• Economic and Environmental Geology
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• v.37 no.3
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• pp.355-364
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• 2004

A study on the weathering grade classification has been performed for granite and granite gneiss in Korea. The qualitative classification criteria of weathering were reviewed and then modified with field studies for the weathered rock masses. The thin section observations and XRD analyses for the different weathering grades rock samples showed the petrographical and petrophysical difference with respect to the weathering : the proportion of weathering-resistant minerals suck at quartz and orthoclase has a tendency to increase with the development of weathering, but that of weathering-sensible minerals such as anorthite and biotite is decreased. The ranges of physical and mechanical rock properties for different weathering grades were obtained from the laboratory rock tests and field tests for the studied rocks. And then, along with $RDI_{sq}$(Fookes et al., 1988), the weathering index $I_{a}$, (Woo, 2003) has been developed in this study to demarcate the weathering grade. Those two indices rely mainly on the water absorption ratio of rock and on the different rock strength. The range of these weathering indices have been determined with the physical and mechanical rock properties that can be obtained from simple field or laboratory tests in 4 grades $I_{a}$＞ 7 for F, 3.5 ＜ $I_{a}$ ＜ 10 for SW, 1.0 $I_{a}$＜ 6.0 for MW and $I_{a}$＜ 2.5 for HW. Consequently, the weathering index could be utilized to classify quantitatively the rock weathering grade, especially for the studied granites and the granite gneiss in Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.921-927
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• 2015

The aim of this study was to investigate the effect of die temperature and repeated extrusion on physical properties of extruded white ginseng (EWG). The die temperature was adjusted to 100, 120, and $140^{\circ}C$, and extrusion was repeated under the same conditions with their corresponding samples. Specific mechanical energy input decreased as die temperature increased during extrusions. The secondary extruded white ginseng (SEWG) at a die temperature of $120^{\circ}C$ showed a higher expansion index than other extrudates. Elevation of both die temperature and repeated extrusion increased the specific length of extrudates. The highest apparent elastic modulus, breaking strength, and water solubility index obtained from SEWG at a die temperature of $100^{\circ}C$ were $7.53{\times}10^8N/m^2$, $7.49{\times}10^5N/m^2$, and 39.02%, respectively. When die temperature increased, water absorption index (WAI) decreased. The WAI of SEWG was higher than that of EWG. In conclusion, repeated extrusion affected physical properties of white ginseng and could be applied to produce improved quality of ginseng products.

• The korean journal of orthodontics
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• v.39 no.4
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• pp.213-224
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• 2009

Objective: The aim of this study was to find out whether Er:YAG laser can aid in debonding ceramic brackets, and to see what kind of method will be the most appropriate for debonding. Methods: One hundred and ninety teeth, monocrystalline brackets ($MISO^{TM}$, HT, Ansan-Si, Korea), polycrystalline brackets ($Transcend^{TM}$ series 6000, 3M Untek, Monrovia, CA, USA) and the KEY Laser3 (KavoDental, Biberach, Germany) were used. Experimental groups were classified according to the type of ceramic brackets, and the amount of laser energy (0, 140, 300, 450, 600 mJ). After applying laser on the bracket at two points at 1 pulse each, the shear bond strength was measured. The effect of heat caused by laser was measured at the enamel beneath the bracket and pulp chamber. After measuring the shear bond strength, adhesive residue was evaluated and enamel surface was investigated using SEM. Results: All ceramic bracket groups showed a significant decrease in shear bond strength as the laser energy increased. The greatest average temperature change was $3.78^{\circ}C$ on the enamel beneath the bracket and $0.9^{\circ}C$ on the pulp chamber. Through SEM, crater shape holes caused by the laser was seen on the enamel and adhesive surfaces. Conclusions: If laser is applied on ceramic brackets for debonding, 300 - 450 mJ of laser energy will be safe and efficient for monocrystalline brackets ($MISO^{TM}$), and about 450 mJ for polycrystalline brackets ($Transcend^{TM}$ series 6000).

