The Behavior of Slab-Column Connections with Modified Shear Reinforcement under Cyclic Load

Generally, slab-column frames show lower stiffness, drift capacity, and ductility as compared to beam-column frames. Under combined gravity and lateral cyclic loading, the lower initial stiffness and stiffness degradation lead to poor structural performance. Therefore, in the current codes, slab-column frames are recommended only for Intermediate Moment Frames with dual systems. The objective of this study is to modify slab-column connection details to enhance seismic performance such that the system can also be used with Special Moment Frames. Four specimens of interior slab-column connection models with the same dimensions and flexural reinforcement were tested under gravity and cyclic lateral loads. One specimen, constructed as control specimen, was designed using standard orthogonal stud rails. The other specimens used newly designed stud rails. The experimental results demonstrated that the modified stud rails significantly improved the specimens' behavior. The experimental results demonstrated that the modified stud rails significantly improve the specimen behavior. The highest ratio of initial stiffness adequacy of specimen with modified stud rail was 131.19% for risk category I/II, while the ratio of the control specimen was 97.94%. The highest relative energy dissipation ratio of specimen with modified stud rail was 33.82%, while the ratio of the control specimen was 25.94%

Evaluation of Larvae Production and Growth of Juvenile Red Tilapia NIFI F1 During the Nursery Phase

Salah satu upaya yang dapat dilakukan untuk meningkatkan kualitas genetik yaitu melalui program pemuliaan. Per-baikan karakter reproduksi dan pertumbuhan dapat digunakan sebagai indikator keberhasilan seleksi. Penelitian ini bertujuan untuk mengevaluasi produksi larva dan pertumbuhan benih ikan nila merah NIFI F1 dari induk seleksi dan kontrol. Kegiatan dilaksanakan selama empat bulan di Balai Riset Pemuliaan Ikan. Pemijahan dilakukan di kolam air tawar pada hapa 1 m x1 m. Perbandingan induk ikan nila jantan dan betina 1:1. Larva yang sudah dipanen dimasukkan pada hapa pendederan ukuran 2x2x1 m3 dengan padat tebar 125 ekor m-2 . Selama pendederan , larva diberi pakan (protein 38-42%) secara ad libitum tiga kali sehari pada bulan pertama dan selanjutnya diberi pakan dua kali sehari 15-20% dari biomassa. Pakan yang diberikan selama pendederan mempunyai protein berkisar 38-42%. Parameter yang diamati meliputi produksi larva, pertumbuhan, laju pertumbuhan spesifik, dan sintasan. Hasil penelitian menunjukkan produksi larva ikan nila merah seleksi yaitu 540±114 ekor dan kontrol 508±142 ekor. Performa pertumbuhan benih ikan nila merah seleksi menunjukkan hasil yang lebih tinggi dibanding kontrol dengan nilai pertumbuhan panjang 6,33 ±0,43cm, pertumbuhan bobot 6,60±0,52 g, laju pertumbuhan spesifik 7,33±0% g hari-1 serta sintasan 81,50±4,46%, se-dangkan populasi kontrol masing-masing 5,76±0,52 cm; 4,90±0,58 g; 4,50±0,35% g hari-1; dan 74,85±3,26%. Nilai ini menunjukkan bahwa ada peningkatan pertumbuhan sebesar 25,76% pada benih ikan nila merah NIFI F1

KAJIAN ASPEK FISIKA, KIMIA, DAN BIOLOGI PERAIRAN SITU RAWABEBEK, KARAWANG, DALAM RANGKA PENGELOLAAN PERIKANAN BERBASIS BUDI DAYA

