan dengan pengamatan preparat menggunakan mikroskop majemuk. Berdasarkan analisis laboratorium dari 22 sampel ditemukan 5 sampel terdeteksi sebagai spesies spons Halichondria sp., Stylissa carteri, Xestospongia deweerdtae, dan Theonella sp. Rekonstruksi pohon filogeni menghasilkan empat clade besar. Bentuk tipe spikula yang teramati terdiri dari spikula monoaxon dan tetraxon., Marine invertebrates are a group of invertebrate animals that play a role in maintaining the stability of marine ecosystems. Many marine invertebrate species have not been identified, one of which is the sponge. The existence of sponges is not much appreciated, studied and well researched compared to other marine biota. Most research related to sponges has been carried out in Java and Sulawesi. Research related to genetics and spicule types is not much carried out in Indonesian. The difficulty of identifying morphology and taxonomy is one of the reasons for the lack of information related to sponge data. The purpose of this study was to determine the types of sponges in Raja Ampat based on the type of spicules and genetics. Genetic identification of species was carried out using BLAST (Basic Local Alignment Search Tool) on Genbank at NCBI (National Center For Biotechnology Information) using sequence data obtained from samples after going through the stages of extraction, PCR, electrophoresis and sequencing. Phylogenetic tree reconstruction was made using the Kimura-2 parameter model with the Neighbor Joining and Maximum Parsimony methods. Identification of the shape of sponge spicules was carried out by observing the preparations using a compound microscope. Based on laboratory analysis of 22 samples, it was found that 5 samples were detected as Halichondria sp., Stylissa carteri, Xestospongia deweerdtae, and Theonella sp. Phylogenetic tree reconstruction resulted in four large clades. The types of spicules observed consisted of monoaxon and tetraxon spicules.
Keyword: DNA barcoding, genetic, spicule, sponge

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