Judul: Potency estimation, carrying capacity and exploitation for sustainable simping population (Placuna placenta, Linn 1758) management
Abstrak: Exploitation activity using garok and habitat change would damage the availability of simping resources. This pattern was shown as the size and biomass of Kronjo’s fishermen catchment has been decreasing. In order to conduct the sustainably usage, a study of simping stock potency, exploitation level, recovery ability and carrying capacity of exploitation area is needed. These research conducted at Kronjo Bay from March-September 2008. Main topic are 1) distribution of simping population, 2) fishing intensity and 3) turnover rate and turn over time, production, biomas, P/B ratio, production capacity. Data analysis used statistic descriptive, one way anova and simulation model using Microsoft excel. The result shows that parameters COD, DO and potential TSS distracted the simping survival, while other parameters still supported the simping survival. Abundance stock potency was high at zone 2, zone 1 and zone 3. Stock biomass potency was also high at zone 2, zone 3 and sone 1. The recovery ability of the stock at zone 1 was 18,20 g.m-2.day-1, zone 2 was 19,37 g.m-2.day-1, and zone 3 was 8,76 g.m-2.day-1. Total growth during exploitation stage at zone 1 was 56 g.m-2.day-1, zone 2 was 55,57 g.m-2.day-1 and zone 3 was 26,87 g.m-2.day-1. While exploitation at zone 1 was 63,5 g.m-2.day-1, zone 2 was 79,6 g.m-2.day-1and zone 3 was 20,8 g.m-2.day-1. Biomass production ratio (time recovery) (B/P ratio) at zone 1 was 3,1 days, at zone 2 was 2,9 days and zone 3 was 3,1 days. From the result above, it is concluded that in zone 3, there is a potency of sustained simping usage, while at zone 1 and 2, there would need a conservation activity in order to achieve the growing biomass to balance the exploitation. Exploitation carrying capacity was high at zone 2 and 1, while at zone 3, the exploitation carrying capacity was lower. In production operation wise, the approaching of carrying capacity, catchment quota, catchment intensity and catchment area management should be conducted as follow up steps of management.
Keyword: Potency Estimation, Carrying Capacity, Simping Population, Placuna placenta

Judul: Exploitation status of the small-pelagic fish resources in Maluku waters and its fishing capacity
Abstrak: The potential for the Maluku’s pelagic fishery resources is moderately exploited; hence, small-pelagic fishery development is considerably strategic. The development of the small-pelagic fishery is complex due to involvement of stakeholders in the resources utilization, and the unique characteristics of marine fish resources. Since 1999, fishing capacity issue has become growing concerns in world fisheries. Excessive fishing capacity can contribute substantially to overfishing, degradation of marine fishery resources, and significant economic waste. In line with fishing capacity, this research was conducted to analyze exploitation status of the small-pelagic fish resources in Maluku waters based on fishing capacity. Research location was the WPP-714 Banda Sea, particularly focused on area of the Central Maluku Regency and Ambon City. Collected data were analyzed by using bioeconomic approach of Gordon-Schaefer model, data envelopment analysis (DEA), technique of linear goal programming (LGP), stochastic production frontier analysis (SPF), and strategic environment analysis. Results showed that at maximum sustainable yield (MSY); production was 57,589.57 tones per year, fishing effort 7,945,48 trips, biomass 480,715.12 tones, and economic rent Rp 200,499,420,000. Six out of the 22 decision-making units (DMU) were fully efficient. The lowest capacity utilization in small-pelagic fishery was found in DMU-1988, which was 76%. There was indication of over capacity on the small-pelagic fishery in the period of 1989 to 1999. The smallpelagic fishery in the east season was more efficient than that of in the west season. At temporal exploitation for the east season, allocation of purse seine was 161 units and of gillnet was 6,507 units, whereas for the west season allocation of purse seine was 13 units and gillnet 2,663 units. The affected determinants of the stochastic frontier production function were length and width of fishing gears, number of persons per vessel, investment value of fishing unit, and time spent in fishing per trip. Age of skipper, total household size of the skipper, and the skipper’s years of fishing experience significantly influenced technical inefficiency of fishing. Optimal allocation of purse seine was 251 fishing units, gillnet 10,011 units, lift net 190 units, and beach seine 32 units. Compared to the original allocation of the fishing unit, lift net and beach seine decreased very sharply by 781 units and 393 units, respectively. Strategic plan was designed under a vision of “pelagic fishery development based on fishing capacity and efficiency for people welfare”. This vision is aimed at balancing level of fishing fleets with the sustainability of the marine fish resources in Maluku. To achieve this goal, some environmental factors associated with fishing capacity management were identified and used for developing strategic plan.
Keyword: fishing capacity, Banda sea, Ambon City, strategic environment analysis

Judul: Kombinasi algoritma sha 1 dan algoritma rsa untuk membentuk tanda tangan digital
Abstrak: Tanda tangan digital termasuk ke dalam teknik kriptografi yang memanfaatkan teknologi kunci publik (enkripsi asimetris). Tanda tangan digital dapat dibuat dengan mengkombinasikan teknik hashing (untuk membentuk message digest dari pesan asli) dan enkripsi asimetris (untuk membentuk kunci publik dan kunci privat). Teknik hashing yang digunakan adalah teknik rashing satu arah dengan menggunakan algoritma SHA 1, sedangkan algoritma RSA digunakan untuk enkripsi asimetris Tulisan ini bertujuan untuk mempelajari, menganalisis, dan mengimplementasikan pembentukan dan verifikasi tanda tangan digital menggunakan dua metode, yaitu dengan mengkombinasikan algoritma SHA 1 dan algoritma RSA dan dengan menggunakan algoritma RSA saja. Analisis yang dilakukan pada kedua algoritma ini meliputi analisis algoritma, dan analisis hasil implementasi. Analisis terhadap algoritma SHA | menunjukkan bahwa algoritma ini memiliki kompleksitas O(n) untuk kasus terburuk. Sedangkan untuk pembentukan kunci publik dan kunci privat dengan algoritma RSA diperlukan beberapa algoritma pendukung, yaitu algoritma Miller Rabin, Witness, Euclid, dan Extended Euclid. Semua algoritma pendukung tersebut memiliki kompleksitas waktu yang sama, yaitu O(k), dengan adalah panjang representasi bit bilangan bulat. Kompleksitas waktu yang didapatkan untuk proses pembentukan tanda tangan digital dengan kedua metode ini adalah sama yaitu O(nk). Untuk proses verifikasi, kompleksitas waktu yang didapatkan dengan menggunakan kombinasi dua algoritma adalah O(1 + k) dan untuk algoritma RSA adalah O(n + k). Pada proses pembentukan tanda tangan digital menggunakan kombinasi dua algoritma yang ditandatangani adalah message digest yang dihasilkan oleh algoritma SHA 1, sedangkan pada algoritma RSA yang ditandatangani adalah pesan itu sendiri. Dari hasil implementasi didapatkan untuk proses pembentukan tanda tangan digital menggunakan kombinasi dua algoritma lebih cepat dibandingkan dengan menggunakan algoritma RSA saja untuk file-file yang berukuran besar, dst
Keyword: Tnda Tangan Digital, Teknik Kriptografi, Enskripsi Asimetris