• Geomechanics and Engineering
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• v.28 no.6
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• pp.547-557
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• 2022

Dune sands are poorly graded collapsible soils lacking fines. This experimental study explored the technical feasibility of sustainable invigoration of fine waste materials to improve the geotechnical properties of dune sand. The fine waste considered in this study is fine marble waste. The fine waste powder was mixed with dune sand at different contents (5, 10,15, 20, 25, 50%), where the gradation, void ratio, compaction, and shear strength characteristics were assessed for each fine marble waste -dune sand blend. The geotechnical properties of the dune sand-fine marble waste mix delineated in this study reveal the enhancement in compaction and gradation characteristics of dune sand. According to the results, the binary mixture of dune sand with 20% of fine marble waste gives the highest maximum dry density and results in shear strength improvement. In addition, a numerical study is conducted for the practical application of the binary mix in the field and tested for an isolated shallow foundation. The elemental analysis of the fine marble waste confirms that the material is non-contaminated and can be employed for engineering applications. Furthermore, the numerical study elucidated that the shallow surface replacement of the site with the dune sand mixed with 20% fine marble waste gives optimal performance in terms of stress generation and settlement behavior of an isolated footing. For a sustainable mechanical performance of the fine marble waste mixed sand, an optimum dose of 20% fine marble waste is recommended, and some correlations are proposed. Thus, for improving dune sand's geotechnical characteristics, the addition of fine marble waste to the dune sand is an environment-friendly solution.

• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.286-298
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• 1995

This study was carried out to investigate the effect of forest soil acidification on the distribution of exchangeable cations($Ca^{2+}$, $Mg^{2+}$, $Al^{3+}$) and heavy metals(Cu, Zn, Mn, Pb, Cd) in soil, and to understand the relation of the soil chemical properties and the distribution of nutrients and hear metals in fine root and foliage. The results through survey on the long - term change of soil pH and the contents of nutrient and heavy metal in soil, fine root and foliage by 2 sites near Ulsan - Onsan industrial estate and 2 sites in limited development district are summarized as follows : 1. The average forest soil pH(A horizon) in Ulsan had been proceeded down to 3.73 in deciduous forest and 3.86 in coniferous forest in 1994 from 4.45 and 4.78 in 1987, respectively, which indicated serious soil acidification. As comparing soil pH among sites, Dongcheon coniferous forest(pH 4.57) in limited development district showed the highest values and Dangwol deciduous forest(pH 3.19) near Onsan industrial estate showed the lowest values in 1994. 2. Contents of exchangeable calcium in forest soils of limited development district where showed much higher soil pH than industrial estate were 3.5 times more in deciduous forest soil and 11 times more in coniferous forest soil than in industrial estate, and contents of exchangeable magnesium were also 4.5 and 5 times more in limited development district than in industrial estate, respectively. However contents of exchangeable aluminium which had been supposed more in forest soil of industrial estate were more in limited development district. 3. Contents of calcium and magnesium in fine root of deciduous trees(A hirsuta. Q. acutissima) were 3.6 and 1.7 times more in limited development district than in industrial estate, respectively, and those of coniferous trees(P. rigida, P. thunbergii) were 4.6 and 1.5 times more in Limited development district than in industrial estate, respectively. Also contents of calcium and magnesium in foliage of deciduous trees were 1.1 and 2.2 times more in limited development district than in industrial estate, respectively, and those of coniferous trees were 1.8 and 3.3 times more in limited development district, respectively. And contents of aluminium in fine root and foliage were nearly as same as in soil. 4. Ca/Al molar ratios in soil and fine root, which could be related with the dgree of soil acidification and Al toxicity on trees, were Less than 1 in all sites except Dongcheon, suggesting that the soil and fine root in the sites have high sensitivity to soil acidification and the decrease in nutrient uptake and root enlargement. The Ca/Al molar ratios in soil and fine root in coniferous forest were highly correlated with the soil pH one another. 5. Contents of Cu, Zn and Pb in soil, fine root and foliage were more in industrial estate than in limited development district in both deciduous and coniferous forests, however, oppositely contents of Mn and Cd in soil were more in limited development district than in industrial estate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.2
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• pp.159-164
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• 2009

