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Study on the Effect of Acupuncture at Jeonjung($CV_{17}$) on the Heart Rate Variability in Healthy Adults (단중혈(膻中穴) 침자극이 정상 성인의 심박변이도에 미치는 영향)

  • Park, Jin-Soo;Ahn, Min-Seob;Lee, Jeong-Ju;Choi, Byoung-Sun;Park, Min-Cheol;Yang, Hyun-Ju;Park, Ga-Young;Kim, Min-Chul;Jo, Eun-Heui
    • Journal of Acupuncture Research
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    • v.28 no.2
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    • pp.13-25
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    • 2011
  • Objectives : This study was accomplished to investigate the effects of acupuncture at Jeonjung($CV_{17}$) on the heart rate variability(HRV) in healthy adults. And based on that, we tried to find out how acupuncture at Jeonjung($CV_{17}$) effects on the activity and balance of the autonomic nervous system. Methods : We investigated on 74 healthy volunteers consisted of 24 subjects in acupuncture group, 24 subjects in sham acupuncture group and 24 subjects in control group. On the other hand, two volunteers were ruled out by standard of elimination. The study was established by randomized trial. Acupuncture was applied at Jeonjung($CV_{17}$) during 10 minutes in acupuncture group and minimal acupuncture was applied at the same area in sham acupuncture group. No treatment was executed in control group. We measured HRV 3 times : baseline measurement and after treatment in acupuncture group and sham acupuncture group (after rest in control group) twise. The SPSS 15.0 for Windows was used to analyze the data by paired t-test, Wilcoxon signed ranks test (in group) and One-Way ANOVA, Kruskal-Wallis test (between the groups). Results: 1. In acupuncture group, Mean HRT, PSI, Normalized HF decreased significantly. SDNN, Ln (TP), Ln (LF), Ln (VLF), Normalized LF and LF/HF ratio increased significantly. RMSSD, Ln(HF) were not affected. 2. In sham acupuncture group, all indicators were not affected. 3. In control group, mean HRT, Ln(TP) decreased significantly. SDNN, RMSSD, PSI, Ln(LF), Ln(HF), Ln(VLF), normalized LF, normalized HF and LF/HF ratio were not affected. Conclusions : We suggest that acupuncture at Jeonjung($CV_{17}$) increases the activity of autonomic nervous system and makes effects on the balance of the autonomic nervous system.

Analysis of the Relationship between Landform and Forest Fire Severity (지형과 산불피해도와의 관계 분석)

  • Lee, Byung-Doo;Won, Myoung-Soo;Jang, Kwang-Min;Lee, Myung-Bo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.1
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    • pp.58-67
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    • 2008
  • Topography factors, as homeostasis variables at forest fire, affect the formation of fuel load patterns, atmospheric phenomena and forest fire behavior. Examination of the correlation between landforms and fire severity is important to decision making for fire hazard analysis and fighting strategies. In this study, fire severity was analyzed using Normalized Burn Ratio(NBR) derived from pre- and post-fire Landsat TM/+ETM images and landform were classified based on Topographic Position Index(TPI) in Samcheok(2000), Cheongyang(2002), and Yangyang(2005) forest fire regions. F-tests and Duncan's multi-range test between landform and fire severity showed that fire severities of headwater, high ridges, and upper slopes is higher than ones of local ridges, midslope ridges, and plains. Fire severity were more sensitive in coniferous forest than broadleaf forests.

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Comparison of SGM Cost for DSM Generation Using Satellite Images (위성영상으로 DSM을 생성하기 위한 SGM Cost의 비교)

  • Lee, Hyoseong;Park, Soonyoung;Kwon, Wonsuk;Han, Dongyeob
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.6
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    • pp.473-479
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    • 2019
  • This study applied SGM (Semi Global Matching) to generate DSM (Digital Surface Model) using WorldView-1 high-resolution satellite stereo pair in Terrassa, Spain provided by ISPRS (International Society for Photogrammetry and Remote Sensing). The SGM is an image matching algorithm that performs the computation of the matching cost for the stereo pair in multi-paths and aggregates the computed costs sequentially. This method finally calculates the disparity corresponding to the minimum (or maximum) value of the aggregation cost. The cost was applied to MI (Mutual Information), NCC (Normalized Cross-Correlation), and CT (Census Transform) in order to the SGM. The accuracy and performance of the outline representation result in DSM by each cost are presented. Based on the images used and the subject area, the accuracy of the CT cost results was the highest, and the outline representation was also most clearly depicted. In addition, while the SGM method represented more detailed outlines than the existing software, many errors occurred in the water area.

Terrace Fields Classification in North Korea Using MODIS Multi-temporal Image Data (MODIS 다중시기 영상을 이용한 북한 다락밭 분류)

  • Jeong, Seung Gyu;Park, Jonghoon;Park, Chong Hwa;Lee, Dong Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.1
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    • pp.73-83
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    • 2016
  • Forest degradation reduces ecosystem services provided by forest and could lead to change in composition of species. In North Korea, there has been significant forest degradation due to conversion of forest into terrace fields for food production and cut-down of forest for fuel woods. This study analyzed the phenological changes in North Korea, in terms of vegetation and moisture in soil and vegetation, from March to Octorber 2013, using MODIS (MODerate resolution Imaging Spectroradiometer) images and indexes including NDVI (Normalized Difference Vegetation Index), NDSI (Normalized Difference Soil Index), and NDWI (Normalized Difference Water Index). In addition, marginal farmland was derived using elevation data. Lastly, degraded terrace fields of 16 degree was analyzed using NDVI, NDSI, and NDWI indexes, and marginal farmland characteristics with slope variable. The accuracy value of land cover classification, which shows the difference between the observation and analyzed value, was 84.9% and Kappa value was 0.82. The highest accuracy value was from agricultural (paddy, field) and forest area. Terrace fields were easily identified using slope data form agricultural field. Use of NDVI, NDSI, and NDWI is more effective in distinguishing deforested terrace field from agricultural area. NDVI only shows vegetation difference whereas NDSI classifies soil moisture values and NDWI classifies abandoned agricultural fields based on moisture values. The method used in this study allowed more effective identification of deforested terrace fields, which visually illustrates forest degradation problem in North Korea.

Application of Normalized Vegetation Index for Estimating Hydrological Factors in the Korea Peninsula from COMS (한반도 지역에서의 수문인자산정을 위한 식생 정보 분석 및 활용 ; 천리안 위성을 이용하여)

  • Park, Jongmin;Baik, Jongjin;Kim, Seong-Joon;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.47 no.10
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    • pp.935-943
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    • 2014
  • Normalized Difference Vegetation Index (NDVI) used as input data for various hydrologic models plays a key role in understanding the variation of Hydrometeological parameters and Interaction between surface and atmosphere. Many studies have been conducted to estimate accurate remotely-sensed NDVI using spectral characteristics of vegetation. In this study, we conducted comparative analysis between Communication, Ocean and Meteorological Satellite and MOderate-Resolution Imaging Spectroradiometer (MODIS) NDVI. For comparison, Maximum Value Composite (MVC) was used to estimate 8-day and 16-day composite COMS NDVI. Both 8-day and 16-day COMS NDVI showed high statistical results compared with MODIS NDVI. Based on the results in this study, it can be concluded that COMS can be widely applicable for further ecological and hydrological studies.

Image Stitching Using Normalized Cross-Correlation and the Thresholding Method in a Fluorescence Microscopy Image of Brain Tumor Cells (정규 상호상관도 및 이진화 기법을 이용한 뇌종양 세포의 형광 현미경 영상 스티칭)

  • Seo, Ji Hyun;Kang, Mi-Sun;Kim, Hyun-jung;Kim, Myoung-Hee
    • Journal of Korea Multimedia Society
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    • v.20 no.7
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    • pp.979-985
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    • 2017
  • This paper, which covers a fluorescence microscopy image of brain tumor cells, looks at drug reactions by treating different types and concentrations of drugs on a plate of $24{\times}16$ wells. Due to the limitation of the field of view, a well was taken into 9 field images, and each has an overlapping area with its neighboring fields. To analyze more precisely, image stitching is needed. The basic method is finding a similar area using normalized cross-correlation (NCC). The problem is that some overlapping areas may not have any duplicated cells that help to find the matching point. In addition, the cell objects have similar sizes and shapes, which makes distinguishing them difficult. To avoid calculating similarity between blank areas and roughly distinguishing different cells, thresholding is added. The thresholding method classifies background and cell objects based on fixed thresholds and finds the location of the first seen cell. After getting its location, NCC is used to find the best correlation point. The results are compared with a simple boundary stitched image. Our proposed method stitches images that are connected in a grid form without collision, selecting the best correlation point among areas that contain overlapping cells and ones without it.

Comparison of field- and satellite-based vegetation cover estimation methods

  • Ko, Dongwook W.;Kim, Dasom;Narantsetseg, Amartuvshin;Kang, Sinkyu
    • Journal of Ecology and Environment
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    • v.41 no.2
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    • pp.34-44
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    • 2017
  • Background: Monitoring terrestrial vegetation cover condition is important to evaluate its current condition and to identify potential vulnerabilities. Due to simplicity and low cost, point intercept method has been widely used in evaluating grassland surface and quantifying cover conditions. Field-based digital photography method is gaining popularity for the purpose of cover estimate, as it can reduce field time and enable additional analysis in the future. However, the caveats and uncertainty among field-based vegetation cover estimation methods is not well known, especially across a wide range of cover conditions. We compared cover estimates from point intercept and digital photography methods with varying sampling intensities (25, 49, and 100 points within an image), across 61 transects in typical steppe, forest steppe, and desert steppe in central Mongolia. We classified three photosynthetic groups of cover important to grassland ecosystem functioning: photosynthetic vegetation, non-photosynthetic vegetation, and bare soil. We also acquired normalized difference vegetation index from satellite image comparison with the field-based cover. Results: Photosynthetic vegetation estimates by point intercept method were correlated with normalized difference vegetation index, with improvement when non-photosynthetic vegetation was combined. For digital photography method, photosynthetic and non-photosynthetic vegetation estimates showed no correlation with normalized difference vegetation index, but combining of both showed moderate and significant correlation, which slightly increased with greater sampling intensity. Conclusions: Results imply that varying greenness is playing an important role in classification accuracy confusion. We suggest adopting measures to reduce observer bias and better distinguishing greenness levels in combination with multispectral indices to improve estimates on dry matter.

