• Title/Summary/Keyword: measuring volume

Search Result 798, Processing Time 0.027 seconds

Beta particle energy spectra shift due to self-attenuation effects in environmental sources

  • Alton, Thomas Theakston;Monk, Stephen David;Cheneler, David
    • Nuclear Engineering and Technology
    • /
    • v.49 no.7
    • /
    • pp.1483-1488
    • /
    • 2017
  • In order to predict and control the environmental and health impacts of ionizing radiation in environmental sources such as groundwater, it is necessary to identify the radionuclides present. Beta-emitting radionuclides are frequently identified by measuring their characteristic energy spectra. The present work shows that self-attenuation effects from volume sources result in a geometry-dependent shift in the characteristic spectra, which needs to be taken into account in order to correctly identify the radionuclides present. These effects are shown to be compounded due to the subsequent shift in the photon spectra produced by the detector, in this case an inorganic solid scintillator ($CaF_2:Eu$) monitored using a silicon photomultiplier. Using tritiated water as an environmentally relevant, and notoriously difficult to monitor case study, analytical predictions for the shift in the energy spectra as a function of depth of source have been derived. These predictions have been validated using Geant4 simulations and experimental results measured using bespoke instrumentation.

Effects of metal catalysts on the characteristics of NO sensor using ZnO thin film as sensing material (금속 촉매가 ZnO 박막을 감지물질로 이용한 NO 센서의 특성에 미치는 영향)

  • Chung, Gwiy-Sang;Jeong, Jae-Min
    • Journal of Sensor Science and Technology
    • /
    • v.19 no.1
    • /
    • pp.58-61
    • /
    • 2010
  • This paper describes the fabrication and characteristics of NO sensor using ZnO thin film by RF magnetron sputter system. The sensitivity, working temperature, and response time of sputtered pure ZnO thin film and added catalysts such as Pt, Pd, Al, Ti on those films were measured and analyzed. The sensitivity of pure ZnO thin film at working temperature of $300^{\circ}C$ is 0.875 in NO gas concentration of 0.046 ppm. At same volume of the gas in chamber, measuring sensitivity of 1.87 at $250^{\circ}C$ was the case of Pt/ZnO thin film. The ZnO thin films added with catalyst materials were showed higher sensitivity, lower working temperature and faster adsorption characteristics to NO gas than pure ZnO thin film.

Study on Acoustic Characteristics of the Watermelon (수박의 음향특성에 관한 연구)

  • 김만수;최동수;이영희;조영길
    • Journal of Biosystems Engineering
    • /
    • v.23 no.1
    • /
    • pp.57-66
    • /
    • 1998
  • This study was conducted to investigate the relationships between parameters affecting internal quality of watermelon and its acoustic characteristics. The measuring and analyzing system was established to study the acoustic characteristics of watermelon. Algorithms for analyzing sound signals were developed. Sound signals which was detected with the microphone were filtered, and their spectrum was computed by means of the Fast Fourier Transform. As watermelon changed from the unripe stage to ripe, acoustic waves in time domain became complicated, and several components appeared in frequency domain. The correlationship was investigated between some parameters affecting internal quality of the watermelon and several peak frequencies. Results indicated that weight, density and sugar content had high correlations with several frequencies(the first peak frequency, the second peak frequency, and the third peak frequency). And the sugar content and the volume of the watermelon were highly correlated with the third peak frequency.

  • PDF

Irritable Larynx Syndrome with Dyspnea (호흡곤란을 동반하는 과민성 후두 증후군)

  • Ahn, Cheol Min
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
    • /
    • v.27 no.1
    • /
    • pp.21-24
    • /
    • 2016
  • An irritable larynx syndrome is characterized by a sudden episodic dyspnea and dysphonia that is difficult to diagnose, and patients are often treated unnecessarily and/or too much. A correct diagnosis can be made by monitoring the larynx closing in the reversed direction during inhalation and posterior chink with videolaryngoscopy and by measuring a decrease in air flow volume during inhalation with a lung function test. Patients can be effectively treated with thorough differential diagnosis. Medications targeting precipitating factors, physical therapy sessions to improve abnormal larynx movement, counseling to reduce patients'anxiety rising from dyspnea, and etc. can effectively alleviate symptoms.

  • PDF

DATA QUALITY AND COSTS IN MEASURING TIME-RELATED UNDEREMPLOYMENT IN KOREA

  • Kim Sulhee
    • Proceedings of the Korean Statistical Society Conference
    • /
    • 2000.11a
    • /
    • pp.97-104
    • /
    • 2000
  • Time-related underemployment exists when a person's employment is insufficient in terms of the volume of work. Two alternative definitions can be considered based on a longer-term view or a shorter-term view and these were designed into a single questionnaire. We conducted a pilot sample survey with about 6,000 respondents in Korea. The estimates of underemployment using the two definitions show some differences given the ages, genders, industrial areas and main activities of the respondents. A larger number of people could be identified as underemployed when the longer-term view is used than when the shorter-term view is used, but there is a greater cost associated with the former. The cost-benefit of the interviewers' time was investigated by multiple visits to households. Biases and costs are also analyzed using the results of the comparison of the decrease in non-responses with the increase in the costs for the interviews.

