• ETRI Journal
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• v.28 no.6
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• pp.697-708
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• 2006

Various adaptive mesh refinement techniques are often employed in numerical simulations for increasing spatial and temporal resolution beyond the limits imposed by available CPU time and memory space. Recently, an octree-based adaptive mesh structure was successfully used in fluid animation to place more grid cells efficiently in visually interesting regions of fluids. In an attempt to optimize the use of computational resources further in fluid animation, this paper extends this adaptive technique by modifying the mesh refinement scheme so that the camera's viewing properties are dynamically exploited during the simulation. Based on a simple adaptive mesh structure, we show that the new meshing strategy can save a substantial amount of computation time and memory space by using a view-dependent adaptive approach. The experimental results reveal that the proposed technique provides a good compromise between the computational effort and the simulation's fidelity, and may be used quite effectively in 3D animation production.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.3
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• pp.21-27
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• 2002

In this paper, a simple test rig of high-speed crash for the front members of vehicles was developed for the improvement of crashworthiness of vehicle's side rail. The cart hanging the specimen is accelerated up to 35 mph by the traction wire and by the force of freely dropping weight and 1:3 accelerating pulleys. The cart with shock absorbers travels on the rail roads, so it does not transfer any additional vibration to the specimen. In order to measure the energy absorbed by the specimen when it collapse to the wall and during it deform, the two strain gage type load cells are used at the wall place. The test rig rated good to test the specimen like a side rail of vehicle as developing the vehicle's structures in the early design stage.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.56-56
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• 2003

The reactivity and toxicity of arsenic compounds depend on the their oxidative states. Exposure to arsenic causes many human health effects, including cardiovascular, hepatic and renal disease, in addition to cancer in kidney, liver, lung, urinary bladder and skin. The cytotoxic effects of arsenite on normal hepatocyte, which most of its biotranfomation takes place. (omitted)

• Proceedings of the IEEK Conference
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• 2001.06a
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• pp.285-288
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• 2001

In this paper, we propose strategies that eliminating packet loss and minimize delay time during handoff under wireless LAN environments. As a mobile host moves between cells, a handoff takes place. A few handoff protocol have been proposed to eliminate the packet loss, but they have a heavy overhead. So, We proposed handoff protocol using the next-cell prediction scheme that send not to current BS but to mobile host and next BS, therefore next BS buffered packet send mobile host after handoff. We also present simulation results for our simulation using the Network Simulator (ns2). The simulations show that our handoff scheme is no packet loss.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.6
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• pp.391-397
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• 2015

Nonvolatile memories in memory hierarchy have been investigated to reduce its energy consumption because nonvolatile memories consume zero leakage power in memory cells. One of the difficulties is, however, that the endurance of most nonvolatile memory technologies is much shorter than the conventional SRAM and DRAM technology. This has limited its usage to only the low levels of a memory hierarchy, e.g., disks, that is far from the CPU. In this paper, we study the use of a new type of nonvolatile memories - the Phase Change Memory (PCM) with a DRAM buffer system as the main memory. Our design reduced the total energy of a DRAM main memory of the same capacity by 80%. These results indicate that it is feasible to use PCM technology in place of DRAM in the main memory for better energy efficiency.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.409-415
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• 2007

An eight years old female barbary sheep (Ammotragus lervia), which bred at the Gwangju Uchi Park Zoo had shown anorexia, depression, respiratory problem for several weeks after parturition. In necropsy, extensive necrotizing pneumonia was found with severe immunocytes infiltration in the alveolar spaces and bronchioles. Pulmonary pleura were thickened with fibrin and inflammatory cells. Bacteria were isolated from lung and identified as Streptococcus equi subsp. zooepidemicus (SEZ) by biochemical tests and PCR on sodA and gusA genes, though seel gene was not detected. Isolation of zoonotic SEZ in public place such as a zoo should be emphasized for the public health mangagement.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.75-85
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• 1991

