Judul: Analisis Dampak Non-Tariff Measures dan Faktor-Faktor yang Memengaruhi Ekspor Buah-Buahan Indonesia ke Negara Tujuan
Abstrak: Buah-buahan merupakan salah satu komoditas yang menjadi unggulan dalam ekspor sektor hortikultura Indonesia. Adanya hambatan non tarif (non tariff measures/NTMs) dalam perdagangan internasional produk pertanian, khususnya pada buah-buahan Indonesia dapat membuat volume ekspor buah-buahan Indonesia ke negara tujuan mengalami penurunan. Lebih lanjut, hambatan non tarif yang sering diberlakukan adalah kebijakan Sanitary and Phytosanitary (SPS) dan Technical Barries to Trade (TBT). Pada penelitian ini dianalisis dampak NTMs serta faktor-faktor yang memengaruhi ekspor buah-buahan Indonesia pada periode 2010 hingga 2019 ke negara tujuan. Metode yang digunakan pada penelitan ini terdiri dari analisis deskriptif dengan menggunakan pendekatan inventory dan analisis data panel dengan menggunakan model gravity. Hasil analisis inventory menunjukkan bahwa komoditas buah-buahan Indonesia paling banyak dikenakan kebijakan SPS dengan jenis testing requirement. Selanjutnya, hasil estimasi model gravity menunjukkan GDP riil negara pengimpor, GDP riil Indonesia, populasi negara pengimpor, populasi Indonesia, jarak ekonomi, nilai tukar riil, dan coverage ratio SPS berpengaruh signifikan terhadap volume ekspor buah-buahan Indonesia., Fruits are one of the leading commodities in Indonesia's horticultural sector exports. The existence of non-tariff barriers (non-tariff measures/NTMs) in the international trade of agricultural products, especially Indonesian fruit has reduced the volume of Indonesian fruit exports to the destination countries. Furthermore, non-tariff barriers that are often applied are the Sanitary and Phytosanitary (SPS) and Technical Barriers to Trade (TBT) policies. This study analyzes the impact of NTMs and the factors that affect the Indonesian fruits exports in the period 2010 to 2019 to destination countries. The method used in this research consists of descriptive analysis using an inventory approach and panel data analysis using a gravity model. The results of the inventory analysis show that the most Indonesian fruit commodities are subject to the SPS policy with the type of testing requirement. Furthermore, the estimation results of the gravity model show that the real GDP of the importing country, the real GDP of Indonesia, the population of the importing country, the population of Indonesia, the economic distance, the real exchange rate, and the SPS coverage ratio have a significant effect on the volume of Indonesian fruit exports.
Keyword: export, fruits, gravity model, inventory approach, NTMs

Judul: Analisis Dampak Non Tariff Measures (NTMs) terhadap Ekspor Manggis Indonesia ke Negara Tujuan Utama
Abstrak: Manggis merupakan salah satu komoditas ekspor unggulan subsektor tanaman hortikultura yang berpengaruh terhadap nilai PDB Indonesia dimana ekspor komoditas manggis berkontribusi sebanyak 81 juta USD pada tahun 2021. Namun, ekspor manggis Indonesia masih terhalang dengan hambatan non tarif atau Non-Tariff Measures (NTMs). Kebijakan yang paling banyak diterapkan pada komoditas manggis adalah Sanitary and Phytosanitary Measures dan Technical Barrier to Trade. Penelitian ini bertujuan untuk menganalisis pemberlakuan NTMs pada ekspor manggis Indonesia di negara tujuan utama, yaitu Cina, Hong Kong, Uni Emirat Arab, Malaysia, dan Singapura serta menganalisis pengaruh NTMs yang diterapkan oleh negara tujuan terhadap ekspor manggis Indonesia. Hasil inventory approach yang telah dilakukan adalah Uni Emirat Arab merupakan negara yang memberlakukan NTMs terbanyak, yaitu 81 kebijakan dengan nilai frequency index dan coverage ratio yang paling beragam. Berdasarkan hasil regresi data panel yang dilakukan kebijakan SPS tidak berpengaruh secara signifikan dan memiliki hubungan negatif terhadap volume ekspor manggis Indonesia sedangkan kebijakan TBT berpengaruh secara signifikan dan memiliki hubungan negatif terhadap volume ekspor manggis Indonesia., Mangosteen is one of the leading export commodities in the horticulture cub-sector which has an impact on Indonesia’s GDP value, where mangosteen commodity exports contribute as much as USD 81 million in 2021. However, Indonesia’s mangosteen exports are still hampered by Non-Tariff Measures (NTMs). The policies most widely applied to mangosteen commodities are Sanitary and Phytosanitary Measures and Technical Barriers to Trade. This study aims to analyze the application of NTMs to Indonesian mangosteen exports in the main destination countries and to analyze the effect of NTMs applied by destination countries on Indonesian mangosteen exports. The result of the inventory approach that has been carried out is that the United Arab Emirates is the country with the most NTMs, namely 81 policies with the most diverse frequency index and coverage ratio values. The results of the panel data regression carried out by the SPS policy have no significant effect and have a negative relationship to Indonesia's mangosteen export volume, while the TBT policy has a significant effect and has a negative relationship to Indonesia's mangosteen export volume.
Keyword: Inventory approach, SPS, TBT, Mangosteen

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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