  • PDF

Chlorine Inhibition on the Denitrifying Activity of Activated Sludge Microorganisms (활성슬러지 미생물의 탈질 활성에 대한 염소의 저해)

  • Choi, Jin-Taek;Nam, Se-Yong
    • Journal of Environmental Health Sciences
    • /
    • v.33 no.4
    • /
    • pp.338-343
    • /
    • 2007
  • Chlorine inhibition on the denitrifing activity of activated sludge treating dairy wastewater was investigated in this study. Filamentous bulking was caused artificially by a sudden load of feed and monitored by measuring sludge volume index. In cases of the activated sludge and bulking sludge which were contacted with chlorine as $7.5\;mgCl_2/gVSS/day$ for bulking control, the decreases of specific denitrification of $32.2{\sim}40.4%\;and\;43.5{\sim}46.5%$ were shown in comparison to the control group which was not reacted with chlorine, respectively. In continuous operation, it was observed that the removal efficiency of total nitrogen was more susceptible to chlorine than the removal efficiency of total phosphorus.

Clinical Transcranial Doppler (임상 경두개 도플러 검사)

  • Kim, Jong-Soon;Ryoo, Jae-Kwan
    • Journal of Korean Physical Therapy Science
    • /
    • v.6 no.4
    • /
    • pp.153-165
    • /
    • 1999
  • The transcranial Doppler(TCD) is a technique for measuring blood flow velocity of intracranial and extarcranial arteries. This examination based on Doppler effect which was first formulated in 1842 by the Austrian physicist Christian Doppler. In 1982, Rune Aaslid first maked 2MHz pulsed probe and recording intracranial vessels with transcranially. There are six criteria utilized in gaining positive identification of the intracranial vessels. The six criteria are as follows l)acoustical windows 2)depth of sample volume 3)direction of flow 4)spatial relationship of ACA and MCA bifurcation 5)mean velocity and 6)response common carotid artery compression and/or oscillation test. The affected factors for TCD examination are angle of insonation, posture of subject, age, gender, hematocrit, metabolic factors, and cardiac output. Clinical application of TCD are detection of stenosis, occlusion, emboli, thrombsis in intracranial and extracranial arteries and evaluation of cerebral arterovenous malformation, collateral capacity in the circle of Willis, ischemia cerebrovascular disease, stroke patient and vertebrobasilar system.

  • PDF

The Effect of a Breathing Exercise Intervention on Pulmonary Function after Lung Lobectomy (폐절제술을 받은 환자의 호흡운동중재가 폐기능에 미치는 효과)

  • Jung, Kyung-Ju;Lee, Young-Sook
    • Asian Oncology Nursing
    • /
    • v.10 no.1
    • /
    • pp.95-102
    • /
    • 2010
  • Purpose: The aim of this study was to evaluate the effect of a breathing exercise intervention by measuring pulmonary function test (PFT) three times; preoperative, 3rd and 5th day after operation. Methods: This study was designed as a non-equivalent control group pretest-posttest design. A total of 55 patients with lung cancer were recruited from a Chonnam university hospital in Hawsun-gun, Korea from January to December 2008. Results: 'Forced Vital Capacity (FVC)' and 'Forced Expiratory Volume in 1 second $(FEV_1)$' were significantly improved in the experimental group than those in the control group (p<.05). Conclusion: Breathing exercise intervention was found to be effective in improving pulmonary function among lung cancer patients underwent lung lobectomy. Thus, the breathing exercise can be applied in hospitals and communities for patients with lung cancer as one of the nursing intervention modalities for their better postoperative rehabilitation.

An experimental study of Incompressible time based mass flow controller (비압축성 시간식 질량유량계의 특성에 관한 연구)

  • Chang, Young-Chul
    • Journal of the Semiconductor & Display Technology
    • /
    • v.7 no.3
    • /
    • pp.55-58
    • /
    • 2008
  • The objective of this research is to design, manufacture and test a mass flow controller capable of measuring compressible as well as incompressible fluid flows based on a 'bucket and stop-watch' method. The basic principle behind such a system is the measurement of time, where the time taken to fill and empty a bucket of known volume is measured. This device should be able to handle fluid flows in the range of 0.1 ml/min to 10 ml/min within an accuracy of ${\pm}$1%. For the flow meter to be able to compete with established designs, it must be not only comparable in cost and robustness, but also very accurate and reliable as well.

  • PDF

Intertester and Intratester Reliability of Tape Measurement on Lower Extremities (줄자를 이용한 하지부피 측정시 부위별 검사자간, 검사자내 신뢰도 측정)

  • Kim, Seng-Jung;Yang, Hoi-Song;Yi, Chung-Hwi
    • Physical Therapy Korea
    • /
    • v.7 no.1
    • /
    • pp.38-45
    • /
    • 2000
  • Tape measurement for evaluating edema is frequently used by clinicians. The primary purpose of this study is to determine the intertester and intratester reliability of tape measurement carried out by two physical therapists on lower extremities. The intertester and intratester reliability of six anatomical landmarks measurements were determined in six healthy subjects. The measurements were taken in five sessions by each tester. The intraclass correlation coefficients (2,1) were between .87 and .99 for intertester reliability. Intratester reliability was .93 and .99 for A tester and .82 and .99 for B tester. The average range of variation was .13 to .54 in six landmarks. The reliability of six volume measurements was very high. These results support the use tape measurement as a reliable tool for measuring limb girth.

  • PDF