Judul: Analisis Sikap Konsumen dan Sensitivitas Harga Terhadap Jeruk Nama NIM. Medan dan Jeruk Mandarin di Y ogya Bogor Junction
Abstrak: Orange is one of fruits that have a lot of varieties in Indonesia. Free trade system make the Government cannot do much to tackle increase import oranges. The inclusion of orange mandarin to Indonesia made the consumers have a choice between consuming medan orange or mandarin orange. The methods used in this research is a descriptive analysis, multiatribut fishbein, and price sensitivity. The majority consumers of orange are woman, married, bachelor, age ≥ 36 years, worked as housewife and have income Rp 2 600 000 – Rp 5 000 000. Based on fishbein analysis, respondent prefer attribute on an mandarin orange. Range price of medan oranges is Rp 36 000 – Rp 45 000. Range price of mandarin orange is Rp 33 000 – Rp 47 500
Keyword: Bogor Agricultural University (IPB), Price sensitivity, Multiatribute Fishbein, ConsumerAttitudes

Judul: Faktor-Faktor yang Memengaruhi Konsumen Dalam Keputusan Pembelian Jeruk Mandarin
Abstrak: Jeruk lokal tidak kalah kualitasnya dengan jeruk impor, namun Indonesia masih mengimpor jeruk. Tujuan dari penelitian ini, yaitu (1) karakteristik konsumen jeruk mandarin, (2) proses pengambilan keputusan pembelian, dan (3) faktor yang memengaruhi keputusan konsumen dalam pembelian. Data yang digunakan adalah data primer dan sekunder dengan teknik volunteer sampling. Pengolahan data dilakukan secara kuantitatif dengan analisis deskriptif dan analisis faktor. Mayoritas responden merupakan laki-laki, berusia lebih dari 45 tahun. Pendidikan terakhir S1, pekerjaan pegawai swasta. Tujuan konsumen dalam membeli jeruk mandarin, yaitu sebagai makanan pencuci mulut. Tidak mencari informasi terlebih dahulu sebelum membeli. Masih akan membeli jeruk selain mandarin ketika sedang tidak tersedia. Tidak mau membeli jeruk mandarin jika harganya naik. Merasa puas terhadap warna dan rasa, serta harga yang ditawarkan sesuai dengan kualitas yang didapatkan. Keputusan konsumen dalam membeli jeruk mandarin dipengaruhi oleh delapan faktor utama, yaitu : 1) pengaruh lingkungan, 2) gengsi, 3) pengaruh dari keluarga, 4) preferensi pembelian di pasar tradisional, 5) preferensi pembelian di supermarket, 6) kebiasaan, 7) karakteristik jeruk mandarin, dan 8) pengaruh informasi., Local oranges are not inferior in quality to imported oranges, but Indonesia still imports oranges. The aims of this study are (1) the characteristics of mandarin orange consumers, (2) the purchasing decision making process, and (3) the factors that influence consumer purchasing decisions. The data used are primary and secondary data with voluntary sampling techniques. Data processing was carried out quantitatively with descriptive analysis and factor analysis. The majority of respondents are male, aged >45 years. Bachelor's degree, private employee job. Consumers buy mandarin oranges to consume it as a dessert. Customers not looking for further information. Will still buy another oranges when mandarin is not available. Won’t buy mandarin oranges if the price increasing. Satisfied with the color and taste, also the price offered according to the quality obtained. Consumer decisions in buying mandarin oranges are influenced by eight main factors, namely: environmental influences, prestige, family influences, purchasing preferences in traditional markets, purchasing preferences in supermarkets, habits, characteristics of mandarin oranges, and the influence of information.
Keyword: buying decision, consumer behaviour, mandarin orange

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.
Keyword: