Judul: Identifikasi karakteristik kegiatan bertani wilayah perkotaan : suatu studi urban agriculture di DKI Jakarta
Abstrak: Peningkatan populasi yang pesat berdampak pada penurunan ruang terbuka hijau (RTH) secara kuantitatif maupun kualitatif, akibat dari perubahan peruntukan lahan untuk pemenuhan kebutuhan penduduk perkotaan. Berbagai upaya revitalisasi perlu dilakukan agar keseimbangan ekosistem perkotaan dapat dipertahankan. Salah satu bentuk RTH yang dapat dikembangkan adalah dengan konsep "urban agriculture", yaitu pengisian RTH dengan tanaman budidaya. Tujuan dari penelitian ini adalah: 1) mengidentifikasi urban agriculture sebagai salah satu mega-city di Asia Tenggara, dengan menggunakan teknik sistem informasi geografi (SIG) dan penginderaan jauh (RS), dan 2) menganalisis faktor pengaruh pada persepsi masyarakat terhadap lanskap urban ariculture dengan metode scenic beauty estimation (SBE).
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Judul: Model kebijakan pengembangan pertanian perkotaan berkelanjutan (studi kasus: Wilayah DKI Jakarta)
Abstrak: Revitalization of agriculture is basically putting back the importance of agriculture in proportion and urban contexts. Considering the condition of agriculture in urban areas, especially areas of Jakarta and linkages with various environmental problems. It is expected that development of agriculture would not be sustainable. So it needs design action and formulation of comprehensive policy for sustainable development of urban agriculture. The study was aimed to analyze the sustainability of urban agriculture, to analyze the critical factors affecting the sustainability and policy of development urban agriculture. Analysis techniques used were MDS (multi-dimensional scaling) technique Rap-Ur-Agri (Rapid Appraisal for Urban Agriculture), an important factor with factor analysis level (leverage factor) and determination of sustainable agricultural development policy scenarios with a prospective analysis. Sustainability status of agricultural development on the condition of existing urban areas show an index value of 48.70% or less sustainable. Key factors for sustainability of urban agriculture are 4 (four) key factors, and attributes of stakeholders' needs are 4 (four) key factors. The light factors have been merged, so that it acquired six key factors that affect the development of urban agriculture systems. Scenarios of agricultural development policy of sustainable urban areas of Jakarta conducted with an integrative approach by improving the performance of atribute and six key factors: (1) yard size, (2) the development of commodity and environmentaly sound technology, (3) extension and agricultural institutions, (4) availability of urban land space, (5) cooperation among stakeholders, and (6) provision of agricultural incentives. MDS simulation results show that the pesimistic scenario with low improvement result sustainability index value 49.06%, moderate improvement scenario result sustainability index value 63.65% and optimistic scenario with the maximum improvement condition result sustainability index value at 76.85%. Development of policy direction consist of expansion of urban agriculture land and farm space, yards and fields/orchards, the development of environmentally friendly commodities and technology, social and institutional development of agriculture in the implementation strategy outlined.
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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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