Judul: Pengaruh Kondisi Lahan Pertanian terhadap Kelimpahan Serangga Penyerbuk: Implikasi terhadap Produksi Mentimun
Abstrak: Insect pollinators play an important role in pollination on various plants, including cucumber. This research aims to study the influence of natural habitat toward the abundance of insect pollinator and its effect on cucumber production. This research was conducted at six locations with various distances to natural habitat. Three locations were categorized as locations near natural habitat, i.e. less than 200 m. The other three locations were categorized as locations far from natural habitats, i.e. 1000 m. The observations of insect pollinator abundance were conducted by counting the number of insect pollinator that perched on 100 units flower in four different spots. The observations were conducted at four different times. Several variables were observed, i.e. the weight of cucumber, amount of seeds, dried weight of seeds, length and width of cucumber, on four different subplots sized 1 m x 1 m. The results showed that the presence of natural and seminatural habitats surrounding agricultural land, influence the abundance of insect pollinators. Whereas time of the highest numbers of insects pollinating the flower were at 9 am, 11 am and 3 pm. There is no correlation between the numbers of individuals with cucumber production.
Keyword: natural habitat., insect pollinator, cucumber production, abundance

Judul: Pengaruh Pengeringan, Media Pengujian, Waktu Panen dan Kondisi Ruang Simpan terhadap Viabilitas Serbuk Sari Mentimun (Cucumis sativus L.).
Abstrak: The objectives of this research were to study the decline of cucurbits pollen viability during desiccation, to determine the suitable germination medium for cucumber pollen, to determine the best time for pollen harvesting and to study thestorability of Cucumis sativus pollen. The study was carried out during March- August 2011 at Production Farm and Pollen Laboratory, PT East West Seed Indonesia in Jember, East Java. Viability of pollen harvested on the day of anthesis decreased after anther drying in air-conditioned room for 24 hours and decreased further after pollen drying in MgCl2 for 24 hours. Viability of pollen harvested one day before anthesis increased after anther drying in airconditioned room for 24 hours, then decreased after drying in MgCl2 for 24 hours. PGM 1, PGM 2 (modified from the original), Brewbacker and Kwack (BK), E1, and E2 were pollen germination medium used in this experiment. The male parental stock of KE010, KE014, KE018, and KE019 were used as the pollen source. The result showed that KE014 pollen germinated in PGM 1 had higher germination than BK, on the first trial. In the second trial, PGM 1 also showed higher germination than E2. Pollen of KE010, KE018, and KE019 germinated in PGM 2 produced higher germination than PGM 1 in in the third trial. The pollen harvesting was done at 07.00, 09.00, 11.00, 13.00, 15.00, 17.00 one day before anthesis and on the day of anthesis (A-1 and A) on KE010, KE018, KE019. The result showed that the best time for pollen harvesting for the three varieties was during 07.00-11.00 on the day of anthesis with viability at about 35%. The storage conditions under investigation for cucumber pollen were freezer, deep freezer, and ultra freezer. The most suitable storage condition for cucumber pollen (KE010, KE018, KE019) was ultra freezer, in which viability of cucumber pollen more than 1% would keep for 42 HSS (6 weeks), 90 HSS (12 weeks), 9 HSS (1.5 weeks) without any significant decline on germination.
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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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