Judul: Perkembangan Gonad Ikan Bilih ( Mystacoleucus padangenis Blkr) dalam Kondisi Pakan Alami dan Buatan
Abstrak: The bilih fish (Mysincolez~cuspndangensiBs lkr) is a native and endemic fish living in open water of Singkarak Lake, West Sumatera. Extensive and unselected catching of up to one ton per day threatens the fish population and endangers its conservation. In the effort to conserve the bilih fish a research had been conducted exsilo at the Seameo Biotrop laboratory in Bogor from September 1997 to Jan~~a1r9i9 8. The objective of this research is to study the effect of natural and artificial feeds (phytoplankton and pellet, respectively) on the growth pattern, the development of gonads and oocytes, the gonadosomatic indexes and fecundity of the bilih fish. Eighty four bilih fish (67 males and 17 females) were divided into two treatment groups of 42 each. The first group was treated with natural feed (phytoplankton) containing 27.89 percent protein and the second group was treated with artificial feed containing 42 percent protein. One sample of two fish each was randoinly taken every two weeks for observation, measurement and analysis. Results of this research revealed that the growth pattern of the bilih fish differs between the inale and female fish under natural feeding but not under artificial feeding conditions. Under natural feeding condition the length and weight of the female and inale bilih fish ranged from 86.00 to 101.75 mm and 5.23 to 8.15 grams, 75.00 to 96.00 mm and 3.12 to 6.35 grams , while under artificial feeding it ranged from 87.00 to 120.05 rnm and 6.01 to 17.01 grams, 78.15 to 108.95 mm and 4.76 to 13.50 grains respectively. Under natural feeding the growth pattern for females and males were negative allometric, positive allometric, whereas under artificial feeding they were isometric. Under natural feeding the female gonads reached its maximum maturity at stage 111 and the male ones at stage IV, whereas under artificial feeding the female and male gonads reached maximum maturity at stage IV. The gonadosomatic indexes of females and males under natural feeding ranged from 1.01 to 9.73 percent and 0.88 to 6.18 percent, and under artificial feeding it ranged from 1.95 to 10.64 percent and 4.18 to 7.26 percent respectively. The total fecundity under artificial feeding were between 4.057 to 11.349 grains. The oocytes development was an asinchronism type with a tendency of partiel spawner. It is generally concluded that artificial feeding with high (42%) protein content promotes growth, gonadal development and fecundity of the bilih fish better than the natural feeding with a lower (27.89%) protein content.
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Judul: Studi aspek reproduksi ikan bilih Mystacoleucus Padangensis ( Blkr ) di danau Singkarak, Sumatera - Barat
Abstrak: Ikan Bilih memiliki arti ekonomi yang cukup penting bagi masyarakat di sekitar Danau Singkarak karena jumlah populasinya yang cukup tinggi dan merupakan jenis ikan yang paling dominan di Danau Singkarak. Tujuan penelitian adalah untuk mengetahui kebiasaan pemijahan, potensi reproduksi dan beberapa aspek biologi reproduksi serta kondisi lingkungan danau. Penelitian ini dilaksanakan pada Bulan Juni sampai Agustus 1987, dengan waktu pengambilan contoh sekali 2 minggu. Pengambilan contoh ikan Bilih dilakukan di lima stasiun yaitu di muara S. Sumpur, muara S. Paninggahan, muara S. Sumani, hulu S. Ombilin dan daerah agak ke tengah danau. Alat tangkap yang digunakan adalah jala, jaring dan alahan. Ikan betina yang tertangkap lebih dari 50% berukuran antara 84,5 96,5 mm dan 3,95 9,95 gram jantan banyak terdapat pada ukuran 60,5 sedang ikan 72,5 mm dan 0,95 -3,95 gram. Sebagian besar ikan-ikan betina ini telah mencapai TKG III. Jumlah ikan betina dan jantan keseluruhan 3:1. IKG berkisar antara 2,9- 10,7(%); sedangkan ikan TKG IV mempunyai IKG antara 5,2 - 13,7 (%). Diameter telur-telur ikan Bilih yang telah berkuning telur terdiri dari 2 kelompok ukuran yaitu 0,25 mm dan 0,63 mm. Pertumbuhan ikan Bilih selama proses pematangan gonad bersifat allometric negatif. Fekunditas berkisar antara 5945 12.627 butir. Faktor kondisi rata-rata sebesar 1,15.
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Judul: Penerapan teknik watermarking untuk penandaan hak cipta pada peta vektor dengan format DXF
Abstrak: Drawing Interchange Format (DXF) is one of the general file in the field of the vector image commonly used for making maps. The DXF format is a tagged data representation of all the information contained in an AutoCAD drawing (DWG) file. Tagged data means that each data element in the watermark is preceded by an integer number called the group code. The study was carried out because there is still no tools of labeling the copyright on digital mapping using DXF file. This study aims to generate an application for copyright labeling on vector map with DXF format that can be applied to any types of spatial objects in the map. The technique used is changing the code inside the vector image. The insertion of the watermark is done by utilizing ENTITIES section by multiplying objects for sets of binary values. The results showed that the image after the watermarking insertion process is the same as the original vector image. Embedded watermark is resistant to rotation and scaling, however it has the possibility of one-third to be broken in the attack on specific object. This study has successfully implemented watermarking technique for copyright labeling on the vector map with DXF format.
Keyword: Drawing Interchange Format, Robust Watermark, Tagged Data, Vector Image, Watermarking