• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3562-3569
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• 2013

The performance of concrete structure decreases with change in time and the external environment. In order to reinforce the structure, the research about new material development and application of newly developed materials are widely conducted. In the case of composite FRP, it received good attention in the academia due to its high intensity-weight ratio, excellent corrosion resistency as well as good workability. When applying at the construction field, however, the utilization of FRP did not increase as much due to lack of reliability and design standard. Current study investigated the material characteristics during the temperature change at high temperature and the structural behavior from restraint effect for GFRP reinforcing materials. Two experimental variables were set in this study: GFRP reinforcements due to tensile properties of temperature and restraint compression effects. Three concrete specimen were selected for each set temperatures. For this reason, as a variable to experiment with the effects confined compression concrete members value and tensile properties with temperature reinforcement GFRP, experiment produced three pieces each for each set temperature, the concrete specimen, which is confined in the GFRP was selected each I did. For the temperature change during the experiment, the concrete specimen were mounted in order to expose to experimental high temperature for certain period of time. For compression performance evaluation, reinforcement effect from horizontal constraint of the fiber were measured using an Universal Material Testing Machine (UTM). Finally, this study revealed that the binding characteristics of GFRP materials from temperature change decreased. Also, this study showed that the maximum compression intensity decreased as the temperature increased up to $150^{\circ}C$ in the constraints ability of the GFRP reinforcements during the horizontal constraint of concrete.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.4
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• pp.553-567
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• 2011

Since their establishment in 1999, Regional Development Agencies in England have been a critical catalyst for sustaining regional development, by linking the central government and the region. Nevertheless, the new Coalition Government formed in May 2010 is to abolish RDAs and is to be replaced by Local Enterprise Partnerships(LEP). This article looks at the performance and the present reform process of the English Regional Development Agencies(RDA). It argues that RDAs have been a sort of laboratory to expose the possibility of realizing the new regionalist approach away from the government-centered approach. Nevertheless, the case of RDAs in England shows that the RDA model is less likely to be effective without substantial devolution. It shows that the extent to which RDAs contribute to the regional economy tends to be much higher in soft infra-centered projects, such as business supports and skills development, than physical infrastructure projects. It argues that the LEP model, which is to replace RDAs, is controversial, especially in terms of spatial boundary and financial structure.

• Korean Journal of Environmental Biology
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• v.29 no.3
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• pp.171-179
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• 2011

The legally protected trees distributed in Gwangju City is 68 individuals belong to 9 taxa. Among the legally protected trees recorded in environment white paper, Quercus dentata located in Gwangsan-gu Eunnam-dong Shinga village must come to correct Quercus liena, Populus nigra var. italica of Byeokjin village of Seo-gu Byeokjin-dong change to Salix glandulosa and Pinus densiflora of Sukjung-dong, Nam-gu should be alter into Pinus densiflora for. multicaulis. IPCC make an estimate the mean temperature multiplies best $6.4^{\circ}C$ and sea level of 59 cm rises and is warning that the North-Pole glacier may have melted mostly and 95% of bio-species on earth may falls at extinction crisis on the late 21th century. If apply IPCC estimate result to evaluate climate change vulnerability through the legally protected trees of Gwangju City, it should be estimated that mean minimum temperature of the coldest month of Gwangju City in the late 21th century result in higher than $3^{\circ}C$ as mean minimum temperature, January in Cheju Island at present. Therefore, it is estimate that the legally protected trees of Cheju Island such as Pinus thunbergii, Celtis sinensis, Aphananthe aspera and a evergreen broadleaf trees will grow up well in Gwangju City area in the late 21th century. The other hand, P. densiflora for. multicaulis and zelkova serrata as the legally protected trees that appear together in Seoul and Gwangju will be estimate by something to expose show vulnerability in region of Gwangju City.

• ETRI Journal
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• v.38 no.4
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• pp.675-684
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• 2016

This paper demonstrates the effect of fluoride-based plasma treatment on the performance of $Al_2O_3/AlGaN/GaN$ metal-insulator-semiconductor heterostructure field effect transistors (MISHFETs) with a T-shaped gate length of $0.20{\mu}m$. For the fabrication of the MISHFET, an $Al_2O_3$ layer as a gate dielectric was deposited using atomic layer deposition, which greatly decreases the gate leakage current, followed by the deposition of the silicon nitride layer. The silicon nitride layer on the gate foot region was then selectively removed through a reactive ion etching technique using $CF_4$ plasma. The etching process was continued for a longer period of time even after the complete removal of the silicon nitride layer to expose the $Al_2O_3$ gate dielectric layer to the plasma environment. The thickness of the $Al_2O_3$ gate dielectric layer was slowly reduced during the plasma exposure. Through this plasma treatment, the device exhibited a threshold voltage shift of 3.1 V in the positive direction, an increase of 50 mS/mm in trans conductance, a degraded off-state performance and a larger gate leakage current compared with that of the reference device without a plasma treatment.

