• Journal of Navigation and Port Research
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• v.34 no.10
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• pp.793-797
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• 2010

The depleting fishes resource and water pollution in coast has a decisive effect on the fish farm and fisheries. For solving these problems the fish farms are moving to the offshore. The fish farms in offshore have to design the strong mechanism as compared with cost's fish farm, and operate by the remote feeding system and monitoring system for safety and management.. This paper describes a remote feeding system for fish farms in offshore. The amount of feed is depending on temperature and fish weight. The fish farm temperature is changed extremely in offshore than on land side. This paper described that the feed amount is calculated automatically according to temperature and fish weight, and the remote feed system. The performance of remote feed system is tested with model.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1527-1532
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• 2007

Lysine produced during microbial fermentation is usually recovered by an ion-exchange process, in which lysine is first converted to the cationic form (by lowering the pH to less than 2.0 with sulfuric acid) and then fed to a cationexchange column containing an exchanger that has a sulfone group with a weak counterion such as NH;. Ammonia water with a pH above 11 is then supplied to the column to displace the purified lysine from the column and allow its recovery. To enhance the adsorption capacity and for a possible reduction in chemical consumption, monovalent lysine fed at pH 4 was investigated in comparison with conventional divalent lysine fed at pH 1.5. The adsorption capacity increased by more than 70% on a mass basis using pH 4 feeding compared with pH 1.5 feeding. Lysine adsorbed at pH 4 started to elute earlier than that adsorbed at pH 1.5 when ammonia water was used as the eluant solution, and the extent of early elution became more notable at lower concentrations of ammonia. Moreover, the elution of monovalent lysine fed at pH 4 displayed a stiffer front boundary and higher peak concentration. However, when the ammonium concentration was greater than 2.0 N, complete saturation of the bed was delayed during adsorption and the percent recovery yield from elution was lowered., both drawbacks that were considered inevitable features originating from the increased adsorption of monovalent lysine.

• Journal of Aquaculture
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• v.10 no.2
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• pp.97-103
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• 1997

Larval growth of the oyster, Crassostrea nippona, was investigated at the different conditions such as water volume, depth of culture vessel and initiative feeding time at $23^{\circ}C$. As a result, morphological changes were occurred during the early larval growth. That is, shell length was higher than shell height at the time of D-shaped larvae. Later, the length became equal to the hight when their shell length reached $127\mum$and then shell height increased rapidly. Some of pediveliger larvae with the size of $360\mum\;in\;shell\;length\;and\;385\mum$ in shell height began to temporarily settle on the substrate after 18 days. The result also indicated that the depth of culture vessel turned out to be an important factor rather than water volume for the larval growth. The fist feeding time of oyster larvae appeared to be the first day after fertilization.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.169-180
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• 2023

Oreochromis niloticus is the most ecologically and economically important fish in tropical and sub-tropical aquatic systems. Recently, due to sever anthropogenic stressors, hydrological variations and infestations of invasive alien species in Ethiopian water bodies, fish community structure and ecosystem of Lake Tana is changing alarmingly. So far, there is paucity of information on the morphometric relations and diet composition of O. niloticus in Lake Tana, gulf of Gorgora. A total of 309 fish samples were collected and their total length (TL), standard length (SL) and total weight (TW) were measured to determine morphometric relations; and gut contents were examined to identify most important food item in the diet of the fish. Results indicated that, the relation between TL and SL was significant (p < 0.001) and linear (SL = 0.942TL-2.41) while the relation between TL and TW was curvilinear (TW = 0.014 TL^2.8) indicating allometric growth. Among the total guts scrutinized, 53 (17.3%) of them were empty and the remaining 256 (82.7%) were non-empty. Phytoplankton constituted the largest bulk and occurred in 77% of the guts examined and volumetrically accounted 44.3%. Detritus and zooplankton had an intermediate importance by occurring 60.2% and 63.3% of all guts scrutinized and constituted about 25.6% and 15.5% of the total volume respectively. Contributions of macrophytes, insects, nematodes and unidentified food items were relatively low in their importance. Ontogenetic dietary shift was observed in the diet indicating an omnivorous feeding habit of the adult fish.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.313-317
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• 2005

The facility improvement for hot firing test of combustion chamber having thrust of 30-tonf class and chamber pressure of 60bara were performed at ReTF in KARI. The KSR-III main engine having combustion pressure of 13bara and thrust of 12.5tonf had been successfully tested in this facility. To increase the capability of the facility, the feeding and the trust measurement system have been modified. The modification of the feeding system plays also a role of ensuring the stability of propellant supply and two step ignition sequence of combustion chamber. The one-axis thrust measurement system of up to 60tons has been newly manufactured and installed in test stand and the water/kerosene supply lines with high pressure vessel of $4m^3$ and gas nitrogen vessel of $10m^3$ have been designed for regenerative cooling system. The results of cold flow test show that this facility has been successfully improved to satisfy the requirement for hot firing test of high performance combustor.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.266-270
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• 1985

