• Computers and Concrete
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• v.21 no.1
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• pp.67-74
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• 2018

A differential scheme based micromechanical framework is proposed to obtain the effective properties of the saturated concrete repaired by the electrochemical deposition method (EDM) considering the interfacial transition zone (ITZ) effects. The constituents of the repaired concrete are treated as different phases, consisting of (micro-)cracks, (micro-)voids and (micro-)pores (occupied by water), deposition products, intrinsic concrete made up by the three traditional solid phases (i.e., mortar, coarse aggregates and their interfaces) and the ITZs. By incorporating the composite sphere assemblage (CSA) model and the differential approach, a new multilevel homogenization scheme is utilized to quantitatively estimate the mechanical performance of the repaired concrete with the ITZs. The CSA model is modified to obtain the effective properties of the equivalent particle, which is a three-phase composite made up of the water, deposition products and the ITZs. The differential scheme is employed to reach the equivalent composite of the concrete repaired by EDM considering the ITZ effects. Moreover, modification procedures considering the ITZ effects are presented to attain the properties of the repaired concrete in the dry state. Results in this study are compared with those of the existing models and the experimental data. It is found that the predictions herein agree better with the experimental data than the previous models.

• Korean Journal of Social Welfare
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• v.65 no.3
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• pp.5-28
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• 2013

As the interests in social inclusion is increasing, researches on social inclusion in the welfare of the disability positively are being implemented lately. It is required to be the reconsideration on previous perspectives and suggestion of the necessity of a new concept for acquiring equal accessibility on rights and resources, etc as a citizenship. It is evaluated to be useful as the perspective or approach of social inclusion in suggestion of policies and practices tasks for enhancing quality of life of the disadvantaged including the disabled and for their participating fully in overall social scopes. Therefore, firstly on tried to make understanding in each concept, constituents, characteristic, usefulness and restriction, etc about both of social exclusion and inclusion fundamentally. On discusses how to conceptualize social inclusion of the disabled, and meanings in applying the concept or approach of social inclusion to welfare of the disability through the based mentioned results.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.1
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• pp.71-84
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• 2007

Statement of problem: Implant surface characteristics plays an important role in clinical success and many studies have been made for improvement of success by changing surface roughness. Purpose: Appropriate increase of surface roughness increases the activity of osteoblast and enhance contact and retention between bone and implant. Material and method- Machined, SLA and RBM surface implants, which are the most commonly used implants were implanted into the tibia of rabbits and after 1 week, 4 weeks, 8 weeks and 12 weeks there were histologic and histomorphometric analysis and study for bone gradient and change of Ca/P ratio using EDS(Energy Dispersive X-ray Spectroscope). Results: Comparison of bone-implant contact showed no significant difference among each implant. In comparison of bone area rates, SLA showed higher value with significant difference at 1 week and 4 weeks, and SLA and RBM at 8 weeks than Machined implant (p<0.05). In analysis of bone constituents with EDS, titanium was specifically detected in new bones and the rates were constant by surface treatment method or period. In case of Ca/P ratio, according to surface treatment method, each group showed significant difference. Lots of old bone fragments produced during implantation remained on the rough surface of RBM implant surface and each group showed histological finding with active synthesis of collagen fibers until 12 weeks. In transmission electronic microscopic examination of sample slice after elapse of twelve weeks, tens nm of borderline (lamina limitans like dense line)was seen to contact the bone, on the interface between bone and implant. Conclusion: SLA and RBM implant with rough surface shows better histomorphometrical result and the trend of prolonged bone formation and maturation in comparison with Machined implant. In addition, implant with rough surface seems to be helpful in early stage bone formation due to remaining of old bone fragments produced in implantation. From the results above, it is considered to be better to use implant with rough surface in implantation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.329-334
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• 2017

In this study, a new granular type mouthwash with equivalent antibacterial activity to marketed liquid type mouthwash was developed using a material called magnesium aluminometasilicate (Neusilin). This material adsorbs the surface of granules to improve the flowability of granules due to the formation of a eutectic mixture of the main constituents, which have improved flow properties and rapid disintegration time and little residue in the oral cavity. The characteristics of the granules were improved when the amount of Neusilin was 10% or more according to measurements of the granule properties, such as flowability. In addition, a disintegration test in artificial saliva and a sensory test in the human oral cavity were carried out to confirm the improved disintegration characteristics and sensory test results. The antimicrobial test confirmed similar antibacterial activity to that of the liquid oral cleanser already sold in the market. The granular oral cleanser composition prepared in this study can be used for the development of pharmaceuticals containing different drugs with similar characteristics as eutectic mixtures at the same time, which is considered to be useful in the development of medicines in the pharmaceutical industry.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.152-152
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• 2017

