Judul: Analysis of the Influence of the ASEAN Free Trade  Area (AFTA) on the Efficiency of Indonesia's Exports to ASEAN Countries  (period 1992-2020)
Abstrak: Salah satu bentuk integrasi ekonomi regional yang ada dalam ASEAN yaitu ASEAN Free Trade Agreement (AFTA). AFTA diharapkan dapat meningkatkan daya saing ekonomi kawasan regional ASEAN. Penelitian ini memiliki tujuan mengetahui apa faktor yang memengaruhi nilai ekspor Indonesia ke ASEAN dan mengestimasi derajat nilai efisiensi ekspor Indonesia ke negara ASEAN. Metode penelitian yang digunakan adalah Stochastic Frontier Gravity Model. Periode dalam penelitian ini adalah tahun 1992-2020 dan sampel diambil dari sembilan negara mitra ASEAN. Nilai efisiensi ekspor Indonesia ke 9 negara anggota ASEAN semenjak disetujuinya perjanjian AFTA ataupun semenjak AFTA resmi diberlakukan tidak berpengaruh signifikan terhadap efisiensi ekspor Indonesia ke 9 negara ASEAN. Faktor-faktor yang berhubungan positif terhadap nilai ekspor Indonesia ke ASEAN adalah trade openness, GDP riil Indonesia, GDP riil negara mitra dagang, populasi, nilai tukar riil, dan AFTA. Sementara nilai jarak ekonomi, dan landlocked berhubungan negatif terhadap ekspor Indonesia., One form of regional economic integration in ASEAN is the ASEAN Free Trade Agreement (AFTA). AFTA is expected to increase the economic competitiveness of the ASEAN region. This study aims to determine what factors influence the value of Indonesia's exports to ASEAN and to estimate the degree of efficiency in Indonesia's exports to ASEAN countries. The research method used is the Stochastic Frontier Gravity Model. The period in this study is the years 1992- 2020 and the samples were taken from nine ASEAN partner countries. The value of Indonesia's export efficiency to 9 ASEAN member countries since the approval of the AFTA agreement or since AFTA was officially enforced does not significantly affect the efficiency of Indonesia's exports to 9 ASEAN countries. Factors that are positively related to the value of Indonesia's exports to ASEAN are trade openness, Indonesia's real GDP, real GDP of trading partner countries, population, real exchange rate, and AFTA. Meanwhile, the value of economic distance and landlocked has a negative relationship with Indonesia's exports.
Keyword: ASEAN, exports efficiency, panel data, stochastic frontier gravity  model

Judul: Analysis of Indonesian Export Efficiency in the ASEAN Region,  Before and After the ASEAN Economic Community
Abstrak: Perdagangan internasional memiliki peran penting dalam pertumbuhan ekonomi di wilayah Association of South East Ation Nation (ASEAN). Integrasi perdagangan melalui kesepakatan ASEAN Economic Community memiliki keuntungan dapat menjangkau akses pasar yang lebih luas, mencapai tingkat efisiensi dan daya saing ekonomi yang lebih tinggi, serta penyerapan tenaga kerja yang lebih besar. Penelitian ini bertujuan untuk menganalisis faktor-faktor yang memengaruhi efisiensi ekspor barang Indonesia ke 9 negara mitra dagang di kawasan ASEAN sebelum dan sesudah ASEAN Economic Community (AEC). Metode yang digunakan dalam penelitian ini adalah stochastic frontier gravity model. Hasil analisis menunjukkan bahwa variabel PDB riil negara mitra dagang, PDB riil Indonesia, populasi, dan trade openness berpengaruh positif dan signifikan terhadap efisiensi ekspor. Sedangkan variabel jarak ekonomi memiliki pengaruh negatif dan signifikan terhadap efisiensi ekspor. Variabel riil exchange rate, landlocked, dan dummy AEC berpengaruh negatif dan tidak signifikan terhadap efisiensi ekspor Indonesia. Nilai efisiensi ekspor Indonesia selama periode penelitian selalu mengalami penurunan. Negara mitra dagang yang memiliki nilai efisiensi diatas rata-rata efisiensi ASEAN adalah Filipina, Kamboja, Brunei, dan Myanmar. Sedangkan negara Laos, Malaysia, Singapura, Thailand, dan Vietnam memiliki nilai efisiensi dibawah rata-rata ASEAN., International trade has an important role in economic growth of the Association of South East Nations (ASEAN). Trade integration through the ASEAN Economic Community (AEC) agreement has the advantage of being able to reach wider market access, achieve higher levels of efficiency and economic competitiveness, as well as greater employment. This study aims to analyze the factors that affect the efficiency of Indonesian goods exports to 9 trading partner countries in the ASEAN region before and after the ASEAN Economic 3 Community (AEC). The method used in this research is the stochastic frontier gravity model. The results of the analysis show that the variables of real GDP of trading partner countries, Indonesia's real GDP, population, and trade openness have a positive and significant effect on export efficiency. Meanwhile, the economic distance variable has a negative and significant effect on export efficiency. The real exchange rate, landlocked, and dummy AEC variables have a negative and insignificant effect on the efficiency of Indonesia's exports. The value of Indonesia's export efficiency during the study period has always decreased. Trading partner countries that have efficiency values above the ASEAN average efficiency are the Philippines, Cambodia, Brunei, and Myanmar. Meanwhile, Laos, Malaysia, Singapore, Thailand and Vietnam have efficiency values below the ASEAN average.
Keyword: AEC, ASEAN, Efficiency, Export of goods, Stochastic frontier gravity model

Judul: Hydrothermal Synthesis of Biphasic Calcium Posphate
Abstrak: Biphasio calsium phosphate (BCP), which was a mixture of hydroxypatite (HA) and tricalcium phosphate (TCP), was synthesized by hydrothermal method followed by sintering process. Hydroxyapatite was produced by using natural calcium source CaO from hen's eggshell and (NH4)2HPO4 as phosphate souce, other hydroxyapatite sample was produce by using synthetic calcium source Ca(OH) and H3PO4 as phosphate source.
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