• Title/Summary/Keyword: surface extraction

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Development of an Extraction Method of Cortical Surfaces from MR Images for Improvement in Efficiency and Accuracy (효율성과 정확도 향상을 위한 MR 영상에서의 뇌 외곽선 추출 기법 개발)

  • An, Kwang-Ok;Jung, Hyun-Kyo
    • Journal of Biomedical Engineering Research
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    • v.28 no.4
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    • pp.549-555
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    • 2007
  • In order to study cortical properties in human, it is necessary to obtain an accurate and explicit representation of the cortical surface in individual subjects. Among many approaches, surface-based method that reconstructs a 3-D model from contour lines on cross-section images is widely used. In general, however, medical brain imaging has some problems such as the complexity of the images, non-linear gain artifacts and so on. Due these limitations, therefore, extracting anatomical structures from imaging data is very a complicated and time-consuming task. In this paper, we present an improved method for extracting contour lines of cortical surface from magnetic resonance images that simplifies procedures of a conventional method. The conventional method obtains contour lines through thinning and chain code process. On the other hand, the proposed method can extract contour lines from comparison between boundary data and labeling image without supplementary processes. The usefulness of the proposed method has been verified using brain image.

A Region Based Approach to Surface Segmentation using LIDAR Data and Images

  • Moon, Ji-Young;Lee, Im-Pyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.6_1
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    • pp.575-583
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    • 2007
  • Surface segmentation aims to represent the terrain as a set of bounded and analytically defined surface patches. Many previous segmentation methods have been developed to extract planar patches from LIDAR data for building extraction. However, most of them were not fully satisfactory for more general applications in terms of the degree of automation and the quality of the segmentation results. This is mainly caused from the limited information derived from LIDAR data. The purpose of this study is thus to develop an automatic method to perform surface segmentation by combining not only LIDAR data but also images. A region-based method is proposed to generate a set of planar patches by grouping LIDAR points. The grouping criteria are based on both the coordinates of the points and the corresponding intensity values computed from the images. This method has been applied to urban data and the segmentation results are compared with the reference data acquired by manual segmentation. 76% of the test area is correctly segmented. Under-segmentation is rarely founded but over-segmentation still exists. If the over-segmentation is mitigated by merging adjacent patches with similar properties as a post-process, the proposed segmentation method can be effectively utilized for a reliable intermediate process toward automatic extraction of 3D model of the real world.

Optimization of Tri-enzyme Extraction Procedures for the Microbiological Assay of Folate in Red Kidney Bean and Roasted Peanut Using Response Surface Methodology

  • Choi, Young-Min;Eitenmiller, Ronald R.;Kim, Seon-Hee;Lee, Jun-Soo
    • Food Science and Biotechnology
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    • v.18 no.1
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    • pp.31-35
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    • 2009
  • Total folate content was determined by microbiological assay using Lactobacillus casei spp. rhamnosis (ATCC 7469) with a 96-well microplate technique. Using roasted peanut and red kidney beans as representative legume samples, response surface methodology (RSM) was supplied to optimize the trienzyme procedures for the determination of folate in legumes. After response surface regression (RSREG), the second-order polynomial equation was fitted to the experimental data. Ridge analysis showed that the optimal digestion times were <2 hr for $Pronase^{(R)}$ and $\alpha$-amylase, and <5 hr for conjugase to obtain maximal folate values for legume samples. This study confirms that established digestion times for cereal products (AOAC Method 2004.05) of 3 for protease and 2 hr for $\alpha$-amylase are applicable to legumes. Conjugase treatment can be reduced to 5 from 16 hr and the conjugase level to 5 from 20 mg per sample, providing significant cost saving.

Numerical Study of Polarization-Dependent Emission Properties of Localized-Surface-Plasmon-Coupled Light Emitting Diodes with Ag/SiO2 Na

  • Moon, Seul-Ki;Yang, Jin-Kyu
    • Journal of the Optical Society of Korea
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    • v.18 no.5
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    • pp.582-588
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    • 2014
  • We study polarization-dependent spontaneous emission (SE) rate and light extraction efficiency (LEE) in localized-surface-plasmon (LSP)-coupled light emitting diodes (LEDs). The closely packed seven $Ag/SiO_2$ core-shell (CS) nanoparticles (NPs) lie on top of the GaN surface for LSP coupling with a radiated dipole. According to the dipole direction, both the SE rate and the LEE are significantly modified by the LSP effect at the $Ag/SiO_2$ CS NPs when the size of Ag, the thickness of $SiO_2$, and the position of the dipole source are varied. The enhancement of the SE rate is related to an induced dipole effect at the Ag, and the high LEE is caused by light scattering with an LSP mode at $Ag/SiO_2$ CS NPs. We suggest the optimum position of the quantum well (QW) in blue InGaN/GaN LEDs with $Ag/SiO_2$ CS NPs for practical application.