Changes in the activities of isocitrate dehydrogenase (IDH) and glutamate dehydrogenase (GDH) and changes in free amino acids in the cytoplasm of Saccharomyces cerevisiae have been studied under heat shock condition. Heat shock conditions led to a significant decrease of NAD-IDH and NAD-GDH, It was shown appeared that the meaningful patterns of increase of NADP-IDH and NADP-GDH. It suggested that heat shock in yeast leads to a splitting of the TCA cycle and that glutamate synthesis takes place through the coupling of the NADP-linked isocirate and glutamate dehydrogenase. It was shown that about 14% of total free amino acids of yeast cells was decreased by heat shock. Especially heat shock condition resulted in the marked decreases of serine family amino acids such as serine, glycine and cysteine, and in the considerable increases of the rates of methionine, alanine, glutamin.

• Archives of Pharmacal Research
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• v.28 no.8
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• pp.963-969
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• 2005

Many reports have stated that some of the pathogenic bacteria can obtain iron from ferroproteins, such as cytochrome C, ferritin, hemin, hemoglobin, and myoglobin. These reports prompted us to determine if an opportunistic pathogenic fungus, Candida albicans, can utilize ferroproteins to circumvent the iron-regulatory effect of transferrin. The following assays were carried out to measure in vitro growth stimulation by the ferroproteins: as an initial step, C. albicans was cultured in iron-free (pretreated with apotransferrin for 24h) culture medium. Once Candida albicans yeast cell growth reached stasis from iron starvation, individual ferroproteins were added to the culture media. Results showed that hemin, hemoglobin, and myoglobin supported a partial growth recovery. Additional studies with haptoglobin, a serum protein that interacts with the globin moiety of certain ferroproteins, established that C. albicans could obtain iron from the haptoglobin-ferroprotein complexes. These data indicate that the heme part of the ferroproteins is the source of iron. This implies that heme oxygenase, CaHMX1 might be involved in bringing about dissociation of heme-containing protein for iron-acquisition. In addition, anticandidal activity of transferrin takes place not only by the process of iron regulation, but also by direct interaction with the yeast cells.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.38-47
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• 2003

Relationships between accumulations of endocrine disruptors and abnormalities in the reproductive organs in the adult male striped field mice, Apodemus agrarius, were reviewed. High levels of phenolic compounds were detected in the mice collected at an agricultural village in Gaduck island and at a place having a sewage problem in Samdong-myeon, Namhae. High levels of organo tin compounds were found in the mice collected at Jiri Mt. a tourist resort. Considerably high levels of phenolic or organo tin compounds were detected in mice with shrunken reproductive organs accounting for 14∼42% of the mice examined in each area, which suggests that the abnormality of reproductive organs may be induced by the endocrine disruptors. This hypothesis is strongly supported by histological observations of shrunken reproductive organs, such as necrosis of testicular germ and epithelial cells. This was found not only in the mice with shrunken reproductive organs but also in the mice with enlarged reproductive organs, both had accumulated high levels of endocrine disruptors in general.

• Mycobiology
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• v.50 no.3
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• pp.172-180
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• 2022

The new genus and species, Jejulea byssolomoides, is described from Jeju Island, Korea. This lichen is characterized by saxicolous, crustose, pale greenish-gray, partly finely filamentous, matt, smooth thallus, prominent convex brown to dark brown ascomata with a concolorous margin constricted at the dark brown base, 300-800 ㎛ diameter, 200-250 ㎛ high, without a distinct proper margin, adhering to the substratum ending in a minute byssoid white external part of cylindrical cells, fusiform 3-5 septate ascospores (17-23 × 4-5 ㎛). Phylogenetic analyses using ITS and mtSSU sequences place Jejulea in the Pilocarpaceae (Lecanorales). The new taxon is closely related to Byssoloma, a cosmopolitan group of foliicolous lichens, which is most diverse in the tropics. Like Byssoloma, Jejulea also forms a byssoid apothecial margin.