• 제목/요약/키워드: R-Peak

검색결과 1,514건 처리시간 0.028초

정밀주조용 쉘 몰드에 알루미노실리케이트계 졸의 응용에 관한 연구 ( I ) (A Study on the Application of Aluminosilicate Sols in Shell Mold for Investment Casting ( I ))

  • 김재원;김두현;서성문;조창용;최승주;김재철;박영규
    • 한국재료학회지
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    • 제9권12호
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    • pp.1188-1195
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    • 1999
  • 알루미노실리케이트 계 졸이 지르콘 쉘 몰드의 뮬라이트 층 생성에 미치는 영향을 고찰하였다. 알루미노실리케이트 졸은 콜로이달 실리카와 수용성 질산알루미늄을 혼합하여 제조하였으며 50$^{\circ}C$에서 48시간 조건에서 겔화 하였다. 이러한 겔은 깁사이트 및 알루미노실리케이트 복합 겔로 구성되어 있었으며, Si 이온과 결합하는 모든 Al 이온의 배위수가 4임을 확인하였다. 뮬라이트 상은 1300$^{\circ}C$ 이상에서 소결하였을 때 관찰되었으며 뮬라이트의 XRD 피크는 소결 온도와 질산알루미늄의 농도가 증가할수록 노실리케이트 졸 슬러리를 2차 층에 코팅하였다. 그 결과 1차 및 3차 층의 분리가 일어났으며, 이는 소결시 졸의 1차 및 3차 층으로 침윤 발생과 잔류 실리카와 뮬라이트 간의 열팽창계수 차이에 기인한 것으로 판단된다.

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만성 요통 환자의 골반지표와 발의 생체역학적 특징 연구 (Study on Pelvic Parameters and Biomechanical Characteristics of Foot in Patients with Chronic Low Back Pain)

  • 공재철;문수정;조동찬;고연석;송용선;이정한
    • 동의생리병리학회지
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    • 제26권1호
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    • pp.81-87
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    • 2012
  • The structural and biomechanical characteristics of pelvic and foot are important factors of back pain, but it is still complicated to clearly explain the relationship among them. The purpose of this study was to find out the characteristic of pelvic parameters and biomechanics of foot in patients with low back pain. Thirty-three female subjects with chronic low back pain were enrolled and ODI and VAS score were measured for back pain index. All subjects were taken the X-ray examination for major pelvic parameters and foot scan analysis for foot pressure, gait angle, fore-foot/rear-foot peak pressure ratio and asymmetric index. Statistical analysis were performed to examine the inter-relation between the measurement. As a result, it was shown the positive interrelation between back pain and F/R ratio, but others were not shown the relationship related to low back pain. And there were correlations between the lumbo-pelvic structure and biomechanics of foot in some aspects, but the causal relationship between them are still indefinable. In order to get more information about structures and biomechanics related to low back pain, subsequent researches are needed.

식품학적 가공에 의한 생약의 성분 및 활성 변화 III - Roasting 처리에 의한 천문동 중 HMF 함량변화 - (Changes in Chemical Composition and Biological Activities of Original Crude Drugs by Food Processing Techniques III - Changes of HMF Contents from Roasted Asparagi Tuber -)

  • 곽혜민;김자영;임정현;정신교;권순호;정현희;허종문;송경식
    • 생약학회지
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    • 제36권3호통권142호
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    • pp.235-239
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    • 2005
  • Changes in chemical composition of the ethanolic extract of roasted Asparagi Tuber were investigated by HPLC. One dramatically increased peak $(t_R\;14.85 min)$ was isolated by silica gel column chromatograph and identified as 5-hydroxymethyl furfural (HMF) by comparing its $1^H-NMR$ data with that of a commercial standard. HMF content reached its maximum level at $190^{\circ}C$ for 60 minutes. Under these conditions, HMF contents in the roasted Asparagi Tuber was increased about thirteen times (9.26mg/g) over the not-roasted control (0.71 mg/g). No significant differences were found in macrophage-activating, prolyl endopeptidase-inhibiting, antioxidative (DPPH), anti-coagulating (activated partial thromboplastin times), and ACE-inhibiting activities between roasted and not-roasted Asparagi Tuber.

