• Title/Summary/Keyword: spectral study

Search Result 2,805, Processing Time 0.026 seconds

Evaluation of Autonomic Function in Patients with Hyperhidrosis by Power Spectral Analysis of Heart Rate Variability (심박변이도(Heart Rate Variability) 측정을 통한 다한증(多汗症)환자의 자율신경계(自律神經系)기능 평가)

  • Lee, Kun-Young;Lee, Hyung-Koo;Jung, Sung-Ki;Jung, Hee-Jae
    • The Journal of Internal Korean Medicine
    • /
    • v.29 no.1
    • /
    • pp.1-11
    • /
    • 2008
  • Objectives : Essential hyperhidrosis is a socially and occupationally disabling disorder. There are many suggestions that hyperhidrosis is associated with the autonomic nervous system. This study was designed to investigate the autonomic nerve system the patients with hyperhidrosis. Methods : 348 palmar and plantar hyperhidrosis patients and 20 systemic hyperhidrosis patients in the ambulatory care were investigated. All patients were inspected at the first medical examination, using the PSA of HRV. HRV was measured for 5 minutes after 5 minutes' bed rest. We checked the frequency domain analysis of HRV (i.e. TP, VLF, LF, HF and LF/HF) which were transformed into natural logarithm of patients against the standard measures of the HRV components. Then, we compared the means of patients with means and highest values of in the normal range of Koreans 1) between the patients with palmar and plantar hyperhidrosis and the healthy controls and 2) between the patients with the systemic hyperhidrosis and healthy controls, by the frequency domain analysis of heart rate variability (HRV), respectively. We then compared the results between 1) and 2). Results : The values of natural logarithmic measures of LF/HF ratio in the patients with palmar and plantar hyperhidrosis we examined were significantly higher than the values of healthy controls, but those in the patients with systemic hyperhidrosis were not higher. Conclusion : This study suggests that the autonomic nervous function did not simply increase but that the balance between sympathetic and parasympathetic nervous function did matter in patients with palmar and plantar hyperhidrosis. This balance included that the sympathetic nervous function aggravated comparatively with parasympathetic nervous function. On the other hand, we couldn't find any significance of the patients with the systemic hyperhidrosis as for the autonomic nervous function.

  • PDF

Exploring Optimal Threshold of RGB Pixel Values to Extract Road Features from Google Earth (Google Earth에서 도로 추출을 위한 RGB 화소값 최적구간 추적)

  • Park, Jae-Young;Um, Jung-Sup
    • Journal of Korea Spatial Information System Society
    • /
    • v.12 no.1
    • /
    • pp.66-75
    • /
    • 2010
  • The authors argues that the current road updating system based on traditional aerial photograph or multi-spectral satellite image appears to be non-user friendly due to lack of the frequent cartographic representation for the new construction sites. Google Earth are currently being emerged as one of important places to extract road features since the RGB satellite image with high multi-temporal resolution can be accessed freely over large areas. This paper is primarily intended to evaluate optimal threshold of RGB pixel values to extract road features from Google Earth. An empirical study for five experimental sites was conducted to confirm how a RGB picture provided Google Earth can be used to extact the road feature. The results indicate that optimal threshold of RGB pixel values to extract road features was identified as 126, 125, 127 for manual operation which corresponds to 25%, 30%, 19%. Also, it was found that display scale difference of Google Earth was not very influential in tracking required RGB pixel value. As a result the 61cm resolution of Quickbird RGB data has shown the potential to realistically identified the major type of road feature by large scale spatial precision while the typical algorithm revealed successfully the area-wide optimal threshold of RGB pixel for road appeared in the study area.

