Judul: The Sumatran Genus Morinda L. (Rubiaceae)
Abstrak: The major revision of the genus Morinda for the Sumatran region was undertaken by Miquel in 1856 and 1862 but there has no comprehensive revision of the genus recently. Therefore the revision of the genus in Sumatra was done based on their morphological characters, especially to know the species of Morinda and their distribution pattern. A phylogenetic analysis was also studied to establish the relationship among the species using parsimony analysis. The present study revealed that there were eight species, six species among them were previously known as M. citrifolia L., M. jackiana Korth., M. leparensis Valeton, M. rigida Miq., M. tomentosa Roth, M. umbellata L., and two newly proposed species namely M. lanuginosa Suratman and M. wongiana Suratman. M. bracteata Roxb. var. latifolia Valeton was also proposed as the new synonym of M. citrifolia L. var. bracteata (Roxb.) Hook.f. An identification key and detailed description of the taxa were provided. The natural history data including habitat, distribution, uses and vernacular names were also presented. The most widespread species is M. citrifolia while the other species have a limited distribution. The highest number of the species is found in North Sumatra and Bangka Belitung which consist of 4 species respectively. The phylogenetic analysis based on morphological data showed that despite their poorly resolved phylogenetic tree, Morinda is undoubtedly a monophyletic genus.
Keyword: 

Judul: Merremia dennstedt ex endlicher (Convolvulaceae) in Sumatra.
Abstrak: Merremia is a small genus in the family Convolvulaceae. Merremia is a perennial or annual herb or woody liana with stems creeping or twinning on trees or rocks, put out milky white sap when injured and some species with tubers. Merremia is often confused with genus Ipomoea, due to they have resemblance in funnel shaped or campanulate corolla and straight anther. Phenetically, some members of Merremia have yellow flower whereas Ipomoea has white, purple or purplish white. Merremia is also confused with Operculina due both have non-spinulose pollen and dehiscent capsule. Nevertheless, Operculina characterized by circumciselli capsule and Merremia characterized by valve capsule. The important character in Merremia is the spread of the hairs on corolla that can be easily observed at the mature flower bud. The genus Merremia is found in the tropical regions of both hemispheres. Merremia wildly distributed throughout the tropical regions of Asia, Africa, Australia, North and South America and approximately there were 80 species of Merremia in the world. A Total of 175 sheets (164 collection numbers) which are deposited in Herbarium Bogoriense, 97 sheets (95 collection numbers) which are deposited Andalas University Herbarium (ANDA) and 9 sheets (4 collection numbers) which are deposited in BIOTROP Herbarium (BIOT) were studied. It composed of all specimens of Merremia in Sumatra. Additional specimens were collected by the author 28 sheets (15 collection numbers) from North Sumatra, West Sumatra and Lampung, which are stored in BO and BIOT. The digital data that consist of type specimens and distributions of species from JSTOR Plant Science and Convolvulaceae Unlimited were also used here. All the hebarium specimens were studied based on their morphological characters following de Vogel (1987) and Rifai (1976). The terminology of morphological characters followed Lawrence (1955), Veldkamp (1987), Harris and Harris (1994), Hickey and King (2005) and Stearn (1983). Information on the habitat, ecology, distribution, vernacular names and uses were noted from the specimens label and literatures. Taxonomic studies in Sumatra were conducted. There are eight species, one subspecies, one varietas and two forma from nine previously species (M. cissoides, M. dissecta, M. emarginata, M. hirta, M. peltata, M. quinquefolia, M. tridentata, M. tuberosa and M. vitifolia), two subspecies (M. umbellata ssp. orientalis and M. tridentata ssp. hastata), one varietas (M. boisiana var. sumatrana) and two forma (M. hederacea f. pubescens and M. hederacea f. barbata) can be recognized. One species (M. tridentata) and subspecies (M. tridentata ssp. hastata) are excluded because they have been proposed to different new taxa Xenostegia by Austin and Staples. The existence of M. emarginata was noted as new record in Sumatra and M. cissoides was noted as new record in Indonesia. A phylogenetic analysis using PAUP*4.Ob10 was undertaken based on morphological characters, using Evolvulus nummularius and Porana volubis as the out group. The phylogenetic analysis used 35 morphological characters was resulted consistency index (CI) = 0.60, homoplasy index (HI) = 0.40, retention index (RI) = 0.56 and Rescaled consistency index (RC) = 0.34. Phylogenetic tree used morphological characters divided taxa into two groups. The separation support M. boisiana var. sumatrana, M. cissoides, M.
Keyword: Convolvulaceae, Merremia, morphology, phylogenetic, Sumatra

Judul: Implementasi Algoritme Enkripsi Advanced Encryption Standard secara Paralel dengan GPU NVIDIA CUDA
Abstrak: Processor streaming architecture in GPU has provide general purpose computation which have its own potential to help CPU with its parallel computation capability. One example of supported processor streaming architecture is Fermi which is developed by NVIDIA. Furthermore, NVIDIA has developed its own software development kit namely CUDA, which can integrate many popular existing programming languanges such as C++ for GPU-based parallel computation. This research focus on the implementation of parallel AES algorithm with GPU and analyze the performance result of the implementation in two different NVIDIA devices, namely NVIDIA GeForce GT220 and NVIDIA Quadro 600. In general, the performance of parallel GPU computation is better than sequential computation for large data input. It is obtained that the maximum speedup of NVIDIA GeForce GT220 in 8 MB input is 89.3 with 180% efficiency. Higher speedup of 101.6 can be obtained by NVIDIA Quadro 600 with the same input size with around 100% efficiency.
Keyword: