Judul: Simulation Study of Comparison Between Generalized Linear Regression Model and Copula Based Regression
Abstrak: Ordinary Least Square (OLS) merupakan regresi yang umum digunakan untuk menganalisis hubungan antara peubah respon dan peubah penjelas. Namun, asumsi-asumsi pada regresi OLS kurang cocok diaplikasikan di bidang aktuaria. karena seringkali peubah respon tidak menyebar normal. Generalized Linear Model (GLM) melonggarkan asumsi OLS di mana peubah respon dari keluarga eksponensial. Selain GLM, dikenal model regresi berbasis copula yang diperkenalkan oleh Sklar pada tahun 1959. Beberapa keunggulannya adalah, tidak ketat terhadap asumsi sebaran, dapat menjelaskan hubungan yang tidak linear, dan mudah membangun sebaran bersamanya. Dalam karya ilmiah ini, digunakan data bangkitan dengan beberapa sebaran untuk menunjukkan model mana yang lebih baik dalam memodelkan hubungan antara peubah respon dan peubah penjelas. Hasil menunjukkan bahwa regresi copula memodelkan hubungan lebih baik dibandingkan dengan model GLM dalam kondisi data menyebar keluarga eksponensial dengan kondisi korelasi antar peubah penjelas dan peubah respon tinggi ataupun rendah.
Keyword: Ordinary Least Square, Generalized Linear Model, Regresi copula.

Judul: Pendugaan Kerugian Agregat dengan Model Regresi Berbasis Copula.
Abstrak: Pendugaan kerugian agregat dari sebuah portofolio asuransi merupakan hal yang sangat penting bagi keputusan aktuarial, seperti menentukan harga kontrak asuransi dan menghitung premi. Kerugian agregat merupakan total kerugian polis yang harus ditanggung oleh perusahaan pada periode waktu tertentu. Kerugian polis dapat dihitung berdasarkan rata-rata besarnya klaim dan banyaknya klaim. Dalam karya ilmiah ini, model regresi marjinal dari rata-rata besarnya klaim dan banyaknya klaim menggunakan model linear terampat (generalized linear model). Pada model linear terampat, peubah respon dipengaruhi oleh peubah penjelas yaitu pendapatan per kapita dan kepadatan penduduk. Penelitian sebelumnya menggunakan asumsi peubah rata-rata besarnya klaim dan banyaknya klaim saling bebas, namun pada kenyataannya kedua peubah ini tidak saling bebas. Oleh karena itu, digunakan model regresi berbasis copula untuk mengatasi asumsi saling bebas. Model regresi berbasis copula terbaik dipilih berdasarkan nilai logaritma kemungkinan terbesar dan mean square error terkecil. Dalam karya ilmiah ini, data yang digunakan adalah data asuransi kendaraan di Massachusetts dari tahun 1993 sampai 1997. Model regresi berbasis copula terbaik yang dapat memodelkan kerugian agregat pada asuransi ini adalah copula Gumbel sehingga diperoleh pendugaan kerugian agregat untuk periode 1998 sebesar $73831.95.
Keyword: kerugian agregat, regresi copula, model linear terampat, rata-rata besarnya klaim, banyaknya klaim

Judul: Application of phycocyanin from microalgae Spirulina platensis as light harvesting in anatase TiO2 nanoparticle solar cell.
Abstrak: The dye sensitized solar cell (DSSC) has been assemblied used hybrid titanium oxide (TiO2) film/phycocyanin. The TiO2 film was synthesized by sol gel method with titanium chlorida (TiCl4) as precursor by hydrolysis used sulfuric acid (H2SO4). Furthermore, it calcinated for 2,5 hours in variation of annealing temperature (400oC, 600oC, 800oC, dan 1000oC). In XRD patterns exhibited which annealing temperature at 400oC to 800oC were anatase phase all. When annealed at temperature 1000oC, it caused phase transformation from anatase to rutile. The crystals size according to XRD patterns were 13,75 nm, 20,79 nm, 25,25 nm, 48,88 nm and particle size from SEM images were 43,06 nm, 44,91 nm dan 64,99 nm, 80,40 nm, respectively. The crystals and particle size increased with annealing temperature. The film thickness influenced material absorption. The optical measurement of TiO2 film and TiO2/phycocyanin hybrid film used UV-Vis spectrophotometer. Additional phycocyanin caused peak width of absorbed region from ultraviolet to visible region. The band gap energy of TiO2 can be calculated using the cut off wavelength obtained from the absorbance spectrum of a nanoparticles TiO2 films. Based on intersection between linear and energy (hv) axis. In this study just limited for anatase phase. It was caused anatase band gap is wider than rutile phase. That’s meaningful for solar cell application such as dye sensitized solar cell (DSSC). The absorption coefficient average at difference annealing temperature such as at 400oC, 600oC, 800oC were 8,1600x102, 1,7535x103 and 4,0154x102, where α < 104 include to direct transition. Band gap energy 400oC, 600oC, 800oC were 3,79 eV, 3,59 eV, and 3,35 eV, respectively. Based on this result, exhibition that band gap energy of TiO2 semiconductor film decreased with increasing annealing temperature. Spirulina platensis was cultivated in technical modification (Hastuti) with aeration under light intensity about 3000 lux. The cell density (stationer phase) for eighth day which OD value was more than 0,5. It means, the culture can be harvested. In 80 liters Spirulina platensis culture have been produced biomass dry about 10,46 gram and extracted phycocyanin in dry powders was 5,50 gram. The phycocyanin absorption spectrum at the wavelength of 619,36 nm (visible region) which had relaxation energy was 2,945 eV. The emission peak at the wavelength of 708,55 nm with relaxation energy about 2,793 eV. The Stokes shift based on difference energy absorption and emission calculated about 0,152 eV. Both of this showed phycocyanin can absorbed and radiated the sun light which received. This choice characteristic pigment was a good one related to sensitizer in solar cell application. Integration between light harvesting protein and TiO2 semiconductor surface had important role in improving of output as solar cell materials. The presence of carboxylate group (-COOH) made pigment be more efficient was due to anchored to the surface of TiO2 ampoter. The phycocyanin pigment had carboxylate group which reacted with TiO2 surface formed ester. The carboxylate group increased of dye electronics couple from excited state (p anti bonding orbital) to semiconductor acceptor state (TiO2 conduction band). The samples which made based on annealing temperature variation formed be solar cell respectively. Furthermore, cells be assembled for
Keyword: anatase, dye sensitized solar cell, efficiency, gap energy, phycocyanin