Study on Growth and Opto-Electrical Characterization of $CdS_{1-x}Se_{x}$ Thin Film using Chemical Bath Deposition Method (CBD 방법에 의한 $CdS_{1-x}Se_{x}$ 박막의 열처리에 따른 광전기적 특성)

  • Hong, K.J.;Choi, S.P.;Lee, S.Y.;You, S.H.;Shin, Y.J.;Lee, K.K.;Suh, S.S.;Kim, H.S.;Yun, E.H.;Kim, S.U.;Shin, Y.J.;Jeong, T.S.;Shin, H.K.;KIm, T.S.;Moon, J.D.;Jeon, S.L.
    • Journal of Sensor Science and Technology
    • /
    • v.4 no.1
    • /
    • pp.51-63
    • /
    • 1995
  • Polycrystalline $CdS_{1-x}Se_{x}$ thin films were grown on ceramic substrate using a chemical bath deposition method. They were annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometer in order to study $CdS_{1-x}Se_{x}$ polycrystal structure using extrapolation method of X-ray diffraction patterns for the CdS, CdSe samples annealed in $N_{2}$ gas at $550^{\circ}C$ it was found hexagonal structure which had the lattice constant $a_{0}=4.1364{\AA}$, $c_{0}=6.7129{\AA}$ in CdS and $a_{0}=4.3021{\AA}$, $c_{0}=7.0142{\AA}$ in CdSe, respectively. Hall effect on these samples was measured by Van der Pauw method and then studied on carrier density and mobility depending on temperature. We measured also spectral response, sensitivity(${\gamma}$), maximum allowable power dissipation and response time on these samples.

  • PDF

Isolation and Purification of Berberine in Cortex Phellodendri by Centrifugal Partition Chromatography (Centrifugal Partition Chromatography에 의한 황백으로부터 Berberine의 분리 및 정제)

  • Kim, Jung-Bae;Bang, Byung-Ho
    • The Korean Journal of Food And Nutrition
    • /
    • v.27 no.3
    • /
    • pp.532-537
    • /
    • 2014
  • Cortex Phellodendri (CP) is derived from the dried bark of Phellodendron amurense. It has been widely used as a drug in traditional Korea medicine for treating diarrhea, jaundice, swelling pains in the knees and feet, urinary tract infections, and infections of the body surface. Many analytical methods have been used to study oriental herbal medicines, such as thin-layer chromatography, column liquid chromatography, and high performance liquid chromatography (HPLC). In this study, preparative centrifugal partition chromatography (CPC) was successfully carried out in order to separate pure compounds from a CP methanol extract. The optimum two-phase CPC solvent system was composed of n-butanol: acetic acid: water (4:1:5 v/v/v). The flow rate of the mobile phase was 3 mL/min in ascending mode with rotation at 1,000 rpm. The CPC-separated fraction and purification procedures were carried out by preparatory HPLC. The $^1H$ NMR spectrum revealed that the resonances at ${\delta}$ 4.10 and 4.20 ppm corresponded to three protons ($-OCH_3$), whereas those at ${\delta}$ 6.10 ppm corresponded to two protons ($-OCH_2O-$). Further, two aromatic protons (H-11 and H-12) conveys a doublet-doublet pattern. The H-11 doublet and H-12 doublet appear at ${\delta}$ 7.98 and 8.11, respectively. The $^{13}C$ NMR. spectrum showed a tetrasubstituted with a methylenedioxy group at C2 and C3, and two methoxy groups at C9 and C10. The chemical structure of the berberine was identified by $^1H$, $^{13}C$-nuclear magnetic resonance and electrospray ionization-mass spectroscopy spectral data analysis.

A Study on Morphology and Mechanical Properties of Biodegradable Polymer Nanocomposites (생분해성 고분자 나노복합체의 형태학 및 기계적 특성 연구)

  • Jang, Sang Hee
    • Clean Technology
    • /
    • v.19 no.4
    • /
    • pp.401-409
    • /
    • 2013
  • BBiodegradable polymers have attracted great attention because of the increased environmental pollution by waste plastics. In this study, PLA (polylactic acid)/Clay-20 (Cloisite 20) and PLA (polylactic acid)/PBS (poly(butylene succinate)/Clay-20 (Cloisite 20) nanocomposites were manufactured in a twin-screw extruder. Specimens for mechanical properties of PLA/Clay-20 and PLA/PBS (90/10)/Clay-20 nanocomposites were prepared by injection molding. Thermal, mechanical, morphological and raman spectral properties of two nanocomposites were investigated by differential scanning calorimetry (DSC), tensile tester, scanning electron microscopy (SEM) and raman-microscope spectrophotometer, respectively. In addition, hydrolytic degradation properties of two nanocomposites were investigated by hydrolytic degradation test. It was confirmed that the crystallinity of PLA/Clay-20 and PLA/PBS/Clay-20 nanocomposite was increased with increasing Clay-20 content and the Clay-20 is miscible with PLA and PLA/PBS resin from DSC and SEM results. Tensile strength of two nanocomposites was decreased, but thier elongation, impact strength, tensile modulus and flexural modulus were increased with an increase of Clay-20 content. The impact strength of PLA/Clay-20 and PLA/PBS/Clay-20 nanocomposites with 5 wt% of Clay-20 content was increased above twice than that of pure PLA and PLA/PBS (90/10). The hydrolytic degradation rate of PLA/Clay-20 nanocomposite with 3 wt% of Clay-20 content was accelerated about twice than that of pure PLA. The reason is that degradation may occur in the PLA and Clay-20 interface easily because of hydrophilic property of organic Clay-20. It was confirmed that a proper amount of Clay-20 can improve the mechanical properties of PLA and can control biodegradable property of PLA.

