Judul: Produktivitas Budidaya Cacing Sutra (Oligochaeta) dalam Sistem Resirkulasi Menggunakan Jenis Substrat dan Sumber Air yang Berbeda
Abstrak: Tubificid worm have been used as live food which is important for ornamental fish production as well as other fish hatchery. This is because it has high protein content up to 52,49%. Many research have been done regarding tubificid culture, the result however still lower than that of natural production. The aim of this research was to increase productivity of tubificid worm in a recirculation system by using different types of substrate and source of water. This researching consisted of 4 treatments, i.e. ground water with sand substrate (SP), ground water with mud substrate (SL), catfish culture effluent with sand (LP), and catfish culture effluent with mud (LL). The research was done from May to August 2011 at Cibanteng, Laboratory of Fish Environment, and Laboratory of Fish Nutrition. Cultivation media was made by mixing the substrate and fermented chicken manure at ratio 1:1 , which drown in 2 cm height of water level. After 10 days drown the worm was stocked at 69 gram/m2. Culture period occurred was 60 days with addition of manure every 15 days. Biomass sampling was done every 15 days. The result of this research showed that biomass of worm cultured in LP medium is higher than in SP, SL, and LL, whereas in LL is the lowest biomass. Biomass growth of the worm in all treatment was significant at day 45th and 60th , where as the highest biomass (89,56 gram/m2) reached at day 45th on LP treatment.
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Judul: Budidaya Cacing Oligochaeta dengan Padat Penebaran Berbeda pada Sistem Sirkulasi dengan Pergantian Air
Abstrak: Oligochaeta worm contain protein of 65%, fat 15%, and carbohydrate 14%, therefore very well when given to the fish larvae during nursery period. But, the availability of oligochaeta worm are very limited especially in Belitung which has 10 hatchery. So that, it needs oligocheta worm cultivation to meet the demand. The research used closed system which mean wasted water from. The purpose of this research to determine the best stocking denstiy of oligochaeta worm between 2600,3600, and 4600 indvidual/m2 with the system based on the biomass, growth rate,and economic efficiency. The research was perfomed in April until August 2011 at the Balai Benih Ikan Air Tawar Belitung Timur. The medium used are a mixture of fine mud and chicken manure. The worm was spread and fermentation manure chicken fertilized added every day about 1 kg/m2. The worm was cultured during 60 days and took as samples every 10 days. The observation indicated that the maintanence of oligocaeta worm with closed system produced the level of ammonia contain was higher and dissolve oxygen contai was lower than using opened system. In this condition, the worm was able to survived even thought feeding habit and reproduction is inhibited. Highest population and biomass occured on 50th day with stocking density 4600 individual/m2 as much as 255091.61 individual/m2 and 1275.46 g/m2. Highest biomass growth rate occured in 4600 individual/m2 as much as 25.05 g/m2/day. Stocking density 4600 individual/m2 got the profit as much as Rp 5 828 525, R/C ratio 1.04, PP for 6.13 years, BEP (Rupiah) Rp 154 585 260 and BEP (units) 937 kg, and HPP Rp 72 389.
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Judul: Monotonicity Properties of Trapezoid Sum Sequence on Class of Nonconvex and Nonconcave Function
Abstrak: Bernhard Riemann mendefinisikan integral tentu sebagai luas daerah di bawah kurva dari suatu fungsi real taknegatif pada sebuah interval yang tertutup dan terbatas. Beberapa alternatif yang dapat digunakan untuk menghampiri luas tersebut adalah Darboux sums melalui penjumlahan beberapa luas persegi panjang dan trapezoid sum melalui penjumlahan luas trapesium. Trapezoid sum lebih baik dalam menghampiri nilai integral untuk fungsi-fungsi yang well-behaved daripada Darboux sums. Untuk fungsi f yang bernilai real dan kontinu pada interval [a,b], f terintegral Riemann jika dan hanya jika f terintegral Darboux. Pada tesis ini ditunjukkan bahwa f terintegral Riemann jika dan hanya jika f terintegral secara trapesium. Misalkan f adalah suatu fungsi bernilai real yang kontinu pada interval [a,b]. Untuk setiap partisi P_n yang membagi [a,b] menjadi n subinterval dengan jarak yang sama, dibentuk trapezoid sum T_n (f) yang merupakan jumlah luas n trapesium sebagai pendekatan dari nilai integral f pada [a,b]. Jika f adalah fungsi konveks maka barisan trapezoid sum {T_n (f)} bersifat monoton turun dan akan bersifat monoton naik jika f fungsi konkaf. Fokus tesis ini adalah sifat kemonotonan barisan {T_n (f)} untuk fungsi f yang nonkonkaf dan fungsi f yang nonkonveks. Pada tesis ini dibuktikan sifat monoton turun dari {T_n (f)} secara generik tidak terjadi pada kelas fungsi nonkonkaf f, serta secara generik, barisan itu juga tidak monoton naik pada kelas fungsi nonkonveks. Meskipun demikian, sifat generik mengakibatkan bahwa untuk sebarang fungsi f baik di kelas fungsi nonkonkaf maupun nonkonveks, terdapat fungsi g yang menghampiri f sedemikian sehingga ekor barisan {T_n (g)} bersifat monoton. Ditunjukkan pula bahwa himpunan fungsi naik nonkonkaf dengan {T_n (f)} yang tidak monoton turun dense terhadap kelas fungsi naik nonkonkaf f. Hal tersebut juga ditunjukkan untuk himpunan fungsi turun nonkonkaf terhadap kelas fungsi turun nonkonkaf. Lalu, dibuktikan bahwa himpunan fungsi naik nonkonveks dan himpunan fungsi turun nonkonveks dengan {T_n (f)} yang tidak monoton naik, berturut-turut dense terhadap kelas fungsi naik nonkonveks dan turun nonkonveks. Himpunan-himpunan yang dense tersebut mengartikan bahwa setiap fungsi f pada kelas-kelas tersebut, dapat dihampiri oleh suatu fungsi g yang bersesuaian dengan kelas-kelas tersebut sedemikiam sehingga barisan {T_n (g)} tidak monoton., Bernhard Riemann defined definite integral as an area under the curve of a real nonnegative function on a closed bounded interval. The alternatives that can be used to estimate the area are Darboux sum which is sum of rectangular areas and trapezoid sum which is sum of trapezium areas. Trapezoid sum is better than Darboux sum as approximations toward the integral of well-behaved functions. Let f be a real valued continuous function on interval [a,b], f is Riemann integrable if and only if it is Darboux integrable. In this master’s thesis, it showed that f is Riemann integrable if and only if it is trapezium integrable. Let f be a real valued continuous function on interval [a,b]. For each partition P_n that divides the interval [a,b] into n equal length subintervals, defined trapezoid sum T_n (f) which is the total of n trapezium areas as an approach of integral value f on [a,b]. If f is a convex function then the trapezoid sum sequence {T_n (f)} is decreasing
Keyword: monotonicity, nonconcave, nonconvex, trapezoid sum