Judul: Turmeric (Curcuma Domestica Val.) Plants Under Agroforestry Stands Jabon (Anthocephalus Cadamba Miq.)
Abstrak: Planting of jabon (A. cadamba) tree species have attracted many people in recent times due to its fast growing ability, cylindrical trunk with a good level of alignment, and the ability of natural pruning. Jabon tree branches arevalso high allowing light in from the side, to enhance natural regeneration. To optimize jabon forests, land can be developed through agroforestry systems. Agroforestry provides income daily, weekly, monthly and even yearly longer period for farmers. Therefore, it is necessary for the development of agroforestry jabon plant types that are resistant to shade. Turmeric (C. domestica) may be an option for agroforestry crop jabon as turmeric can be grown in shade conditions. In addition, turmeric has many benefits, thus, its use is not limited to the rhizome and the leaves can also be used as a spice in cooking to add flavor. Turmeric is also used as a refreshing drink, a natural preservative, medicinal materials (anti-Alzheimer's disease, anti-tumor, anti-diabetic), fodder for livestock and also for forensic purposes (fingerprint visualization). The results of the study treatments extract of leaves and twigs jabon shows extracts of leaves and twigs application Jabon not inhibit the growth of turmeric plants. The applications extraction of leaves and twigs of jabon showed no allelopathic effect, wherein the extract of leaves and twigs treatment of white Jabon did not inhibit the growth of turmeric plants, decrease the production of rhizomes and reduce the content of curcumin at the of age 6 BST. Agroforestry research conducted at the 3.9-year old jabon stands average shade level of 73.7% shade. The results showed that treatment J3 (Urea, SP-36, and KCl with each dose of 250 kg ha-1) was high in production from treatments J2 (Urea, SP-36, and KCl with each dose of 200 kg ha-1) and as well as treatment J1 (Urea, SP-36, and KCl with each dose of 150 kg ha-1) to the weight of the rhizome. Production of turmeric at the age of 6 months after planting (BST) ranged between 7.4 and 11.9 tons ha-1 and producing 9.9-16.4 tons ha-1 at the age of 8 BST. The content of curcumin at age 6 BST is 6% has met the standard MMI 5%.
Keyword: agroforestry, jabon, turmeric, curcumin, residues

Judul: Silvicultrual practices and growth of jabon tree (Anthocephalus cadamba Miq) in Community Forest, West Java, Indonesia
Abstrak: Jabon (Anthocephalus cadamba Miq.) is a native species in Indonesia. This fast growing tree is now preferred for the local community to plant because of its good adaptability and economic profitability. However, the information of this tree and silvicultural practices is still lacking. Therefore, there are three main objectives of this research: 1) to document the existing silvicultural practices of jabon implemented by local communities in West Java. 2) to investigate tree growth performance among different sites in West Java. 3) to examine the linkage of silvicultural practices and soil fertility for stand quality. This research covered following aspects; stand inventory, soil sampling and interview with local communities who planted jabon in the districts of Bogor, Sukabumi, Sumedang and Purwakarta. With 0.02 or 0.04 ha size sample plots, a stand inventory has been conducted and the diameter and height are measured. In addition, pest investigation also has been carried out at same sample plots. In addition, soil sampling and interview have done to collect site information and silvicultural practices in each site. After collecting various data from jabon plantation in West Java, those data are analyzed in forms of tabulation and regression graph. According to the results of the interview, most jabon plantations are owned by outsiders from Jakarta or other cities. There are three types of management: partnership, hiring employees and direct management. There are only a few practitioners have participated in silvicultural training. In spite of the absence of systematic silvicultural training, all practitioners have implemented basic silvicultural practices: land preparation and planting, fertilizing, maintenance and pest and disease control. Moreover, most of sites in same village have same or similar silvicultural practices because usually only one manager or farmer maintains all plantations. After an inventory of jabon plantations in West Java, there are totally 56 plots have been inventoried in 20 sites. The age of jabon tree ranges from 0.5-year to 3.5-year because jabon tree has been introduced in Java since 2008. The mean diameter ranges from 2.45 cm to 14.57 cm with maximum 29.3 cm and the mean height of 1.29 m to 12.62 m with maximum 18.68m in Situgede. As a result of regression modeling with dominant height, one Chapman model has been selected to calculate site index curve.: Hd 􀵌 10. 6982􁈺1 􀵆 exp􁈺􀵆0.8915t􁈻􁈻􀀀.􀀀􀀀􀀀􀀀 with 0.6513 R-square value. This curve helps to divide 20 sites into three categories: good, medium and poor. Based on analysis, there are two good sites, twelve medium and six poor sites. There are three DBH-age equations can be estimated based on site classifications. As a result of comparison between good and poor sites, it seems that site conditions and soil fertility have a more significant impact on growth of jabon than silvicultrual practices like fertilization and maintenance.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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