Judul: Penentuan Titik Kritis Pascapanen Pepaya Carica papaya L. (Studi Kasus di Sentra Produksi Pepaya di Kabupaten Sukabumi, Banyumas, Kebumen, dan Boyolali)
Abstrak: Papaya (Carica papaya L.) is one a tropical fruit which is popular in Indonesia. Papaya is perishable fruits and has short postharvest life. Due to lack postharvest handling and its facility, losses in postharvest handling of papaya is still high. The range of total losses in postharvest handling for papaya is 25-40 percent. This total losess is identified from harvesting activity to the market. There are some actors in postharvest handling contribute in total losess. The objective of this study was to identify supply chain of papaya, to assess losess of papaya in supply chain, and to determine the critical point of postharvest losses of papaya. This study was carried out in the production center of papaya in Sukabumi (West Java), Banyumas, Kebumen and Boyolali (Central Java). The study was conducted by in dept-interview to all actors in supply chain of papaya, field observation to identify the supply chain and post-harvest losses and measurement of losess at each actors activities. The results showed that supply chain of papaya consists of farmers, collectors, suppliers, wholesalers, and retailers. The critical points of losess in postharvest handling of papaya in Kebumen and Boyolali was observed at the level of retailer. The different result was obtained in Sukabumi and Banyumas. In Sukabumi, the critical point in postharvest losess was found at suppliers level, in Banyumas was observed at wholesaler level.
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Judul: Pengujian Sifat Benih Pepaya (Carica Papaya L.) Dengan Perlakuan Penyimpanan Suhu Rendah
Abstrak: Papaya (Carica papaya. L) is a multi-purpose plant for almost all parts of this plant can be utilized. In this study using seeds that will detect the nature of papaya seeds. The research was conducted at the Laboratory of Seed in PKHT and Greenhouse Lewikopo, IPB, Bogor. The research was conducted in November 2011 until March 2012. In this study using a 3 kind papaya from PKHT that can represent all sizes of types of papaya. Sukma papaya varieties represent a large size, representing Callina papaya medium, and Carisya representing the size of a small papaya. This study uses two treatment factors, namely the period of store (0, 1, 2, and 3 months) and store temperature (room temperature (25-28 oC) and low temperature (-20 oC)). Before these edsare stored, carried the seeds drying in advance using a solution of MgCl to create different water levels. Observations carried out every month until the end of 3 month seriodesave on viability of papaya seeds. Results showed that the papaya Varieties Sukma have characteristic intermediate, while papaya Varieties Carisya and Calina included in characteristic orthodox.
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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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