• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.22-27
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• 2002

The composting practice has been recognized as the most popular way of controlling food waste and many attempt have been made in the field to establish more efficient and economical process. Some of the efforts are mixing cured compost with sawdust as alternative bulking agent, seeding commercially produced microorganism and/or combination of above. However, verification of such efforts is often restricted because of either the lack of engineering consideration on the limitation of composting facility scales. In this study, the effect of mixing materials in food waste composting was investigated by controlling the combination and the mixing ratio of them. When the cured compost was mixed with saw dust. the decomposition of organic material was proven to be more active by observing the compost temperature, the oxygen (O$_2$) consumption, and the cumulative carbon dioxide ($CO_2$) profile. However, the quantity of compost mix-ing seemed not to influence the reaction as long as the minimum required amount was mixed. The feeding of com-mercially produced microorganism had a tendency to prolong the thermophilic stage, which helped to increase the decomposition but it resulted in composting period. Regardless of the composting condition, bacteria and actinomycetes increased in population as the reaction approached to the end. The population of bacteria and actinomycetes were rel-atively higher than those of fungi and yeast throughout the reaction.

• Journal of the Korean Ceramic Society
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• v.41 no.11
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• pp.842-850
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• 2004

We have investigated on the preparation of BaTiO$_3$ powder at the system of BaO$_2$-TiO$_2$-Reduction ag.-PSCA by SHS. C and Mg were used as reduction agent, and NaCl was used as PSCA (Particle Size Control Agent). The effects of the various reduction agent and its concentration, particle size control agent, reaction mixture mass on the product in the preparation of BaTiO$_3$ powder at the optimum system by SHS were investigated. The optimum conditions for reaction system and composition were BaO$_2$+TiO$_2$+0.11 Mg +0.2C+0.75NaCl in the As atmosphere. NaCl as PSCA showed the effect of controlling the particle size of product as well as the combustion temperature. The particle size of BaTiO$_3$ synthesized at the optimum condition was about 0.5 ${\mu}{\textrm}{m}$. And as the mixture mass for the reaction was increased, the more stable combustion wave appeared. We have conducted the sintering experiment at the temperature of 130$0^{\circ}C$, the time of 2 h and the atmosphere of air to measure the dielectric properties of BaTiO$_3$ synthesised in this work, and the sample sintered in this condition showed 2,290 of dielectric constant at 10$0^{\circ}C$ and 13,890 at curie point (129$^{\circ}C$).

• Smart Media Journal
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• v.13 no.2
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• pp.32-43
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• 2024

Game agents which are behavioral agent for game playing are a crucial component of game satisfaction. However it takes a lot of time and effort to create game agents for various game levels, environments, and players. In addition, when the game environment changes such as adding contents or updating characters, new game agents need to be developed and the development difficulty gradually increases. And it is important to have a game agent that can be customized for different levels of players. This is because a game agent that can play games of various levels is more useful and can increase the satisfaction of more players than a high-level game agent. In this paper, we propose a method for learning and controlling the level of play of game agents that can be rapidly developed and fine-tuned for various game environments and changes. At this time, reinforcement learning applies a policy-based distributed reinforcement learning method IMPALA for flexible processing and fast learning of various behavioral structures. Once reinforcement learning is complete, we choose actions by sampling based on Softmax-Temperature method. From this result, we show that the game agent's play level decreases as the Temperature value increases. This shows that it is possible to easily control the play level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.1
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• pp.34-40
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• 2009

In fresh water fish hatcheries and farms, Saprolegniales often cause serious mortality to the fish and their eggs. Malachite green is an effective antifungal agent, but is carcinogenic to fish and humans. Alternative antifungal agents are needed. Presently, we tested various concentrations of MBT-01108 (Opuntia ficus-indica extracts) alone and in combination with bronopol, formalin and sodium chloride (MBT-01108 mixture) on in vitro mycelial growth and in vivo remediation of adult eel, Anguilla japonica, infected with Saprolegnia sp. and fertilized eggs of chum salmon, Oncorhynchus keta, to evaluate the compounds' antifungal efficacy on eyed-egg and hatching rates. MBT-Oll08 mixtures incorporating bronopol and formalin at respective concentrations of 50 and 30 parts per million (ppm), and 100 and 20 ppm were most effective in controlling Saprolegnia in vitro and in vivo (P<0.05). Repeated daily exposures to 50 ppm and 100 ppm MBT-01108 were more effective than exposure every 2-3 days post-fertilization for the inhibition of Saprolegnia infection of rainbow trout, Oncorhynchus mykiss eggs as compared with control (0 ppm).

