Judul: Competitiveness Analysis and Affecting Factors of Indonesian Coffee Exports in the ASEAN Market
Abstrak: Kopi merupakan komoditas ekspor utama dan merupakan salah satu penghasil devisa terbesar dari sektor pertanian Indonesia. Penelitian ini bertujuan untuk menganalisis daya saing dan faktor yang memengaruhi ekspor serta memproyeksikan ekspor kopi Indonesia di kawasan ASEAN tahun 2021-2025. Metode yang digunakan yaitu Revealed Comparative Advantage (RCA), Export Product Dynamic (EPD), Rasio Akselerasi (RA), ARIMA, dan Gravity Model. Hasil RCA menunjukkan kopi Indonesia memiliki keunggulan komparatif di Kawasan ASEAN. Analisis EPD menunjukkan bahwa Indonesia hanya berdaya saing di negara Thailand dan Filipina, sedangkan Malaysia dan Singapura berada pada posisi retreat dan falling star. Berdasarkan analisis RA, Indonesia dapat merebut pasar ekspor kopi di kawasan ASEAN. Perkembangan ekspor kopi dipengaruhi oleh beberapa faktor. Hasil uji T menunjukkan bahwa GDP riil Indonesia, GDP riil pengimpor, jarak ekonomi, harga ekspor Indonesia memiliki pengaruh secara signifikan terhadap ekspor kopi Indonesia di kawasan ASEAN. Variabel populasi pengimpor memiliki pengaruh yang positif namun tidak signifikan terhadap volume ekspor kopi Indonesia di kawasan ASEAN. Hasil proyeksi juga menunjukkan bahwa pada tahun 2021- 2025, ekspor kopi Indonesia akan memiliki pertumbuhan yang positif, Coffee is one of the leading export commodities and the largest foreign exchange contributor from the Indonesian agricultural sector. This study aims to analyze competitiveness and the affecting factors of coffee exports and forecast the Indonesia's coffee exports in the ASEAN market in 2021-2025. The methods used are Revealed Comparative Advantage (RCA), Export Product Dynamic (EPD), Acceleration Ratio (AR), ARIMA, and Gravity Model. The RCA results show that Indonesian coffee has a comparative advantage in the ASEAN Region. EPD analysis shows that Indonesia is only competitive in Thailand and the Philippines, while Malaysia and Singapore are in a retreat and falling star position. Based on RA's analysis, Indonesia can seize the coffee export market in the ASEAN region. The development of coffee exports is influenced by several factors. The result of T-test shows that the Indonesia's real GDP, importers' real GDP, economic distance, Indonesia's export prices have a significant effect on the volume of Indonesia’s coffee export in the ASEAN region. The importing population has no significant effect to the volume of Indonesia’s coffee export in the ASEAN region. The forecasting results also show that in 2021-2025, Indonesia's coffee exports will have positive growth in the ASEAN Region.
Keyword: AR, ARIMA, EPD, Gravity Model, and RCA

Judul: Analisis Daya Saing dan Faktor-Faktor yang Memengaruhi Ekspor Olahan Kopi Indonesia di Pasar ASEAN
Abstrak: Sebagai salah satu negara penghasil kopi terbesar, Indonesia masih lebih banyak mengekspor kopi dalam bentuk biji mentah dibandingkan produk olahannya. Hal ini mendorong Kementrian Industrian untuk mengembangkan nilai tambah serta daya saing dengan pengembangan sektor industri kopi. Penelitian ini bertujuan untuk: (1) menganalisis daya saing komparatif olahan kopi Indonesia di pasar ASEAN; (2) menganalisis daya saing kompetitif olahan kopi Indonesia di pasar ASEAN; (3) menganalisis faktor-faktor yang memengaruhi volume ekspor olahan kopi Indonesia di pasar ASEAN. Metode analisis yang digunakan adalah Revealed Symmetric Comparative Advantage (RSCA), Export Product Dynamic (EPD), dan regresi data panel. Hasil analisis RSCA menunjukkan olahan kopi Indonesia memiliki keunggulan komparatif di tiga pasar ASEAN, yaitu Filipina, Malaysia, dan Singapura untuk HS 210111, dan Filipina, Malaysia, Thailand untuk HS 210112. Hasil analisis EPD menunjukkan bahwa Indonesia memiliki posisi pasar Rising Star di Filipina untuk olahan kopi dengan kode HS 210112. Faktor-faktor yang memengaruhi volume ekspor ekstrak, esens, konsentrat kopi Indonesia (HS 210111) secara signifikan adalah harga ekspor. Faktor-faktor yang memengaruhi volume ekspor olahan dari ekstrak, esens, konsentrat kopi Indonesia (HS 210112) secara signifikan adalah harga ekspor dan Logistic Performance Index (LPI) negara tujuan., As one of the largest coffee producing countries, Indonesia still exports more coffee in the form of raw beans than processed products. This encourages the Ministry of Industry to develop added value and competitiveness by developing the coffee industry sector. This research aims to: (1) analyze the comparative competitiveness of processed Indonesian coffee in ASEAN market; (2) analyze the competitive competitiveness of processed Indonesian coffee in ASEAN market; (3) analyze the factors that influence the volume of exports of processed Indonesian coffee in ASEAN market. The analysis methods used are Revealed Symmetric Comparative Advantage (RSCA), Export Product Dynamic (EPD), and panel data regression. The results of the RSCA analysis show that Indonesian processed coffee has a comparative advantage in three ASEAN countries, namely the Philippines, Malaysia and Singapore for HS 210111, and the Philippines, Malaysia, Thailand for HS 210112. The results of the EPD analysis show that Indonesia has a Rising Star market position in the Philippines for processed coffee with the HS code 210112. Factors that significantly influence the export volume of Indonesian coffee extracts, essences and concentrates (HS 210111) are export prices. Factors that significantly influence the volume of processed exports of Indonesian coffee extracts, essences and concentrates (HS 210112) are the export price and the Logistic Performance Index (LPI) of the destination country.
Keyword: arabica, coffee extract, instant coffee, international trade, robusta

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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