• Journal of Power System Engineering
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• v.15 no.6
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• pp.59-66
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• 2011

This study was carried out the experimental and the analysis for process of carburizing and quenching, evaluated the reliability of mock-up. Carburizing of comer of rock gear was higher than body regardless of condition of eight processes, and the end of gear tooth was more highly distributed than root. Hardness of surface shows the maximum value and was decreased linear to depth direction. The result of analysis wasn't nearly the heat deformation. In mock-up, tooth flank increased 0.096%, thickness of tooth decreased 0.11% and body increased 0.11%. It had no trouble with assembly and operation like this. The mock-up of recliner for automobile was secured stability by four types of test.

• Journal of Biosystems Engineering
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• v.32 no.4
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• pp.207-214
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• 2007

Based on the profiles of cone index with depth, physical properties of hardpan in selected rice fields were measured and analyzed in the study. An error correction algorithm removing a random measurement error from raw CI profile data was introduced in the study. The properties of hardpan included the shape, the thickness and the rice root growing layer. The analysis of physical properties of hardpan in the rice fields showed that the type of hardpan could be classified into 6 categories. The thickness of hardpan ranged from 6 cm up to 41 cm and the average hardness of hardpan was analyzed to be from 1.1 MPa through 3.2 MPa in Cone index.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.5
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• pp.46-55
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• 2007

This study was carried out to analyze both the root structure and the fine root phytomass of the vertical and horizontal distribution of Zelkova serrata Makino. which was transplanted in the reclaimed land from the sea in Gwangyang, Jeonnam, South Korea. The base ground was reclaimed land from the sea. $Z_1$ of the planting ground was filled to a $100{\sim}150cm$ thickness with the improved soil instead of the reclaimed soil from the sea, $Z_2$ of the planting ground was covered to a $20{\sim}30cm$ thickness with the improved soil and $Z_3$ of the planting ground was mounded to 120cm thickness with the improved soil on the reclaimed land from the sea. In addition, $Z_4,\;Z_5\;and\;Z_6$ of the planting grounds were at the large-sized mound on the reclaimed land from the sea. $Z_4$ of the planting ground was located at the lowest level, $Z_5$ planting ground was located at the slope and $Z_6$ planting ground was located at the top of the large-sized mound. The large-sized mounds contain 3 layers, the base layer was reclaimed land from the sea and the second layer was mounded to a $200{\sim}300cm$ thickness with the desalinized soil from the sea on the base layers and the finally layers were mounded to a $80{\sim}120cm$ thickness with improved soil on the second layer. The planting grounds $Z_3,\;Z_4,\;Z_5\;and\;Z_6$ developed roots such as tap roots, lateral roots and heart roots. However, in $Z_1\;and\;Z_2$ roots development were inhibited. The fine-root phytomass of the 6 planting ground types was as follows: $113.5g\;DM/m^2$ for $Z_5$, $105.5g\;DM/m^2$ for $Z_4$, $88.3g\;DM/m^2$ for $Z_3$, $81.0g\;DM/m^2$ for $Z_6$, $73.0g\;DM/m^2$ for $Z_2$, $43.3g\;DM/m^2$ for $Z_1$. The vertical distribution of the fine root phytomass decreased from the upper to the deeper soil profiles in the 6 mound types. The fine root phytomass was $43.3{\sim}71.8%$ in a $0{\sim}20cm$ thickness of soil layer and it decreased according to the distance from the nearest trees. The root growth in the improved soil was better than in the reclaimed soil from the sea. However, root growth decreased more in the disturbed soils even though the planting grounds contained the improved soils. The retarded development of roots and the spatial distribution patterns of the fine root phytomass were closely connected to the reclaimed soil from the sea. In the disturbed soil, the soil hardness and alkalic cation($Na^+,\;K^+,\;Ca^{2+},\;Mg^{2+}$). were high and the soil water was lacking. We suggest that the construction of planting grounds and the improvement of bad soil are necessary for the proper and effective growth of landscaping plants.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.5
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• pp.345-349
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• 2000

