Judul: Soil development of mine Tailings in ModADA PTFI : reclamation and natural sucession aspect
Abstrak: Tailings are residue of mining material after separation of valuable substances such as copper, gold and silver elements. Separation of these elements involves crushing of parent material to become fine particles and separation of the precious elements by flotation technique. Total amount of tailings produc ed by PT Freeport Indonesia are about 230.000 tons/day. These tailings are transported and deposited in the lowlands of Timika, Papua and confined in the two levees i.e East Levee and West Levee called as ModADA (Modified Ajkwa Deposition Area). The research had been done in ModADA, the property of PTFI in Timika, Papua from March to November 2005.
Keyword: Tailing ModADA, Reklamasi Tanah, Papua, Succession

Judul: Characterization and Soil Development on Reclaimed Coal Mine Land at PT Kaltim Prima Coal
Abstrak: Mining activities are part of economic development activities that utilize natural resources and are expected to guarantee the future life. Issues that will arise as a result of mining activity which may result in less negative impact on the environment are in the form of decreased soil productivity, soil compaction, erosion and sedimentation, soil movement/ soil erosion, decrease in biodiversity of flora and fauna as well as changes in microclimate. Reclamation is the end of mining activities are expected to return the land to its original state. The ultimate objective of reclamation is to improve the Quarry to the condition safe, stable and not easily eroded so that it can be recovered. To see how far the influence of the reclamation of soil properties and its development, it is necessary to observe and study in detail the characterization of soil development on reclaimed land, whether it is possible that significant changes to the development of soil formation on land reclamation to the aspect physical, chemical and biological soil properties. The results indicate that the reclamation and increased of age affects the development of land reclamation seen from morphological, physical, chemical, and biological soil properties. Increased age of reclaimed coal mine land causes changes in the morphological soil property, especially on the top layer. The most affected changes of morphological soil properties by increasing age is the color of the land reclamation and the boundaries between layers, especially on the top soil layer due to the effect of adding organic matter. Increased age in the reclaimed land causes changes of soil physical properties, ie increased permeability and soil aggregate stability, but not affect bulk density. Increased age affects the chemical properties of soil reclamation, it is seen by an increase in C-organic, N-total, exchangables Ca and Mg content on topsoil. Changes of the biological soil properties occur until reclaimed coal mine land was 5 years old which in 5th years has the highest of individuals density, diversity indices and biomass.
Keyword: 

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