• 제목/요약/키워드: volume measurement

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기체용적계를 이용한 분동식 압력계용 기준분동의 새로운 부피측정 방법 (New Method of Volume Measurement for Reference Weights of a Pressure Balance Using a Gas Pycnometer)

  • 이용재;이우갑;모하메드;박연규;오재윤
    • 한국진공학회지
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    • 제22권5호
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    • pp.231-237
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    • 2013
  • 본 연구에서는 분동식 기준압력계의 기준분동(reference weight)의 부피를 측정하는 새로운 측정방법인 기체용적계(gas pycnometer) 측정방법을 제안하였다. 제안된 측정방법에 의한 측정결과로서 기준분동 1 kg, 2 kg, 5 kg에 대한 부피 측정불확도는 신뢰수준 95%에서 0.2%를 나타내었다. 기체용적계의 주요 장치는 샘플용기와 팽창용기, 정밀압력계, 정밀온도계, 진공펌프로 구성되며, 측정 원리는 일정한 용기 내에 들어 있는 일정한 양의 기체의 압력과 부피는 서로 반비례한다는 보일(boyle's law)의 법칙을 용용하였다. 본 결과는 현재까지 문헌이나 제조사로부터 기준분동 재질에 대한 밀도값을 적용하여 오던 것을 기준분동의 부피를 직접 측정하여 밀도값을 적용함으로서 압력기준기의 압력 기준값에 대한 국가측정표준의 신뢰도 향상에 기여될 것이다.

전력케이블내 반도전 재료의 전기적 및 기계적 특성; 체적저항과 Stress-Strain 측정 (Electrical and Mechanical Properties of Semiconductive Shield in Power Cable; Volume Resistivity and Stress-Strain Measurement)

  • 이경용;양종석;최용성;박대희
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제54권2호
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    • pp.45-50
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    • 2005
  • To improve mean-life and reliability of power cable, in this study, we have investigated electrical properties and stress-strain showing by changing the content of carbon black that is semiconductive additives for underground power transmission. Specimens were made of sheet form with the nine of specimens for measurement. Volume resistivity of specimens was measured by volume resistivity meter after 10 minutes in the pre-heated oven of both 25±1 [℃] and 90±1 [℃]. And stress-strain of specimens was measured by TENSOMETER 2000. A speed of measurement was 200[mm/min], ranges of stress and strain were 400[Kgf/㎠] and 600[%]. In addition tests of stress-strain were progressed by aging specimens in air oven. From this experimental results, volume resistivity was high according to increasing the content of carbon black. And yield stress was increased, while strain was decreased according to increasing the content of carbon black. And stress-strain were decreased some after aging because of oxidation reaction of chemical defect. We could know EEA was excellent more than other specimens from above experimental results.

레이저 및 열전대를 이용한 동축류 확산화염에서의 매연입자 측정에 관한 연구 (A Study on the Soot Particle Measurement in Co-Flow Diffusion Flame Using a Laser Diagnostics and a Thermocouple)

  • 한용택;이기형;이원남
    • 대한기계학회논문집B
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    • 제28권7호
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    • pp.863-870
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    • 2004
  • The temperature and soot particle measurement technique in a laminar diffusion flame has been studied to investigate the characteristics of soot particle with temperature using a co-flow burner. The temperature distribution in the flame were measured by rapid insertion of a R-type thermocouple and the soot particles by LEM/LIS techniques. In these measurement, soot volume fraction, number density and soot diameters were analyzed experimentally. As a results, the spacial distributions of particle volume fraction, soot diameter, and number density are mapped throughout the flame using the Rayleigh theory for the scattering of light by particles. A laser extinction method was used to measure the soot volume fraction and laser induced scattering method was used to measure the soot particle diameter and number density. Also, we measured temperature without the effect of soot particles attached to the thermocouple junction, which is close to the nozzle. In this result, we found that upstream zone has a unstable flowing in co-flow diffusion flame and the y-axis temperature of flame has a uniform temperature distribution in the most soot volume fraction zone.

