Judul: Daya Saing dan Determinan Ekspor Udang Beku Indonesia di Negara Tujuan Ekspor
Abstrak: Frozen shrimp is one of Indonesian export commodities that has the biggest shares on total fisheries export. Indonesia is the fourth biggest exporters of frozen shrimp in the world. However, it didn’t mean that competitiveness is high too. Hence, the purposes of this research are to analyze competitiveness and market position of frozen shrimp and to analyze the determinant of export of frozen shrimp in the world, especially on 15 countries from 2004-2013 using gravity model analyzed by static data panel. RCA (Revealed Comparative Advantage) analysis shows that frozen shrimp Indonesia has high comparative advantage on all destination countries except Spain. EPD (Export Dynamic Product) analysis shows that market position is rising star only in United States. Meanwhile, market position is in lost opportunity in nine destination countries and the rest is in retreat. Based on gravity model, it is shown that the increasing on GDP real per capita of destination country, frozen shrimp price of rival country, and economics distance have positive effect on frozen shrimp export. Meanwhile, the increasing on GDP real per capita of Indonesia, frozen shrimp price of Indonesia, and real exchange rate have negative effects on frozen shrimp export.
Keyword: Bogor Agricultural University, volume of export., RCA, market position, gravity model, EPD

Judul: Competitiveness and Factors Affecting Indonesian Frozen Shrimp Exports in Main Destination Countries and Potential Countries
Abstrak: Komoditas udang berkontribusi besar terhadap total nilai ekspor subsektor perikanan di Indonesia. Tahun 2020 Indonesia menduduki peringkat ke-4 sebagai negara eksportir udang beku terbesar di dunia namun nilai ekspor komoditas tersebut masih berfluktuasi setiap tahunnya. Share volume ekspor udang beku Indonesia di pasar dunia masih rendah dibandingkan dengan negara pesaingnya yaitu Ekuador, India, dan Vietnam. Penelitian ini bertujuan menganalisis daya saing dan faktor-faktor yang memengaruhi ekspor udang beku Indonesia di enam negara tujuan utama. Hasil penelitian dengan menggunakan RCA menunjukkan bahwa ekspor udang beku Indonesia memiliki keunggulan komparatif di enam negara tujuan utama. Analisis EPD menjelaskan bahwa udang beku Indonesia hanya memiliki keunggulan kompetitif atau Rising Star di Kanada, sementara di pasar Amerika Serikat dan Belanda berada pada kondisi Falling Star, di pasar China pada kondisi Lost Opportunity, dan hasil yang lebih buruk di pasar Jepang dan Perancis berada pada kondisi Retreat. Faktor-faktor yang memengaruhi volume ekspor udang beku Indonesia secara signifikan dengan taraf nyata lima persen yaitu nilai harga udang beku Indonesia ke negara tujuan berpengaruh secara negatif dan jarak ekonomi yang berpengaruh secara negatif. Dua variabel lainnya tidak berpengaruh secara signifikan yaitu variabel GDP negara tujuan dan nilai tukar negara tujuan., Shrimp commodity contributes greatly to the total export value of the fisheries sub-sector in Indonesia. In 2020, Indonesia was ranked 4th as the largest frozen shrimp exporter in the world, but the export value of this commodity still fluctuates every year. Indonesia's frozen shrimp export volume in the world market is still low compared to its competitors, namely Ekuador, India, and Vietnam. This study aims to analyze the competitiveness and factors that influence Indonesia's frozen shrimp exports in six main destination countries. The results of the research using RCA show that Indonesia's frozen shrimp exports have a comparative advantage in the six main destination countries. EPD analysis explains that Indonesian frozen shrimp only has a competitive advantage or Rising Star in Kanada, while in the United States and the Netherlands markets are in Falling Star conditions, in the Chinese market in Lost Opportunity conditions, and worse results in the Japanese and French markets in retreat condition. The factors that significantly affect the volume of Indonesia's frozen shrimp exports with a significant level of five percent, namely the price value of Indonesian frozen shrimp to the destination country has a negative effect and economic distance has a negative effect. Two other variables have no significant effect, namely the destination country variable and the country's exchange rate.
Keyword: Distance, Export Product Dynamic, Gravity Model, Price, Revealed Comparative Advantage

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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