• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6432-6439
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• 2014

The NAUT (Non-contact Air coupled Ultrasonic Testing) technique is one of the ultrasonic testing methods that enables non-contact ultrasonic testing by compensating for the energy loss caused by the difference in acoustic impedance of air with an ultrasonic pulser receiver, PRE-AMP and high-sensitivity transducer. As the NAUT is performed in a state of steady ultrasonic transmission and reception, testing can be performed on materials of high or low temperatures or specimens with a rough surface or narrow part, which could not have been tested using the conventional contact-type testing technique. For this study, the internal defects of spot weld, which are often applied to auto parts, and CFRP parts, were tested to determine if it is practical to make the NAUT technique commercial. As the spot welded part had a high ultrasonic transmissivity, the result was shown as red. On the other hand, the part with an internal defect had a layer of air and low transmissivity, which was shown as blue. In addition, depending on the PRF (Pulse Repetition Frequency), an important factor that determines the measurement speed, the color sharpness showed differences. With the images obtained from CFRP specimens or an imaging device, it was possible to identify the shape, size and position of the internal defect within a short period of time. In this paper, it was confirmed in the above-described experiment that both internal defect detection and image processing of the defect could be possible using the NAUT technique. Moreover, it was possible to apply NAUT to the detection of internal defects in the spot welded parts or in CFRP parts, and commercialize its practical application to various fields.

• Asian Journal of Turfgrass Science
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• v.26 no.2
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• pp.135-139
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• 2012

Creeping bentgrass (Agrostis stolonifera) is one of the most popular turfgrasses for high-quality playing surface such as putting green on golf courses and athletic fields. Continues damage such as divot injury on creeping bentgrass is major issue to maintain golf course properly. Although plentiful researches to maximize divot resistance have been reported, minimal research has focused on relation between nitrogen (N) sources and divot resistance. The study was conducted to determine the effect of N source for turfgrass divot recovery and overall tee performance. Eleven fertilizer treatments as N sources were applied to creeping bentgrass 'Penncross'. Before the first application, divot injuries were simulated by removing a core of soil and turfgrass from established plots and backfilling with native soil. Data collection included turfgrass color and quality. N release speed did not influenced divot recovery. Frequency of urea application had no effects on divot recovery. Urea with split application had no difference with no treatment for divot recovery. Polyon product especially polyon mini (41-0-0) had the best performance for divot recovery and for maintaining better turfgrass quality. Overall, small particle size of slow-release N form would influence creeping bentgrasss to recover divot damage.

• Journal of Conservation Science
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• v.18 s.18
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• pp.63-74
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• 2006

All rock materials of the three storied stone pagoda in Seoakri were composed of light gray alkali granite with medium grained and developed with small mialolitic cavities. This stone pagoda is preserving almost archetype except the head part because there was repair work already. But, foundation, basement and roof rocks are serious state by microbial invasion such as lichens. Because there are tree and grass that cause direct effect to stone pagoda surrounding. Therefore, conservation treatment executed the primary dry cleaning and secondary wet cleaning treatment. Stone surface is partly not removed well such as lichens which part removed using cleansing device that use high temperature steam. Some treated part concrete and epoxy resin remove and retreatment with mixing talc and alkali granite powder to epoxy resin. Did color matching at mixing process of epoxy resin and fillers to properties with set the feel of a material. Also, drainage ditched to minimize inflow of rainwater fall from slope that is on the east of stone pagoda, tree and grass in stone pagoda surrounding wished to do remove and control occurrence of lichens hereafter minimizing moisture conteats.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.120-126
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• 2018

As a basic study for environment-friendly production of bacterial cellulose (BC) dressing with antimicrobial activity, we isolated and identified acetic acid bacteria which are resistant to silver ions and can biosynthesize silver nanoparticles. Furthermore, conditions of BC production by selected strain were also investigated. Strain G7 isolated from decayed grape skin was able to grow in the presence of 0.1 mM $AgNO_3$ which was identified as Acetobacter intermedius based on 16S rRNA gene analysis. BC production was the highest in a medium containing 2% glucose as a carbon source, 2% yeast extract as a nitrogen source, and 0.115% acetic acid as a cosubstrate. Structural properties of BC produced in optimal medium were studied using Fourier-transform infrared spectroscopy and X-ray diffractometer, and it was found that BC produced was cellulose type I that was the same as a typical native cellulose. When strain G7 was cultured in an optimal medium containing 0.1 mM $AgNO_3$, the color of the culture broth turned into reddish brown, indicating that silver nanoparticles were formed. As a result of UV-Vis spectral analysis of the culture, it was found that a unique absorption spectrum of silver nanoparticles at 425 nm was also observed. Scanning electron microscopic observations showed that silver nanoparticles were formed on the surface and pores of BC membrane.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3597-3601
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• 2013

