Judul: Hedging for Arabica Coffee’s Prices in Indonesia Using Options Strategies
Abstrak: Meningkatnya konsumsi kopi di Indonesia yang disertai dengan adanya pandemi Covid-19 dan fenomena embun beku di Brazil menyebabkan harga kopi Arabika meningkat pesat. Lindung nilai menggunakan strategi opsi dapat menjadi solusi untuk mengurangi risiko jika menghadapi kondisi bullish di masa depan. Penelitian ini menggunakan tiga strategi opsi, yaitu long call, short combo, dan vertical ratio call back spread. Berdasarkan hasil penghitungan, biaya vertical ratio call back spread merupakan yang terendah pada kondisi bearish dan short combo pada kondisi bullish. Pada kondisi neutral, biaya terendah dicapai ketika tidak dilakukan strategi opsi. Ketiga strategi opsi memiliki keuntungan maksimum tak terhingga jika terjadi peningkatan spot price, sedangkan kerugian maksimum terjadi pada kondisi dan nilai yang berbeda-beda. Vertical ratio call back spread lebih menguntungkan pada kondisi bearish, sedangkan short combo lebih menguntungkan pada kondisi bullish., The increasing consumption of coffee in Indonesia, which is accompanied by the Covid-19 pandemic and the frost phenomenon in Brazil, caused the price of Arabica coffee to increase rapidly. Hedging using an option strategy can be a solution to reduce risk if facing bullish conditions in the future. This study uses three option strategies, namely long call, short combo, and vertical ratio call back spread. Based on the calculation results, the cost of the vertical ratio call back spread is the lowest in bearish conditions and the short combo in bullish conditions. In neutral conditions, the lowest cost is achieved when the option strategy is not carried out. The three option strategies have an infinite maximum profit if the spot price increases, while the maximum loss occurs at different conditions and values. The vertical ratio call back spread is more profitable in bearish conditions, while the short combo is more profitable in bullish conditions.
Keyword: Arabica coffee, hedging, long call, short combo, vertical ratio call back spread

Judul: Hedging for Crude Palm Oil's Price Using Bull Call Spread Strategy and Short Combo Straregy
Abstrak: Ketidakstabilan demand dan supply yang terjadi akibat adanya pandemi Covid-19 menyebabkan harga crude palm oil di Indonesia meningkat pesat. Lindung nilai menggunakan strategi opsi dapat menjadi solusi untuk mengurangi risiko jika menghadapi kenaikan harga atau kondisi bullish di masa depan. Penelitian ini menggunakan dua strategi opsi, yaitu strategi bull call spread dan short combo. Berdasarkan hasil penghitungan, biaya short combo merupakan yang terendah pada kondisi bullish. Pada kondisi bearish, biaya terendah dicapai ketika tidak dilakukan strategi opsi. Pada kondisi neutral, strategi short combo dan strategi bull call spread memberikan biaya terendah. Kedua strategi opsi memiliki kerugian maksimum pada saat spot price kurang dari strike price pertama dengan nilai yang berbeda-beda. Keuntungan maksimum bull call spread dan short combo terjadi pada saat spot price lebih besar dari strike price kedua. Keuntungan makimum short combo bernilai tak terhingga jika terjadi peningkatan spot price. Bull call spread lebih menguntungkan pada kondisi bearish, sedangkan short combo lebih menguntungkan pada kondisi bullish., The instability of demand and supply that occurred as a result of the Covid-19 pandemic caused the price of crude palm oil in Indonesia to increase rapidly. Hedging using an options strategy can be a solution to reduce risk if you face rising prices or bullish conditions in the future. This research uses two option strategies, namely the bull call spread and short combo strategies. Based on the calculation results, short combo costs are the lowest in bullish conditions. In bearish conditions, the lowest costs are achieved when no option strategy is implemented. In neutral conditions, the short combo strategy and the bull call spread strategy provide the lowest costs. Both option strategies have a maximum loss when the spot price is less than the first strike price by varying values. The maximum profit from the bull call spread and short combo occurs when the spot price is greater than the second strike price. The maximum profit of a short combo is infinite if there is an increase in the spot price. Bull call spreads are more profitable in bearish conditions, while short combos are more profitable in bullish conditions.
Keyword: crude palm oil, hedging, option, bull call spread, short combo, lindung nilai

Judul: Synthesis of Apatite - Chitosan Composite Using Duck Eggshell and Chitosan with Temperature and pH Control
Abstrak: Composite of apatite-chitosan was prepared by using chitosan as polymer matrix. Calcium phosphate was prepared from CaO and (NH4)2HPO4, which the ratio Ca : P had to be 1.67. Chitosan is produced by deacetilase from biopolymer chitin. Duck eggshell (95% CaCO3) as starting material was converted to be calcium oxide (CaO) through calcinations with temperature 1000oC for 5 hours. In-situ and ex-situ methods were prepared from apatite and chitosan (dissolved with acetate acid 2%). Calcium phosphate prepared for bone implantation, but it is too fragile and brittle to be implant into the body. So addition of chitosan can decrease crystalinity and increase mechanic characteristic (tougher). Composite apatite-chitosan was resulted by fast precipitation. Fast precipitation was held in a breaker glass with nitrogen atmosphere, under controlled temperature at 37oC and pH 7, in order to increase amount of hydroxyapatite. Precipitation with CaO which was dropped by (NH4)2HPO4. Hydroxyapatite and chitosan were appearing at samples with in-situ and ex-situ methods which indicating by peak matching of XRD (closed lattice parameter, crystal size), overlapping at FTIR spectra and supporting by SEM picture (homogenous and agglomerated particle). However, it still needs further research to examine biocompatibility osteoconductive degree of sample by in-vivo and in-vitro test.
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