• IMMUNE NETWORK
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• v.1 no.2
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• pp.162-169
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• 2001

Background: Nitric oxide (NO), a cytotoxic molecule is produced in various tissues including tumor cells during interleukin-2 (IL-2) therapy . Lymphokine-activated killer (LAK) cells are induced during IL-2 therapy, and have cytotoxic activity against tumor cells. The current study investigated the effects of NO synthesized in target cells or exposure of target cells to NO on the sensitivity of target cells to LAK cell cytotoxicity. Methods: Cytotoxicity was measured using 4 h chromium release assays. LAK cells which were induced by a 4 day incubation of BALB/c mouse splenocytes with IL-2 (6,000 IU/mL) were employed as effector cells. RD-995 skin tumor cells originated from a C3H/HeN mouse were employed as target cells. NO synthesis in target cells was induced by a 24 h incubation of RD-995 cells with $IFN{\gamma}$ (25 U/mL), TNF (50 U/mL) and IL-1 (20 U/mL). S-nitrosyl acetylpenicillamine (SNAP), an NO donor, was used to expose target cells to NO. $N^G$-monomethyl-L-arginine (MLA) and carboxy-PTIO were added during cytotoxicity assays to inhibit NO synthesis, and to scavenge NO produced by target cells, respectively. Results: Sensitivity of NO-producing RD-995 cells to LAK cell cytotoxicity was decreased by addition of MLA and carboxy-PTIO during cytotoxicity assays. However, the two reagents had no effect on the sensitivity of non-NO-producing RD-995 cells. Pretreatment of RD-995 target cells with SNAP increased the sensitivity in comparison with untreated cells. Conclusions: Sensitivity of target cells to LAK cell cytotoxicity is increased by target cell NO synthesis or exposure to NO. Further studies are needed to evaluate whether these in vitro results have relevance to in vivo phenomena.

• Journal of Korean society of Dental Hygiene
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• v.8 no.2
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• pp.93-106
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• 2008

This study is to enforce to ready basic data of effective school dental health education for dental caries prevention， relation knowledge of class, feeding practice and snack intake preference actual conditions, food and caries executed investigation by own recording way using questionnaire consisted of dental health education awareness to some business world man high school locating in Kyonggi Province. Analyzes result that total 487 people respond in SPSS WIN 13.0 programs and got following sequence The obtain result were as follows 1. Results about habit of breakfast was the most by 36.1% a student who have breakfast every day, and a student who hardly eat dominated 32.9%. Second-year student hardly had breakfast (p<.01). 2. A student who answer that snack kind that often eat was cookies and snack kind was the most by 37.2%, and a student who answer that symbol drink was a carbonated drink was the most by 50.9%. 3. Relation knowledge degree appeared grand mean among 18 points perfect score by 12.36 with food and caries. Third-year student knowledge degree was the highest, and second-year student was the lowest knowledge degree by class (p<.01). 4. Existence and nonexistence of experience of dental health education appeared a student who experience that take dental health education does not exist by 57.1%. There was experience that take dental health education as class is low by class, and as class is high, experience did not exists (p<.05). 5. Time that take dental health education for the first time was the most by 56.7% a student who respond 'Babyhood', grade in school is low by class 'Babyhood', and is high by class responded 'Middle school'(p<.05). 6. Awareness of dental health education necessity 'may educate dental health and does not' a student 56.3%, half was looked attitude which students who exceed are insincere about dental health education necessity. 7. When educate dental health, contents was the most by 44.6% 'brushing and mouth article directions' to be educated importantly, and was expose by caries 31.2%, gum disease 10.1%, scaling 9.0%, prosthetic dentistry and implant 5.1% period of ten days, third-year student 50.8% said that 'brushing and mouth article directions' is important (p<.05). Dental health education is practiced during life, and is a teaching that should be remembered. Need to develop epoch-making and interesting education program that is correct in subject to do as quickly as possible, and should be achieved major road of dental hygienist. Dental hygienist will have to settle as quickly as possible as expert of prevention that is natural business and education and help in dental health education development under effort between country and dental association effective.

• Journal of The Korean Association of Information Education
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• v.20 no.3
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• pp.293-302
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• 2016

It is the latest fashion of interesting with software education in public school environment and also consider as high priority issue of curriculum for college freshman with programming 101 courses. The block-based programming tool is used widely for the beginner and provides several positive features compare than text-based programming language tools. To measure quality of programming code elaborately which is based script language, it is need to very tough manual process. As a result the previously research related with evaluation of block-based script code has been focused very simple methods in which normalize the number of blocks used which is related with programming concept. In such cases in this, it is difficult to measure structural vulnerability of script code and implicit programming concept which does not expose. In this research, the framework is proposed which enable to measure and evaluate quality of code script of block-based programming tools and also provides method to find of vulnerability of script code. In this framework, the quality metrics is constructed to structuralize implicit programming concept and then developed the quality measure and vulnerability model of script to improve level of programming. Consequently, the proposed methods enable to check of level of programming and predict the heuristic target level.