$Al_2O_3/ZrO_2$eutectic fibers were grown by micro-pulling down technique and investigated their microstructure as a function of solidification rate. $Al_2O_3/ZrO_2$eutectic fibers 0.2~2 mm in diameter and 500 mm in length have been grown with a pulling rate of 0.1~15 mm/min. The eutectic microstructures changed as a function of fulling rate from rod-shaped to cellular shape containing some thin lamellar pattern via uniform lamellar structure. Typical lamellar thickness decreased from about 380 nm to 110 nm as the pulling rate increased from 1 mm/min to 15 mm/min. The interlamellar spacing fitted with the inverse-square-root dependence on pulling rate according to $\lambda$= $1{\times}v^{-1/2}$, where $\lambda$ has the dimension in $\mu\textrm{m}$ and v is $\mu\textrm{m}$/s. Hardness value reached 13.1 GPa at 15 mm/min of pulling rate and tensile strength 900 MPa at 10 mm/min were also increased as the interlamellar spacing decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.362-366
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• 2022

This study was conducted to find out the changes in the growth and yield of ginseng and the changes in the soil of direct-seeded ginseng fields after applying different compaction strengths. As a result of surface soil compactions, the topsoil hardness increases as the strength of treatment increases in the first year but topsoil hardness increased only by applying 30 kg weight of compaction in the second year. The germination rate was significantly higher (79.4% and 79.1% at 25 kg and 30 kg, respectively) in 1st year after the application of soil surface compactions. The longest plant was 35.7 cm in 4- years old ginseng in the control and the height was 26.9 cm and 26.5 cm in the soil surface compactions of 25 kg and 30 kg, respectively. In addition, the higher weight of ginseng roots of 31.3 g and 30.3 g were observed after applying 25 kg and 30 kg compaction treatment, and the lowest root weight of 25.6 g was in the control. Therefore, it is shown that after sowing, applying the weight of 25 kg to 30 kg for soil surface compaction is appropriate for better yield in direct seeded cultivation of ginseng at paddy fields.

• Journal of Welding and Joining
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• v.32 no.4
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• pp.26-33
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• 2014

The metallurgical and mechanical characteristics, toughness and corrosion resistance of dissimilar welds between super duplex stainless steel UNS S32750 and carbon steel ASTM A516Gr.70 have been evaluated. Three heat inputs of 21.12, 24.00, 26.88kJ/cm were employed to make joints of dissimilar metals with flux cored arc welding(FCAW). Based on microstructural examination, vermicular ferrite was formed in the first layer of weld at low heat input(21.12kJ/cm) and $Cr_{eq}/Ni_{eq}$ of 1.61 while acicular ferrite was formed in last layer of weld at high heat input(26.88kJ/cm) and $Cr_{eq}/Ni_{eq}$ of 1.72. Ferrite percentage in dissimilar welds was lowest in the first layer of weld regardless of heat inputs and it gradually increased in the second and third layers of weld. Heat affected zone showed higher hardness than the weld metal although reheated zone showed lower hardness than weld metal due to the formation of secondary austenite. Tensile strengths of dissimilar welds increased with heat input and there was 100MPa difference. The corrosion test by ferric chloride solution showed that carbon steel had poor corrosion resistance and pitting corrosion occurred in the first layer(root pass) of weld due to the presence of reheated zone where secondary austenite was formed. The salt spray test of carbon steel showed that the surface only corroded but the amount of weight loss was extremely low.