전자현미경을 이용한 건물내 비고형 표면자재의 석면 오염 및 기중 석면농도 특성조사 (Characterization of Asbestos Content in Friable Sprayed-on Surface Material and Airborne Asbestos Concentrations in Buildings by TEM)

  • 유성환;김현욱
    • 한국산업보건학회지
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    • 제6권2호
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    • pp.165-175
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    • 1996
  • Fourteen(14) large commercial buildings located in Seoul with friable sprayed-on surface insulation material on ceiling were investigated for fiber types in bulk material and for airborne fiber concentrations in buildings by transmission electron microscopy (TEM) in order to compare the results with those by polarized light microscopy (PLM) and phase contrast microscopy (PCM). The results were as follows: 1. Chrysotile asbestos was found in one bulk sample out of total 14 bulk samples collected. Glass fiber and mineral wool were the two major constituents of the bulk samples. 2. The Na-Mg-Si-Ca-Fe-Al ratios of the EDX spectra which were normalized with the Si peak were 0-1.0-10-8.3-4.0-4.0 in mineral wool and 0-5-10-21-0-0 in chrysotile asbestos, respectively. 3. Airborne fiber concentrations were log-normalcy distributed and the geometric mean (geometric standard deviation) fiber concentrations by TEM in the underground parking lots and inside buildings were 0.0048 f/cc(1.93) and 0.0040 f/cc(2.27), respectively with no statistical difference. In the outdoor ambient air, statistically significantly lower concentration of 0.0018 f/cc(2.04) was measured. 4. The TEM/PCM ratios of airborne fiber concentrations ranged 0.5 - 2.0 for 80 % of airborne samples analyzed, end the regression equation between TEM and PCM was PCM=-0.2724+1.1355(TEM) with the coefficient of determination $R^2=0.52$. The results of this study confirmed that the sprayed-on surface insulation material found in some commercial buildings may possibly be contaminated with asbestos fiber. Since statistically significant relationship of fiber concentrations measured by PCM and TEM inside buildings and ambient air was found, previous results by PCM in ambient air could be used to estimate the ambient fiber concentrations in knowing the ratio of TEM/PCM.

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고아미 2호 쌀가루의 특성이 가래떡의 품질에 미치는 영향 (Effects Rice Powder Properties of 'Goami 2' on the Quality of Garaetteok)

  • 신동선;김성옥
    • 한국식품영양학회지
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    • 제30권4호
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    • pp.804-812
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    • 2017
  • This study investigated the effects of Goami 2 on the properties of Garaetteok. The moisture, crude protein, crude lipid and crude ash contents of the rice were 16.02, 5.40, 1.87 and 0.77%, respectively. The amylose contents (32.16%) and total dietary fiber contents (9.03%) were the highest in Goami 2. The water binding capacity of Goami 2 (167.84%) was higher than general rice flour. Using a rapid visco analyzer (RVA), the initial pasting temperature of Goami 2 was found to be the highest; also, the peak viscosities of Goami 2 were higher than general rice powder. To assess the effect of Goami 2 on the quality characteristics of Garaetteok, the rice-cake was made by adding various amounts of Goami 2 (0, 10, 20, 30, and 40% w/w) to rice. It was observed that higher the amount of added Goami 2, lower were the grades. In terms of the color values of Goami 2 addition, the L-values of Garaetteok were lower with increasing amount of Goami 2; addition of 40% Goami 2 had the lowest value. The textural properties (hardness) also showed that tteok containing the greater amounts of Goami 2 were considerably harder compared with the control. Sensory preference tests revealed that addition of less Goami 2 had the highest scores for appearance, color and overall acceptability, and the Goami 2 added was lower than control. Therefore, as compared to others cultivars, rice flour proved the most acceptable for the preparation of Garaetteok with cultivar rice.