• The korean journal of orthodontics
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• v.25 no.2 s.49
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• pp.223-233
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• 1995

The purpose of this study was to evaluate the effects of surface conditioning with $10\%$ polyacrylic acid, etching with $38\%$ phosphoric acid, and polishing with a slurry of pumice on shear bond strengths of light-cured glass ionomer cement, chemically cured glass ionomer cement, and a composite resin to enamel, and to observe the failure patterns of bracket bondings. Shear bond strengths of glass ionomer cements were compared with that of a composite resin. Metal brackets were bonded on the extracted human bicuspids after enamel surface treatments, and samples were immersed in the $37^{\circ}C$ distilled water bath, and shear bond strengths of glass ionomer cements and a composite resin were measured on the Instron machine after 24hrs passed, and the deboned samples were measured in respect of adhesive remnant index. Scanning electron micrographs were taken of enamel surfaces after various treatments. The data were evaluated and tested by ANOVA and Duncan's multiple range test, and those results were as follows. 1. Shear bond strength of light-cured glass ionomer cement showed statistically higher than that of chemically cured glass ionomer cement. 2. Shear bond strengths of light-cured and chemically cured glass ionomer cements to enamel treated with $10\%$ polyacrylic acid and $38\%$ phosphoric acid showed statistically higher than those with a slurry of pumice. 3. According to scanning electron micrographs, enamel surface conditioned with $10\%$ polyacrylic acid is slightly etched and cleaned, that etched with $38\%$ phosphoric acid is severely etched, and that polished with a slurry of pumice is irregulary scretched and not completely cleaned. 4. After debonding, light-cured glass ionomer cement to enamel treated with $10\%$ polyacrylic acid showed less residual materials on the enamel solace than composite resin to enamel etched with $38\%$ phosphoric acid. 5. There was no significant difference in the shear bond strength of light-cured glass ionomer cement to enamel treated with $10\%$ polyacrylic acid and that of composite resin to enamel etched with $38\%$ Phosphoric acid.

• Journal of Chest Surgery
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• v.43 no.3
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• pp.235-245
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• 2010

Background: Our goal was to evaluate anti-calcification effects of decellularization and diverse fixing methods including preincubation of the bovine pericardium with ethanol. We also assessed changes in mechanical properties. Material and Method: Harvested bovine pericardium was decellularized with 0.25% sodim dodecysulfate and then treated with 5 methods of fixation: (1) 0.5% glutaraldehyde (GA) for 14 days, (2) 0.5% GA for 5 days, 2% GA for 2 days and 0.25% GA for 7 days, (3) 0.5% GA for 5 days, 2% GA for 2 days, 0.25% GA for 7 days, and then 70% ethanol for 2 days, (4) 0.5% GA for 5 days, a mixture of 2% GA and 70% ethanol for 2 days, and 0.25% GA for 7 days, (5) 0.5% GA for 5 days, a mixture of 2% GA, 65% ethanol, and 5% octanediol for 2 days and then 0.25% GA for 7 days. All treated bovine pericardia were tested for histological variables, lipid content, and mechanical properties including tensile strength and thermal stability. A total 10 kinds of differently treated bovine pericardia were implanted into rat subdermis and harvested 8 weeks later. Harvested pericardia were evaluated for calcium content. Result: No protein denaturation was observed microscopically after decellularization. There was a 32% mean decrease in tensile strength index after decellularization in the bovine pericardium group fixed. Octanediol preincubation attenuated the decrease in tensile strength and maintained thermal stability. TG and cholesterol were not affected by decellularization but were decreased by organic solvent. Calcium content was decreased after decellularization, and organic solvent preincubation decreased calcification in the non-decellularized bovine pericardium group. Conclusion: Decellularization and organic solvent preincubation have anti-calcification effects but decellularization may cause mechanical instability. A method of decellularization and fixation that does not cause damage to matrices will be needed for evaluation of the next step in using tissue-engineering for replacement of cardiac valves.

• 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 Korean Medicine Rehabilitation
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• v.15 no.1
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• pp.109-126
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• 2005

Objectives : This study is to examine the influence of exorcise program to body shape and body composition of women. Exercise program is composed muscular resistance exercise and aerobic exorcise with 70min/time, 5day/week for 4weeks and designed for the reinforcement of muscular strength and the decease the decrease of obesity. Methods : The subjects of this study are 26 females who are from twenty until thirty-nine years old and are divided into two groups according to Obese Rate. normal weight group is 18 females under a BMI of 23 and overweight group is 8 females over a BMI of 23. we measured body compositon and body shape with body composition analyzer(inbody 3.0) measured body compositions are body weight, Lean body mass, base metabolic rate, body fat, %body fat, waist hip ratio, body mass index. measured 6body shade are upper arm circumference, chest circumference, waist circumference, hip circumference, thigh circumference. the measurements had been taken before exercise of each group, after 4 weeks, after 8 weeks, after 12 weeks. Body compositon and body shape of the measured data were analyzed by two-way repeated ANOVA followed by Dunnett's Post hoc test using SPSS. Differences were considered significant at p<0.05. Results and Conclusions : The weight was reduced at a significant level in overweight group after 4 weeks. Body fat percent was reduced at a significant level in normal group alter 4 weeks and overweight group after 8 weeks. Waist-hip ratio was reduced at a significant level in normal and overweight group after 4 weeks. Lean body mass and body metabolic rate were reduced but did not satisfy statistical significance. Circumference of all body parts showed an decrease after 12 weeks exercise program. Upper Arm, Chest, Waist, Hip Circumference were reduced at a significant level in overweight group after 4 weeks, but In normal group only Waist Circumference was reduced at a significant level after 4 weeks. Aerobic and Circuit weight training for 12 weeks reduced body weight and body fat percent, waist circumstance statistically significant without loss of lean body mass and body metabolic rate. Also these change was more effective in overweight group than in normal group.

