Judul: Analisis Daya Saing Kakao Olahan Indonesia di Negara Tujuan Ekspor Utama
Abstrak: Indonesia merupakan salah satu negara produsen kakao terbesar di dunia sehingga memiliki potensi yang baik dalam meningkatkan ekspor kakao olahan. Penelitian ini bertujuan untuk (1) menganalisis keunggulan komparatif kakao olahan Indonesia di negara tujuan ekspor utama, (2) menganalisis keunggulan kompetitif kakao olahan Indonesia di negara tujuan ekspor utama, dan (3) menganalisis faktor-faktor yang mempengaruhi ekspor kakao olahan Indonesia di negara tujuan ekspor utama. Metode analisis yang digunakan adalah Revealed Comparative Advantage (RCA), Export Product Dynamic (EPD), Acceleration Ratio (AR), dan Gravity Model. Analisis RCA menunjukkan bahwa kakao olahan Indonesia berdaya saing kuat di negara tujuan ekspor utama. Analisis EPD menunjukkan bahwa posisi pasar ekspor kakao olahan Indonesia berada pada posisi Rising Star dan Lost Opportunity. Analisis AR menunjukkan bahwa Indonesia mampu merebut pasar kakao olahan di negara tujuan ekspor utama. Faktor-faktor yang mempengaruhi ekspor lemak kakao adalah GDP riil per kapita negara tujuan, GDP riil per kapita Indonesia, nilai tukar riil negara tujuan terhadap dollar AS, sedangkan untuk bubuk kakao adalah GDP riil per kapita negara tujuan, GDP riil per kapita Indonesia, nilai tukar riil negara tujuan terhadap dollar AS, dan jarak ekonomi., Indonesia is one of the biggest cocoa producers in the world so it has a great potential to increase processed cocoa export. This research aims to: (1) analyze the comparative advantage of Indonesian processed cocoa in the main export destination countries, (2) analyze the competitive advantage of Indonesian processed cocoa in the main export destination countries, and (3) analyze the factors that affect the export of Indonesian processed cocoa in the main export destination countries. The analytical methods are Revealed Comparative Advantage (RCA), Export Product Dynamic (EPD), Acceleration Ratio (AR), and Gravity Model. RCA analysis showed that Indonesian processed cocoa has strong competitiveness in the destination countries. EPD analysis showed that the market position of the Indonesian processed cocoa export is either Rising Star or Lost Opportunity. AR analysis showed that Indonesia has able to seize the export market for all processed cocoa in all destination countries. Variables that affect the export of cocoa butter are the real GDP per capita of the destination countries, the real GDP per capita of Indonesia, the real exchange rate, while for cocoa powder are the real GDP per capita of the destination countries, the real GDP per capita of Indonesia, the real exchange rate, and the economic distance.
Keyword: Acceleration Ratio (AR), export duty, Export Product Dynamic (EPD), Gravity Model, Revealed Comparative Advantage (RCA)

Judul: Daya Saing dan Faktor - Faktor Yang Memengaruhi Ekspor Kakao Olahan Indonesia di Negara Tujuan Utama
Abstrak: Kakao merupakan komoditas unggulan ekspor perkebunan Indonesia. Komoditas turunan kakao yaitu lemak kakao termasuk komoditi yang berkontribusi besar untuk perekonomian Indonesia. Tujuan penelitian ini untuk menganalisa daya saing dan faktor– faktor yang memengaruhi ekspor kakao olahan Indonesia dengan kode HS 1804 di negara tujuan utama. Penelitian ini menggunakan data sepuluh negara tujuan utama dengan periode 2013-2018. Regresi data panel, RCA dan EPD adalah metode analisis yang digunakan. Berdasarkan penelitan hasil Revealed Comparative Advantage (RCA) menunjukkan ekspor kakao olahan Indonesia berdaya saing kuat serta memiliki keunggulan komparatif di semua negara tujuan. Hasil analisis Export Product Dynamic (EPD) menggambarkan Amerika Serikat, Kanada, China, dan Estonia pada posisi Rising Star, posisi Falling Star yaitu Australia, Jepang, Belanda, India, dan Jerman. Posisi Retreat yaitu negara Malaysia. Model terbaik pada penelitian ini yaitu pendekatan Fixed Effect Model. Regresi data panel menggambarkan harga eskpor dan GDP riil negara tujuan berpengaruh signifikan terhadap nilai ekspor kakao olahan Indonesia. Sedangkan nilai tukar riil berpengaruh negatif terhadap nilai ekspor kakao olahan., Cocoa is Indonesia's leading plantation export commodity. Cocoa derivative commodity, namely cocoa butter, is one of the several strategic commodities that have a great opportunity for export. The aim of this research is to the analyze the competitiveness and the factors affecting Indonesia’s exports of processed cocoa with the HS code 1804 to the ten main destination countries. This study uses data from ten countries for the 2013- 2018 period. Panel data regression, RCA, and EPD are the analytical methods used. Based on the research, the results of the RCA show that Indonesia's processed cocoa exports are highly competitive and have a comparative advantage in all destination countries. The results of the EPD analysis describe that the United States, Canada, China, and Estonia in the Rising Star, Falling Star positions, Australia, Japan, the Netherlands, India and Germany. The position of the Retreat is Malaysia. The best model in this study is the Fixed Effect Model approach. Panel data regression shows that export prices and Real GDP of destination countries have a significant effect on the export value of Indonesian processed cocoa. Meanwhile, the real exchange rate have a negative effect on the export value of Indonesian processed cocoa.
Keyword: Cacao, EPD, Export, Panel Data, RCA

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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