Ga doped ZnO 박막의 질소분위기 열처리에 따른 특성 변화 (Effect of Annealing in Nitrogen Atmosphere on the Characteristics of Ga Doped ZnO Films)

  • 허성보;이영진;이학민;김선광;김유성;공영민;김대일
    • 열처리공학회지
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    • 제24권6호
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    • pp.338-342
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    • 2011
  • Ga doped ZnO (GZO) thin films were deposited with RF magnetron sputtering on glass substrate and then the effect of post deposition annealing at nitrogen atmosphere on the structural, optical and electrical properties of the films was investigated. The post deposition annealing process was conducted for 30 minutes at different temperature of 150, 300 and $450^{\circ}C$, respectively. As increase annealing temperature, GZO films show the increment of the prefer orientation of ZnO (002) diffraction peak in the XRD pattern and the optical transmittance in a visible wave region was also increased, while the electrical sheet resistance was decreased. The figure of merit obtained in this study means that GZO films which vacuum annealed at $450^{\circ}C$ have the highest optoelectrical performance in this study.

심장의 전기활동 측정이 가능한 체중계 설계에 관한 연구 (A Study on the Weighing scales Design for Electrical Activity Monitoring of the Heart)

  • 이강휘;강승진;김경남;민세동;최동학;이정환
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2015년도 추계학술발표대회
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    • pp.1822-1825
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    • 2015
  • 본 논문에서는 운동 전후 또는 심장 질환과 관련 있는 사용자가 체중을 측정하면서 동시에 심전도 신호를 측정하여 운동 부하에 따른 심장의 활동 상태를 모니터링 할 수 있는 장치를 고안하였다. 이를 위한 방법으로 체중계에 수정된 바이폴라 금속전극을 적용하여 표준사지 측정법을 이용하여 심장활동 신호를 측정할 수 있는 방법을 제안하였다. 체중계에서 심전도를 측정하기 위해 기존의 Ag-AgCl 전극이 아닌 금속 판 형태의 전극을 사용하였으며 이를 위해 입력 임피던스의 설계를 브릿지 형의 AC-Coupling 회로를 통해 높은 CMRR이 유지되도록 설계하였다. 또한 시시각각 변화하는 노이즈를 제거하기 위해 Savitzky-golay filter를 사용하였으며 이를 통해 Baseline wandering 이 제거된 최종 심장활동 신호를 획득하였다. R-peak 검출을 통해 기준신호와의 심박수 및 Sensitivity의 비교평가를 수행하여 이 장치의 성능을 평가한 결과 심박 검출률의 평균 Sensitivity가 97.1%로 나타났다. 동잡음 제거에 대한 알고리즘이 보다 최적화 되어 최종 출력 신호의 안정성이 향상 된다면 체중계를 통한 심박 검출의 가능성과 그 유효성이 충분할 것으로 사료된다.

동축형 스월-제트 분사기의 음향가진에 따른 동특성 (Dynamic Characteristics of Coaxial Swirl-jet Injector with Acoustic Excitation)

  • 배진현;김태성;정석규;정찬영;최정열;윤영빈
    • 한국추진공학회지
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    • 제22권4호
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    • pp.99-107
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    • 2018
  • 본 연구에서는 제트 유동 증가에 따라 스피커로 제트와 스월 유동에 각각 가진을 가하여 기체-기체 동축형 제트-스월 분사기의 분사기 전달함수(Injector Transfer Function, ITF)을 측정하였다. 공급시스템의 길이를 변화시켜 ITF를 측정한 결과 공급시스템의 공진주파수에서 피크가 발생하는 것을 확인할 수 있었다. 제트 유동에 가진을 줄 때, 제트 유동이 증가함에 따라 ITF의 크기는 감소하다가 다시 증가하는 것을 확인할 수 있었다. 즉, 두 유동의 속도차가 클수록 ITF의 크기가 증가하였다. 스월 가진 시 제트 유동이 증가함에 따라 ITF가 감소하는 것을 확인할 수 있었는데, 이는 후단에서 일정 유량 대비 가진 에너지가 감소하기 때문이다.