Cytotoxic Effect of Isolated Protein-bound Polysaccharides from Hypsizigus marmoreus Extracts by Response Surface Methodology (반응표면분석에 의한 해송이버섯(Hypsizigus marmoreus) 추출물 중 단백다당체의 암세포 성장억제효과)

  • Jung, Eun-Bong;Jo, Jin-Ho;Cho, Seung-Mock
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.12
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    • pp.1647-1653
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    • 2008
  • This study used response surface methodology (RSM) in an effort to optimize the water extraction conditions of Hypsizigus marmoreus in order to increase cytotoxicity activity of the extract. A central composite design was applied to investigate the effects of independent variables, which included the extraction temperature ($X_1$), extraction time ($X_2$), the ratio of solvent to sample ($X_3$) on dependent variables of the extracts, including extraction yield ($Y_1$) and protein content ($Y_2$). The estimated optimal conditions were as follows: $51.3^{\circ}C$ extraction temperature, 8.2 hrs extraction time, and 46.7 mL/g of solvent per sample. The extract (CE) was extracted at optimal condition and crude polysaccharides (CPS) were obtained from CE by ethanol precipitation, dialysis, and freeze drying. Neutral (NPS) and acidic (APS) fraction of polysaccharides were seperated from CPS by ion chromatography. The growth inhibitory effects of the APS (0.5 mg/mL) on AGS human cancer cells were 73.97%. CPS showed the highest growth inhibitory effects on HepG2 human cancer cell at 0.5 mg/mL. However all fraction polysaccharides from Hypsizigus marmoreus showed lower than 20% growth inhibition on SW480 human cancer cell.

Optimization of microwave-assisted extraction process of Hordeum vulgare L. by response surface methodology (반응표면분석법을 이용한 새싹보리 마이크로웨이브 추출공정의 최적화)

  • Lee, Jae-Jun;Park, Dae-Hee;Lee, Won-Young
    • Food Science and Preservation
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    • v.24 no.7
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    • pp.949-956
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    • 2017
  • This study attempted to find optimum extract range of active ingredient for barley sprouts (Hordeum vulgare L.). Extracts from Hordeum vulgare L. were made by microwave extraction method and total polyphenol content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity (DPPH) were measured with extract of Hordeum vulgare L.. Response surface methodology (RSM) was applied to a extraction process, and central composite design (CCD) was also used for this process to examine the optimum condition. Independent variables ($X_n$) are concentration of ethanol ($X_1$: 0, 25, 50, 75, 100%), microwave power ($X_2$: 60, 120, 180, 240, 300 W), extraction time ($X_3$: 4, 8, 12, 16, 20 min). Dependent variables ($Y_n$) are TPC ($Y_1$), TFC ($Y_2$), DPPH radical scavenging ($Y_3$). It is formed by sixteen conditions to extract. The $R^2$ value of dependent variables is ranged from 0.90 to 0.97 (p<0.05). Experiments values within the optimal range (40% of ethanol concentration, 120 W of microwave power, 18 min of extraction time) were 3.74 mg GAE/g (TPC), 3.00 mg RE/g (TFC), 35.43% (DPPH), respectively. Under the optimized conditions, predicted value showed no significant difference comparing with the experimental values.

Establishment of Extraction Conditions for the Optimization of the Black Garlic Antioxidant Activity Using the Response Surface Methodology (반응표면분석을 이용한 흑마늘의 항산화 활성 최적화를 위한 추출조건 확립)

  • Kang, Jae-Ran;Lee, Soo-Jung;Kwon, Hyo-Jin;Kwon, Min-Hye;Sung, Nak-Ju
    • Food Science and Preservation
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    • v.19 no.4
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    • pp.577-585
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    • 2012
  • This study was conducted to establish the extraction conditions for the optimization of the biological activities of black garlic using the response surface methodology (RSM). The extraction conditions were based on the central composite design, with 15 kinds of variations in the extraction temperature (50-$90^{\circ}C$ ), extraction time (3-15 hrs), and ethanol concentration (0-100%). The total phenol, flavonoids, thiosulfinate contents, and anti-oxidant activity of black garlic extract were significantly higher at the J condition ($90^{\circ}C$ for 9 hrs with a 50% ethanol concentration). In this condition, the biological activities such as DPPH radical scavenging (66.10%), ABTS radical scavenging activity (75.02%), and reducing power by of FRAP (375.4 ${\mu}M/mL$) were excellent. Overall, the extraction conditions for the optimized biological activities of black garlic via RSM were expected to be at $89.68^{\circ}C$ for 9.79 hrs with a 55.72% ethanol concentration. The actual values were 96.4-114.8% of the predicted values.

