• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.107-114
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• 2013

In this study we experimentally evaluated an impact resistant performance of fiber reinforced concrete in the moment of explosion by high-velocity projectile with emulsion explosive. To assess the impact resistance, we conducted the impact test of high-velocity projectile which reaches an impact speed of 350 m/s and the experiment of contact exploding emulsion explosive. As a result, bending and tensile performance depending on type of PVA, PE fiber (polyvinyl alcohol fiber, polyethylene fiber) and steel fiber affects destruction of rear side in the form of spalling. Destroying the backside of the concrete compressive strength compared to suppress the bending and tensile performance is affected. In addition, the experiment shows that the destruction patterns of concrete specimen producted by high velocity impact and contact explosion are significantly similar. Therefore, it is possible to predict the destruction patterns of specimens in the situation of contact explosion by high-velocity projectile.

• Journal of Korean Association for Spatial Structures
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• v.9 no.2
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• pp.45-52
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• 2009

This paper experimentally evaluates the strength characteristics of precast column-R.C. foundation anchor joint subjected to the cyclic horizontal load. The study presents differences in accurate stress transfer path and destruction mechanism between the concrete structural body applying the precast column-R.C. foundation anchor joint and the concrete structural body applying the steel joint. the result from width load experiment on reinforcing steel under the cyclic horizontal load provides the necessary minimum insertion length to construct the precast column-R.C. foundation anchor joint. This study also presents the accurate stress transfer path and destruction mechanism on the anchor joint th meet the customer's requirements, comparing stress transfer path and destruction mechanism provided by the experiment and those provided by the product manual. Eventually, this study presents all the necessary fundamental data to provide the construction design with accurate number of reinforcing steel, diameter of the steel, fixation length of the steel, etc. to build the optimum precast concrete column.

• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.53-63
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• 2005

Number of fixtures supporting prosthesis for rehabilitation of partial edentulism in distal area is an important factor in distal area to the bone tissue response around dental implant. Optimal number and optimal positioning of dental implant has leaded to the stable condition of bone tissue and successful long-term treatment outcome. This clinical and radiographic study was performed to document and evaluate the short-term result of occlusal rehabilitation by means of implant-supported fixed prostheses (ISPs) especially for partial edentulism in distal area in patients treated for advanced periodontal disease and to verify the number of fixture affecting the bone tissue response. A total of 30 consecutive patients referred because of advanced periodontal disease were included. Before the implant therapy was initiated, periodontal treatment was performed and the outcome evaluated during at least a 6-month period. An individual maintenance care program was designed for each patient. All 75 implants were placed using a 2-stage surgical approach. The patients were divided into 2 groups, in one of which two fixtures were placed and in the other of which three fixtures were placed with tripodal geometry. Following installation of the ISPs, all patients underwent a baseline examination including evaluation of i) oral hygiene, and ii) periodontal/ peri-implant conditions, and iii) radiographs. These examinations were repeated annually during the 1 or 2-year observation period. The results were as follows: 1.No single implant was lost during the observation follow-up period. 1.The percentage of plaque harboring surfaces and bleeding units upon probing were found to be low (<10%), and no soft tissue complications were recorded. 1.Two-fixture group showed bone destruction ranged from 0.0mm to 1.5mm and the mean was 0.31mm. Three-fixture group showed more bone destruction of 0.51mm. There was no statistically difference between two groups. These results suggested that the factor for success is not the number of fixture but the strict maintenance of peri-implant tissue health and initial stability of fixture.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.161-175
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• 1996

There were many reports that elevations in the levels of active and latent collagenase in gingival crevicular fluid(GCF) have been correlated positively with periodontal disease activity. To provide a simple diagnostic approach for testing GCF collagenolytic activity, the detection limit of enzyme activity was compared using radiofibril assay(Sodek et.al.1981) and spectrophotometric collagenolytic assay(Nethery et al. 1986). The detection limits of both assay for standard bacterial enzyme were similar and the radiofibril assay showed a little (1/2) lower detection limit for tad pole collagenase. To evaluate the relationship between periodontal tissue destruction and the collagenolytic activity, GCF was collected, and latent and active enzyme activities were measured by a spectrophotometric collagenolytic assay. Twelve subjects showing progressive lesions were selected according to the presence of immediate tissue destruction, frequent abscess formation, and increasing need for tooth extraction, and the absence of underlying systemic disease and previous antibiotic medication history within 6 months. Comparisons were made between sites with either: 1) inflammation with a previous history of progressive loss of periodontal tissue and bone support(2l progressive sites): 2) previous history of bone loss and periodontal destruction but now clinically stable(12 comparably stable sites); or 3) no loss of periodontal tissue and bone support(11 control sites including 5 gingivitis sites and 6 healthy sites). Active collagenase activity was the highest in the progressive sites and decreased in the order of the gingivitis sites, the stable sites, and the healthy sites. The total enzyme activity was $2{\sim}3$ fold higher in the progressive sites and the gingivitis sites, compared to the stable and the healthy sites. The ratio of active to total collagenolytic activity was twice in the progressive sites. Analysis of active collagenase level(5mU) and the ratio of active to total collagenolytic activity(0.8) as a diagnositic test indicates that these measurements have the sensitivity of 0.81 and 0.86, the specificity of 0.70 and 0.65, and the overall agreement of 0.75 and 0.73, respectively. Thus, this method has significant merits as a diagnostic tool to determine wherher the site is in a state of remission or progression.