알레르기비염 환자의 체질분포 및 특이적 IgE 측정법(MAST CLA)의 임상적 의의 (Clinical Study of MAST CLA and Sasang Constitution in Allergic Rhinitis Patients)

  • 김찬중;김혜정;김윤범
    • 한방안이비인후피부과학회지
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    • 제15권2호
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    • pp.210-219
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    • 2002
  • Background and Objectives The diagnosis of allergic rhinitis includes detailed clinical history, physical examination and the use of either in vivo or vitro tests for relevant allergens. Skin test has been used the most commonly. Recently MAST CLA is used for determination of serum spcecific IgE, This study attempted to find out the distribution of Sasang Constitution and to compare the MAST CLA with skin tests in allergic rhinitis patients. Methods Skin tests, MAST CLA and Sasang Constitution study were performed for 35 allergic rhinitis patients who visited Kyunghee Oriental Medical Center from Sept. 2001 to Nov. 2001. Results 1. The ratio between male and female was 1:1.5. the peak age was the thirties(42.9$\%$) 2. 45.7$\%$ of patients had family history of allergic diseases and allergic rhinitis was the most common. 3. 51.4$\%$ of patients lived in A.P.T. and in preference of cool and warm, 54.3$\%$ of patients prefered both of cool and warm. 4. Among 24 cases who were consulted to dept. of Sasang, 45.8$\%$ was Taeumin. 5. 65.7$\%$ of patients reacted positive to skin test and the common offending allergen was D. pteronyssinus(82.6$\%$). 6. 25.7$\%$ of patients reacted positive to MAST CLA and the common offending allergen was D. farinae(88.9$\%$). 7. Among 22 cases who was performed skin test and MAST CLA the sensivity and specificity of MAST CLA was 27.4$\%$ and 94.9$\%$. There was significant correlations between MAST CLA and skin test(p=0.005, r=0.574, 1, spearman correlation coefficienct).

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Visualization of Epidermis and Dermal Cells in ex vivo Human Skin Using the Confocal and Two-photon Microscopy

  • Choi, Sang-Hoon;Kim, Wi-Han;Lee, Yong-Joong;Lee, Ho;Lee, Weon-Ju;Yang, Jung-Dug;Shim, Jong-Won;Kim, Jin-Woong
    • Journal of the Optical Society of Korea
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    • 제15권1호
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    • pp.61-67
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    • 2011
  • The confocal laser scanning microscopy and two-photon microscopy was implemented based on a single laser source and an objective lens. We imaged and compared the morphology of identical sites of ex vivo human skin using both microscopes. The back-scattering emission from the sample provided the contrast for the confocal microscopy. The intrinsic autofluorescence and the second harmonic generation were used as the luminescence source for the two-photon microscopy. The wavelength of the Ti:Sapphire laser was tuned at 710 nm, which corresponds to the excitation peak of NADH and FAD in skin tissue. The various cell layers in the epidermis and the papillary dermis were clearly distinguished by both imaging modalities. The two-photon microscopy more clearly visualized the intercellular region and the nucleus of the cell compared to the confocal microscopy. The fibrous structures in the dermis were more clearly resolved by the confocal microscopy. Numerous cells in papillary dermal layer, as deep as $100\;{\mu}m$, were observed in both CLSM and two-photon microscopy. While most previous studies focused on fibrous structure imaging (collagen and elastin fiber) in the dermis, we demonstrated that the combined imaging with the CLSM and two-photon microscopy can be applied for the non-invasive study of the population, distribution and metabolism of papillary dermal cells in skin.