• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.5
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• pp.169-177
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• 2011

In this study, an impact resistance of concrete segmented composites adopted shell's structures which have the excellent impact resistance was assessed. In order to enhance the performances of concrete segmented composite, the bond strength of mortar between the concrete blocks should be improved. Hence, in this study polymer mortars were applied to increase the bond strength of mortar. From the results of bond tests, the 15% latex mortar was selected and static and low-velocity impact tests were carried out for the specimens applied the plain and latex mortar. The concrete segmented composites, of which the bond strength of mortar was enhanced, showed improved low-velocity impact resistances. A Nonlinear finite element analysis using the discrete crack model showed similar energy dissipating capacities to the impact test's results. Consequently, by improving the analysis models for segmented composites, the impact resistances for manifold variables can be predicted and assessed.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.13-14
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• 2009

Segmented composite is known that resists at static and impact load well. In this study, segmented composite was evaluated by static and impact load test. Additionally, finite element analysis method was employed and optimal mix of mortar was developed. Therefore, impact resistance shows aspect that is influenced by interaction of interface and layout of segmented blocks.

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.129.1-129.1
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• 2009

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.33-36
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• 2008

It is generally known that a shell in the form of layered structures stacked up thin elements by organic adhesives has high resistance capacity against static and impact loading. The complex materials such as these diversified layered structures are more reliable and efficient to the impact loading than the single material. In this study, the segmented composites in the shape of a beam were made, using mortar and concrete block and tested under static and impact loading in order to develop the complex materials in the form of layered structures as the segmented composites to resist impact loading. And it compared to the normal concrete beams having the same compressive strength to evaluate the differences in their performance and failure modes.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.745-748
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• 2008

The past structures were just required bearing capacity to service load, serviceability, and resistance to corrosion. However this point of view has changed after 9.11 terrorism, capacities which can bear impact loading by explosion, and heat by fire happening at the same time, become to be important as a basic condition. The blast resistance capacity of structures is very important part against all over the world is intimidated by terrorism everyday in current point of time. The target of this research is a development of segmented composites and layered structures with high blast resistance using cementitious composites, concrete and FRP composites, which has high tensile strength and ductility, to apply in not only existing facilities but also new ones. Through the improvement of blast resistance, casualties and economic loss can be minimized, and it is possible to diminish the structure collapse and delay the time of structure collapse by thermal effect, impact loading, dynamic loading and high strain.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.95-105
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• 2008

Purpose: To identify which is the best procedure in recycling autograft according to the resection & reconstruction type and recycling methods, and so when the recycling autograft is used in limb salvage surgery. Materials and Methods: We have treated fifty-eight patients (34 male, 24 female; age range 5 to 74 years, mean age 36.5 years), who had the malignant musculoskeletal tumors, with recycling autograft (47 patients with extracoporeal irradiation, 11 patients with pasteurization) from December 1995 to February 2006. The resection and reconstruction type was 3 cases with fragmentary, 8 intercalary, 23 rAPC (recycling-Autograft-Prosthesis composite), 18 osteoarticular, 5 total joint and 1 soft tissue (achilles tendon). The result was evaluated by the radiologic union at junctional site, the functional score by musculoskeletal tumor society score and complications according to the resection & reconstruction type and recycling methods. Results: The junctional union was obtained at 15.0 months in extracoporeal irradiation and 12.6 months in pasteurization. Also the mean radiologic union was shown at 6.0 months in fragmentary, 12.8 months in intercalary, 10 months in rAPC, 23.3 months in osteoarticular and 15.6 months in total joint. The functional score was 65.5% in fragmentary, 60.8% in intercalary, 62.8% in APC (except pelvis), 66.0% in osteoarticular and 66.6% in total joint. We have experienced 1 infection, 1 prutrusio acetabuli in pasteurization (18.1%) and other 22 complications (3 deep infections, 8 nonunions, 2 fractures, 2 epiphyseal problems, 5 joint instabilities, 2 local recurrence) in extracoporeal irradiation (46.8%). Also we have experienced 3 complications (3 nonunions) in intercalary (37.5%), 9 complications (4 nonunions, 1 deep infection, 1 periprosthetic fracture, 1 epiphyseal problem, 1 local recurrence, 1 protrusio acetabuli) in rAPC (50.0%), 6 complications (2 deep infections, 2 nonunions, 1 epiphyseal problem, 1 pathologic fracture) in osteoarticular (33.3%), 5 complications (5 joint instabilities) in total joint (100%) and 1 complication(1 local recurrence) in soft tissue (100%). Conclusion: In our experience, according to the resection & reconstruction type fragmentary and intercalary may have several advantages such as good radiologic and functional result and low rate of complication. And it seems that rAPC was available in case which have no sufficient residual bone stock. Also the pasteurization may have more advantages than that of the extracorporeal irradiation.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.160-168
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• 2003

Background: Confirm the stability of intervertebral disc sustaining each fused lumbar spine cases, comparing vertical compression, A-P shear force and rotational moment on intervertebral disc of instrumented lumbar spine with simple vertical compression load and follower load using finite element analysis. Materials and Methods: We analyze the stability of intervertebral disc L4-5 supporting fused lumbar spine segments. After performing finite element modelling about L1-L5 lumbar vertebral column and L1-L4 each fusion level pedicle screw system for fused lumbar spine fine element model. Intervertebral discs with complex structure and mechanical properties was modeled using spring element that compensate stiffness and tube-to-tube contact element was employed to give follower load. Performing geometrical non-linear analysis. Results: The differences of intervertebral disc L4-5 behavior under the follower compression load in comparision with vertical compression load are as follows. Conclusion: As a result of finite element interpretation of instrumented lumbar spine, the stability of L4-5 sustaining fused lumbar segment, the long level fused lumbar spine observed hing stability under follower load. This research method can be the basis tool of effects prediction for instrumentation, a invention of a more precious finite element interpretation model which consider the role of muscle around the spine is loaded.