The difference of ginsenosides content according to placement of ginseng planting (line) under shading net in 5-year-old ginseng roots were examined. The total saponin ($Rb_1$, $Rb_2$, Rc, Rd, Re, and $Rg_1$) contents were 15.01 mg/g and 21.79 mg/g in the main roots, 35.93 mg/g and 43.32 mg/g in the lateral roots, 87.85 mg/g and 105.51 mg/g in the fine roots for the front $1st{\sim}2nd$ lines in Yunpoong and Landrace variety (purple-stem variant), respectively. In the middle $3rd{\sim}5th$ lines the total saponin contents were 18.73 mg/g and 23.19 mg/g in the main roots, 44.92 mg/g and 43.50 mg/g in the lateral roots, 92.97 mg/g and 110.70 mg/g in the fine roots in Yunpoong and Landrace variety, respectively. In the rear $6th{\sim}7th$ lines the total saponin contents were 21.88 mg/g and 26.68 mg/g in the main roots, 38.41 mg/g and 44.89 mg/g in the lateral roots, 101.03 mg/g and 107.06 mg/g in the fine roots in Yunpoong and Landrace variety, respectively. The differences in total and individual ginsenosides content in the main, lateral and fine roots among the lines were not significant but total ginsenosides contents in the main roots were different in case of Yunpoong variety. The ratios of protopanaxadiol (PD) type saponin to protopanaxatriol (PT) type saponin in roots were lower in the front lines compared to the middle and rear lines and the ratios were significantly different among the parts of roots.

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.05a
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• pp.290-291
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• 2005

• Ocean and Polar Research
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• v.42 no.3
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• pp.249-261
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• 2020

This study details grain-size distributions (GSDs) of carbonate and biogenic opal fractions of the sediments retrieved from the South Korea Plateau in the East Sea and draws paleocanographic implications from them. The opal-fraction GSDs show fine modes of 10.3 ㎛ and coarse modes of 102.5 ㎛ on average. The fine-mode grains of opal fractions mainly consist of small diatoms and radiolarians including their broken frustules, while the coarse-mode grains are mostly comprised of large warm-water diatoms and radiolarians. Significant positive correlation between opal contents and abundances of the coarse-mode GSDs in the total GSDs suggests that the abundances of the coarse-mode GSDs were controlled by the increased surface productivity of warm-water diatoms during interglacial stages. The carbonate-fraction GSDs show fine modes of 2.4 ㎛ and coarse modes of 99.1 ㎛ on average. The fine-mode grains mainly consist of coccolithophores, while the coarse-mode grains are mostly comprised of intact or broken planktonic foraminifera. The abundances of coarse-mode and fine-mode GSDs were not correlated with carbonate contents, suggesting a complex control exerted by both the degree of carbonate dissolution and the productivity of coccolithophores on the carbonate-fraction GSDs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.165-179
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• 2006

Food habits of the gavelin goby Acanthogobius hasta and the fine spot goby Chaeturichtys stigmatias populations were investigated in the Jangbong tidal flat near Incheon, Korea. Samples were taken monthly from November 1999 to January 2001. The gut contents of 248 gavelin gobies and 139 fine spot gobies were analyzed. The diet of the gavelin goby was dominated by the gammaridean amphipod Chitinomandibulum emargicoxa, the crabs Macrophthalmus japonicus and Ilyoplax pingi, the shrimp Exopalaemon carinicauda, the bivalve Raetellops pulchella and the macro-algae Porphyra tenera. On the other hand, the fine spot goby mainly feed on the shrimps Crangon affinis, Latreutes mucronatus, E. carinicauda and Alpheus japonicus, the gammaridean amphipods C. emargicoxa and Synchelidium miraculum, and the bivalve R. pulchella. A comparison between frequencies of occurrence and abundance of food items in the gut showed that crustaceans (gammaridean amphipods, crabs and shrimps) and bivalves were important foods for the two gobies. However, the main components of the gut contents were different between two species, though this was probably due to differences in spatial distribution patterns of gobies and their prey items. In conclusion, both the gavelin goby and the fine spot goby, despite being the related species and co-inhabiting the similar part of the tidal flat, had quite distinct food habits and low dietary overlap (Schoener's index: 0.4). These indicated that the two gobies are or were partitioning resources in space and time for maximum uitilization of available food.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.5
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• pp.83-91
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• 2017