Penelitian tentang aspek-aspek fisika, kimia, dan biologi perairan bekas galian pasir telah dilakukan di Situ Rawabebek Kabupaten Karawang. Tujuan penelitian adalah untuk mendapatkan data dasar bagi penyusunan model pengelolaan perikanan di perairan bekas galian pasir berdasarkan prinsip perikanan berbasis budi daya (culture-based fisheries, CBF). Hasil pengamatan menunjukkan bahwa fluktuasi air di Situ Rawabebek mencapai hingga 1,90 m dan sangat dipengaruhi oleh ketinggian air Sungai Citarum. Nilai semua parameter kualitas air berada dalam kisaran yang layak untuk mendukung kehidupan ikan sementara kadar logam berat berada dalam ambang aman untuk kehidupan organisme akuatik termasuk ikan dan kesehatan manusia. Indeks keragaman plankton (Indeks Shanon-Wiener) pada setiap stasiun dan musim pengamatan berkisar antara 3,95—4,52 yang berarti bahwa komunitas plankton di Situ Rawabebek stabil dan perairannya dalam kondisi belum tercemar. Jenis ikan yang teramati untuk mengetahui pola reproduksinya di Situ Rawabebek antara lain lalawak (Puntius bramoides), paray (Rasbora argyrotaenia), dan seren (Cyclocheilichthys apogon) dengan tingkat Indeks Kematangan Gonad (IKG) masing-masing 3,43%; 12,82%; dan 3,95%. Dari analisis terhadap kondisi fisika, kimia, dan biologinya disimpulkan bahwa perairan bekas galian pasir Situ Rawabebek cukup layak untuk pengembangan perikanan berbasis budi daya. A study on the physical, chemical, and biological aspects of the abandoned sand mining reservoir was conducted in Rawabebek Reservoir (Karawang Regency, West Java). This study aimed to develop a model of fisheries management in the reservoir based on the culture based fisheries (CBF) system. The study showed that the fluctuation of water level in the Rawabebek Reservoir was monitored up to 1.90 m and highly influenced by the water level of Citarum River. The average value of all water quality parameters and heavy metals were in the suitable range for aquatic organism, fish and human health. The diversity index of plankton (Shanon-Wiener Index) at each station and sampling time observed, were ranged between 3.95 to 4.52 implied that the plankton community in the Rawabebek Reservoir was in the stable condition with no water pollution. Three fish species were observed for reproduction pattern in the Rawabebek Reservoir namely lalawak (Puntius bramoides), paray (Rasbora argyrotaenia), and seren (Cyclocheilichthys apogon) with the Gonadosomatic Index (GSI) were 3.43%, 12.82%, and 3.95%, respectively. Due to those physical, chemical and biological aspects, it was concluded that Rawabebek Reservoir was suitable for culture based fisheries (CBF) management system

CARBON TO NITROGEN RATIO AND NITROGENOUS WASTE ACCUMULATION IN THE INTENSIVE CATFISH (Clarias gariepinus) CULTURE

This experiment was carried out to determine the optimum C/N ratio for heterotrophic bacteria (biofloc) growth in order to control nitrogenous waste accumulation in the catfish (Clarias gariepinus) culture. Twenty fish with an initial individual size of about 50 g were stocked in fiberglass tanks which were filled with 200 L of water. Fish were fed with commercial floating fish feed with a protein level of 31%-33% (manufacturer label). The daily feeding rate was 2.5% of the fish biomass. The inoculation of commercial Bacillus sp. isolates was applied in the first day of the experiment after fish stocking in order to obtain a bacterial density in water of 106 cfu/L. Molases was suplemented daily to the tanks to adjust C/N ratio in water. Four C/N ratios, i.e. 0, 7, 14, and 21, were applied as treatments in this experiment. The results showed that molasses suplementation up to C/N ratio 14 to 21 were able to support the growth of heterotrophic bacteria and to inhibit the accumulation of total ammonia nitrogen (TAN) and nitrite in water therefore increase water quality for better growth of cultured catfish

OPTIMASI PADAT PENEBARAN LARVA IKAN PATIN SIAM (Pangasius hypophthalmus) PADA PEMELIHARAAN SISTEM INTENSIF

The goal of this activity was to improve the productivity of Siamese catfish (Pangasius hypophthalmus) backyard hatchery. The research was conducted to identify the optimum density of larvae in the intensive rearing system. Two days post hatching larvae of P. hypophthalmus reared in 18 fiberglass containers size 40x30x30 cm3. The treatment used was 50, 100 and 150 fishes/litre in 6 replicates. A water recirculation system was used in this study and a hi-blower aeration system for oxigen supplay was added in it. The result showed that the density of larvae was not significant difference (P0,05) for body weight at day-30, i.e. 0.47; 0.34 and 0.25 g/fishes for 50, 100 and 150 fishes/l, respectively

OPTIMASI PEMBERIAN PAKAN BUATAN PADA PENDEDERAN IKAN PATIN (Pangasionodon hypohpthalmus) DI KOLAM YANG DIPUPUK

This research aimed to know the optimum formulated feeding patin (Pangasionodon hypohpthalmus) in the fingerling rearing in the fertilized pond. The fish seed were stocked in the fifteen cages of 3x2x1.25 m that were installed in the 50 m2 pond. Each cage was stocked with 600 fish with an average initial weight of 0.37 g and average body length of 2-3 cm. The treatments applied in this research were (A) without formulated feed, (B) 5% of biomass of formulated feed, (C) 10% of biomass of formulated feed, (D) 15% of biomass of formulated feed and (E) 20% of biomass of formulated feed. The protein level of the formulated feed was around 40%. The observations focused on the survival rates of fish, feed conversion ratios, body weight and length. The results showed that there were significant differences among fish treatments on the survival rates, feed conversion, weight and length growth (P<0,05). The survival rates of fish of the treatment A, B, C, D and E were 78.10%, 84.39%, 83.78%, 90.83% and 90.33%, respectively. The feed conversion of the feed given treatments i.e. B, C, D and E were 0.35, 0.62, 0.89 and 1.15, respectively. The weight growth during observation period (6 weeks) were 5.63 g, 15.29 g, 23.37 g, 39.17 g and 42.13 g for the treatments A, B, C, D and E, respectively, while the length increment for those treatments were 4.63 cm, 7.81 cm, 8.91 cm 1.5 cm and 11.05 cm, respectively. The water quality parameters were in the suitable range for fish growth