• Journal of Science Education
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• v.33 no.2
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• pp.258-270
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• 2009

Science textbook is the most frequently used teaching material in elementary schools of the United States and Korea. Elementary science textbooks of the United States and Korea are analyzed to find out the educational objectives and characteristics of contents shown in textbooks. About 100 pages each in the first grade and fourth grade science textbooks each nations are selected randomly for educational objective analysis. Life science contents of 1st to 6th grade are analyzed from elementary science textbooks of the United States and Korea. The analyzed textbooks in Korea are 'Wise life,' an integrated subject with social studies and science, and 'science.' The analyzed elementary science textbooks of the United States are Harcourt Science, which is one of the frequently used textbooks. The educational objective framework used includes science knowledge, scientific inquiry, scientific attitude, STS, and philosophy and history of science. The results show science textbooks of the United States emphasize scientific knowledge more than scientific inquiry. Korean science textbooks emphasize scientific inquiry more than scientific knowledge. Elementary science textbooks of the United States present some life science topics redundantly and expose more difficult topics than Korean.

• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.715-722
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• 1995

Orthodontic tooth movement in response to orthodontic force results from actions of osteoclasts and osteeoblasts in the cell level. Convincing evidence has now been provided to support the view that osteoclasts are derived from mononuclear cells that originate in the bone marrow or other hematopoietic organs and they migrate to the bones via vascular routes. Nitric oxide(NO), which accounts for the biological properties of endothelium-derived relaxing factor(EDRF), is the endogenous stimulator of soluble guanylate cylase. The discovery of the formation of nitric oxide(NO) from L-arginine in mammalian tissues and its biological roles has, in the last 7 years, thrown new light onto many areas of research. Data from experiments in vitro showed that N-metyl-L-arginine(L-NMA) and L-nitro-L- arginine(L-NAME) are competitive inhibitors of nitric oxide synthase. This study suggest that the multinucleated cells in our culture have characteristics of osteoclasts and that the potential bone cell activity of nitric oxide in vitro may be mediated in part by stimulation of marrow mononuclear cells to form osteoclast-like cells. Bone marrow cells were obtaineed from tibia of 19-days old chick embryo. After sacrifice, tibia was quickly dissected and the bone were then split to expose the medullary bone. The cells were attached for 4 hours and the nonadherent cells were collected. Marrow cells weere cultured in 96-well plate in medium 199. To examine the number of TRAP-positive multinucleated cells(MNCs), $10^{-8}\;M\;Vit=D_3$ and various concentration of L-NMA and L-NAME weere added at the beginning of cultures and with each medium change. After 7 days of culture. tartrate-resistant acid phosphatase(TRAP) staining was performed for microscopic evaluation. Cells haying more than three nuclei per cell were counted as MNCs. The obsrved results were as follows;1. 1,25-dihydroxyvitamine $D_3$ stimulated the osteoclast-like multinucleated cells in cultures of chick embryo bone marrow. 2. Nitric oxide synthase inhibitors(NOSI ; N-NMA, N-NAME) stimulated the osteoclast-like cells in cultures of chick embry bone marrow. 3. 1,25-dihydroxyvitamine$D_3$ and nitric oxide synthase inhibitors did not appear to have additive effect on the generation of TRAP-positive MNCs. These results suggest that nitric oxide synthase inhibitors may stimulate the osteoclast-like multinucleated cell formation and fusion in cultures of chick bone marrow.

• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.51-63
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• 1999

Exposure of the root surface due to gingival recession after periodontal surgery, elicit pain response when exposed to mechanical, heat, chemical or osmotic irritation. Especially patients treated with periodontal surgery, show high frequency. There have been reports that the 1 out of 7 patients complains of dentinal hypersensitivity. There have been many studies on the clinical effects of various materials on the treatment of dentinal hypersensitivity. The purposes of this study were to evaluate the effect of sodium chloride and potassium oxalate and to observe the relationship between the dentinal hypersensitivity and surface characteristics such as dentinal tubule size and number. This study included 20 teeth which were scheduled for extraction and had no pulpal disease. These teeth were divided into Root planing group, EDTA group, NaCl group and Oxalate group. Dentinal hypersensitivity is measured by tactile, pressured air and cold water using NRS (Numerical Rating Scales). Teeth were extracted under local anesthesia and each specimen was sectioned to a size about 3 X 5 mm and was examined under the scanning electron microscope (X2,000) The results were as follows, 1. The EDTA group exhibited significantly increased dentinal hypersensitivity comparing with the other groups. 2. The NaCl and Oxalate groups showed significantly reduced dentinal hypersensitivity comparing with the EDTA group. 3. As a method for dentinal hypersensitivity measurement, it was presumed thet tactile sensitivity test was not sensitive method but air blast test and cold water test were adequate method. 4. In a SEM study, the root planing group exhibited amorphous smear layer and showed no dentinal tubule orifice, but the EDTA group showed the large number of dentinal tubules. On the other hand, the NaCl and Oxalate groups did not show exposed dentinal tubules. The NaCl group showed more rough root surface than the EDTA group, and the Oxalate group showed many participates to be presumed as calcium oxalate particle. As the results from this study, root planing couldn't expose the dentinal tubule and NaCl and potassium oxalate occluded exposed dentinal tubule effectively. Dentinal hypersensitivity has close relationship with the exposure of dentinal tubules, especially with it's size and number.