In order to obtain the fishing possibility by acoustic, the two fishes, Lateolabrax japonicus, Mugil cephalus, were bred in a water tank. The feeding sounds from the fishes and the artificial sounds were recorded by a hydrophone and then the frequency and the sound pressure level of the sounds recorded were analyzed by the digital frequency analyzer. These sounds were edited in two manners of which one is emitted for 10 seconds and paused for 10 seconds continuously and the other is emitted for 20 seconds and paused for 20 seconds also. These edited sounds were emitted again into the tank and the respose of fisher were observed. Lateolebrax japonicus showed a positive response and Mugil cephalus responsed a little positively to the emitted feeding sound, The fishes seemed to show a positive response only in emitting a moderate pressure level of feeding sound. Lateolabrax japonicus and Mugil cephalus showed negative response to the emitted artificial sound. It was most effective to increase the sound pressure level that the fishes went away from the sound source to the emitted artificial sound.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.720-728
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• 2000

The different products of neem (Azadirachta indica) are utilized for variety of purposes in industry, health and animal agriculture in the Indian subcontinent. The cake from seeds after oil extraction is a good source of nutrients (CP: 35-38%; EE: 4.5-5.5%; CF: 12-15%; Ca: 0.75%; P: 0.45% on DM), and in particular, the one out of its kernel is proteinaceous and is relatively balanced in its amino acid and mineral profile. But the cake is toxic and bitter to taste owing to triterpenoids (nimbin, salannin, azadirachtin), which restricts its safe inclusion in livestock diet. Several feeding trials with raw cake have revealed poor palatability and adverse performance among different categories of livestock and poultry. Internal organ changes included histological alteration in intestine, liver, kidney and distruption of spermatogenesis and ovarian activity. Ruminants appears to tolerate reasonably higher levels of the cake and to a limited low levels of dietary inclusion also proved to be tolerable in monogastric farm animals. Debitterization through solvent (hexane, ether) extraction, water washing, alkali (NaOH, 1.5, 2.5 or 3%, wt/wt) soaking and urea (1.5 or 3%, wt/wt) - ammoniation have been tried with appreciable success in improving the palatability and nutritive value of the cake. For enhanced utilization, decortication of neem seeds is to be done effectively at industrial level with maximum oil recovery. The resultant proteinaceous kernel by-product could be a cheaper unconventional protein supplement after suitable processing.

• Korean Journal of Environmental Biology
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• v.26 no.3
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• pp.203-213
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• 2008

Benthic macro invertebrate communities were collected at six different sampling sites in the Musucheon stream in Korea from July 2006 to July 2007, and ecological exergy values were calculated based on five different functional feeding groups (collector-gatherer, collector-filterer, predator, scrapper, and shredder) of benthic macro invertebrates. Each sampling site was categorized to three stream types (perennial, intermittent and drought) based on the water flow condition. Exergy values were low at all study sites right after a heavy rain and relatively higher in the perennial stream type than in the intermittent or the drought stream type. Self-Organizing Map (SOM), unsupervised artificial neural network, was implemented to pattern spatial and temporal dynamics of ecological exergy of the study sites. SOM classified samples into four clusters. The classification reflected the effects of floods and droughts on benthic macroinvertebrate communities, and was mainly related with the stream types of the sampling sites. Exergy values of each functional feeding group also responded differently according to the different stream types. Finally, the results showed that exergy is an effective ecological indicator, and patterning changes of exergy using SOM is an effective way to evaluate target ecosystems.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.2
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• pp.169-175
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• 2016

The feeding habits of yellowfin goby (Acanthogobius flavimanus) were studied based on the examination of stomach contents of 171 specimens collected from September 2013 to August 2014 in the tidal flat of Sangnae-ri, Suncheon, Korea. The size of A. flavimanus ranged from 10.6 to 18.3 cm in standard length (SL). A. flavimanus mainly consumed amphipods (especially Corophium sp.). Its diet also included shrimps, crabs, fishes and polychaetes. Ontogenetic changes in diet composition of A. flavimanus were evident. The portion of amphipods and polychaetes was inversely proprotional to the increase in fish size whereas it was directly proportional to the increase in the consumption of shrimps and crabs increased.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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• pp.643-649
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• 2002

Availability of feeds and fodder and amount of their intake by large ruminants in eight different agro-ecological zones (AEZ) of Bangladesh were recorded over a year. Roughages such as straw, naturally grown green grass, water hyacinth, tree leaves, legumes and sugarcane tops were the major feedstuffs fed to the large ruminants. Amount of intake of these ingredients differed (p<0.01) across AEZ studied, but did not differ across seasons or farmers' categories (p>0.05) except for green grasses (p<0.01). Byproduct concentrates offered to animals in the studied areas were rice bran, wheat bran and different oil cakes. The amount of intake of concentrates by the animals also differed (p<0.01) across AEZs, but did not differ across seasons or farmers' categories (p>0.05), except for rice bran and wheat bran which differed between season and farm category, and season respectively (p<0.01). The large standard errors of mean indicate that there are wide variations in intake of roughages and concentrates across AEZ's, seasons and farmers' categories and even across days. This further indicates that the feeding practices of large ruminants are largely heterogeneous. In addition to feeding roughage and concentrates, the animals were allowed to graze for six hours a day. Grazing hours also differed (p<0.01) across AEZ, but not by farmers' categories or seasons.