레이저 및 열전대를 이용한 동축류 확산화염에서의 매연입자 측정에 관한 연구 (A Study on the Soot Particle Measurement in Co-flow Diffusion Flame Using a Laser Diagnostics and a Thermocouple)

  • 한용택;이기형;이원남
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1267-1273
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    • 2004
  • The temperature and soot particle measurement technique in a laminar diffusion flame have been studied to investigate the characteristics of soot particle with temperature using a co-flow burner. The temperature distributions in the flame were measured by rapid insertion of a R-type thermocouple and the soot particles were detected were detected by LEM/LIS techniques. In these measurement, soot volume fraction, number density and soot diameters were analyzed experimentally. As a results, the spacial distributions of particle volume fraction, soot diameter, and number density are mapped throughout the flame using the Rayleigh theory for the scattering of light by absorbing particles. A laser extinction method was used to measure the soot volume fraction and Laser induced scattering method was used to measure the soot particle diameter and number density. Also, we measured temperature without the effect of soot particles attached to the thermocouple junction, which is close to the nozzle. In this result, we found that upstream zone has a unstable flowing in co-flow diffusion flame and the y-axis temperature of flame has a uniform temperature distribution in the most soot volume fraction zone.

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경직장초음파를 이용한 전립선 볼륨측정 시의 위치 연구: 전립선모형 제작과 실험 (Location Studies of Prostate Volume Measurement by using Transrectal Ultrasonography: Experimental Study by Self-Produced Prostate Phantom)

  • 김연민;윤준;변일균;이후민;김형균
    • 대한방사선기술학회지:방사선기술과학
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    • 제38권4호
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    • pp.437-442
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    • 2015
  • 전립선의 정확한 볼륨측정은 전립선암과 전립선비대의 진단, 치료 결정 및 예후 판정에 있어서 중요한 역할을 한다. 또한, 전립선암 선별검사에 사용하고 있는 혈청전립선특이항원(serum prostate-specific antigen)은 전립선의 볼륨과 서로 높은 상관관계를 보이기 때문에 이를 평가하기 위해서는 정확한 볼륨을 아는 것이 중요하다. 기존의 전립선 측정법이 다양하게 제시되고 있으나 전립선 모형 별 측정법에 대한 연구는 없었다. 본 연구에서는 다양한 모형의 팬텀을 제작하고 초음파를 이용하여 볼륨을 알아본 후 모형 별 측정위치를 찾아 새로운 측정방법을 제시하고자 한다. 초음파 검사를 통해 특징적인 전립선 모양 6개를 선정하였다. 이를 횡단과 종단영상을 참고하여 전립선 모형 6개를 제작하였다. 최적의 측정위치에서 각각 3회씩 반복측정 후 실제볼륨과 측정볼륨간의 유의성을 알아보기 위하여 Wilcoxon 부호순위 검정을 실시하였다. p값은 0.05이하일 때 유의한 것으로 정하였다. Axial 영상에서 돌출부위를 제외하고 안쪽으로 두고, Longitudinal 영상에서는 base와 apex의 오목한 부분에 측정 점을 놓았을 때 실제 전립선 크기와 일치도가 높았다. 실제볼륨과 측정볼륨간의 유의성은 p값 0.156으로 통계적으로 유의한 차이가 없었다. 전립선 axial 영상에서 전립선 이행대의 돌출이 심할 경우 돌출부위를 배제하고 측정하는 것이 실제 볼륨에 가까웠다. 또한 longitudinal영상에서는 apex부분이 가늘고 길어질 경우에 끝부분이 아닌 안쪽으로 측정 점을 잡아 그 점을 기준으로 타원을 그려 볼륨을 측정하는 것이 실제 볼륨에 가장 가까웠다.