In this study, a wet cleaning process, P II, using aqua-regia and sulfuric acid mixture with oxidant agent ($K_2S_2O_8$, $P_2O_5$, $KMnO_4$, $H_2O_2$ etc) is proposed to remove the metastable phase of graphite such as graphene and DLC for high quality synthetic diamonds. The process employed the conventional acid cleaning process (P I) as well as P I+P II to remove the graphite related impurities from the 200um-diamond powders synthesized at 7GPa-$1500^{\circ}C$-5minutes. The degree of cleaning after P I and P I+P II has been observed by naked-eye, optical microscopy, micro-Raman spectroscopy, and TGA-DTA. After P I+P II, the color of diamond became more vividly yellow with enhanced saturation with naked eye and optical microscopy analysis. Moreover, the disappearance of diamond-like-carbon (DLC) peak ($1440cm^{-1}$) observed by Raman spectroscopy confirmed the decrease in amount of remaining impurities. TGA-DTA results showed that the graphite impurities first started to dissolve at $770.91^{\circ}C$ after PI process. However, the pyrolysis started at $892.18^{\circ}C$ after P I+P II process because of the dissolution of pure diamonds. This result proved the effective dissolution of the metastable phase of graphite. We expect that the proposed P II process may enhance the quality of diamonds through effective removal of surface impurities.

• Journal of Korea Multimedia Society
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• v.10 no.7
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• pp.846-855
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• 2007

Significant feature extraction in cancer cell image analysis is an important process for grading cell carcinoma. In this study, we propose a method for 3D quantitative analysis of cell nuclei based upon digital image cytometry. First, we acquired volumetric renal cell carcinoma data for each grade using confocal laser scanning microscopy and segmented cell nuclei employing color features based upon a supervised teaming scheme. For 3D visualization, we used a contour-based method for surface rendering and a 3D texture mapping method for volume rendering. We then defined and extracted the 3D morphological features of cell nuclei. To evaluate what quantitative features of 3D analysis could contribute to diagnostic information, we analyzed the statistical significance of the extracted 3D features in each grade using an analysis of variance (ANOVA). Finally, we compared the 2D with the 3D features of cell nuclei and analyzed the correlations between them. We found statistically significant correlations between nuclear grade and 3D morphological features. The proposed method has potential for use as fundamental research in developing a new nuclear grading system for accurate diagnosis and prediction of prognosis.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.431-446
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• 2007

The purpose of this study is to review the taxonomical position of Phytolacca insularis Nakai based on morphological characters and ITS sequences. Phytolacca insularis was similar to P. acinosa in the stem shape, inflorescence, apocarpous, eight pistils, eight stamens, pink anther, and eight fruits. But the unique difference between P. insularis and P. acinosa was leaf size and pistil color. Phytolaccri insularis and P. acinosa have a similar sculpturing patterns as an foveolate and microscabrate in pollen, but they differed from P. americana in having a bigger foveolae size in sculpture pattern. Phytolacca insularis and P. acinosa were similar in the seed size but different from P. americana by having a small size of seed. The seed surface of P. insularis and P. acinosa was similar with a irregularly undulate shape, but its feature of P. americana differed in having the reticulate shape. Phytolacc a insularis had identical ITS sequences with P. acinosa. Phytolacca insularis and P. acinosa have a close relationship in the morphological characters and ITS sequences. The examinations of morphology and ITS sequences suggest that P. insularis be a form of P. acinosa although it has been formerly treated as a distinct species.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.2
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• pp.130-145
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• 2006