Regional Linear Warping for Image Stitching with Dominant Edge Extraction

  • Yoo, Jisung;Hwang, Sung Soo;Kim, Seong Dae;Ki, Myung Seok;Cha, Jihun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.10
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    • pp.2464-2478
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    • 2013
  • Image stitching techniques produce an image with a wide field-of-view by aligning multiple images with a narrow field-of-view. While conventional algorithms successfully stitch images with a small parallax, structure misalignment may occur when input images contain a large parallax. This paper presents an image stitching algorithm that aligns images with a large parallax by regional linear warping. To this end, input images are first approximated as multiple planar surfaces, and different linear warping is applied to each planar surface. For approximating input images as multiple planar surfaces, the concept of dominant edges is introduced. Dominant edges are defined as conspicuous edges of lines in input images, and extracted dominant edges identify the boundaries of each planar surface. Dominant edge extraction is conducted by detecting distinct changes of local characteristics around strong edge pixels. Experimental results show that the proposed algorithm successfully stitches images with a large parallax without structure misalignment.

Concentration and Geochemical Phases of Heavy Metals in Marine Sediments in the Vicinity of the Coal-fired Power Plant of Korea (석탄화력발전소 주변해역 퇴적물 내의 중금속원소의 함량과 지화학적 존재형태)

  • Lee, Doo-Ho;Jeong, Yeon-Tae
    • Journal of Environmental Impact Assessment
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    • v.9 no.4
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    • pp.301-314
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    • 2000
  • Marine surface sediments in the vicinity of Samcheonpo coal-fired power plant were analyzed by a total analysis($HF+HNO_3+HClO_4$) and sequential extraction procedure for heavy metals in order to investigate the total concentrations and geochemical phases of heavy metals. The result showed that the concentrations of Cr, Cu, Fe and Zn were within ranges typical for coastal areas, which reflected the mineralogical composition of the sediments in the studied area. However, the distributions of Cd, Co, Mn, Ni and Pb were rather different from the former, indicating that these heavy metals had a different origin, or that they were affected by a different geochemical mechanism. Chemical partitioning of heavy metals using sequential extraction procedure revealed that Cu, Fe, Pb, Zn were significantly bound to the residual phases of the sediments, whereas carbonate phases contained considerable amounts of Mn. The significant association of Pb with the exchangeable fraction also indicated that Pb was more mobile and bioavailable than Cu, Fe, Mn, Zn.

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Characterization of a Blend-Biosurfactant of Glycolipid and Lipopeptide Produced by Bacillus subtilis TU2 Isolated from Underground Oil-Extraction Wastewater

  • Cheng, Fangyu;Tang, Cheng;Yang, Huan;Yu, Huimin;Chen, Yu;Shen, Zhongyao
    • Journal of Microbiology and Biotechnology
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    • v.23 no.3
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    • pp.390-396
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    • 2013
  • Biosurfactants have versatile properties and potential industrial applications. A new producer, B. subtilis TU2, was isolated from the underground oil-extraction wastewater of Shengli Oilfield, China. Preliminary flask culture showed that the titer of biosurfactant obtained from the broth of TU2 was ~1.5 g/l at 48 h (718 mg/l after purification), with a reduced surface tension of 32.5 mN/m. The critical micelle concentration was measured as 50 mg/l and the surface tension maintained stability in solution with 50 g/l NaCl and 16 g/l $CaCl_2$ after 5 days of incubation at $70^{\circ}C$. FT-IR spectra exhibited the structure information of both glycolipid and lipopeptide. MALDI-TOF-MS analyses confirmed that the biosurfactant produced by B. subtilis TU2 was a blend of glycolipid and lipopeptide, including rhamnolipid, surfactin, and fengycin. The blended biosurfactant showed 86% of oil-washing efficiency and fine emulsification activity on crude oil, suggesting its potential application in enhanced oil recovery.