A Fast Fractal Image Compression Using The Normalized Variance (정규화된 분산을 이용한 프랙탈 압축방법)

  • Kim, Jong-Koo;Hamn, Do-Yong;Wee, Young-Cheul;Kimn, Ha-Jine
    • The KIPS Transactions:PartA
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    • v.8A no.4
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    • pp.499-502
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    • 2001
  • Fractal image coding suffers from the long search time of domain pool although it provides many properties including the high compression ratio. We find that the normalized variance of a block is independent of contrast, brightness. Using this observation, we introduce a self similar block searching method employing the d-dimensional nearest neighbor searching. This method takes Ο(log/N) time for searching the self similar domain blocks for each range block where N is the number of domain blocks. PSNR (Peak Signal Noise Ratio) of this method is similar to that of the full search method that requires Ο(N) time for each range block. Moreover, the image quality of this method is independent of the number of edges in the image.

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Comparative field tests on uplift behavior of straight-sided and belled shafts in loess under an arid environment

  • Qian, Zeng-zhen;Lu, Xian-long;Yang, Wen-zhi;Cui, Qiang
    • Geomechanics and Engineering
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    • v.11 no.1
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    • pp.141-160
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    • 2016
  • This study elucidates the uplift behaviors of the straight-sided and belled shafts. The field uplift load tests were carried out on 18 straight-sided and 15 belled shafts at the three collapsible loess sites under an arid environment on the Loess Plateau in Northwest China. Both the site conditions and the load tests were documented comprehensively. In general, the uplift load-displacement curves of the straight-sided and belled shafts approximately exhibited an initial linear, a curvilinear transition, and a final linear region, but did not provide a well defined peak or asymptotic value of the load, and therefore their uplift resistances should be interpreted from the load test results using an appropriate criterion. Nine representative uplift resistance interpretation criteria were used to define the "interpreted failure load" for each of the load tests, and all of these interpreted uplift resistances were normalized by the failure threshold, $T_{L2}$, obtained using the $L_1-L_2$ method. These load test data were compared statistically and graphically. For the straight-sided and belled shafts, the normalized uplift load-displacement curves were respectively established by the plots that related the mean interpreted uplift resistance ratio against the mean displacement at the corresponding interpreted criteria, and the comparisons of the normalized load-displacement curves were made. Specific recommendations for the designs of uplift belled and straight-sided shafts in the loess were given, in terms of both capacity and displacement.

The Effect of Moxibustion at Jeonjung($CV_{17}$) on the Heart Rate Variability in Healthy Adults (膻中穴($CV_{17}$) 간접구요법이 정상 성인의 심박변이도(HRV)에 미치는 영향)

  • Lee, Jeong-Ju;Kim, Seong-Joung;Park, Ok-Ju;Lee, Sang-Mi;Park, Min-Cheol;Jo, Eun-Heui
    • Journal of Acupuncture Research
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    • v.29 no.4
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    • pp.43-53
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    • 2012
  • Objectives : This study was accomplished to investigate the effects of moxibustion at Jeonjung($CV_{17}$) on the heart rate variability(HRV) in healthy adults. And based on that, we tried to find out how moxibustion at Jeonjung($CV_{17}$) effects on the activity and balance of the autonomic nervous system Methods : We investigated on 50 healthy volunteers consisted of 24 subjects in moxibustion group and 24 subjects in control group. On the other hand, two volunteers were ruled out by standard of elimination. The study was established by randomized trial. Moxibustion was applied at Jeonjung($CV_{17}$) and rested during 10 minutes in moxibustion group. No treatment was executed in control group. We measured HRV 3 times : baseline measurement and after treatment in moxibustion group(after rest in control group) twice. The SPSS 12.0 for windows was used to analyze the data by paired t-test, Wilcoxon signed ranks test(in group) and Independent t-test, Mann-Whitney U-test (between the groups). Results : 1. In moxibustion group, mean HRT decreased significantly. Ln(VLF) increased significantly. Ln(TP) decreased significantly at $2^{nd}$ time and increased significantly at $3^{rd}$ time. SDNN, RMSSD, PSI, Ln(LF), Ln(HF), Normalized LF, Normalized HF and LF/HF ratio were not affected. 2. In control group, PSI and normalized HF decreased significantly. SDNN, Ln(TP), Ln(VLF), normalized LF and LF/HF ratio increased significantly. Mean HRT, RMSSD, Ln(LF) and Ln(HF) were not affected. Conclusions : This study suggest that moxibustion at Jeonjung($CV_{17}$) makes no effects on the balance of the autonomic nervous system.