Generation of the Ortho-Rectified Photo Map and Analysis of the Three-Dimensional Image Using the PKNU 2 Imagery (PKNU2호 영상을 이용한 정사영상 지도 제작 및 3차원 입체 분석)

  • Lee, Chang Hun;Choi, Chul Uong
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.7 no.4
    • /
    • pp.77-87
    • /
    • 2004
  • It is important for hydrographers to extract the accurate cross section of a river for the hydrographical analysis of the topography. Aerial photographs were used to extract the cross section of a river for the advantages of the accuracy and economical efficiency in this study, while the direct measurement has been used in existing studies. An ortho-rectified photo map using imageries taken by the PKNU 2 (High-resolution, multi-spectral, aerial photographic system developed by our laboratory) was generated using the surveyed data and a digital map. The cross section of a river that was obtained from the ortho-rectified by the surveyed Kinematic data of GPS was compared with the result using ImageStation stereo-plotter of corp. Z/I Imaging. As a result of this study, the RMSE in the ortho-rect process using the surveyed GPS data was lowered as from 5.5788 pixels (about 2m) to 2.84 (about 1m) in comparison with it in the process using a digital map. The surveyed kinematic GPS in extraction of the cross section of a river was excellent as 6.6cm of the planimetric and precision in the confidence level of 95%. The correlation coefficient between the result from the using stereo-plotter and the extraction of cross section of a river using aerial photos was 0.8 hydrographical acquisition of it using PKNU 2 imagery will be possible.

  • PDF

Classification of Crop Cultivation Areas Using Active Learning and Temporal Contextual Information (능동 학습과 시간 문맥 정보를 이용한 작물 재배지역 분류)

  • KIM, Ye-Seul;YOO, Hee-Young;PARK, No-Wook;LEE, Kyung-Do
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.18 no.3
    • /
    • pp.76-88
    • /
    • 2015
  • This paper presents a classification method based on the combination of active learning with temporal contextual information extracted from past land-cover maps for the classification of crop cultivation areas. Iterative classification based on active learning is designed to extract reliable training data and cultivation rules from past land-cover maps are quantified as temporal contextual information to be used for not only assignment of training data but also relaxation of spectral ambiguity. To evaluate the applicability of the classification method proposed in this paper, a case study with MODIS time-series vegetation index data sets and past cropland data layers(CDLs) is carried out for the classification of corn and soybean in Illinois state, USA. Iterative classification based on active learning could reduce misclassification both between corn and soybean and between other crops and non crops. The combination of temporal contextual information also reduced the over-estimation results in major crops and led to the best classification accuracy. Thus, these case study results confirm that the proposed classification method can be effectively applied for crop cultivation areas where it is not easy to collect the sufficient number of reliable training data.

