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Hydraulic Stability and Wave Transmit Property of Stacked Geotextile Tube by Hydraulic Model Test (수리모형시험을 통한 다단식 지오텍스타일 튜브의 안정성 및 파랑 전달특성에 관한 연구)

  • Oh Young In;Shin Eun Chul
    • Journal of the Korean Geotechnical Society
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    • v.21 no.2
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    • pp.57-65
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    • 2005
  • Geotextile have been used for the past 30 years for various types of containers, such as small sandbag, 3-D fabric forms and aggregate filled gabion etc. While they are mainly used for flood and water control, they are also used against beach erosion fir shore protection. Especially, large-sized geotextile tube structures are used in various innovative coastal systems involving breakwaters. This paper presents the hydrodynamic behavior of geotextile tubes based on the results of hydraulic model tests. These tube are generally about 1.0 m to 2.0 m in diameter, thou띤 they can be sized for any application. The tubes can be used solely, or stacked to add greater height and usability. Stacked geotextile tubes will be created by adding the height necessary for some breakwaters and embankment, therefore increasing the usability of geotextile tubes. The hydraulic model test was conducted as structural condition and wave conditions. Structural condition is installation direction to the wave (perpendicular and 45$^{circ}$$), and wave condition is varied with the significant wave height ranging from 3.0 m to 6.0 m. Compared with previous test result, the stacked geotextile tube is more stable against wave attack than single tube. Also, the case of none-water depth above crest is more stable than 0.5H of water depth above crest. The incline installed stacked tube is more effective for wave adsorption.

Estimation of Genetic Parameters for Calving Ease by Heifers and Cows Using Multi-trait Threshold Animal Models with Bayesian Approach

  • Lee, D.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.8
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    • pp.1085-1090
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    • 2002
  • Genetic parameters for birth weights (BWT), calving ease scores observed from calves born by heifers (CEH), and calving ease scores observed from calves born by cows (CEC) were estimated using Bayesian methodology with Gibbs sampling in different threshold animal models. Data consisted of 77,458 records for calving ease scores and birth weights in Gelbvieh cattle. Gibbs samplers were used to obtain the parameters of interest for the categorical traits in two univariate threshold animal models, a bivariate threshold animal model, and a three-trait linear-threshold animal model. Samples of heritabilities and genetic correlations were calculated from the posterior means of dispersion parameters. In a univariate threshold animal model with CEH (model 1), the posterior means of heritabilities for calving ease was 0.35 for direct genetic effects and 0.18 for maternal genetic effects. In the other univariate threshold model with CEC (model 2), the posterior means of heritabilities of CEC was 0.28 for direct genetic effects and 0.18 for maternal genetic effects. In a bivariate threshold model with CEH and CEC (model 3), heritability estimates were similar to those in unvariate threshold models. In this model, genetic correlation between heifer calving ease and cow calving ease was 0.89 and 0.87 for direct genetic effect and maternal genetic effects, respectively. In a three-trait animal model, which contained two categorical traits (CEH and CEC) and one continuous trait (BWT) (model 4), heritability estimates of CEH and CEC for direct (maternal) genetic effects were 0.40 (0.23) and 0.23 (0.13), respectively. In this model, genetic correlation estimates between CEH and CEC were 0.89 and 0.66 for direct genetic effects and maternal effects, respectively. These estimates were greater than estimates between BWT and CEH (0.82 and 0.34) or BWT and CEC (0.85 and 0.26). This result indicates that CEH and CEC should be high correlated rather than estimates between calving ease and birth weight. Genetic correlation estimates between direct genetic effects and maternal effects were -0.29, -0.31 and 0.15 for BWT, CEH and CEC, respectively. Correlation for permanent environmental effects between BWT and CEC was -0.83 in model 4. This study can provide genetic evaluation for calving ease with other continuous traits jointly with assuming that calving ease from first calving was a same trait to calving ease from later parities calving. Further researches for reliability of dispersion parameters would be needed even if the more correlated traits would be concerned in the model, the higher reliability could be obtained, especially on threshold model with property that categorical traits have little information.

