• 제목/요약/키워드: mass

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스트로크 포화를 고려한 직렬 복합형 감쇠기의 비선형 제어 (Nonlinear Control of Cascade Hybrid Mass Dampers considering Stroke Saturation)

  • 민경원;황성호;김성춘;호경찬;김인수
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 가을 학술발표회논문집
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    • pp.377-386
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    • 2000
  • Hybrid mass dampers consist of passive tuned mass dampers and active mass dampers. They have the advantage that passive tuned mass dampers are still operated even when active mass dampers are stopped by excessive disturbances or power failure. This paper begins first with the comparative analysis of tuned mass dampers, hybrid mass dampers, and active mass dampers. Next more detailed study is carried out on the hybrid mass dampers: cascade hybrid mass dampers (CHMD) and active tuned mass dampers (ATMD). CHMD is regarded as more reasonable device because of its lighter active mass than ATMD's. However CHMD can not neglect stroke saturation problem caused by the length limitation of active damper mass. We compensate the saturation problem with nonlinear restoring force. The restoring force is calculated based on the states and phases of active mass dampers and added to the control force. It is shown that the presented compensation method prevents CHMD from saturation behavior without apparent changes of control force and responses compared to those in case of not considering the saturation problem.

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High-Throughput Active Compound Discovery using Correlations between Activity and Mass Profiles

  • Park, Kyu-Hwan;Yoon, Kyo-Joong;Kwon, Kyung-Hoon;Kim, Hyun-Sik
    • Mass Spectrometry Letters
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    • 제1권1호
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    • pp.13-16
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    • 2010
  • The active components in a plant extract can be represented as mass profiles. We introduce here a new, multi-compound discovery method known as Scaling of Correlations between Activity and Mass Profiles (SCAMP). In this method, a correlation coefficient is used to quantify similarities between the extract activity and mass profiles. The method was evaluated by first measuring the anti-oxidation activity of eleven fractions of an Astragali Radix extract using DPPH assays. Next, 15 T Fouriertransform ion cyclotron resonance (FT-ICR) MS was employed to generate mass profiles of the eleven fractions. A comparison of correlation coefficients indicated two compounds at m/z 285.076 and 286.076 that were strong antioxidants. Principal component analyses of these profiles yielded the same result. FT-ICR MS, which offers a mass resolving power of 500,000, was used to discern isotopic fine structures and indicated that the molecular formula corresponding to the peak at m/z 285.076 was $C_{16}H_{13}O_5$. SCAMP in combination with high-resolution MS can be applied to any type of mixture to study pharmacological activity and is a powerful tool for active compound discovery in plant extract studies.

Mass constraints of coronal mass ejection plasmas observed in EUV and X-ray passbands

  • 이진이
    • 천문학회보
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    • 제36권1호
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    • pp.39.1-39.1
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    • 2011
  • Coronal mass ejection (CME) plasmas have been observed in EUV and X-ray passbands as well as in white light. Mass of CME has been determined using polarized brightness observed by the Large Angle and Spectrometric Coronagraph Experiment (LASCO) on board Solar and Heliospheric Observatory (SOHO). Therefore, this mass obtained from the LASCO observation indicates the total CME mass. However, the mass of CME plasma in different temperatures can be determined in EUV and X-ray passbands using observations by SOHO/EIT, STEREO/EUVI, and Hinode/XRT. Prominence/CME plasmas have been observed as absorption or emission features in EUV and X-ray passbands. The absorption features provide a lower limit to cold mass. In addition, the emission features provide an upper limit to the mass of plasmas in temperature ranges of EUV and X-ray. We determine the mass constraints using the emission measure obtained by assuming the prominence/CME structures. This work will address the mass constraints of hot and cold plasmas in CMEs, comparing to total CME mass.

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Unusual Applications of Kendrick Plots: Recalibration and Tolerance

  • Thierry N. J. Fouquet;Orlando Cabarcos
    • Mass Spectrometry Letters
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    • 제14권4호
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    • pp.173-177
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    • 2023
  • Kendrick plots offer an alternative visualization of mass spectral data which reveals ion series and patterning by turning a mass spectrum into a map, plotting the fractional mass (wrongly called mass defect) as a function of mass-to-charge ratios and ion abundances. Although routinely used for polymer mass spectrometry, two unreported applications of these Kendrick plots are proposed using the program "kendo2": the graphical recalibration of a mass spectrum via the simulation of a theoretical fractional mass and a multi-segment fit; and the rapid evaluation of scan-to-scan variation of accurate mass measurements used as tolerances for the blank subtraction of UPLC-MS data files. Both applications are compatible with any type of high-resolution MS data including LC/GC-MS(/MS).