저가형 UAV를 이용한 소규모지역의 토량 측정 (Earth-Volume Measurement of Small Area Using Low-cost UAV)

  • 성지훈;한유경;이원희
    • 한국측량학회지
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    • 제36권4호
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    • pp.279-286
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    • 2018
  • 토목공사에서 토량 측정은 합리적인 공사비 산정에 중요한 요소 중 하나이다. 이전까지 토목공사 현장의 정보를 얻기 위해서 GPS 또는 토탈스테이션을 이용하는 방법을 사용해 왔지만 이러한 방식은 접근이 어려운 지역에는 측정에 무리가 있다. 이에 본 연구에서는 무인항공기를 이용하여 토량을 측정하고자 한다. 경상북도 상주시에 위치한 농촌용수개발사업 저수지 공사현장을 연구대상지로 선정하였으며, GPS를 이용한 측량을 기준으로 하여 토탈스테이션 그리고 UAV를 이용한 측량의 정확도와 측정시간을 비교하는 연구를 진행하였다. GPS를 이용하여 취득한 토량은 $147,286.79m^3$으로 나타났고, 토탈스테이션은 $141,594.07m^3$으로 GPS를 이용하여 구한 토량을 기준으로 96.13% 정확도를 보였다. 그리고 UAV는 GCP를 측정하지 않고 진행하였을 때 $143,997.05m^3$, GCP가 4개일때 $147,251.71m^3$ 그리고 GCP가 7개일 때 $146,963.81m^3$로 나타났고, 각각 GPS로 측량한 토량과 비교하여 97.77%, 99.98%, 99.78%의 정확도를 보였다. 이를 통하여 UAV를 이용한 토량 산정을 실제 현장에서 사용할 수 있음을 확인할 수 있었다.

복부에서 측정하는 일회 호흡용적의 정확도 평가 (Accuracy Evaluation of Tidal Volume Measured on the Abdomen)

  • 이인광;김성식;장종찬;김군진;김경아;이태수;차은종
    • 전기학회논문지
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    • 제57권7호
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    • pp.1298-1303
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    • 2008
  • Respiration is induced by muscular contraction of the chest and abdomen, resulting in the abdominal volume change. Thus, continuous measurement of the abdominal dimension enables to monitor breathing activity. Conductive rubber cord has been previously introduced and tested to develop wearable application for respiratory measurements. This study implemented respiratory monitoring system with the conductive rubber cord in the patient's pants in purpose of quantitative estimation of tidal volume. Air mixed with $0{\sim}5%$ $CO_2$ was inhaled and the respiratory air flow rate, abdominal dimension change, and end tidal $CO_2$ concentration were simultaneously measured in steady state. $CO_2$ inhalation significantly increased the tidal volume in normal physiological state with the subject unawared. The tidal volume estimated from the abdominal dimension change linearly correlated with the tidal volume measured by a pneumotachometer with a correlation coefficient of 0.88. Customized calibration for each subject resulted in relative errors less than 10%. Therefore, the tidal volume was accurately estimated by measuring the abdominal dimension change.

백설기 조리법의 표준화를 위한 조리과학적 연구(I) (Scientific Study for the Standardization of the Preparation Methods for Paeksolgi(I))

  • 김기숙
    • 대한가정학회지
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    • 제25권2호
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    • pp.79-87
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    • 1987
  • Paeksolgi is a typical Korean rice cake made by steaming rice powder added sugar, water and salt. This study attempted to clarify the factors which affect the textural characteristics, and to examine the effects of various steaming time and volume of adding water on sensory characteristics and Instron measurement on textures of Paeksolgi. Evaluation was conducted through sensory evaluation and objective evaluation. The results were summarized as follows. 1. In the preparation, the significant factors were soaking time, volume of sugar, and the interaction between soaking time and volume of adding water. And, Kind of sweetener, volume of adding water, steaming time, condition of powder, and the interaction between soaking time and steaming time, and between soaking time and volume of adding water, and between kind of sweetener and condition of powder, and between steaming time and volume of sugar were the significant factors which affected the textural characteristics of Paeksolgi. 2. In sensory evaluation on the various steaming time and volume of adding water, Paeksolgi made by steaming rice powder added water of 10% for 30 min. showed the most favorite tendency on the overall quality. The results of Instron measurement indicated that hardness, gumminess and chewiness tended to decrease as volume of adding water increased in same steaming time.