Computing Algorithm for Genetic Evaluations on Several Linear and Categorical Traits in A Multivariate Threshold Animal Model (범주형 자료를 포함한 다형질 임계개체모형에서 유전능력 추정 알고리즘)

  • Lee, D.H.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.137-144
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    • 2004
  • Algorithms for estimating breeding values on several categorical data by using latent variables with threshold conception were developed and showed. Thresholds on each categorical trait were estimated by Newton’s method via gradients and Hessian matrix. This algorithm was developed by way of expansion of bivariate analysis provided by Quaas(2001). Breeding values on latent variables of categorical traits and observations on linear traits were estimated by preconditioned conjugate gradient(PCG) method, which was known having a property of fast convergence. Example was shown by simulated data with two linear traits and a categorical trait with four categories(CE=calving ease) and a dichotomous trait(SB=Still Birth) in threshold animal mixed model(TAMM). Breeding value estimates in TAMM were compared to those in linear animal mixed model (LAMM). As results, correlation estimates of breeding values to parameters were 0.91${\sim}$0.92 on CE and 0.87${\sim}$0.89 on SB in TAMM and 0.72~0.84 on CE and 0.59~0.70 on SB in LAMM. As conclusion, PCG method for estimating breeding values on several categorical traits with linear traits were feasible in TAMM.

Case Study on the Application of Chain Saw Machine for the Underground Marble Quarrying (갱내 대리석 채석을 위한 체인쏘머신 적용 사례연구)

  • Ju, Jaeyeol;Lee, Kwangpyo;Kim, Jaedong
    • Tunnel and Underground Space
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    • v.23 no.3
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    • pp.180-191
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    • 2013
  • The purpose of this research was to find an optimal quarrying for marble by analyzing the applicability and the work efficiency of a chain saw machine newly introduced in the underground Baekwoon mine. From the test results of the physical properties of Baekwoon marble, which affects the efficiency of rock cutting, it was found to have similar physical characteristics as the ones which are now being produced in the other areas in Korea. And especially it shows isotropic property, which can be thought to be advantageous as a dimensional stone. To check the long-term quality of the marble as a stone material, several tests such as corrosion resistance test and abrasion test were carried out. It was found to be vulnerable to acid rain with decrease of weight and seismic wave velocity after applying artificial rain at pH 5.6 for 50 times. The percentage of wear from abrasion test was 22.67%. The working time and cutting speed of the chain saw machine were recorded and analyzed during the test-run at the quarry. The overall work cycle was assorted into 9 unit operations and the operating time per each unit was drawn. The operating times for the two cutting patterns, which could be possibly applicable to the work site, were compared. The results indicated that the pattern B, that the cutting sequence was set to minimize the movement of the machine, showed 6% less working hours than the pattern A, which first cuts the outer boundary. With cutting pattern analysis, the ore body in the Baekwoon mine was 3 dimensionally modeled and a quarrying plan considering the existing conditions of the marble was suggested.

Ginsenoside Rg4 Enhances the Inductive Effects of Human Dermal Papilla Spheres on Hair Growth Via the AKT/GSK-3β/β-Catenin Signaling Pathway

  • Lee, Yun Hee;Choi, Hui-Ji;Kim, Ji Yea;Kim, Ji-Eun;Lee, Jee-Hyun;Cho, So-Hyun;Yun, Mi-Young;An, Sungkwan;Song, Gyu Yong;Bae, Seunghee
    • Journal of Microbiology and Biotechnology
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    • v.31 no.7
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    • pp.933-941
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    • 2021
  • Ginsenoside Rg4 is a rare ginsenoside that is naturally found in ginseng, and exhibits a wide range of biological activities including antioxidant and anti-inflammatory properties in several cell types. The purpose of this study was to use an in vivo model of hair follicle (HF)-mimic based on a human dermal papilla (DP) spheroid system prepared by three-dimensional (3D) culture and to investigate the effect of Rg4 on the hair-inductive properties of DP cells. Treatment of the DP spheroids with Rg4 (20 to 50 ㎍/ml) significantly increased the viability and size of the DP spheres in a dose-dependent manner. Rg4 also increased the mRNA and protein expression of DP signature genes that are related to hair growth including ALP, BMP2, and VCAN in the DP spheres. Analysis of the signaling molecules and luciferase reporter assays further revealed that Rg4 induces the activation of phosphoinositide 3-kinase (PI3K)/AKT and the inhibitory phosphorylation of GSK3β, which activates the WNT/β-catenin signaling pathway. These results correlated with not only the increased nuclear translocation of β-catenin following the treatment of the DP spheres with Rg4 but also the significant elevation of mRNA expression of the downstream target genes of the WNT/β-catenin pathway including WNT5A, β-catenin, and LEF1. In conclusion, these results demonstrated that ginsenoside Rg4 promotes the hair-inductive properties of DP cells by activating the AKT/GSK3β/β-catenin signaling pathway in DP spheres, suggesting that Rg4 could be a potential natural therapy for hair growth.