정상 성인의 신체조성과 폐 기능의 연관성 (Correlation between Body Composition and Lung Function in Healthy Adults)

  • 김현승;조성현
    • 대한통합의학회지
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    • 제8권2호
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    • pp.53-61
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    • 2020
  • Purpose : We investigated the correlation between body composition and lung function in healthy adults. Methods : This study included 204 healthy adults in whom all measurements were obtained once, and all data were analyzed using the SPSS software for Windows, version 22.0. Pearson's correlation analysis was performed to determine the correlation between body composition (represented by the total body water, protein mass, soft lean mass, mineral mass, basal metabolic rate, fat-free mass, skeletal muscle mass, and body fat percentage) and lung function (represented by the forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], the FEV1/FVC ratio, maximum voluntary ventilation [MVV], maximum expiratory pressure [MEP], and the maximum inspiratory pressure [MIP]). All measurements were obtained by two investigators to improve reliability. A significance level of α=.05 was used to verify statistical significance. Results : Among the lung function measurements obtained in both men and women, the FVC, FEV1, MVV, and MIP were positively correlated with the total body water, protein mass, soft lean mass, mineral mass, basal metabolic rate, fat-free mass, and skeletal muscle mass in men (p<.05). The FEV1/FVC ratio was negatively correlated with the total body water, soft lean mass, mineral mass, basal metabolic rate, fat-free mass and the body fat percentage (p<.05). Notably, the FVC, FEV1, and MVV were positively correlated with the total body water, protein mass, soft lean mass, mineral mass, basal metabolic rate, fat-free mass, and skeletal muscle mass in women (p<.05). Conclusion : This study showed a significant correlation between body composition and lung function in healthy adults. In combination with future studies on lung function, our results can provide objective evidence regarding the importance of prevention of lung disease, and our data can be utilized in rehabilitation programs for patients with respiratory diseases.

Association between body composition parameters and non-specific low back pain in sedentary workers

  • Kim, Wondeuk;Park, Dongchun;Shin, Doochul
    • Physical Therapy Rehabilitation Science
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    • 제10권1호
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    • pp.64-68
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    • 2021
  • Objective: In clinical practice, there are a lot of exercise to reduce body weight or reduce the amount of body fat in order to solve back pain. However, many studies have contradicted the relationship between back pain and weight or body fat mass. The purpose of this study was to investigate the relationship between fat mass, body mass index and low back pain of office worker. Design: Crossed-sectional study Methods: Among the white-collar workers diagnosed with non-specific back pain by doctors, subjects who were not included in the exclusion criteria were selected to measure the subject's body fat mass, body mass index, pain intensity, and disability index due to back pain. The NPRS was used for the intensity of back pain of office workers, and the ODI was used for the degree of disability due to back pain. A body composition analyzer was used to measure the body fat mass and body mass index of white-collar workers. Results: There was no significant difference between the two groups in the comparison between the normal group and the excessive group according to the criteria of fat mass and body mass index. In the correlation analysis of fat mass, body mass index, pain intensity, and disability index, it was found that there was a significant correlation between fat mass and body mass index. However, neither fat mass nor body mass index had a significant correlation with pain intensity and disability index. Conclusions: The fat mass and body mass index of office worker do not affect low back pain.

기체연료 엔진에서 공연비제어를 위한 흡입공기량 추정 (Estimation of Inlet Air Mass Flow for Air-Fuel Raito Control of Gaseous-Fuel Engines)

  • 심한섭;이강윤;선우명호;송창섭
    • 한국자동차공학회논문집
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    • 제9권5호
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    • pp.131-139
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    • 2001
  • Highly accurate control of the air-fuel ratio is important to reduce exhaust gas emissions of the gaseous-fuel engines. In order to achieve this purpose, inlet air mass flow must be measured exactly, and precise engine models are necessary to design engine control systems. In this paper, the effects of water vapor and gaseous fuel that change the air mass flow are studied. The effective air mass ratio is defined as the air mass flow divided by the mixture mass flow, and also it is applied to the estimation of the inlet air mass flow. The presence of the gaseous fuel and the water vapor in the mixture reduces the air partial pressure and the effective air mass ratio of the gaseous-fuel engines. The Experimental results for an LPG engine show that the estimation of the inlet ai mass flow based upon the effective air mass ratio is more accurate than that of the normal air mass flow.

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12주저항트레이닝 운동시 천연단백질과 분리유청단백질 섭취의 차이가 근육량 및 신체구성에 미치는 영향 (The Effect of the Difference Between Natural Protein and Whey Protein Intake During the 12 weeks of Resistance Training Exercise on Changes in Solt Lean Mass and Body Composltion)

  • 박원덕
    • 수산해양교육연구
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    • 제28권5호
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    • pp.1220-1230
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    • 2016
  • The purpose of this study is to investigate the effect of 20s university student bodybuilders' protein intake differences with resistant exercise(weight training) by 12 weeks on solt lean mass and body composltion. Natural protein(Chicken breast meat) intake group and Whey protein isolates(WPI) intake group are the experimental groups. Conventional meal intake group is the control group. This study proposes a efficient protein diet for weight training. The results were as follows. In the experimental group(natural protein intake), muscle mass and lean body mass was significantly increased, but body fat percentage was significantly decreased. In the experimental group(WPI intake), muscle mass and lean body mass was significantly increased, but body fat percentage was significantly decreased. In the control group(conventional meal intake), muscle mass and lean body mass was insignificantly increased, but body fat percentage was insignificantly decreased. In addition, there was not a significant difference among intake groups, and also not a differentiated effect between natural protein and WPI intake. In conclusion, natural protein and WPI made muscle mass and lean body mass rise, body fat percentage reduced effectively. Only WPI intake(without natural protein intake) was the efficient mean to increase muscle mass and lean body mass, and to decrease body fat percentage.