Judul: Biofotovoltaik Menggunakan Spirulina platensis : Pengaruh Perbedaan Media Kultur
Abstrak: Pemanfaatan energi matahari pada saat ini sudah cukup maju, namun penggunaan bahan–bahan sel surya konvensional masih memberi dampak buruk untuk lingkungan. Dengan memanfaatkan kemampuan fotosintesis pada organisme biologis untuk menghasilkan listrik dapat memberikan alternatif tambahan untuk menghasilkan energi listrik yang lebih ramah lingkungan. Pada penelitian ini, Spirulina platensis dipilih sebagai organisme yang dimanfaatkan untuk memperoleh energi listrik karena keberadaannya yang cukup mudah ditemukan dan waktu pertumbuhannya yang relatif singkat. Pemberian media kultur Spirulina platensis dengan perbedaan kandungan nitrat dan fosfatnya dapat memberikan informasi media kultur mikroalga yang bisa menghasilkan energi listrik lebih baik. Hasil pengambilan data dari piranti biofotovoltaik menunjukkan energi listrik yang dihasilkan dari kedua media cukup setara, namun kemampuan pertumbuhan selnya yang berbeda dan puncak daya tertingginya diperoleh dari kultur dengan media Walne., Utilization of solar energy at this time is quite advanced, by using the conventional photovoltaic solar cell materials still has a negative impact on the environment. By taking advantage of photosynthesis abilities from biological organisms to generate electricity can provide an additional alternative to obtain environmentally friendly energy. In this study, Spirulina platensis was chosen as the organism used to obtain energy by the photosynthesis abilities because of its availability and has relatively short time growth. Differentiating nitrate and phosphate content from the planting medium for Spirulina platensis cultivate can provide information at its ability to produce electrical energy. The results of data collection from biophotovoltaic devices show that the electrical energy produced from the two media is quite equivalent, but it has difference ability to survive in cultivation and the cultuvation with Walne medium has highest peak of power.
Keyword: Biophotovoltaic, Spirulina platensis, Photosynthesis system

Judul: Sel Surya Hibrid Organik/Anorganik berbasis Bulk Heterojunction Nanopartikel TiO2 dan Klorofil dari Spirulina plantesis
Abstrak: Pengembangan besar-besaran untuk mencari sistem pembangkit listrik secara ekonomis untuk memanfaatkan sinar matahari dalam bentuk sel surya masih dilakukan hingga saat ini, namun sel surya konvensional masih terbilang mahal dan dapat memberi dampak buruk untuk lingkungan. Dengan memanfaatkan kemampuan ekstrak klorofil organisme biologis untuk menghasilkan listrik dapat memberikan alternatif tambahan untuk menghasilkan listrik yang lebih ramah lingkungan. Pada penelitian ini, Spirulina plantesis dipilih karena keberadaannya yang cukup mudah ditemukan dan mengandung klorofil yang baik. Selain itu counter-elektroda yang digunakan diperoleh dari jelaga api dan karbon pensil 8B yang sangat mudah didapat. Pemberian variasi counter-elektroda dapat memberikan informasi arus, tegangan, dan daya keluaran listrik yang dihasilkan dari sel surya. Daya keluaran maksimum dan efisiensi yang diperoleh sel surya counterelektrode jelaga berturut-turut sebesar 338,011 × 10-9 Watt dan 0,01%, sementara daya keluaran maksimum dan efisiensi sel surya counter-elektroda karbon pensil 8B berturutturut sebesar 204,254 × 10-9 Watt dan 0,00006%., Massive development to find power generation systems economically to utilize sunlight energy in the form of solar cells is still being done today, but conventional solar cells are still quite expensive and can have a bad impact on the environment. Utilizing the ability of biological organisms' chlorophyll extracts to generate electricity can provide an additional alternative to generating more environmentally friendly electrical energy. In this study, Spirulina plantesis was chosen because of its presence which is quite easy to find and contains good chlorophyll. In addition, the counter-electrodes used are obtained from soot and 8B pencil carbon which are very easy to obtain. The provision of counter-electrode variations can provide information on the current, voltage, and power output of electricity generated from solar cells. The maximum output power and efficiency obtained by the soot counterelectrode solar cell was 338,011 × 10-9 Watts and 0,01%, respectively, while the maximum output power and efficiency of the pencil 8B carbon counter-electrode solar cell was 204,254 × 10-9 Watts and 0,00006% respectively.
Keyword: bulk heterojunction solar cell, Spirulina platensis, iodide/triiodide

Judul: Truncated Stop Loss as a Optimal Solution of Reinsurance Agreement in One-Period Model
Abstrak: Reinsurance is one of risk management efforts of an insurance company, which is called the cedent. Similar with insurance, reinsurance constitutes the cedent to pay the premium. We consider one-period reinsurance model and derive a rule which minimizes the ruin probability of the cedent for a fixed reinsurance premium. Therefore, it is needed to construct an optimal reinsurance agreement for the cedent. The premium is calculated according to four different principles, i.e. economic, generalized zero-utility, Esscher, and mean-variance principles. Stop loss is a reinsurance contract which protect the insurance company for losses that exceed a certain amount. The result of this research shows that a truncated stop loss is an optimal agreement in the class of all reinsurance contracts with various premiums calculated using above mentioned principles.
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