PEMACUAN PERTUMBUHAN IKAN NILA (oreochromis niloticus) MELALUI PENERAPAN SISTEM BIOFILTER DAN AERASI DI KOLAM TADAH HUJAN

Kualitas air kolam tadah hujan yang cepat memburuk mengakibatkan penurunan lajupertumbuhan ikan yang dipelihara. Untuk mengatasi hal tersebut, penelitian pemacuanpertumbuhan ikan nila di kolam tadah hujan telah dilakeanakan di Balai Penelitian Perikanan Air Tawar, Sukamandi

Effect of Different Feed Restrictions on Growth, Biometric, and Hematological Response of Juvenile Red Tilapia (Oreochromis spp)

Highlight Research • There has been a significant decrease in growth, condition factors, hepatosomatic index along viscerosomatic index with the length of time for feed restriction, although fasting for up to 28 days did not cause fish mortality • Hematological parameters such as RBCs, WBCs, hematocrit, and hemoglobin decreased significantly, but after re-feeding increased significantly in consecutive times • The blood glucose levels decreased during feed restriction and gradually increased after re-feeding • Feed restriction ï¬sh gained weight continuously during re-feeding, but no displaying compensatory growth • The decrease in hematological parameters did not indicate stress levels in fish, but reflected a lack of nutrition condition   Abstract The management of red tilapia culture can be improved through restriction of feed. This study aimed to determine the impact of feed restriction time and re-feeding on the growth and hematological performance of juvenile red tilapia. This study used an experimental method with a completely randomized design consisting of five treatments with four replications, namely the fish were given food for 28 days (A), 7 days of feed restriction followed by 21 days of refeeding (B), 14 days of feed restriction followed by 14 days of refeeding (C), 21 days of feed restriction followed by 7 days of refeeding (D) and 28 days of feed restriction (E). The parameters observed were growth, biometry, and hematological values. The results showed that during the feed restriction period there was a significant decrease in growth, condition factors, hepatosomatic index along with viscerosomatic index with the length of time for feed restriction, although fasting for up to 28 days did not cause fish mortality. Hematological parameters such as RBCs, WBCs, hematocrit, and hemoglobin decreased significantly, but after re-feeding, they increased significantly in consecutive times. As for the blood glucose levels decreased during feed restriction and gradually increased after re-feeding. This study stated that feed restriction ï¬sh gained weight continuously during re-feeding, but no displaying compensatory growth. The results suggested that the decrease in hematological parameters did not indicate stress levels in fish, but reflected a lack of nutrition condition

Evaluation of Growth Performance and Improving Genetic Gain of Blue Tilapia (<I>Oreochromis aureus</I>) Fourth-generation (F-4) at Brackish Water Pond

Highlight Reseacrh • The study showed that the selected F-4 blue tilapia had a better growth pattern than the control (non-selection) F-4 blue tilapia • The difference in performance between the two populations of blue tilapia is an illustration of the genetic improvement that is passed on from parents to offspring as a result of the selective breeding • The realized heritability value of the weight character of F-4 blue tilapia in the high category • There was an increase in growth in the F-4 blue tilapia population with a positive response to selection   Abstract Breeding program in order to increase genetic improvement in blue tilapia have not been widely carried out at brackish water ponds. This study aimed to evaluate the increase in growth and genetic gain of F-4 blue tilapia from family selection in ponds with 25-30 gL-1 salinity. The parent used for the formation of F-4 is the selected parent F-3 and as a control using the non-selected parent F-3. Spawning was carried out in a full-sib mating design using the family selection method. The ratio of male and female broodstock is 1: 2. Spawning and nursery activities of F-4 blue tilapia are carried out in freshwater. The enlargement test was carried out in the net cage 5m x2.5m x1 m which was installed in the ponds with a salinity of 25-35 g l-1 for 120 days, at a stocking density of 10 fish m-2. At the end of maintenance, a selection process is carried out on the weight traits. Parameters observed included growth, survival, and genetic values. The results showed that the growth and survival in the F-4 blue tilapia population, male and female selected populations, had a higher value than in the non-selected population. The realized heritability value of the population growth character of the F-4 blue fish is in the high category. The difference in the average weight of the selected blue tilapia and the control was equivalent to an increase in genetic value added by 15.06% (male population) and 17.92% (female population)