• Journal of Korea Game Society
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• v.8 no.3
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• pp.43-50
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• 2008

UI design is growing in meaning and form itself through the development of hardware and contents. And it makes users accept its interface as a extension of the body and mind because of the substantial rapport of the user and contents with developing of device and graphic. In this study, we analyzed user interface in a view of digital storytelling by observing of its role within user and contents. Not only this, classifying and investigating story elements in the games for forming the theoretical basis of storytelling UI are enforced. For the case study of UI, we choose the game, Diablo, Half-Life, and Homeworld because the game is suitable for the application of node-type storytelling and effectively uses graphic and input unit. This analysis explains the interface has the contents data that divided or shared and it means the interface performs its part of story nodes, which are extracted from the story, and choice. And we analogized that the story elemental can be substituted and used practically for interface because the stories made through the thing that users and developers are in the space of coexistence by the interface. Storytelling UI will be a good way to make a most intriguing piece as a joyful spontaneous complex that use story node. It is worth by reason of making by user and discovering live inner story so that it can approach to the substance of the story.

• Development and Reproduction
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• v.6 no.2
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• pp.97-104
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• 2002

In most mammals, mature oocyte-cumulus complexer(OCCs) ovulate into the oviduct where fertilization by sperm takes place. However, the complex that fail to fertilize eventually undergoes degeneration while they reside in the oviduct. Yet there is no blown mechanism how both oocyte and cumulus cells degenerate. Using human follicular fluid (hFF), bovine oviductal tissue extract (BOX) and mouse OCC, the present study aimed to find how the oviduct influence the viability of the oocyte and cumulus cells in vitro. There was no difference of oocyte maturation rate between the control and BOX-treated groups. However, there was a significant difference in the survival of cumulus cells between two groups. Cumulus cells cultured in the presence of hFF alone underwent initially expansion and then they formed monolayer in the culture dish. Even after 72 hr, they proliferated well and showed fibroblast-like morphology. Cumulus cells cultured in the presence of both hFF and BOX also expanded after 24 hr, however, after 72 hr culture, they eventually detached and degenerated. Cumulus cells cultured in the BOX alone gave a similar drastic result. When the cumulus cells cultured in the presence of BOX were stained with DAPI, their nuclei showed partial condensation and fragmentation. After detailed analysis of these cells by TUNEL assay, many nuclei of them exhibited well stained spots indicating the signs of apoptosis. Based upon these observations, it is suggested that BOX might possess a factor that leads mouse cumulus cells to undergo apoptosis in vitro.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.63-68
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• 1996

Background: Interferon-$\gamma$ has various biologic effects, including antiviral effect, antitumor proliferative effect, activation of macrophage and B lymphocyte, and increased expression of major histocompatibility complex. Especially, antitumor proliferative effect of interferon-$\gamma$ has already been proved to be important in vivo as well as in vitro. And, clinical studies of interferon-$\gamma$ have been tried in lung cancer patients. However, the mechanism of antitumor effect of interferon-$\gamma$ has not yet been established despite of many hypotheses. "Necrosis" is a type of cell death which is well known to occur in the circumstances of severe stresses. In contrast, "apoptosis" is another type of cell death which occurs in such biological circumstances as embryonic development, regression of organs, and self-tolerance of lymphocytes. And, apoptosis is an active process of cell death in which cells are dying with fragmentations of their cytoplasms and nuclei. And, in the process of apoptosis the DNAs of cells are cleaved between nucleosomes by unidentified endonuclease and therefore DNAs of apoptotic cells result in a typical electrophoresis pattern known as DNA ladder pattern. Recently it has been suggested that cytotoxic effect of interferon-$\gamma$ occurs via apoptosis. To elucidate the mechanism of antitumor cytotoxic effect of interferon-$\gamma$, we microscopically observed a lung cancer cell line, A549 which was treated with interferon-$\gamma$. We observed A545 treated with interferon-$\gamma$ was dying fragmented. And so, we performed this study to find out that the mechanism of antitumor cytotoxic effect of interferon-$\gamma$ be apoptosis. Method: We treated A549, human lung cancer cell line with various concentration of interferon-$\gamma$ and quantified its cytotoxic effect of various periods, 24 hours, 72 hours and, 120 hours by MTT(dimethylthiazolyl diphenyltetrazolium bromide) bioassay. Also, after we treated A549 with 100 units/mi of interferon-$\gamma$ for 120 hours, we observed the pattern of cell death with inverted microscope and we extracted DNAs from the dead A549 cells and observed the pattern of 1.5% agarose gel electrophoresis with ethidium bromide staining. Result: 1) Cytotoxic effect of interferon-$\gamma$ on A549: For the first 24 hours, threre was little cytotoxic effect and for between 24 hours and 72 hours, there was the beginning of cytotoxic effect and for 120 hours there was increased cytotoxic effect. 2) Pattern of A549 cell death by interferon-$\gamma$: We observed with inverted microscope that A549 cells were dying fragmented. 3) DNA ladder pattern of gel electrophoresis: We observed DNA ladder pattern of gel electrophoresis of extracted DNAs from dead A549 cells. Conclusion: We concluded that the mechanism of interferon-$\gamma$induced cytotoxicity on lung cancer cell line, A549 be via apoptosis.