Titanium and its alloys have been widely used for biomedical applications. However, the use of the Ti-6Al-4V alloy in biomaterial is then a subject of controversy because aluminum ions and vanadium oxide have potential detrimental influence on the human body due to vanadium and aluminum. Hence, recent works showed that the synthesis of new Ti-based alloys for implant application involves more biocompatible metallic alloying element,such as, Nb, Hf, Zr and Mo. In particular, Nb and Hf are one of the most effective Ti ${\beta}$-stabilizer and reducing the elastic modulus. Plasma electrolyte oxidation (PEO) is known as excellent method in the biocompatibility of biomaterial due to quickly coating time and controlled coating condition. The anodized oxide layer and diameter modulation of Ti alloys can be obtained function of improvement of cell adhesion. Silicon (Si) and magnesium (Mg) has a beneficial effect on bone. Si in particular has been found to be essential for normal bone and cartilage growth and development. In vitro studies have shown that Mg plays very important roles in essential for normal growth and metabolism of skeletal tissue in vertebrates and can be detected as minor constituents in teeth and bone. Therefore, in this study, Si and Mg coatings on the hydroxyapatite film formed Ti-29Nb-xHf alloys by plasma electrolyte oxidation has been investigated using several experimental techniques. Ti-29Nb-xHf (x= 0, 3, 7 and 15wt%, mass fraction) alloys were prepared Ti-29Nb-xHf alloys of containing Hf up from 0 wt% to 15 wt% were melted by using a vacuum furnace. Ti-29Nb-xHf alloys were homogenized for 2 hr at $1050^{\circ}C$. The electrolyte was Si and Mg ions containing calcium acetate monohydrate + calcium glycerophosphate at room temperature. The microstructure, phase and composition of Si and Mg coated oxide surface of Ti-29Nb-xHf alloys were examined by FE-SEM, EDS, and XRD.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.3
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• pp.125-129
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• 2008

The aim of this study was to determine whether single nucleotide polymorphisms (SNPs) of matrix metallopeptidase 2 (MMP2) are associated with obesity. MMP2 is an enzyme with proteolytic activity against matrix and nonmatrix proteins, particularly basement membrane constituents. To identify the relationship between polymorphisms of MMP2 and overweight/obese, we genotyped 5 SNPs (rs17242319, rs1053605, rs243849, rs2287074, and rs10775332) of the coding region of MMP2 using the Golden Gate assay on an Illumina BeadStation 500 GX. One hundred and forty two overweight/obese ($BMI\;{\ge}\;23$) and 145 normal (BMI 18 to < 23) subjects were analyzed. SNPStats, Haploview, HapAnalyzer, SNPAnalyzer, and Helixtree programs were used for the analysis of genetic data. A linkage disequilibrium (LD) block was discovered among the 5 SNPs selected, including rs17242319, rs1053605, rs243849, and rs2287074. Of the 5 polymorphisms, 2 synonymous SNPs [rs17242319 (Gly226Gly) and rs10775332 (Phe602Phe)] were found significant associations with overweight/obese. Recently, rs1132896 replaced rs17242319 as a new number (SNP database, BUILD 129). In haplotype analysis using Haploview, a haplotype (haplotype: CCCA) containing a meaningful polymorphism (rs17242319) was found to be significantly different. The results suggest that MMP2 may be associated with overweight/obese in Korean population.

• The Korean Journal of Food And Nutrition
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• v.33 no.5
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• pp.576-583
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• 2020

The purpose of this study was to compare the quality characteristics of silken tofu products from the commercial market in Korea. Seven types of commercial silken tofu were sampled and their physicochemical properties, including soluble solid contents, salinity, pH, total acidity, moisture contents (total solid contents), crude protein and fat contents were evaluated. The TPA results suggest that the texture of silken tofu was very different from one another according to the type of and the amount of coagulant. The commercial silken tofu showed a range of pH 5.53~6.48, total acidity of 0.12~0.32%, soluble solid contents of 2.62~5.07 °Brix, salinity of 2.28~4.30%, and moisture contents of 87.10~92.24%, respectively. In terms of the coagulant of tofu, besides the GDL (glucono-δ- lactone), other coagulants such as MgCl₂ for making 'silken tofu' in the Korean tofu market. The quality characteristics differed depending on the constituents of sample and the coagulants of tofu used. These results are expected to be useful in identifying new trends in the domestic silken tofu industry.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.159-160
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• 1998

Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.93-107
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• 2005

The estuary of Nakdong River area including Noksan industrial complex and Busan New Port is composed of thick unconsolidified sediments containing abundant clay, and thus is a potential hazardous area of ground subsidence. We analyzed mineral compositions and geotechnical properties of the clay sediments that sampled from 4 boreholes of the area, and examined vertical variations and their correlations. The results showed correlations between some mineral constituents and geotechnical properties of clay sediments. A positive correlation showed between quartz content and wet unit weight, whereas a negative correlation showed between quartz content and liquid limit. Feldspar content and water content showed a negative correlation, whereas content of clay minerals and liquid limit showed a positive correlation. And also, there is a negative correlation between content of clay minerals and wet unit weight. Correlation equations are obtained from the multiple regression analyses among plastic index, content of clay mineral, smectite and clay fraction.

• Journal of Engineering Education Research
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• v.11 no.2
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• pp.42-49
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• 2008

Though the 'Program Educational Objectives' is the first and important criterion in ABEEK's engineering education accreditation, exact meaning and implementation methods have not been understood well. It was often confused with 'Program Outcomes' and its implementation and evaluation methods do not reflected well on the concepts of "outcomes based and demand driven education". A new implementation model for 'Program Educational Objectives' has been developed using step by step application. The model explains the meaning of every step (phase), and key constituents in each phase. The specialization and CQI of the program could be satisfied by applying the model properly.