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Effectiveness of Computed Tomography for Blow-out Fracture

  • Rhee, Seung-Hyun;Kim, Tae-Seup;Song, Jae-Min;Shin, Sang-Hoon;Lee, Jae-Yeol
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제36권6호
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    • pp.273-279
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    • 2014
  • Purpose: This study assessed the association between eye symptoms (enophthalmos or diplopia) and site of damage, volume, deviated inferior rectus muscle (IRM) and type of fracture with computed tomography (CT). The intent is to anticipate the prognosis of orbital trauma at initial diagnosis. Methods: Forty-five patients were diagnosed with fractures of the inferior wall of one orbit. Fracture area, volume of displaced tissue, deviated IRM, and type of fracture were evaluated from coronal CT by one investigator. The association of those variables with the occurrence of eye symptoms (diplopia and enophthalmos) was assessed. Results: Of 45 patients, 27 were symptom-free (Group A) and 18 had symptoms (Group B) of enophthalmos and/or diplopia. In Group B, 12 had diplopia, one was enophthalmos, and five had both. By CT measurement, group A mean area was $192.6mm^2$ and the mean volume was $673.2mm^3$. Group B area was $316.2mm^2$ and volume was $1,710.6mm^3$. The volume was more influential on symptom occurrence. Each patient was categorized into four grades depending on the location of IRM. Symptom occurrence and higher grade were associated. Twenty-six patients had trap-door fracture (one side, attached to the fracture), and 19 had punched-out fracture (both sides detached). The punched-out fracture was more strongly associated with symptoms and had statistically significantly higher area and volume. Conclusion: In orbital trauma, measurement of fracture area and volume, evaluation of the deviated IRM and classification of the fracture type by coronal CT can effectively predict prognosis and surgical indication.

Method of tumor volume evaluation using magnetic resonance imaging for outcome prediction in cervical cancer treated with concurrent chemotherapy and radiotherapy

  • Kim, Hun-Jung;Kim, Woo-Chul
    • Radiation Oncology Journal
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    • 제30권2호
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    • pp.70-77
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    • 2012
  • Purpose: To evaluate the patterns of tumor shape and to compare tumor volume derived from simple diameter-based ellipsoid measurement with that derived from tracing the entire tumor contour using region of interest (ROI)-based 3D volumetry with respect to the prediction outcome in cervical cancer patients treated with concurrent chemotherapy and radiotherapy. Materials and Methods: Magnetic resonance imaging was performed in 98 patients with cervical cancer (stage IB-IIIB). The tumor shape was classified into two categories: ellipsoid and non-ellipsoid shape. ROI-based volumetry was derived from each magnetic resonance slice on the work station. For the diameter-based surrogate "ellipsoid volume," the three orthogonal diameters were measured to calculate volume as an ellipsoid. Results: The more than half of tumor (55.1%) had a non-ellipsoid configuration. The predictions for outcome were consistent between two volume groups, with overall survival of 93.6% and 87.7% for small tumor (<20 mL), 62.9% and 69.1% for intermediate-size tumor (20-39 mL), and 14.5% and 16.7% for large tumors (${\geq}$40 mL) using ROI and diameter based measurement, respectively. Disease-free survival was 93.8% and 90.6% for small tumor, 54.3% and 62.7% for intermediate-size tumor, and 13.7% and 10.3% for large tumor using ROI and diameter based method, respectively. Differences in outcome between size groups were statistically significant, and the differences in outcome predicted by the tumor volume by two different methods. Conclusion: Our data suggested that large numbers of cervical cancers are not ellipsoid. However, simple diameter-based tumor volume measurement appears to be useful in comparison with ROI-based volumetry for predicting outcome in cervical cancer patients.