Judul: Perbandingan Analisis Kelayakan Usaha Jambu Kristal (Psidium guajava L.) Petani Mandiri dengan Petani Binaan ICDF Kabupaten Bogor
Abstrak: Kristal guava presents as popular primadona fruits. Nowdays, there is a gap between demand and production. This gap could be an opportunity to open kristal guava business. The purpose of this research is to compare feasibility analysis of kristal guava between independent farmer (Mr.Agus) and mentored farmer by ICDF (Mr.Badri). The research was conducted at Tangkil Village and Cikarawang Village. Is that ICDF bring a positive effect to the farmer. Data analysis method which is used on this research is qualitative analysis method to analyze feasibility based on non-financial aspect such as market aspect, technical aspect, management and legal aspect, and also sosial, economic, culture and environmental aspect. Quantitative analysis based on investment criteria and sensitivity analysis using switching value to analyze feasibility based on financial aspect. The result of this feasibility analysis shows that kristal guava cultivation is feasible to run. Based on the sensitivity analysis using a switching value.
Keyword: kristal guava, comparison feasibility

Judul: Analysis of Income and Marketing of Crystal Guava Farming (Psidium Guajava) at Bojong Farm Sukabumi
Abstrak: Jambu biji merupakan salah satu komoditas pertanian sub hortikultura di Indonesia yang tingkat produksinya selalu meningkat setiap tahunnya, mulai dari tahun 2018 sampai dengan 2021. Jambu kristal merupakan varietas mutasi dari jambu biji yang dikembangkan oleh Institut Pertanian Bogor (IPB) dan menghasilkan buah yang lebih manis dan biji buah jambu biji yang lebih sedikit. Jambu kristal memiliki perawatan yang mudah dan harga jual yang tinggi sehingga menjadikan jambu kristal sendiri sebagai daya tarik untuk petani dalam melakukan usaha tani jambu kristal. Pemasaran jambu kristal yang efisien dan efektif menjadi hal yang penting untuk memenuhi permintaan pasar yang selalu meningkat, selain itu dengan pemasaran yang efisien secara tidak langsung akan meningkatkan pendapatan dari petani jambu kristal lebih besar. Kelompok tani (poktan) merupakan salah satu lembaga yang memiliki banyak fungsi yang bermanfaat bagi petani, salah satu fungsi-fungsi tersebut merupakan solusi bagi petani dalam mengatasi masalah produksi dan penjualan. Poktan Assosiasi Jambu Kristal Bojong Farm merupakan salah satu lembaga yang berada di Bojong Kembar, Cikembar, Sukabumi yang menjadi lembaga objek dari penelitian ini. Tujuan dari penelitian ini adalah menganalisis dan membandingkan pendapatan usaha tani petani anggota dan non-anggota poktan. Metode analisis untuk mengetahui efisiensi pendapatan usaha tani jambu kristal menggunakan R/C ratio dan untuk pemasaran menggunakan marjin pemasaran, farmer’s share dan rasio keuntungan terhadap biaya pemasaran. Pendapatan R/C ratio atas biaya tunai dan biaya total usaha tani jambu kristal anggota poktan lebih baik dibandingkan non-anggota. Hal ini dikarenakan harga jual di tingkat petani anggota poktan lebih tinggi dibandingkan dengan non-anggota poktan. Hasil dari analisis efisiensi pemasaran menunjukkan bahwa pemasaran jambu biji kristal non-anggota poktan merupakan saluran pemasaran yang lebih efisien dibandingkan pemasaran anggota poktan. Hal ini dikarenakan saluran pemasaran petani non-anggota poktan lebih pendek sehingga mengakibatkan marjin pemasaran yang rendah., Analysis of Income and Marketing of Crystal Guava Farming (Psidium Guajava) at Bojong Farm Sukabumi. Supervised by NINDYANTORO. Guava is one of the sub-horticultural agricultural commodities in Indonesia whose production level always increases every year, starting from 2018 to 2021. Crystal guava is a mutated variety of guava developed by Bogor Agricultural University (IPB) and produces sweeter fruit and fewer guava seeds. Crystal guava has easy maintenance and a high selling price, making crystal guava itself an attraction for farmers in conducting crystal guava farming. Efficient and effective marketing of crystal guava is important to meet the ever-increasing market demand, and efficient marketing will indirectly increase the income of crystal guava farmers. Farmer groups (Poktan) are one of the institutions that have many functions that are beneficial to farmers, one of these functions is a solution for farmers in overcoming production and sales problems. Bojong Farm Crystal Guava Association is one of the institutions located in Bojong Kembar, Cikembar, Sukabumi which is the object institution of this research. The purpose of this research is to analyze and compare farm income of farmer members and non-members of Poktan. The analysis method to know the efficiency of crystal guava farming income using R/C ratifmeo and for marketing using marketing margin, farmer's share and profit to marketing cost ratio. The R/C ratio on cash costs and total costs
Keyword: Efisiensi Pemasaran, farmer’s share, Marjin Pemasaran, Pendapatan usahatani, R/C ratio

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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