• Journal of the Korean Society of Costume
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• v.60 no.5
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• pp.117-127
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• 2010

In this study, hyperspace is a result of imagination created by means of facts and fiction, represents a transfer to determination and indetermination, and means an extension to an open form. In other words, hyperspace is a high dimensional space expanded to imagination through the combination of the viewpoint on facts in this dimension and fiction. When the 2D plane surface or 3D symmetry is destroyed, or when the frame is twisted or entangled, the non-Euclidean geometry is created eventually. And when the twisting leads to transmutation and the destruction of the form reaches the extreme; this in turn became the twisting like Mbius band. Likewise, the non-Euclidean geometry is co-related to the asymmetry of the Higgs mechanism. When the 'destruction of symmetry' is considered, symmetric theory and asymmetric world can be connected. The asymmetry in turn can maintain balance by arranging the uneven weights at different distances from the shaft. Moreover, at this the concept of the upper, lower, left and right, which was included in the original form, may be crumbled down. The destruction of the symmetry is essential in order to present forecast that coincides with the phenomenon of the real world. Non-Euclidean geometry characteristic is expressed by asymmetry, twists, and deconstruction and its representative characteristic is ambiguity. The boundary between the front, back, upper, lower, inner and outer is unclear, and it is difficult and vague to pinpoint specific location. The design that does not clearly define or determine the direction of wearing costume is indeed the non-oriented design that can be worn without getting restricted by specific direction such as front and back. Non-Euclidean geometry characteristic of hyperspace have been applied to create new shapes through the modification of the substance from traditional clothing of the eastern world to modern fashion. The way of thinking in the 'hyperspace' that used to be expressed in the costumes of the east and the west in the past became the forum for unlimited creation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.2
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• pp.131-139
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• 1992

Based on the equi-flooding line theory, this study suggests method of evaluating safety of detent tion reservoirs with drainage pumping facilities in Seoul metropolitan area, and derives equi-flooding lines according to destruction frequency for each detention reservoir. In most part of detention reservoirs, its flood prevention are so much dependent upon drainage capacity that inland flooding prevention can be serious problems in case of its malfunction. In this study, the detention reservoirs which are below 5 year destruction frequency estimated as 29.3%, and below 10 year as 39.6% of the total. To improve reservoir safety, the detention reservoir capacities (including drainage and pumping capacity) should be upgraded above 20 year in its destruction frequency, and its reinforcement capacities are calculated.

• The Journal of Korean Medicine
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• v.23 no.4
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• pp.98-104
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• 2002

Objectives: Calpain, a calcium-dependent cysteine proteinase, may be one of the proteolytic enzymes that mediate cartilage degradation associated with rheumatoid arthritis. The object of this study is to ascertain immunohistochemically whether calpain is present in the inflamed joints of collagen-induced arthritis of rats, and examine the effect of Cortex Acanthopanacis Senticosi on the expression of calpain. Methods: Male Lewis rats, around 200g of body weight, were immunized with bovine type II collagen. After 3 weeks from first immunization, rats were divided into arthritic control (n=6) group and Cortex Acanthopanacis Senticosi-treated (n=6) group. Non-immunized rats served as the normal (n=6) group. All animals were sacrificed at 15 days post-treatment and tibiotarsal joints were removed. Calpain immunohistochemistry was performed on the midsagittal section of the tibiotarsal joint. Results: All animals of the control and treated groups showed ankylosing osteoarthritis. However, the animals of the treated group showed alleviation in the fibrous ankylosis, destruction of articular cartilage and destruction of subchondral bony tissue compared with the animals of the control group. Calpain was expressed in the chondrocyte lacunae of growing articular cartilage, in the skeletal muscle fibers, in the peripheral nerves, and in the vessel walls around the joints of all groups. In the control and treated groups, calpain was also expressed in proliferating synovial epithelia, subsynovial stroma cells, surface of articular cartilage, and fibrous pannus around destructive subchondral bony tissue. However, the expression density of calpain in the treated group was diminished compared with the control group, especially in surface of articular cartilage and fibrous pannus. Conclusions: These observations indicated that calpain plays an important role in the destruction of cartilage and bone in collagen-induced arthritis of rats, and also indicated that Cortex Acanthopanacis Senticosi inhibits the development of arthritis by decreasing the expression of calpain.