• Journal of fish pathology
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• v.6 no.2
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• pp.191-195
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• 1993

With the rapid progress in seed production techniques, aquaculture production of economically important species of marine fish has been accelerated in Japan. Howecer, mass mortalities due to viral infections as well as other microbial infections have often occurred during the seed production and grow-out stages. Among these diseases, four viral diseases have been known in cultured Japanese flounder (Paralichthys olivaceus) since around 1980. In this paper, viral diseases of cultured flounder in Japan are briefly reviewed, with special attention to two viral diseases. viral epidermal hyperplasia and rhabdovirus infection which are relatively important because of their frequent occurrence. Viral epidermal hyperplasia is characterized by fin opacity and associated with high mortality in larval flounder Electron microscopy of affected epidermal cells and transmission experiments with tissue filtrates demonstrated that the disease was caused by a herpesvirus but the agent has not been isolated in fish cell lines. On the other hand, rhabdovires infection occurrs in juvenile and production size fish with hemorrhage in the skeltal muscle and fins, congestion of the gonads, and ascites. A rhabdovirys was isolated in RTG-2 cells from the diseased flounder as a causative agent, which was designated hirame rhabdovirus (HRV) or Rahbdovirus olivaceus. HRV is serologically distinguishable from other known fish rhabdoviruses. Intensive researches on these viral diseases started in 1980th. but properties of the causative agents and infection mechanisms have not been fully investigated. This results in difficulty in controlling these diseases.

• Ocean and Polar Research
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• v.30 no.4
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• pp.467-472
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• 2008

Antarctic krill has a strong proteolytic enzyme system, which comes from a combination of several proteases. This powerful activity can be easily detected by krill's superior post mortem autolysis. Mammalian skin consists of epidermis and dermal connective tissue, and functions as a barrier against threatening environments. A clot in a wound site of the skin should be removed for successful skin regeneration. Epithelial cells secrete proteases to dissolve the clot. In previous studies Antarctic krill proteases were purified and characterized. The proteolytic enzymes from Antarctic krill showed higher activity than mammalian enzymes. It has been suggested that these krill clean up the necrotic skin wound to induce a natural healing ability. The enzymes exhibited additional possibilities for several other biomedical applications, including dental plaque controlling agent and healing agent for corneal alkali burn. Considering that these versatile activities come from a mixture of several enzymes, discovering other proteolytic enzymes could be another feasible way to enhance the activity if they can be used together with krill enzymes. Molecular cloning of the krill proteases should be carried out to study and develop the applications. This review introduces possible roles of the unique Antarctic krill proteases, with basic information and suggestion for the development of an application to skin regeneration.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.332-335
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• 2009

Rhizo-bacteria were isolated from organic-farming soils to select antagonistic agent for controlling citrus melanose disease. Among several antagonistic bacteria, KB-401 effectively inhibited mycelial growth of several plant fungal pathogens, including the pathogen of citrus melanose, Diaporthe citri. KB-401 also inhibited spore germination of the fungal pathogen. The tip of germ tube was swollen when conidia of D. citri were co-culture with KB-401 in PD broth amended 1% glucose. KB-401 was identified as Bacillus subtilis through the investigation for physiological characters and the analysis of nucleotide sequences of 16S rDNA.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.501-502
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• 2009

This paper presents a strengthening technique of weakened telegraph pole using an inflating agent to adjust chemical pre-stressing. The strengthening technique increases only resisting capacity and ductility of telegraph but also limited quantity and application ability of FRP. The chemical pre-stressing and the resisting capacity are investigated experimentally. From the results, it is confirmed that it is possible to control the degree of applied pre-stressing by controlling the amount of inflating agent. In addition, the pre-stressing can increase resisting capacity up to three times compared with no pre-stressing.

• Journal of the Korea Computer Graphics Society
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• v.3 no.1
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• pp.37-47
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• 1997

This paper presents the algorithms for generating ambient traffic in driving simulation. Each ambient car is modeled as an autonomous agent that obeys the traffic rules by sensing the traffic lights, road signs, lanes, and other cars around. The algorithm is localized to the area where the car driven by the participant is currently located. Therefore the complexity of the algorithm does not depend on the size of the road network, allowing a huge environment to be simulated with no extra overhead. To avoid monotony, we produce artificial fluctuations in the behavior by employing various forms of probability distribution functions. The resulting behavior of the ambient cars is quite realistic. Experiments indicate that it is hard to tell whether an ambient car is computer-controlled or human-controlled.

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.263-268
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• 2009

Superporous Hydrogels (SPHs) have been extensively investigated for various biomedical applications due to their fast swelling and superabsorbent properties. In this study, glycol chitosan that is one of most abundant natural polymers was used as a cross-linking agent instead of bisacrylamide (BIS), which is a broadly used crosslinking agent for preparation of SPHs. Glycol chitosan was modified to have reactive vinyl groups by chemical conjugation with glycidyl methacrylate (GMA). The vinyl group-containing glycol chitosan (GC-GMA) was characterized by FT-IR and $^1H$-NMR measurements. SPHs have been prepared in various synthetic conditions to establish the optimum synthetic process for making superporous structure, where the inner pores are interconnected to each other to form a open channel structure. Various SPHs with different GC-GMA contents have been successfully prepared and have been observed to show faster swelling properties than other conventional SPHs. From the study on the swelling behavior of SPHs, the GC-GMA content is considered to be an important factor for controlling their swelling properties.