Effects of pH and Redox Conditon on Silica Sorption in Submerged soils (담수조건(湛水條件)에서 토양산도(土壤酸度)와 산화환원(酸化還元) 전위(電位)가 토양(土壤)의 규산흡착(珪酸吸着)에 미치는 영향(影響))

  • Lee, Sang-Eun;Neue, Heins Ulitz
    • Korean Journal of Soil Science and Fertilizer
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    • v.25 no.2
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    • pp.111-126
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    • 1992
  • Silica sorption isotherm belonged to the C-type with weak L-type characteristics according to the classification system of adsorption isotherm. Silica sorption isothem fitted well to the Freundlich and Tempkin equation but not to the Langmuir equation. The color interference probably due to $Fe^{2+}$ during spectrometric silca determination by Molybdenum-blue method affected the sorption isotherm in reduced soils or low pH. Four parameters such as the intercept of Freundlich equation, the slope of Tempkin equation, the "Silica reactivity", and the "C-type slope", where the last two parameters were termed in the current study, were examined to assess treatment effects on silica sorption. Among them the "C-type slope" was found out to be the best parameter. The C-type isotherms showed the same high correlation coefficient as Freundlich and Tempkin equation when regressed to the sorption isothem. Plotting the C-type slope on a logarithmic scale vs. the pH showed high linearity. Using the "C-type slope" as a perameter, the pH and soil type affected the silica sorption while the effect of redox condtion was not significant. All Fe and Al extracted by the various reagents, and OM were highly correlated to silica sorption. Among them $Fe_d$ was identified as the highest influencing soil property. Since there is no equivalent reliable method to discriminate the forms of the soil Al-oxides their likely importance remains unclear.

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Republic of Korea Entrepreneurship Ecosystem Status and Recognition Research: Focusing on Entrepreneurs, Entrepreneurs Preliminary, Student Centered Comparative Analysis on the Status and Recognition (대한민국 창업생태계 현황 및 인식 연구: 창업가, 예비창업가, 학생을 중심으로 현황 및 인식 비교 분석)

  • Kim, Sung Hoon;Nam, Jung min
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.6
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    • pp.175-183
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    • 2016
  • The government set up "national happiness, the hope of a new era of national vision under' job center of the creative economy" to achieve by national goals in the first and figure achieved through the establishment of new growth engines of the youth unemployment problem solve and national level there are a number of business start-up support. September 8, 2015 announced the Government's look at the '2016 Year of the budget, the government for new growth engines greatly promoted the venture entrepreneurship ecosystem revitalization and research and development (R & D) the business for enhanced performance in 2017. According to the direction of this study is to evaluate the current creative economy business incubator at the comparison whether the correct orientation mainly entrepreneurs, entrepreneurs preliminary recognition of student entrepreneurship ecosystem. Entrepreneurs 113 people in that way, 71 people pre-entrepreneurs, students 60, workers were founding agencies conducted an online survey of 47 people, 16 people Investors, 50 public and 11 additional persons including a total of 368 people. This study is in line with the orientation of these entrepreneurs to create economic status and recognition of the Republic of Korea entrepreneurship ecosystem, pre- entrepreneurs, students will examine the comparative analysis around. Analysis, social perception of entrepreneurship is somewhat higher than it was confirmed that the negative response of 32.2% to 36.3% of positive response. Social awareness of entrepreneurs showed a 2-fold higher response rate than the negative of response of 17.1% to 41.7% responding that positive recognition for the current start-up environment is bad, the response is good response to higher response rate than 23.5% to 41.1% It showed. The percentage of responses that better respect the entrepreneurship environment of the future Republic of Korea showed a higher response rate than the rate of 23% in response to deteriorate to 41.2%, with 52.9% awareness is the percentage that responded that the bad part about the ruthless Korea's entrepreneurship environment in China good part as response rate approximately three times greater than the 17.7% showed high response rates. Social awareness of entrepreneurs experience the presence of the founding start-up experience was confirmed that the more negative the number increases, the more the contrary the number of start-up experience increased awareness of the current and future environment of entrepreneurship was identified as a positive entrepreneurship environment. Also recognized was confirmed to change the parent of the more positive changes in the start-up of entrepreneurs doctor also positive about entrepreneurship, start-up entrepreneurs start with a doctor's motivation for founding non-economic reasons than for economic reasons has confirmed Higher. This study showed the overall level overview analysis of the status and recognition of the Republic of Korea entrepreneurship ecosystem. Future studies need to be a proposal for an existing previous studies for more precise direction to go forth to analyze the entrepreneurship ecosystem with a focus on problems and improvement of the Republic of Korea entrepreneurship ecosystem.