• Korean Journal of Poultry Science
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• v.29 no.1
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• pp.7-12
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• 2002

This study was conducted to investigate the effects of feeding germanium colloid(GC) on the egg quality and immune response in 1aying hens. One hundred forty four layers, 32-wk-old ISA Brown, were used in a 40-d experimental assay with a 7-d adjustment Period. Dietary treatments included 1) control (basal diet; CON), 2) 0.5ppm GC (basal diet + 0.Sppm germanium), 3) 1.0ppm GC (basal diet + 1.0 ppm germanium) . For overall Period, hen-day e99 Production tended to be increased as the concentration of GC in the diets was increased with significant difference (linear effect, p<0.01) . Laying hens fed 0.5ppm GC diet were significantly (P<0.01) lower in egg shell breaking strength than laying hens fed CON or 1.0 ppm GC diets. Egg shell thickness and yolk color were not influenced by GC supplementation. Laying hens fed 1.0ppm GC diet were h19her in egg yolk Index than laying hens fed CON and 0.5ppm GC diets with significant difference (quadratic effect, p<0.02) . As adding level of germanium colloid increased in the diets, the total serum cholesterol and triglyceride tended to be decreased. However, the effect of GC supplementation did not show significant in the levers of total serum cholesterol and triglyceride. Also, HDL- and LDL+VLDL-cholesterol in serum were not statistically different among the treatments. Red blood cell and white blood cell count in blood tended to be increased as the concentration of GC in the diets was increased with significant difference (P<0.01) . Hematocrit concentration in blood was successfully Increased by supplementation of GC (P<0.01) . In conclusion, although egg quality was not influenced by GC supplementation, supplementing GC Improved Immune status in laying hens.

• The Journal of Engineering Geology
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• v.24 no.2
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• pp.247-260
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• 2014

Rock masses at the site for the $2^{nd}$ step construction of the KAERI Underground Research Tunnel (KURT) are divided into six units to establish a rock mechanics model that is dependent on the geological characteristics and degree of joint development. The site primarily consists of three granitic units (G1, G2, and G3), two dykes (D1 and D3), and a fault zone of poor rock mass quality (F3). The F3 unit crosses the tunnel at the beginning of the site of $2^{nd}$ step construction. The rock masses of each unit are classified by RMR (Rock Mass Rating), Q-system, and RMi (Rock Mass Index), all based on borehole logging data. The deformation modulus, rock mass strength, cohesion, and friction angle for each unit are calculated using established empirical relationships. The representative rock mass classification and geotechnical parameters for the rock mass units are established, and a rock mechanics model for the site is proposed, which will be useful in the design and stability analysis of the $2^{nd}$ step construction of KURT.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.393-398
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• 2013

Lodging in the direct seeded rice cultivation on flooded paddy is being severe problem due to the lower production and grain quality at ripening stage. This study was conducted to examine the effect of Iprobenfos-metconazole (IPM) treated 50, 40 and 30 days before heading respectively as a plant regulator to reduce the lodging at ripening stage of direct seeding rice cultivation. The culm length treated with IPM, especially the 4th culm internode, was shortened more than with untreated plot, and the most effective time was at 30 days before heading. At 20 days after heading the flag leaves colour showed more greening than in the untreated leaves and the plot with IPM treatment was to be maintained longer compared to the control plot. The Nitrogen concentration of leaves with IPM was lower than in the control plot, and $SiO_2$ contents were higher than in the untreated plot and $SiO_2/N$ ratio was increased more in the IPM plot than in the control plot. The breaking strength of 3rd and 4th culm internode with IPM treatment was higher than in the untreated plot, and the lodging index was reduced in the IPM plot significantly and the field lodging also was reduced. As the results the rice production in the IPM plot was increased more due to be higher ripening ratio and seed grain weight compared to the untreated plot to be occurred the field lodging.