Recently, ground subsidence frequently occurs in downtown area. The major causes of the subsidence on the subsurface were the damages of the water supply and sewer pipelines and excavation works in adjacent areas, etc. Because of these various factors, it is not easy to analyze the tendency of occurrence of ground subsidence. The purpose of this study is to clarify the effect of ground subsidence by the change of the fine particle content and ground water level and to establish the ground subsidence mechanism. In this study, a model soil-box was manufactured to simulate the failure of the old sewer pipe which is one of the causes on ground subsidence. And a model test was conducted to investigate the effects of fine contents and ground water level on the cavity occurrence. From the test results, firstly the higher the ground water level, the faster the primary cavity is formed as the seepage stress increases. As a result, the secondary cavity and the ground subsidence rapidly progress due to the relaxation of the surrounding ground. The total amount of discharged soil was decreased as the fine content increased.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.290-297
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• 2016

This study analyzed the features of the nodules requiring a fine needle aspiration, which were found in thyroid ultrasonography of the employee health check-up examinees. Based on the fine needle aspiration results, over 1 cm nodules or those implying malignancy on the ultrasonography were categorized into the 1st group. Whereas, regardless of the size the fine needle aspiration results implying malignancy on the ultrasonography were categorized into the 2nd group. In the 1st group, 15.8% were malignant, and in the 2nd group, 28% were malignant. The findings implying malignancy were statistically significant. However, even though the nodules were larger than 1 cm, when the nodules were not accompanied by a high risk factor and showed a spongiform structure in the ultrasonographic results, most of them were benign, and a fine needle aspiration was not required. The ultrasonographic findings are important rationales in making a decision on whether or not a fine needle aspiration is required for thyroid nodules. Currently, the fine needle aspiration for thyroid nodules is commonly performed when the size of the nodule is larger than 1 cm, even though it has a spongiform structure, to relieve the patient's anxiety. However, if ultrasonographic findings of thyroid are correctly understood in differentiating malignant from benign nodules, unnecessary fine needle aspiration can be avoided.

• Korean Journal of Medicinal Crop Science
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• v.22 no.1
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• pp.23-31
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• 2014

This study was carried out to investigate change of ginsenoside contents in red and fresh ginseng according to root part and age by hydrolysis. Neutral total ginsenoside contents by hydrolysis in 6-year main root and lateral root were significantly increased than those by non-hydrolysis, as 41.6 and 32.8%, respectively. However, there was no significant difference in red ginseng. In fresh ginseng, ginsenoside contents of the protopanaxatriol group such as Re, Rf, $Rg_1$, $Rg_2$, and $Rh_1$ were not significantly different, but $Rb_1$, $Rb_2$, $Rb_3$, Rc, and Rd showed significant difference. The increase rate of neutral total ginsenoside content by hydrolysis was higher in epidermis-cortex than stele. Also, the neutral total ginsenoside content was fine root > rhizome > lateral root > main root, respectively. While there was no tendency towards the increase of ginsenoside by hydrolysis with the increase of root age in fine root and rhizome, there was significant decrease in main root and lateral root.

• The Journal of the Korea Contents Association
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• v.6 no.5
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• pp.76-84
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• 2006

When a human-being gets a wrong perception about any object is a misunderstanding and what they feel through sense of sight is an optical illusion. The study about those illusions have been given out to not only the fields of fine art, design, and animation but also psychology First, this paper puts in order an op art, influenced in fine art and design, and animation using persistence of vision, relating an optical illusion. Second, it analyses the theory of art form using an optical illusion about brightness, saturation, contrast and luminosity of color. Finally, it makes an experiment of standard of perception on students. The study of art form using an optical illusion is another way to represent fine art comparisons and visual image including animation.