Judul: Penentuan tarif optimal kendala individu rasional dan kesesuaian insentif pada perusahaan telekomunikasi
Abstrak: Ada dua perusahaan telekomunikasi yaitu perusahaan A dan perusahaan B. Masing-masing perusahaan memproduksi satu produk yang sama tetapi berbeda kualitas. Kualitas produk perusahaan B lebih baik dibandingkan kualitas produk perusahaan A sehingga harga produk perusahaan B lebih tinggi daripada harga produk perusahaan A. Pilihan konsumen untuk membeli produk pada suatu perusahaan hanya ditentukan oleh pendapatan konsumen dan harga produk perusahaan tersebut.
Keyword: 

Judul: Analisis struktur Modal yang Optimum pada Perusahaan Telekomunikasi yang Terdaftar di BEI
Abstrak: Capital structure is an equalization between the use of own capital and the loan. Weighted average cost of capital (WACC) concept is used on the condition when the company apply combination of several sources of fund. From this research it is known that the telecommunication industry has capital structure which is dominated by Common Stocks with an average proportion of 54.21%, bonds about 38,90% and the rest is preferred stock 9,81%. From the WACC calculation, it can be seen that the telecommunication industry has the WACC about 12,41%. while, based on the calculation of firm value, the company in sector of telecommunication industry has average firm value which is higher than the book value. By the WACC and firm value calculation, PT. Indosat Tbk. has capital structure that’s optimum, and PT. XL Axiata Tbk. does not quiet optimum. It is expected that PT. XL Axiata Tbk. can minimalized the cost of capital to increasing the firm value. Meanwhile, the WACC concept does not apply to PT. Telekomunikasi Indonesia Tbk.
Keyword: optimal capital structure, cost of capital, firm value, capital Structure

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.
Keyword: