• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.549-555
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• 1996

Diamond Like Carbon film is amorphous film which is considered to consist of three coordinate graphite structure and tetrahedron coordinate diamond structure. Its hardness, thermal conductivity and chemical stability are nearly to one of diamond. It is well known to become semi-conductor by doping of inpurity. In this study Diamond Like Carbon film was synthesized by Microwave Plasma CVD in the gas mixture of hydrogen-methan-nitrogen and doped of nitrogen on the single-crystal silicon or silica glass. The temperature of substrate and nitrogen concentration in the gas mixture had an effect on the bonding state, structural properties and conduction mechanism. The surface morphology was observed by Scanning Electron Microscope. The strucure was analyzed by laser Raman spectrometry. The bonding state was evaluated by electron spectroscopy. Diamond Like Carbon film synthesized was amorphous carbon containing the $sp^2$ and $sp^3$ carbon cluster. The number of $sp^2$ bonding increased as nitrogen concentration increased from 0 to 40 vol% in the feed gas at 1233K substrate temperature and at $7.4\times10^3$ Pa. Increase of nitrogen concentration made Diamond Like Carbon to be amorphous and the doze of nitragen could be controlled by nitrogen concentration of feed gas.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.53-61
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• 1999

Newley developed dentin bonding system which contains self-etching primer performed the removing of smear layer and etching procedure at once. So, it make possible more simple and shorter working time, the stronger bonding strength than conventional dentin bonding system. Cavities were prepared in the buccal and lingual surface of 30 extracted primary molars, and randomly assigned into three equal groups of 10 each. All cavities were filled with Z-100 composite resin following manufacturer's specifications after priming of three different dentin bonding system. Specimens stored for 7 days in 37 degree C water, thermocycled for 1000 cycles between 5 degree C and 55 degree C, immersed in 50% silvernitrate solution for 24 hours, and embedded in resin before being sectioned longitudinally. Data were analyzed by t-test and ANOVA. Mac-Bond II and Clearfil Linear-Bond II showed less microleakage at the occlusal and gingival margins compared to Scotchbond Multi Purpose. All dentin bonding systems showed significantly less microleakage at the occlusal margins compared to the gingival margins. But, there were no significantley difference between each group.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.423-430
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• 1993

The purpose of this study was to investigate the effect of ferric and ferric ions contained in phosphoric acid solution as a pretreatment solution on bonding of MMA/TBBO resin to dentin. Each of 1 % and 3 % ferric chloride. cupric chloride. cupric sulfate. and cupric nitrate was mixed into 10% phosphoric acid solution and pretreated dentin surface of bovine anterior teeth for 30 seconds followed- by water rinse and dry. Tensile bond strength was determined after bonding of pretreated dentin with MMA/TBBO resin by use of brush-on ;technique and storing for 24 hours in 3it distilled water. The amount of cupric ions adsorbed on pretreated dentin surface was detected by Wave-Dispersion X-ray microanalyzer for different groups of each pretreatment solution containing cupric salts. The pretreatment with cupric ions contained in 10% phosphoric acid solution was effective to increase bonding strength of MMA/TBBO resin to dentin but not in case of ferric ions. The pretreatment with 3 % cupric chloride and cupric nitrate both enhanced significant increase in bonding strength compared to the control group of 10% phosphoric acid solution(p<0.05). Cupric ions measured in pretreated dentin surface was higher in 3 % cupric chloride group than in 1% cupric chloride group, but couldn't find distinct relationship from the results of this experiment between the amount of adsorbed cupric ions according to the kind of cupric salts and the bonding strength value.

• Journal of information and communication convergence engineering
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• v.13 no.3
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• pp.172-179
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• 2015

Face-to-face (F2F) bonding in three-dimensional integrated circuits (3D ICs), compared with other bonding styles, is closer to commercialization because of its benefits in terms of density, yield, and cost. However, despite the benefits that F2F bonding expect to provide, it's physical nature has not been studied thoroughly. In this study, we, for the first time, extract cross-die (inter-die) parasitic elements from F2F bonds on the full-chip scale and compare them with the intra-die elements. This allows us to demonstrate the significant impact of field sharing across dies in F2F bonding on full-chip noise and critical path delay values. The baseline method used is the die-by-die method, where the parasitic elements of individual dies are extracted separately and the cross-die parasitic elements are ignored. Compared with this inaccurate method, which was the only method available until now, our first-of-its-kind holistic method corrects the delay error by 25.48% and the noise error by 175%.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.1
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• pp.2-9
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• 2003

The aluminum alloy which is light and has excellent thermal conductivity and iron base alloy that is remarkable heat-resistece and wear resistence properties were bonded together. The bond was created between a stationary and a rotating member by using the frictional heat generated between them while subjected to high normal forces on the interface of Al alloy and iron base alloy. The microstructure of the bonded interface of friction welding and the strength in the bonded interface formed under various bonding conditions were examined through TEM, SEM with EDX and triple bending test. In interface of bonding materials formed after various heat treatment, bonding strength was substantially different, resulting from formation of intermetallic compound or softening during annealing.

• Journal of Welding and Joining
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• v.29 no.6
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• pp.49-55
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• 2011

With the development of pre-painted steel sheets for automotive body application, a new joining method is required such as hybrid joining with combination of adhesive bonding and mechanical joining. The objective of this study is to investigate the effect of pre- and post-baking of adhesive bonding on failure mode and strength of hybrid joining of automotive steel sheets. Experiments show that the hybrid joining exhibits better bonding strength and displacement than conventional adhesive joining and mechanical fastening each. Comparison of pre- and post-baked hybrid joining results suggested that baking at $160^{\circ}C$ after mechanical joining was found to have higher joining properties than pre-baking condition. The prebaking condition changed its fracture mode from interfacial to button fracture. The changes in fracture mode with post-baking of hybrid joining was attributed to variation in neck thickness and undercut of joint.

• Journal of Global Scholars of Marketing Science
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• v.18 no.3
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• pp.115-132
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• 2008

Metal industry is one of the most representative heavy industries and the median sales volume of steel and nonferrous metal companies is over one billion dollars in the case America [Forbes 2006]. As seen in the recent business market situation, an increasing number of industrial manufacturers and suppliers are moving from adversarial to cooperative exchange attitudes that support the long-term relationships with their customers. This article presents the results of an empirical study of the antecedent factors of business relationships in metal industry of the United States. Commitment has been reviewed as a significant and critical variable in research on inter-organizational relationships (Hong et al. 2007, Kim et al. 2007). The future stability of any buyer-seller relationship depends upon the commitment made by the interactants to their relationship. Commitment, according to Dwyer et al. [1987], refers to "an implicit or explicit pledge of relational continuity between exchange partners" and they consider commitment to be the most advanced phase of buyer-seller exchange relationship. Bonds are made because the members need their partners in order to do something and this integration on a task basis can be either symbiotic or cooperative (Svensson 2008). To the extent that members seek the same or mutually supporting ends, there will be strong bonds among them. In other words, the principle that affects the strength of bonds is 'economy of decision making' [Turner 1970]. These bonds provide an important idea to study the causes of business long-term relationships in a sense that organizations can be mutually bonded by a common interest in the economic matters. Recently, the framework of structural bonding has been used to study the buyer-seller relationships in industrial marketing [Han and Sung 2008, Williams et al. 1998, Wilson 1995] in that this structural bonding is a crucial part of the theoretical justification for distinguishing discrete transactions from ongoing long-term relationships. The major antecedent factors of buyer commitment such as technology, CLalt, transaction-specific assets, and importance were identified and explored from the perspective of structural bonding. Research hypotheses were developed and tested by using survey data from the middle managers in the metal industry. H1: Level of technology of the relationship partner is positively related to the level of structural bonding between the buyer and the seller. H2: Comparison level of alternatives is negatively related to the level of structural bonding between the buyer and the seller. H3: Amount of the transaction-specific assets is positively related to the level of structural bonding between the buyer and the seller. H4: Importance of the relationship partner is positively related to the level of structural bonding between the buyer and the seller. H5: Level of structural bonding is positively related to the level of commitment to the relationship. To examine the major antecedent factors of industrial buyer's structural bonding and long-term relationship, questionnaire was prepared, mailed out to the sample of 400 purchasing managers of the US metal industry (SIC codes 33 and 34). After a follow-up request, 139 informants returnedthe questionnaires, resulting in a response rate of 35 percent. 134 responses were used in the final analysis after dropping 5 incomplete questionnaires. All measures were analyzed for reliability and validity following the guidelines offered by Churchill [1979] and Anderson and Gerbing [1988]., the results of fitting the model to the data indicated that the hypothesized model provides a good fit to the data. Goodness-of-fit index (GFI = 0.94) and other indices ( chi-square = 78.02 with p-value = 0.13, Adjusted GFI = 0.90, Normed Fit Index = 0.92) indicated that a major proportion of variances and covariances in the data was accounted for by the model as a whole, and all the parameter estimates showed statistical significance as evidenced by large t-values. All the factor loadings were significantly different from zero. On these grounds we judged the hypothesized model to be a reasonable representation of the data. The results from the present study suggest several implications for buyer-seller relationships. Theoretically, we attempted to conceptualize the antecedent factors of buyer-seller long-term relationships from the perspective of structural bondingin metal industry. The four underlying determinants (i.e. technology, CLalt, transaction-specific assets, and importance) of structural bonding are very critical variables of buyer-seller long-term business relationships. Our model of structural bonding makes an attempt to systematically examine the relationship between the antecedent factors of structural bonding and long-term commitment. Managerially, this research provides industrial purchasing managers with a good framework to assess the interaction processes with their partners and, ability to position their business relationships from the perspective of structural bonding. In other words, based on those underlying variables, industrial purchasing managers can determine the strength of the company's relationships with the key suppliers and its state of preparation to be a successful partner with those suppliers. Both the supplying and customer companies can also benefit by using the concept of 'structural bonding' and evaluating their relationships with key business partners from the structural point of view. In general, the results indicate that structural bonding gives a critical impact on the level of relationship commitment. Managerial implications and limitations of the study are also discussed.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.3
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• pp.47-61
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• 2012

parallel transmitting system with channel bonding method have been proposed to transmit mass content such as UHD(Ultra High Definition) in HFC(Hybrid Fiber Coaxial) networks. However, this system may lead to channel resource problem because the system needs many channels to transmit mass content. In this paper, we analyze three effective bandwidth approximation algorithms to use the bonding channel efficiently. These algorithms are the effective bandwidth of Gaussian approximation method algorithm proposed by Guerin, the effective bandwidth based on statistics of video frames proposed by Lee and the effective bandwidth based on Gaussian traffic proposed by Nagarajan. We also evaluate compatibility of algorithms to the mass broadcasting service. OPNET simulator is used to evaluate the performance of the algorithms. For accuracy of simulation, we make mass source from real HD broadcasting stream.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.6
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• pp.805-814
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• 2007

Statement of problem. Composite resin-veneered metal restorations can be used as an alternative to porcelain-fused-metal restorations. But, because of the relatively low bond strength of veneering composite to metal framework, various surface treatment methods have been introduced to improve the bond strength. Purpose. The object of this study was to compare the shear bond strength of different combinations of each of the two bonding systems and each of the two composite veneering resins to cp-Ti/Co-Cr alloy. Material and methods. Two resin bonding systems (metal conditioner containing MEPS monomer, tribochemical silicoating system) and two composite resins (Gradia, Sinfony) were tested on cp-Ti and Co-Cr alloy. Then, according to manufacturers' instructions, resin bonding systems and composite resins were applied. All test specimens were divided into four groups for each alloy; I) sandblast + Metal Primer II + Gradia (MG), II) sandblast + Metal Primer II + Sinfony (MS), III) Rocatec + Gradia (RG), IV) Rocatec + Sinfony (RS). The shear bond strength was determined using a universal testing machine and all data were statistically analyzed with Mann-Whitney test and Kruskal-Wallis test at the significance level of 0.05. Results. The mean (standard deviations) of shear bond strength according to the combinations of two bonding systems and two composite resins to cp-Ti arranged from 16.44 MPa to 17.07 MPa and the shear bond strength to Co-Cr alloy ranged from 16.26 MPa to 17.70 MPa. The result shows that the difference were not statistically significant. Conclusion. The shear bond strengths of composite resins to both cast cp-Ti and Co-Cr alloy were not significantly different between the metal conditioner and the tribochemical silicoating system. And no differences in bond strength were found between cp-Ti and Co-Cr alloy.

• The Journal of Advanced Prosthodontics
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• v.7 no.2
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• pp.85-92
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• 2015

PURPOSE. This study aimed to investigate the efficacy of cleaning solutions on saliva-contaminated zirconia in comparison to air-abrasion in terms of resin bonding. MATERIALS AND METHODS. For saliva-contaminated air-abraded zirconia, seven cleaning methods)-no contamination (NC), water-spray rinsing (WS), additional air-abrasion (AA), and cleaning with four solutions (Ivoclean [IC]; 1.0 wt% sodium dodecyl sulfate [SDS], 1.0 wt% hydrogen peroxide [HP], and 1.0 wt% sodium hypochlorite [SHC])-were tested. The zirconia surfaces for each group were characterized using various analytical techniques. Three bonded resin (Panavia F 2.0) cylinders (bonding area: $4.5mm^2$) were made on one zirconia disk specimen using the Ultradent jig method [four disks (12 cylinders)/group; a total of 28 disks]. After 5,000 thermocycling, all specimens were subjected to a shear bond strength test with a crosshead speed of 1.0 mm/minute. The fractured surfaces were observed using an optical and scanning electron microscope (SEM). RESULTS. Contact angle measurements showed that groups NC, AA, IC, and SHC had hydrophilic surfaces. The X-ray photoelectron spectroscopy (XPS) analysis showed similar elemental distributions between group AA and groups IC and SHC. Groups IC and SHC showed statistically similar bond strengths to groups NC and AA (P>.05), but not groups SDS and HP (P<.05). For groups WS, SDS, and HP, blister-like bubble formations were observed on the surfaces under SEM. CONCLUSION. Within the limitations of this in vitro study, some of the cleaning solutions (IC or SHC) were effective in removing saliva contamination and enhancing the resin bond strength.