Objectives : The aim of this work is the approaching of properties-flavours theory and the making of morphological standard in Artemisiae herba. Methods : The properties-flavours theory were attempted with bibliographic method and various climate-information. The external-internal morphological standards were determined by using stereoscope and butanol series. Conclusions : The following is a list the conclusion of the approaching of properties-flavours theory and how to make the standard of morphological standard in artemisiae herba. 1. The significant analysis for the artemisiae herba as the properties-flavours theory, is a follow-up survey of the effect written in the official oriental medicine book 2. The other analytic methods according to the gathering time, processing or storing system or especially nature or growth environment(altitude, temperature,. the mean moisture, and the agronomical survey) by way of the explanation of properties-flavours theory appears so many insufficiency at the many cases. 3. In the case of artemisiae herba., there are 2 cases(Artemisia capillaris $T_{HUNB}$ and A. iwayomogi $K_{ITAMURA}$) in current and recently A. aruwa L. is substituted for artemisiae herba in circulation. 4. The external and internal characteristics according to the shape of original plant or herbal states, entirely correspond to all the official oriental medicine boo 5. According to the place of productiot the difference appeals. (1) A. capillatis $T_{HUNB}$. has leaves like a fine thread, and A. iwayomogi $K_{ITAMURA}$ has big and wide leaves, and shows some reddish color, and A. aruwa L. has narrow leaves, its section lines long vertically. (2) In the internal shapes, as the A. capillatis $T_{HUNB}$. leaves', upper epidermal cell wall shows relatively straight form, its all upper- lower epidemical cell wall has a stoma, and calcium rosette crystal is relatively few. As iwayomogi $K_{ITAMURA}$, all upper- lower epidermal cell wall is wavelike concave, and hypodermics has many stoma and many calcium rosette crystal. (3) In the internal shapes of A. aruwa L. the shape of leaves' epidermal cell is irregular and has so many non-glandular hair nad glandular hair on its surface.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.357-366
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• 2014

Based on fundamental properties and machining characteristics of Yellow poplar (Liriodendron tulipifera L.), it has well performance on machinability or workability, drying, and fine surface. Additionally, yellow poplar is light weight and has bright color with high performance of bending processing, so it could be used for furniture or artworks materials and wood-based panel materials. Recently, public attention has been focused on indoor air quality, and Ministry of environment drift more tight regulation on indoor air quality for an apartment house and public facility with the times. Construction materials has been assessed emission of volatile organic compounds (VOCs) and formaldehyde according to law (No.10789), so yellow poplar is also needed to assess these emission characteristics. Emission of VOC and aldehyde compounds from dry and green wood condition of yellow poplar were investigated with KS M 1998:2009. Based on results, more than 30 compounds were detected from yellow poplar, and lower NVOC (natural VOC) were emitted than AVOC (Anthropogenic VOC) and OVOC (other VOC). Formaldehyde emission was lower than $5{\mu}g/m^3$ and acetaldehyde, ketone, and propionaldehyde were detected from yellow poplar. From dry yellow poplar, m-Tolualdehyde ($33.6{\mu}g/m^3$) was additionally detected while no detection of propionaldehyde. After drying process, amount of ketone emission increased significantly. The unique smell of yellow poplar may not only come from emission of acetaldehyde and propionaldehyde.

• Current Optics and Photonics
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• v.4 no.1
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• pp.31-43
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• 2020

The feasibility of the application of terahertz electromagnetic waves in the diagnosis of prostate cancer was examined. Four samples of incomplete cancerous prostatic paraffin-embedded tissues were examined using terahertz spectral imaging (TPI) system and the results obtained by comparing the absorption coefficient and refractive index of prostate tumor, normal prostate tissue and smooth muscle from one of the paraffin tissue masses examined were reported. Three hundred and sixty cases of absorption coefficients from one of the paraffin tissues examined were used as raw data to classify these three tissues using the Principal Component Analysis (PCA) and Least Squares Support Vector Machine (LS-SVM). An excellent classification with an accuracy of 92.22% in the prediction set was achieved. Using the distribution information of THz reflection signal intensity from sample surface and absorption coefficient of the sample, an attempt was made to use the TPI system to identify the boundaries of the different tissues involved (prostate tumors, normal and smooth muscles). The location of three identified regions in the terahertz images (frequency domain slice absorption coefficient imaging, 1.2 THz) were compared with those obtained from the histopathologic examination. The tissue tumor region had a distinctively visible color and could well be distinguished from other tissue regions in terahertz images. Results indicate that a THz spectroscopy imaging system can be efficiently used in conjunction with the proposed advanced computer-based mathematical analysis method to identify tumor regions in the paraffin tissue mass of prostate cancer.