• Korean Journal of Human Ecology
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• v.22 no.5
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• pp.519-528
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• 2013

To evaluate the effect of Ulmus devidiana powder, muffins with Ulmus devidiana powder were made after supplementation with Ulmus devidiana powder(0, 5, 10 and 15%(all w/w)). Proximate composition of Ulmus devidiana powder was 7.49% moisture, 2.33% crude protein, 0.84% crude lipid, 66.74% carbohydrate, 14.09% crude fiber and 8.5% crude ash. The sample with 15% of Ulmus devidiana powder showed significantly lower volume compared to other groups. The symmetry of the sample with 5% of Ulmus devidiana powder was significantly lower than that of control group. No significant uniformity changes were observed. The height and baking loss rate of muffins with 15% Ulmus devidiana powder showed lower than that of other groups. But the weight of muffins with 15% Ulmus devidiana powder showed heavier than that of other groups. In color, L value and b value of muffins were decreased as the increase of the Ulmus devidiana powder. a value of muffins with Ulmus devidiana powder were higher than that of the control group. Hardness, gumminess and chewiness of groups with Ulmus devidiana powder were increased significantly as the increase of the amount of Ulmus devidiana powder. No changes of springness and cohesiveness were observed. Color, hardness, root odor and bitter taste intensity increased significantly with the increased addition of Ulmus devidiana powder. Acceptance of appearance, taste and overall acceptability of groups with 10% of Ulmus devidiana powder were significantly higher than that of the control group. As a result, 10% of Ulmus devidiana powder will be ideal to make muffins.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.1
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• pp.29-33
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• 2010

Titanium nitride (TiN) films were deposited on the polycarbonate substrate by using radio frequency (RF) magnetron sputtering without intentional substrate heating. After deposition, the films were bombarded with intense electron beam for 20 minutes. The intense electron irradiation impacts on the crystalline, hardness and surface roughness of the TiN films. The films irradiated with an electron beam of 300 eV show the small grains on the surface, while as deposited TiN films did not showany grains on the surface. Also the surface harness evaluated with micro indenter was increased up to 18 Gpa at electron energy of 900 eV after electron beam irradiation. In addition, surface root mean square (RMS) roughness of the films irradiated with intense electron beam affected strongly. The films irradiated by electron beam with 900 eV have the lowest roughness of 1.2 nm in this study.

• Journal of Ginseng Research
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• v.6 no.2
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• pp.154-161
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• 1982

To determine the effects of mulching with the hulls of rice on the growth of the ginseng plant and changes of its growing environment-soil moisture content. subterranccan temperature and soil hardness- were investigated under different light intensity such as 5%, 10%, 20%, and 30% light transmittance rate(LTR). The results obtained were as follows; 1. Soil moisture content under the shading was decreased as the increase of light intensity, whereas it was increased about 1.5% in each plot of LTR by the mulching. 2. Suberranccan temperature under the shading was increased as the increase of light intensity. It was decreased on a hot day by the mulching but increased on a cold day. 3. Soil hardness was decreased by the mulching. 4. Sprouting date of the ginseng plants was acclerated for 7 days and sprout periods were shortened for f days by mulching compared to the non-mulching treatment. 5. Missing plant rate was increased severely as the increase of light intensity more Than 20% LTR In the non-mulching plots but did not severe in the mulching plots. Missing plant rate was decreased remarkably by the mulching. The degree of decrease was larger as the increase 6f light intensity. 6. Root yield was increased in the mulching plots compared to the non$.$mulching plots. The degree of increase was larger as the increase of light intensity. The highest yield was obtained at 20% LTR with mulching.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.94-98
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• 1990

Seven varieties of soybeans (Paldal, Danyeob, Jangbaek, Baegun, Jangyeobkong and 2 cultivars of Local 1 and Local 2) were investigated to compare the germination properties and cooking rate. The growth rate of soybean sprout roots was slower for larger size of soybeans. A 100% of germination was obtained for Danyeobkong and Paldalkong. Local 1 and Local 2 were lowest, 47% and 31%, respectively in germination ratio. The hardness of cooked soybeans measured by the maximum cutting force of cotyledon showed that Local 2 was softer and Danyeobkong was harder than other varieties.