• Economic and Environmental Geology
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• v.53 no.1
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• pp.71-85
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• 2020

To understand behavior of fault cores in the field of geotechnical and geological engineering, we present an investigation of the physical properties (breccia and clay contents, unit weight, porosity, and water content) and friction characteristics (internal friction angle and cohesion) of fault cores, in granitic, sedimentary, and volcanic rocks in South Korea. The breccia contents in the fault cores are positively correlated with unit weight and negatively correlated with clay content, porosity, and water content. The inter-quartile ranges of internal friction angles and cohesion calculated from direct shear tests are 16.7-38.1° and 2.5-25.3 kPa, respectively. The influence of physical properties on the friction characteristics of the fault cores was analyzed and showed that in all three rock types the internal friction angles are positively correlated with breccia content and unit weight, and negatively correlated with clay content, porosity, and water content. In contrast, the cohesions of the fault cores are negatively correlated with breccia content and unit weight, and positively correlated with clay content, porosity, and water content.

• Knowledge Management Research
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• v.4 no.2
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• pp.19-34
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• 2003

This paper analyzes 96 Korean companies to illustrate the relationship between the knowledge management strategies and task characteristics. Knowledge management strategies can be categorized as being codification- and personalization-oriented. Task characteristics are analyzed from the perspective of content-oriented, process-oriented, number of exceptions, and analyzability. These results illustrate how companies should align the knowledge management strategies with task characteristics. It is found that codification strategy is more likely to be associated with high content-oriented and high analyzability task, and personalization strategy is with high process-oriented task. The survey result confirms that managers should adjust knowledge management strategies in view of the characteristics of the task.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.128-136
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• 2012

The purposes of this study were to evaluate the level of PCK which middle school science teachers have on the concept of density and to analyze the characteristics of science teachers' content representation on the concept of density by their PCK level. For that purpose, 20 science teachers were selected and asked to answer the questionnaire on the eight aspects of CoRe. Results of this study indicated that the science teachers' PCK levels were low in general and evaluated as below average. The differences among the characteristics of science teachers' content representation by their PCK level were high in seven aspects of CoRe but the one aspect of the understanding of learner's preconception. These differences were analyzed and the patterns shown by the science teachers in eight aspects of CoRe were drawn in this study. It was also found that the characteristics drawn in eight aspects of content representation shown by the teachers whose PCK level was medium were close to those whose PCK level was low rather than high in most aspects of CoRe.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.825-831
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• 2013

The study examined the physico-chemical properties and sensory characteristics of injeolmi when sugar was substituted to sugar alcohol such as sorbitol and xylitol. The moisture content, crude protein content, crude fat content, crude ash content, energy value, redness, water activity, hardness, cohesiveness, gumminess, and chewiness were not significantly different between the control with sugar and treatments with the sugar alcohol group (p>0.05). The lowest sugar content of injeolmi was observed in the treatment with sorbitol (T1). The adhesiveness of control was higher than that in treatment with sugar alcohol (p<0.05), but control had the lowest springiness (p<0.05). Although the sensory characteristics on color, flavor, tenderness did not show any statistical significance, the sweetness and the overall acceptability were the best in control and T5 group, which replaced sugar to 100% xylitol (p<0.05). The results of this study show that substitution by xylitol improved quality characteristics in injeolmi.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.314-322
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• 2010

The effects of five colored soybean (blue, red, yellow, white, and black) varieties on the quality characteristics of soybean paste (Doenjang) were investigated for proximate composition, salt content, pH, color, organic acid content, amino acid content, and mineral content after 80 days of aging. Soybean paste (Doenjang) samples were divided into TDS (traditional Doenjang prepared with soybean) and TDM (traditional Doenjang prepared with mixed soybeans, kidney bean, black soybean, kind of small bean, sword bean, green bean, red bean, at a radio of 1:1:1:1:1(w/w)). Moisture content was 49.66% for TDM and 49.52% for TDM. Protein and salt contents of the TDS sample were higher than those of TDM. The "L" values of the TDB sample increased the aging period was decreased. In contrast, the "L" and "$\alpha$" values of TDM did not show any significant differences. The main organic acids detected were malic acid > lactic acid > tartaric acid in the TDS and TDM samples. Glutamic acid contents were 2.83 g/100 g for the TDS sample and 2.15 g/100 g for the TDM. The levels of K, Mg, and Ca of the TDS sample were higher than those of TDM. No significant difference occurred between TDS and TDM regarding their quality characteristics after 80 days of aging. Further studies needed include sensory evaluation and functionality of soybean paste made from mixed soybean materials.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.39-45
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• 2013

PURPOSES : The objective of this study is to evaluate the mechanical characteristics of castor oil based bio-polymer concrete for use of ultra thin overlays. METHODS : To evaluate the mechanical properties of bio-polymer concrete, the various laboratory tests including compressive, tensile, and flexural strength, and elongation tests were conducted on bio-polymer concrete specimens in this study. The mechanical characteristics of bio-polymer concretes were examined by changing the content of hardener and polymer binder to determine the optimum content for ultra-thin overlays. The bio-polymer concrete developed in this study was used for field trial test of the ultra-thin bridge deck pavement for verifying the workability and monitoring the long-term performance of materials. RESULTS : Test results showed that tensile and the flexural strength of bio-polymer concretes increase and the elongation of bio-polymer concrete decreases with increase of binder content. A field adhesive strength tests conducted on bridge deck pavement indicates the bio-polymer concrete has more than 2MPa of adhesive strength satisfy with the design criteria. CONCLUSIONS : The bio-polymer concrete with more than 20% content of castor oil was developed for ultra-thin overlays in this study. It is found from this study that the 35% of hardener content is most appropriate for maintaining the strength characteristics and flexibility.

