Judul: Kajian bioekologi udang putih (Penaeus merguiensis de Man)
Abstrak: White shrimp abundance is greatly influenced by food availability, existence of predators and competitors, as well as by characteristics of mangrove habitat. Changes in habitat quality in mangrove ecosystem directly affects the growth of this biota. The objective of the research were to determine suitable habitat characteristics of white shrimp based on maturity stage, and to determine spawning peak season and recruitment of white shrimp in mangrove ecosystem of Percut Sei Tuan North Sumatera. White shrimp habitat characteristics was evaluated based on biophysical and chemical parameters of environment at each station using principal component analysis. Spatio-temporal distribution was evaluated based on gonads maturity index using correspondence analysis. Temporal distribution of female white shrimp was evaluated based on the maturity of gonads in each observation month. Correlation analysis of white shrimp spatial distribution with size, sex, gonads maturity, and mangrove species at each station/zone was also performed. Principal component analysis results described that correlation between parameters centered on two main axes, each explaining 76.27% and 17.62% of total range. The analysis classified three groups of individuals/station. Group I consisted stations 1, 2, and 3 characterized by dissolved oxygen, nitrate, phosphate, current speed, and clay substrate. Group II consisted stations 4 and 5 characterized by mangrove density, litter production, plankton abundance and macrozoobenthos, and high litter decomposition rates. Group III consisted of six stations characterized by water temperature, brightness, depth, salinity, pH, and high sand substrate. Analysis of white shrimp spatial distribution based on gonads maturity level using correspondence analysis showed information which centered on two main axes, each explaining 65.17% and 28.60% of total range. Analysis results also showed female adult white shrimps with mature gonads were found in waters which have temperature 29.00°C - 30.5°C, salinity 31‰ - 31.20‰, and pH 7.05 - 7.40. Spawning peak season of white shrimp in Mangrove Ecosystem of Percut Sei Tuan in June and January, and recruitment between September and October, as well as February and March.
Keyword: White Shrimp, Penaeus merguiensis, spatio-temporal distribution, mangrove ecosystem

Judul: Keanekaragaman udang air tawar pada berbagai tipe habitat di Provinsi Jambi
Abstrak: The freshwater shrimp can be found in Indonesia Indonesia is consisted of families Atyidae and Palaemonidae of the order Decapoda. The main barrier factors influencing the presence of freshwater shrimp include habitat characteristics and environmental quality in each habitat type. Jambi Province, including the areas with lowland tropical rainforest has the highest deforestation rate in the Asian region. Effects of changes in forest conversion to agricultural habitats will change the ecosystem conditions. It is thought to affect macroinvertebrate diversity therein. The purpose of this research is to study the diversity of the river freshwater shrimp found in oil palm plantation, rubber plantation, community forest and secondary forest in relation to the convertion of forest and to clarify the species through DNA barcoding. The shrimps were collected from two locations, i.e. Batanghari and Sarolangun Regencies. The collection of the freshwater shrimps were conducted in four habitat types, i.e oil palm plantation, rubber plantation, community forest, and secondary forest. The research locations were chosen purposively and continued road sampling. Samples were taken by using a hand net and fish trap. Specimens’ identification were based on Wowor et al. 2004 and Cai et al. 2007. The environmental factors observed velocity (m/second),depth (cm), brightness (cm), temperature (°C), pH and substrate type. To see the effect of forest conversion to the diversity freshwater shrimp were analysed with Kruskal-Wallis non-parametric analysis continued with Multiple Comparisons. The relationship of the distribution of the freshwater shrimp were tested with Canonical Correspondence Analysis. Community structure were analysed with calculated diversity indexs, the eveness, and the similarity of habitats by using Primer 5 program. The study revealed six spesies of freshwater shrimp consisted of Macrobrachium malayanum, M. pilimanus, M. lanchesteri, Caridina malayensis, C. propinqua, C. excavatoides. Macrobrachium malayanum. Highest amount of diversity and evenness in Batanghari Regencies found in the oil palm plantation (H '= 0.934) and community forests (E = 0.934). Analysis of habitat similarities between habitats showed that oil palm and rubber plantations have similar habitat types, and different people in the forest habitat.... The freshwater shrimp diversity and eveness in Batanghari found high in the oil palm plantation (H’=1.148) and community forest (E=0.934). Analysis of habitat similarity between habitat oil palm plantations and rubber plantations have similar habitat type, and different in community forest. The freshwater shrimp diversity and eveness in Sarolangun found high in the secondary forest (H’=0.699) and community forest (E=0.6909). Analysis of habitat similarity between habitat community forest and rubber plantations have similar habitat type, while secondary forest habitat have similar with oil palm plantation. Based on the analysis of Canonical Analysis corespondance that environmental factors affecting the distribution of certain shrimp. This is shown in Batanghari Regencies , Macrobrachium lanchesteri distribution was affected by the altitude, width and pH. Caridina malayensis, C. excavatoides and C. propinqua distribution was affected by temperature and pH. Distribution of M. pilimanus and M. malayanum was affected by velocity and brightness. At the Sarolangun Regencies, distribution M. malayanum was affected by pH and temperature, while the distribution of M. lanchesteri was affected by pH and brightness. Based on the analysis
Keyword: diversity, freshwater shrimp, Macrobrachium, Caridina, DNA Barcode

Judul: Formulasi Algoritme Operasi Grup Jacobian Kurva Hyperelliptic ...
Abstrak: Dalam geometri aljabar, kurva hyperelliptic merupakan bentuk umum dari kurva elliptic. Kurva ini apabila dikenakan pada suatu lapangan berhingga akan membentuk suatu grup siklik. Pada kriptografi, khususnya enkripsi kunci publik, grup siklik yang dibangkitkan oleh kurva elliptic sudah banyak diteliti. Bahkan untuk kurva ini sudah memiliki standar oleh National Institute of Standard and Technology (NIST) Amerika. Sedangkan, untuk grup yang dibangkitkan oleh kurva hyperelliptic masih memiliki kekurangan dalam hal komputasinya. Tujuan dari penelitian ini adalah mengkonstruksi suatu lapangan berhingga pada , memilih kurva hyperelliptic atas lapangan hingga yang memenuhi kriteria keamanan untuk kriptografi, dan membuat formulasi operasi grup kurva hyperelliptic menggunakan algoritme Cantor. Dalam merekonstruksi lapangan hingga, terlebih dahulu tentukan dimensi dari lapangan hingga tersebut dan polinomial tak-teruraikan. Kemudian dipilih kurva hyperelliptic atas lapangan tersebut. Pada penelitian ini, kurva yang dipilih adalah = + + dengan lapangan hingga . Berdasarkan kurva yang dipilih, akan dibentuk suatu operasi grup dengan menggunakan algoritme Cantor, sehingga menjadi lebih aritmatik. Eksplorasi kurva hiperelliptic dilakukan untuk mengetahui keamanan dari kurva yang dipilih. Dengan menyusun algoritme operasi grup dari kurva yang dipilih, diperoleh perhitungan yang lebih aritmatik dan dapat diimplementasikan pada kriptografi kunci publik. Dari segi keamanan kurva telah memenuhi standar sehingga tahan terhadap serangan-serangan seperti Poligh-Hellman, Polard- , ataupun Frey-Ruck secara teorema.
Keyword: algoritme Cantor, kriptografi, kunci publik, kurva hyperelliptic, operasi grup