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Effects of High Pressure Treatment on the Microbiological and Chemical Properties of Milk (초고압 처리가 우유의 미생물학적 및 이화학적 특성에 미치는 영향)

  • Lee, Jieun;Choi, Eun-Ji;Park, Sun Young;Jeon, Ga Young;Jang, Ja-Young;Oh, Young Jun;Lim, Seul Ki;Kim, Tae-Woon;Lee, Jong-Hee;Park, Hae Woong;Kim, Hyun Ju;Jeon, Jung Tae;Choi, Hak-Jong
    • Microbiology and Biotechnology Letters
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    • v.42 no.3
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    • pp.267-274
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    • 2014
  • High pressure processing (HPP) is a non-thermal method used to prevent bacterial growth in the food industry. Currently, pasteurization is the most common method in use for most milk processing, but this has the disadvantage that it leads to changes in the milk's nutritional and chemical properties. Therefore, the effects of HPP treatment on the microbiological and chemical properties of milk were investigated in this study. With the treatment of HPP at 600 MPa and $15^{\circ}C$ for 3 min, the quantity of microorganisms and lactic acid bacteria were reduced to the level of 2-3 log CFU/ml, and coliforms were not detected during a storage period of 15 d at $4^{\circ}C$. An analysis of milk proteins, such as ${\alpha}$-casein, ${\beta}$-casein, ${\kappa}$-casein, ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin by on-chip electorophoresis revealed that the electrophoretic pattern of the proteins from HPP-treated milk was different from that of conventionally treated commercial milk. While the quantities of vitamins and minerals in HPP-treated milk were seen to be comparable to amounts found in raw milk, the enzyme activity of lipase, protease and alkaline phosphatase after HPP treatment was reduced. These results suggest that HPP treatment is a viable method for the control of undesirable microorganisms in milk, allowing for minimal nutritional and chemical changes in the milk during the process.

Tissue Culture Method as a Possible Tool to Study Herbicidal Behaviour and Herbicide Tolerance Screening (조직배양(組織培養) 방법(方法)을 이용(利用)한 제초제(除草劑) 작용성(作用性) 및 제초제(除草劑) 저항성(抵抗性) 검정방법(檢定方法) 연구(硏究))

  • Kim, S.C.;Lee, S.K.;Chung, G.S.
    • Korean Journal of Weed Science
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    • v.6 no.2
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    • pp.174-190
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    • 1986
  • A series of laboratory and greenhouse experiments were conducted to find out the possibility of tissue culture and cell culture methods as a tool to study herbicidal behaviour and herbicide tolerance screening from 1985 to 1986 at the Yeongnam Crop Experiment Station. For dehulled-rice culture, pure agar medium was the most appropriate in rice growth campared to other media used for plant tissue culture method. All the media but the pure agar medium resulted in growth retardance by approximately 50% and this effect was more pronounced to root growth than shoot growth. Herbicidal phytotoxicity was enhanced under light condition for butachlor, 2.4-D, and propanil while this effect was reversed for DPX F-5384 and CGA 142464, respectively. And also, herbicides of butachlor, chlornitrofen, oxadiazon, and BAS-514 resulted in more phytotoxic effect when shoot and root of rice were exposed to herbicide than root exposure only while other used herbicides exhibited no significant difference between two exposure regimes. Similar response was obtained from Echinochloa crusgalli even though the degree of growth retardance was much greater. Particularly, butachlor, 2.4-D, chlornitrofen, oxadiaxon, pyrazolate and BAS-514 totally inhibited chlorophyll biosynthesis even at the single contact of root. Apparent cultivar differences to herbicide were observed at the young seedling culture method and dehulled rice cultivars were more tolerant in DPX F-5384, NC-311, pyrazolate and pyrazoxyfen, respectively. For derant than other types or rice cultivar in butachlor, pretilachlor, perfluidone and oxadiazon while Tongil-type rice cultivars were more tolerant in DPXF-5384, NC-311, Pyrazolate and Pyrazoxyfen, respectively. For dehulled rice culture, on the other hand, Japonica-type rice cultivar was less tolerant to herbicides of butachlor, propanil, chlornitrofen and oxadiazon that was reversed trend to young seedling culture test. Cultivar differences were also exhibited within same cultivar type. In general, relatively higher tolerant cultivars were Milyang 42, Cheongcheongbyeo, Samgangbyeo, Chilseoungbyeo for Tongil-type, Somjinbyeo for Japonica-type and IR50 for Indica-type, respectively. The response of callus growth showed similar to dehulled rice culture method in all herbicides regardless of property variables. However, concentration response was much sensitive in callus response. The concentration ranges of $10^{-9}M-10^(-8)M$ were appropriate to distinguish the difference between herbicides for E. crusgalli callus growth. Among used herbicides, BAS-514 was the most effective to E. crusgalli callus growth. Based on the above results, tissue culture method could be successfully used as a tool for studying herbicidal behaviour and tolerance screening to herbicide.