• Journal of Digital Convergence
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• v.13 no.7
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• pp.47-55
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• 2015

In e-learning industry which represents the convergence of IT and education, the standard of e-learning content development cost has been calculated according to the guideline or standard of existing similar industries without considering the characteristics of the industry until today. The absence of contents development cost standard related to e-learning has been recognized as one of the most difficulties in e-learning industry. The calculation of the content development cost without reflecting the characteristics of e-learning industry has bad effects such as the degradation of content quality and development of e-learning industry, and the growth obstruction of them. This paper suggest a standard of development cost for e-learning content development considering the characteristics of e-learning industry. We analyse current problems and the characteristics in e-learning industry, and define the development cost standard. We propose the methodology for developing e-learning industry and for contributing quality improvement of e-learning content.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.22-27
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• 2010

This study was carried out to investigate the physicochemical characteristics of 3-year-old ginseng (for Samgyetang product) cultured by various seeding density in direct-sowing culture. Ginsengs were cultured by the seeding density, 275, 300, 330 352 and 396 seeds per Kan, $180{\times}90cm$ area. Survived rate (82.1%) were the highest in plot of 352 seeds sowed, length and leaf width were high in plot of 300 and 352 seeds. Root yield grain was increased with increase of the seeding density in direct-sowing culture except 352 seeds sowed. Average root weight and diameter were the highest in plot of 352 seeds sowed, 31.6 g and 18.4 mm, respectively. Crude saponin and each ginsenosides content were the highest in plot of 275 seeds sowed. Rg1 content was decreased, Rc and Rb2 content were increased with increase of the seeding density. Total soluble sugar content was the highest in plot of 330 seeds sowed and the lowest in plot of 396 seeds sowed, and oligo- and disaccaride content were high in plot of 330 and 352 seeds sowed. Reological characteristics of ginsengs cultivated according to various seeding density, hardness and springness were high and maximum fracture force was low with decrease of the seeding quantity.

• Korean journal of food and cookery science
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• v.31 no.5
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• pp.642-651
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• 2015

Asparagus, which was known to be a good source of dietary fiber and vitamins, has been reported to possess various medical actions such as antioxidant and blood pressure regulating effects. In order to examine the quality and antioxidant characteristics of asparagus, asparagus sponge cakes were prepared with different ratios of freeze dried asparagus powder (0%, 2%, 4%, 6%, 8%, w/w) in this study. With the increase of asparagus powder content in the sponge cakes, the specific gravity and baking loss increased while the dough yield decreased significantly. The moisture contents of the sponge cakes were not significantly different between the control and the cakes prepared with asparagus powder. The pH of the sponge cakes decreased significantly with increased amounts of asparagus powder. Furthermore, the pH of the sponge cake containing 8% asparagus powder was the lowest at 7.49. With the increase of asparagus powder content in the sponge cakes, lightness (L) and redness (a) decreased, whereas yellowness (b) increased. In texture analysis, the hardness and chewiness of the sponge cakes increased as the asparagus powder content increased, while the cohesiveness of the sponge cakes with asparagus powder decreased. Both total polyphenol content and DPPH (1,1-diphenyl-2-picryl hydrazyl) radical scavenging activity increased significantly with increased levels of asparagus powder content in the sponge cakes. In a sensory evaluation using a scale of 1-7, the sponge cake containing 8% asparagus powder had the lowest sensory preference scores. Therefore, the results of this study suggest that sponge cake prepared with 6% asparagus powder is the most appropriate product for quality characteristics.

• Journal of Ginseng Research
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• v.39 no.4
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• pp.371-375
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• 2015

Background: The current typical drying methods for red ginseng are sun drying and hot-air drying. The purpose of this study was to investigate drying characteristics of red ginseng by using far-infrared drying. Methods: The far-infrared drying tests on red ginseng were conducted at two drying stages: (1) high temperature for 24 h drying and (2) low temperature drying until the final moisture content was $13{\pm}0.5%$ (wet basis). The high temperature drying stage included three drying chamber temperature conditions of $60^{\circ}C$, $65^{\circ}C$, and $70^{\circ}C$. The low temperature drying stage was conducted at temperatures of $45^{\circ}C$ and $50^{\circ}C$. Drying characteristics were analyzed based on factors such as drying rate, color changes, energy consumption, and saponin content. The results were compared with those of the hot-air and sun drying methods. Results: The results revealed that increases in drying temperature caused a decrease in drying time and energy consumption for far-infrared drying. The saponin content decreased under all drying conditions after drying, the highest value (11.34 mg/g) was observed at drying conditions of $60{\sim}50^{\circ}C$. The sun drying condition showed the lowest color difference value when compared with far-infrared and hot-air drying. Conclusion: The far-infrared drying showed a faster drying rate, higher saponin content, lower color difference value, and a decrease in energy consumption than seen in hot-air drying.