• Journal of the Korean Society of Costume
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• v.65 no.4
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• pp.76-90
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• 2015

Based on a concept of Nietzschean nihilism, this study aimed at interpreting the nihilism in arts and its expressions, also analyzing the modern fashion collection from the same angle. The research was centered on arts after 1980, when post-modern formal destruction expanded in earnest and on the fashion collection after the 20th century, easily accessible to data. Particularly, it set 1994 nihilism collection by Alexander McQueen, a representative nihilist fashion designer as a starting point. Nietzsche mentioned that true arts may be achieved when Apollonian characteristics including a bodily sensory system and an idealization process and Dionysian characteristics including every human feeling are integrated. Besides, he emphasized the importance of an artist being represented as an image of ${\ddot{U}}bermensch$. The ${\ddot{U}}bermensch$ image, reflected in arts and artistic nihilism, represents themes of violence/death, realistic/unrealistic expressions, human body/inhuman aversion materials and the transmutation of a form. Fashion collection expressions, owing to the special characteristic of the show form unlike other arts, were segmented as a realistic ${\ddot{U}}bermensch$ image using a model in a theme, expression, material and form. The theme of violence/death was divided into the death of human and a society. Human life/death was expressed as destruction of human weakness and self-identity, sexual objectification and violence, and social death as destruction and conflict of a class, nation, culture and nature. As for the expression, it was divided into the realistic expression of the primitive/natural and directing of an unrealistic atmosphere using a show.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.3
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• pp.163-168
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• 2003

The reactive oxygen species (ROS) are considered to be an important mediator in pancreatic ${\beta}$ cell destruction, thereby triggering the development of insulin-dependent diabetes mellitus. In the present study, HIV-1 Tat-mediated transduction of Cu,Zn-superoxide dismutase (SOD) was investigated to evaluate its protective potential against streptozotocin (STZ)-induced cytotoxicity in insulin-producing MIN6N cells. Tat-SOD fusion protein was successfully delivered into MIN6N cells in a dose-dependent manner and the transduced fusion protein was enzymatically active for 48 h. The STZ induced-cell destruction, superoxide anion radical production, and DNA fragmentation of MIN6N cells were significantly decreased in the cells pretreated with Tat-SOD for 1 h. Furthermore, the transduction of Tat-SOD increased Bcl-2 and heat shock protein 70 (hsp70) expressions in cells exposed to STZ, which might be partly responsible for the effect of Tat-SOD. These results suggest that an increased of free radical scavenging activity by transduction of Tat-SOD enhanced the tolerance of the cell against oxidative stress in STZ-treated MIN6N cells. Therefore, this Tat-SOD transduction technique may provide a new strategy to protect the pancreatic ${\beta}$ cell destruction in ROS-mediated diabetes.

• Korean Journal of Pharmacognosy
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• v.39 no.1
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• pp.1-6
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• 2008

AIF has been formulated using three herbs known to have anti-inflammatory and anti-osteolytic effects. In this study, the potential therapeutic effects of AIF for osteoarthritis were assessed in vitro and in vivo. The effects of AIF on the cartilage and bone protection (MMP-13 expression, GAG degradation, OPG release) were examined, in vitro. In addition, the therapeutic effect of AIF was evaluated using a chemical-induced osteoarthritis rat model. Rats were injected with iodoacetate intraarticularly in one knee joint and treated with the oral administration of 100 mg/kg AIF-glucosamine once a day for 3 weeks. And then, destruction of cartilage and bone was evaluated by histopathological assessment. AIF significantly inhibited the production of MMP13 and GAG in a dose dependent manner in vitro. Also, AIF increased the production of OPG. In OA rat model, the AIF-glucosamine treated group reduced cartilage destruction, compared to vehicle or glucosamine treated group. AIF showed potent protective effects for the destruction of cartilage and bone, in vitro and in vivo. These results suggest that AIF contains effective compound(s) which may modify the progression of arthritis.