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THE BOND CHARACTERISTICS OF PORCELAIN FUSED BY TITANIUM SURFACE MODIFICATION (타이타늄의 표면개질에 따른 도재 결합 특성)

  • Choi, Taek-Huw;Park, Sang-Won;Vang, Mong-Sook;Yang, Hong-So;Park, Ha-Ok;Lim, Hyun-Pil;Oh, Gye-Jeong;Kim, Hyun-Seung;Lee, Kwang-Min;Lee, Kyung-Ku
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.2
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    • pp.169-181
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    • 2007
  • Statement of problem: Titanium is well known as a proper metal for the dental restorations, because it has an excellent biocompatibility, resistance to corrosion, and mechanical property. However, adhesion between titanium and dental porcelains is related to the diffusion of oxygen to the reaction layers formed on cast-titanium surfaces during porcelain firing and those oxidized layers make the adhesion difficult to be formed. Many studies using mechanical, chemical and physical methods to enhance the titanium-ceramic adhesion have been actively performed. Purpose: This study meant to comparatively analyse the adhesion characteristics depending on different titanium surface coatings after coating the casts and wrought titanium surfaces with Au and TiN. Material and method: In this study, the titanium specimens (CP-Ti, Grade 2, Kobe still Co. Japan) were categorized into cast and wrought titanium. The wrought titanium was cast by using the MgO-based investment(Selevest CB, Selec). The cast and wrought titanium were treated with Au coating($ParaOne^{(R)}$., Gold Ion Sputter, Model PS-1200) and TiN coating(ATEC system, Korea) and the ultra low fusing dental porcelain was fused and fired onto the samples. Biaxial flection test was done on the fired samples and the porcelain was separated. The adhesion characteristics of porcelain and titanium after firing and the specimen surfaces before and after the porcelain fracture test were observed with SEM. The atomic percent of Si on all sample surfaces was comparatively analysed by EDS. In addition, the constituents of specimen surface layers after the porcelain fracture and the formed compound were evaluated by X-ray diffraction diagnosis. Result: The results of this study were obtained as follows : 1. The surface characteristics of cast and wrought titanium after surface treatment(Au, TiN, $Al_2O_3$ sandblasting) were similar and each cast and wrought titanium showed similar bonding characteristics. 2. Before and after the biaxial flection test, the highest atomic weight change of Si component was found in $Al_2O_3$ sandblasted wrought titanium(28.6at.% $\rightarrow$ 8.3at.%). On the other hand, the least change was seen in Au-Pd-In alloy(24.5at.% $\rightarrow$ 9.1at.%). 3. Much amount of Si components was uniformly distributed in Au and TiN coated titanium, but less amount of Si's was unevenly dispersed on Al2O3 sandblasting surfaces. 4. In X-ray diffraction diagnosis after porcelain debonding, we could see $Au_2Ti$ compound and TiN coating layers on Au and TiN coated surfaces and $TiO_2$, typical oxide of titanium, on all titanium surfaces. 5. Debonding of porcelain on cast and wrought titanium surface after the biaxial flection is considered as a result of adhesion deterioration between coating layers and titanium surfaces. We found that there are both adhesive failure and cohesive failure at the same time. Conclusion: These results showed that the titanium-ceramic adhesion could be improved by coating cast and wrought titanium surfaces with Au and TiN when making porcelain fused to metal crowns. In order to use porcelain fused to titanium clinically, it is considered that coating technique to enhance the bonding strength between coating kKlayers and titanium surfaces should be developed first.