Estimation of Subsurface Structure and Ground Response by Microtremor (상시미동에 의한 지하구조와 지반응답의 추정)

  • Hwang, Min-Woo;Kim, Sung-Kyun
    • Journal of the Korean earth science society
    • /
    • v.23 no.4
    • /
    • pp.380-392
    • /
    • 2002
  • The purpose of the present study is to evaluate the usage of microtremor in estimation of subsurface structure and ground response to strong ground motion. To accomplish the purpose, the current status of microtremor study are reviewed and microtremors recorded at several stations are analysed. First of all, the stability of microtremor is examined through the analysis of microtremors recorded for 80 seconds per hour during the time from 10 p.m. to 6 a.m. for eight hours at night time. It is found that the shape of microtremor spectra of low frequency below 10Hz is approximately invariable with time and the spectra contain informations about subsurface structure. The subsurface structures estimated from the predominant frequency determined from the recorded microtremors are compared with the known ones from geophysical surveys at several stations in Kyungju. The comparison of structures shows rough agreements at most stations. Horizontal to vertical spectral ratio(HVSR) technique for microtremor has been proposed as an indirect method to determine ground response to strong ground motion. The HVSR for microtremors recorded in Kyungju is calculated and compared with theoretical transfer function calculated from the known structures. The comparison shows rough coincidence of the peak frequency of spectra between them.

Comparing Quantitative EEG and Low Resolution Electromagnetic Tomography Imaging between Deficit Syndrome and Non-Deficit Syndrome of Schizophrenia (정신분열병의 결핍증후군과 비결핍증후군에서 QEEG와 sLORETA를 이용한 비교연구)

  • Lee, Sang-Eun;Yim, Seon-Jin;Lee, Mi-Gyung;Lee, Jae-Won;Han, Kyu-Hee;Lee, Jong-Il;Sim, Min-Young;Yoon, Hai-Joo;Shin, Byoung-Hak
    • Sleep Medicine and Psychophysiology
    • /
    • v.17 no.2
    • /
    • pp.91-99
    • /
    • 2010
  • Objectives: Deficit schizophrenia (DS) constitutes a disease separate from non-deficit schizophrenia (NDS). The aim of the current study was to compare the quantitative EEG and low resolution electromagnetic tomography (LORETA) imaging between DS and NDS. Methods: This study was performed by 32 channels EEG for 42 schizophrenia patients who we categorized into DS and NDS using proxy instrument deficit syndrome (PDS). We performed the absolute power spectral analyses for delta, theta, alpha, low beta and high beta activities. We compared power spectrum between two groups using Independent t-test. Partial correlation test was performed with clinical parameters. Standardized LORETA (sLORETA) was used for comparison of cortical activity, and statistical nonparametric mapping (SnPM) was applied for the statistical analysis. Results: DS showed significantly increased delta and theta absolute power in fontal and parietal region compared with NDS (p<0.05). Power spectrum showed significant correlation with 'anergia' and 'hostility/suspiciousness' subscale of brief psychiatric rating scale (BPRS)(p<0.05). sLORETA found out the source region (anterior cingulate cortex/limbic part) that delta activity was significantly increased in DS (p=0.042). Conclusions: DS showed different cortical activity compared with NDS. Our results may suggest QEEG and LORETA could be the marker in differentiating between DS and NDS.

  • PDF

Development of Automatic Sorting System for Black Plastics Using Laser Induced Breakdown Spectroscopy (LIBS) (LIBS를 이용한 흑색 플라스틱의 자동선별 시스템 개발)

  • Park, Eun Kyu;Jung, Bam Bit;Choi, Woo Zin;Oh, Sung Kwun
    • Resources Recycling
    • /
    • v.26 no.6
    • /
    • pp.73-83
    • /
    • 2017
  • Used small household appliances have a wide variety of product types and component materials, and contain high percentage of black plastics. However, they are not being recycled efficiently as conventional sensors such as near-infrared ray (NIR), etc. are not able to detect black plastic by types. In the present study, an automatic sorting system was developed based on laser-induced breakdown spectroscopy (LIBS) to promote the recycling of waste plastics. The system we developed mainly consists of sample feeder, automatic position recognition system, LIBS device, separator and control unit. By applying laser pulse on the target sample, characteristic spectral data can be obtained and analyzed by using CCD detectors. The obtained data was then treated by using a classifier, which was developed based on artificial intelligent algorithm. The separation tests on waste plastics also were carried out by using a lab-scale automatic sorting system and the test results will be discussed. The classification rate of the radial basis neural network (RBFNNs) classifier developed in this study was about > 97%. The recognition rate of the black plastic by types with the automatic sorting system was more than 94.0% and the sorting efficiency was more than 80.0%. Automatic sorting system based on LIBS technology is in its infant stage and it has a high potential for utilization in and outside Korea due to its excellent economic efficiency.