Judul: Pertumbuhan dan kelangsungan hidup benih ikan sinodontis Synodontis eupterus pada kepadatan yang berbeda
Abstrak: n a good environmental condition and adequate quantity of food, an increase of stocking density will increase yield. This experiment was aimed to obtain information about the most optimum stocking density of sinodontis nursery culture. The initial size of sinodontis fry was 2,54+0,11 cm in length and 2,97+0,43 g in weight, which was obtained from a sinodontis farmer at Pagelaran, Bogor, West Java. Prior to experiment, the fry was adapted in the aquaria with a size of 60x29x33 cm which had been filled with 20 ℓ of water. The fry was then cultured at 3 different stocking density treatments. 3, 6, 9 fry/ℓ with 3 replications for a period of 40 days. The fry fed a Limnodrilus sp. twice a day at satiation. Substitution of water exchanged twice a day in the morning and on the afternoon with a rate of 2x30% a day. The result indicated that stocking density did not significantly affected fish survival, specific grow rate, growth of absolute length and coefficient of variation (p>0.05). But when viewed from the economic efficiency, density of 9 fry/ℓ give the best results with the R/C ratio is greatest.
Keyword: 

Judul: Produksi dan Analisis Usaha Pendederan Ikan Sinodontis Ukuran 1 inci dengan Padat Tebar Berbeda
Abstrak: The research aimed to determine optimal stocking density of Synodontis eupterus at body length of 1 inch reared in aquarium. The treatment in this research was three levels of fish stocking density namely 15, 18, and 21 fishes/liter, and water exchange of 100% a day. A control treatment was stocking density of 15 fishes/liter and 60% water exchange a day. The body length mean of fishes used was 2.55 ± 0.03cm. The fishes reared in 25x25x25cm3 aquarium filled with 8L of fresh water, for 40 days. The fishes were fed with bloodworm in the morning and afternoon. The results showed that difference in treatment was not followed by the differences in survival rate. On the 15 fishes/liter density, a 50% water exchanges could increase the growth, compared to the control. However, increasing the stocking density followed by decreasing of the specific growth rate, daily weight growth, the absolute length growth and feed efficiency. In terms of economic aspect, the 21 fishes/liter stocking density was the highest profit value.
Keyword: 

Judul: Analisis dan Implementasi Certificate Authorities (CA) pada Public Switched Telephone Network (PSTN)
Abstrak: Secure Telephone Protocol has ability to authenticate involved party and keep the secrecy of the message sent over the protocol. The secrecy of the message archieved by using symmetric key cryptographic scheme, and authentication archieved using public key cryptographic scheme. One of several party involved in the protocol and hold an important function called Certificate Authorities or CA. CA responsible for generating public key pair for other party involved in the protocol. When CA generates public key pair, several primitive cryptographic scheme used for guarantee the security of the key. Two of them are hash function SHA-1 and El-Gamal public key scheme embedded in Digital Signature Algorithm scheme. The prototype implementing the scheme above developed using Java programming language with JCE addition from Bauncy Castle. The analysis towards implemented prototype indicates that the prototype still has some flaws to be implemented in real world.
Keyword: