Judul: Aspek biologi reproduksi ikan beloso (Glossogobius giuris) di Perairan Ujung Pangkah, jawa Timur
Abstrak: Penelitian ini bertujuan untuk mengetahui aspek-aspek reproduksi ikan beloso Glossogobius giuris di Perairan Ujung Pangkah, Jawa Timur. Hasil penelitian diharapkan dapat menjadi bahan informasi dalam upaya pengelolaan dan pemanfaatan perairan tersebut. Pengambilan ikan sampel dilakukan berdasarkan lokasi penangkapan ikan beloso oleh nelayan setempat dengan menggunakan gillnet, bubu dan jager selama 6 bulan yaitu dari bulan juli sampai dengan Desember 2005. Ikan sampel diawetkan dengan formalin 10% dan pengamatan dilakuakn di Laboratorium Ekobiologi Fakultas Perikanan dan Ilmu Kelautan dan Laboratorium Biologi Hewan Pusat Studi Ilmu Hayati Institut Pertanian Bogor.
Keyword: 

Judul: Studi kebiasaan makanan ikan beloso (Glossogobius giuris) di perairan ujung pangkah, Jawa Timur
Abstrak: Ikan beloso G. giuris hidup di laut dan di sungai-sungai (Weber and de Beaufort, 1953). Tergolong jenis ikan karnivor makanannya berupa anak-anak kepiting, udang-udang kecil, ikan-ikan kecil dan lain-lain. Upaya pengelolaan terhadap sumberdaya ikan beloso belum dilakukan secara optimal sehingga informasi mengenai pemanfaatan dan pengembangannya masih kurang. Oleh sebab itu, berbagai informasi mengenai aspek biologis dan ekonomisnya sangat diperlukan. Salah satu aspek biologis yang penting yaitu mengenai kebiasaan makanan ikan beloso. Tujuan penelitian ini adalah untuk mengetahui kebiasaan makanan ikan beloso dengan melihat komposisi jenis makanannya. Hasil penelitian ini diharapkan dapat dijadikan dasar untuk pengelolaan perikanan ikan beloso G. giuris, baik pemanfaatan maupun budidayanya. Penelitian ini dilaksanakan dari bulan Januari 2002 sampai Juni 2002. Analisa contoh dilakukan di laboratorium Ekobiologi Fakultas Perikanan dan Ilmu Kelautan dan di laboratorium Biologi Hewan, Pusat Studi Ilmu Hayati, Institut Pertanian Bogor. Ikan contoh yang diteliti merupakan hasil tangkapan nelayan di Perairan Ujung Pangkah, Jawa Timur. Analisa data menggunakan persentase konsumsi pakan relatif (ISC=SCW/BWX100%), Indeks bagian terbesar (IP = ((Vixoi)/V,XO) X00%)), dan Indeks similaritas (B=Χ - Χ/Σ + Χα X 1 Ikan contoh yang diambil di Perairan Ujung Pangkah berjumlah 259 ekor terdiri dari 98 ekor ikan jantan dan 161 ekor ikan betina, membentuk 10 selang kelas panjang dengan kisaran antara 85 mm sampai 254 mm, jumlah terbanyak terdapat pada selang kelas 153-169 mm dan berat tubuh berkisar antara 5,01 gram sampai 95,69 gram. Berdasarkan hubungan panjang-berat pada ikan beloso jantan dan betina didapatkan nilai b>3 bersifat allometrik positif artinya pertumbuhan berat lebih cepat dibandingkan pertumbuhan panjang. Persentase konsumsi pakan relatif tertinggi terdapat pada bulan Februari untuk ikan beloso jantan dan betina, sehingga ikan beloso pada bulan Februari diduga aktif mencari makan. Berdasarkan nilai IP makanan ikan beloso didapatkan nilai IP tertinggi pada Crustacea yang merupakan makanan utama (ikan jantan 92,01%, dan...
Keyword: 

Judul: The Effects of Variance of Interest rate to Variance of Annuity Future Values
Abstrak: Time value of money is a concept that refers to the difference of the value of money due to time difference. The value of money for present time would not be the same as the value of money in the future. The value of money for present time is called as Present Value (PV) of the money and the value of money for future time is called Future Value (FV) of the money. Determination the value of money, for present and future time, depends on the time and rate of return. The value of money is determined by several factors such as inflation, fluctuation of interest rates, and government policy in securities and taxation. Due to fluctuation of the value of money we need a FV formulation, it is useful for knowing whether an investment can be profitable or not, and this information is useful also in budget analysis. Annuity is defined as a series of payments made for a specific period. The payment, fixed or varied, can be made at the beginning or at the end of the period. Annuity paid at the beginning of the period is called annuity-due and annuity paid at the end of the period is called immediate annuity-certain. The accumulated value of the annuity after few years later is called as a final value or a future value. Burnecki et al. (2003) have discussed about the FV of a fixed-rate annuity in which payments are made according to the arithmetic or geometric series. They have also examined FV for annuities in which payments are made according to arithmetic or geometric series with random rates of interest. This paper examines FV for annuity-due in which payments are made according to arithmetic or geometric series with interest rates as a random variable, which is normal distribution ,  . Future value formula is expressed in recursive form. FV for annuity-due which payments are made according to the arithmetic or geometric series with random rates of interest is calculated by theoretical way and simulation way. The random rates of interest is denoted as k k i  i  , where k i an independent random variable; i is a constant and k  is a random variable which has normal distribution ,  . By using the determined parameters, a sequence of random rates of interest are generated for theoretical calculation. Meanwhile for the simulation, the random rates of interest is generated 1000 times for the simulation. The generated data give mean value, variance, and standard deviation. Moreover, error of mean value, variance, and standard deviation from the theoretical and simulation results are calculated. Error calculation uses Symmetric Mean Absolute Percentage Error (SMAPE). The smaller the value of SMAPE is the more accurate the simulation. The interest rate variances are varied from 0.000036 to 0.0001 to study the relationship between variance of rates of interest and variance of future value. The theoretical and simulation results show that when the variance of random rates of interest increases, then the variance of FV increases linearly. FV of the annuity-due in
Keyword: