• Title/Summary/Keyword: Stress signals

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Structural health monitoring using piezoceramic transducers as strain gauges and acoustic emission sensors simultaneously

  • Huo, Linsheng;Li, Xu;Chen, Dongdong;Li, Hongnan
    • Computers and Concrete
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    • v.20 no.5
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    • pp.595-603
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    • 2017
  • Piezoceramic transducers have been widely used in the health monitoring of civil structures. However, in most cases, they are used as sensors either to measure strain or receive stress waves. This paper proposes a method of using piezoelectric transducers as strain gauges and acoustic emission (AE) sensors simultaneously. The signals received by piezoceramic transducers are decomposed into different frequency components for various analysis purposes. The low-frequency signals are used to measure strain, whereas the high-frequency signals are used as acoustic emission signal associated with local damage. The b-value theory is used to process the AE signal in piezoceramic transducers. The proposed method was applied in the bending failure experiments of two reinforced concrete beams to verify its feasibility. The results showed that the extracted low-frequency signals from the piezoceramic transducers had good agreement with that from the strain gauge, and the processed high-frequency signal from piezoceramic transducers as AE could indicate the local damage to concrete. The experimental results verified the feasibly of structural health monitoring using piezoceramic transducers as strain gauges and AE sensors simultaneously, which can advance their application in civil engineering.

Measurement and Analysis of Rodent Biological Signals using Telemetry System (원격측정장치를 이용한 설치류의 생체신호 측정 및 분석)

  • Kim, Chang-Hwan;Hur, Gyeong-Haeng
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.6
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    • pp.1159-1165
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    • 2011
  • Telemetry techniques of rats have been used for assessing safety pharmacology of drugs and chemicals. Biological signals including blood pressure and heart rate measured under anesthesia were significantly different from those obtained under normal conditions. The stress of restraint in awake animals can also affect the accuracy of physiological evaluation. This paper details the surgery required to allow key cardiovascular parameters to be determined. The telemetric measurement of cardiovascular parameters such as blood pressure, heart rate, electrocardiograph(ECG) established. We carried out the continuous monitoring of cardiovascular parameters using the telemetry system in F344 rats. During the measurement, no significant changes were observed in the heart rate and blood pressure. ECG signals and body temperature were also constant during the measurement of biological signals. With the results of this study, we conclude that this telemetry system can be applied usefully for the assesment of biological parameters in the rats.

Study on the Verification of Healing Effect through Brain and Pulse Wave Analyses before and after Forest Walking (산림 산책 전후 뇌파 및 맥파 분석을 통한 치유효과 검증 연구)

  • Min-Su Kim;Jung-Hun Yeum
    • Journal of Environmental Science International
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    • v.33 no.4
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    • pp.249-256
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    • 2024
  • This study aimed to verify the healing effect through brain and pulse wave analyses before and after a forest walk to the university students. Bio-signals of brain and pulse waves were measured using Omnifit Mindcare. After analyzing four brain wave items such as concentration and four pulse wave items such as heart health, it is identified that the stress level of university students was higher than that of the general public, and the brain stress level was approached to the normal range for 19 people with clear improvement. For pulse waves, a statistically significant decrease in sympathetic nerve activity (%) was confirmed. Although the slight fluctuations within the normal range were caused by short term and individual differences, it showed that the forest walking is partially effect on the relieving stress.

Evaluation on the stress using HRV according to elapsed time of MRI noise (HRV를 이용한 자기공명영상 소음의 시간 변화에 따른 스트레스 평가)

  • Ye, Soo-Young;Kim, Dong-Hyun
    • Journal of the Institute of Convergence Signal Processing
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    • v.16 no.2
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    • pp.50-55
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    • 2015
  • The noise of MRI shooting is 100dB loud and has an intensive psychological and physiological influences on the human body. ECG signals were measured by experimental methods, while wearing earplugs for 15 minutes in the stable state. Then the ECG signals were measured for 30 minutes while listening to about 100dB of sound in a MRI equipment. In this study, the heart rate variability of men and women was analyzed according to the MRI noise stress level through the frequency analysis. As the MRI noise level is about 100dB, HRV analysis resulted in an imbalance between the sympathetic and parasympathetic. During the period from the resting state up to 10 minutes, the maximum stress state was shown. This study will encourage MRI workers to take interests in hearing protection for the patient and to make objective indicators about MRI noises.

Future Prospects for Industrial Application of Abscisic acid, a Stress-resistant Phytohormone (스트레스 내성 식물 호르몬인 앱시스산의 산업적 활용 전망)

  • Lee, Jeongho;Kim, Seunghee;Yoo, Hah Young
    • Korean Chemical Engineering Research
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    • v.58 no.4
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    • pp.514-523
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    • 2020
  • Plants are exposed to various types of stresses in their surroundings, and stress-resistant and regulatory proteins are produced as defense mechanisms. Abscisic acid is well known for its important role in stress signals as a phytohormone and is also involved in the physiological reactions of plants such as leaf senescence and seed dormancy. In particular, it has been found to perform a variety of functions in other biological systems, such as animals and microalgae, not plants. In this review, the biosynthesis and signaling process of abscisic acid and its function were investigated and the future prospects for the industrial application of abscisic acid in various biotechnologies, including agriculture, biomedical and industrial biotechnology, have been proposed based on study of emerging applications such as increased crop yields, disease treatment development and bioenergy production.

A NOTE ON NEW METALLIC BONDING ORBITAL

  • Oh, Hung-Kuk
    • Proceedings of the Materials Research Society of Korea Conference
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    • 1994.11a
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    • pp.156-162
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    • 1994
  • The existence of the elastic anisotropic channeling is based on the experimental evidences. The rotating electron pairs orbits play the role of basic bonding orbitals. The abnormal signals from ligand domain and train-membrane in cancer cell, Deformation in fatigue and creep at low stress, con duction, superconduction and semiconduction are all from the new metallic bonding orbital.

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Computational Identification and Comparative Genomic Analysis of Soybean Oxidative Stress-Related Genes

  • Arti, Sharma;Mun, Bong-Gyu;Yun, Byung-Wook
    • Current Research on Agriculture and Life Sciences
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    • v.32 no.1
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    • pp.43-52
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    • 2014
  • Reactive oxygen and nitrogen species (ROS and RNS, respectively) are messengers that carry signals to alter the redox state in order to activate plant responses and other physiological processes, such as differentiation, aging, senescence, and pathogen defense. Quite a large number of genes are involved in this signaling and lead to oxidative stress in plants. Although the role of ROS/RNS during stress conditions is well documented, a comprehensive list of genes and comparative study of these genes has not yet been completed. Accordingly, the in silico identification of oxidative stress-related genes was performed for soybeans and Arabidopsis. These genes were also studied in relation to multiple domain prediction. The presence of domains like dehydogenase and ATPase suggests that these genes are involved in various metabolic processes, as well as the transportation of ions under optimal environmental conditions. In addition to a sequence analysis, a phylogenetic analysis was also performed to identify orthologous pairs among the soybean and Arabidopsis oxidative stress-related genes based on neighbor joining. This study was also conducted with the objective of further understanding the complex molecular signaling mechanism in plants under various stress conditions.

Development of a System Observing Worker's Physiological Responses and 3-Dimensional Biomechanical Loads in the Task of Twisting While Lifting

  • Son, Hyun Mok;Seonwoo, Hoon;Kim, Jangho;Lim, KiTaek;Chung, Jong Hoon
    • Journal of Biosystems Engineering
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    • v.38 no.2
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    • pp.163-170
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    • 2013
  • Purpose: The purpose of this study is to provide analysis of physiological, biomechanical responses occurring from the operation to lifting or twist lifting task appears frequently in agricultural work. Methods: This study investigated the changes of physiological factors such as heart rate, heart rate variability (HRV) and biomechanical factors such as physical activity and kinetic analysis in the task of twisting at the waist while lifting. Results: Heart rates changed significantly with the workload. The result indicated that the workload of 2 kg was light intensity work, and the workload of 12 kg was hard intensity work. Physical activity increased as the workload increased both on wrist and waist. Besides, stress index of the worker increased with the workload. Dynamic load to herniated discs was analyzed using inertial sensor, and the angular acceleration and torque increased with the workload. The proposed measurement system can measure the recipient's physiological and physical signals in real-time and analyzed 3-dimensionally according to the variety of work load. Conclusions: The system we propose will be a new method to measure agricultural workers' multi-dimensional signals and analyze various farming tasks.

A Study on the Clinical Use of 7-zone-Diagnostic System (2) - the Comparative Analysis of the Rule and the Decipher for each Equipment - (7구역진단기의 임상응용에 대한 고찰 (2) - 각 제품에 따른 원리와 판독의 비교 -)

  • Song, Beom-Yong
    • Journal of Acupuncture Research
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    • v.23 no.5
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    • pp.11-21
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    • 2006
  • The 7-zone-diagnostic system(ABR-2000, BIO MEDIC 700Plus, CP-6000A, OMD 3000, VEGA-DFM 722) is a diagnostic device which applies pulse signals to predetermined bodily locations. Applying alternating positive and negative stress to tissues with positive and negative pulses first manifests itself as negative and positive wave forms. This system make a diagnosis of functional disorder or some typical organic diseases include stress of the mind or the body, and the energetic situation, reserves. We are known a disorder or disease throw the result charts. And these result represents various characteristic signals are assisted diagnosis and care. These result chart contains disorder flow wave forms and some valuable diagnostic hints or marks. But we have several various products for the 7-zone-diagnostic system. I think that we need the comparative analysis of the general rule and the decipher for each equipment. Because these letters(marks) each product are different, we necessary various plentiful research and suitable statistics in these points. And we must carry out many various research in the future.

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Backbone NMR Assignments of a Prokaryotic Molecular Chaperone, Hsp33 from Escherichia coli

  • Lee, Yoo-Sup;Won, Hyung-Sik
    • Journal of the Korean Magnetic Resonance Society
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    • v.16 no.2
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    • pp.172-184
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    • 2012
  • The prokaryotic molecular chaperone Hsp33 achieves its holdase activity upon response to oxidative stress particularly at elevated temperature. Despite many structural studies of Hsp33, which were conducted mainly by X-ray crystallography, the actual structures of the Hsp33 in solution remains controversial. Thus, we have initiated NMR study of the reduced, inactive Hsp33 monomer and backbone NMR assignments were obtained in the present study. Based on a series of triple resonance spectra measured on a triply isotope-[$^2H/^{13}C/^{15}N$]-labeled protein, sequence-specific assignments of the backbone amide signals observed in the 2D-[$^1H/^{15}N$]TROSY spectrum could be completed up to more than 96%. However, even considering the small portion of non-assigned resonances due to the lack of sequential connectivity, we confirmed that the total number of observed signals was quite smaller than that expected from the number of amino acid residues in Hsp33. Thus, it is postulated that peculiar dynamic properties would be involved in the solution structure of the inactive Hsp33 monomer. We expect that the present assignment data would eventually provide the most fundamental and important data for the progressing studies on the 3-dimensional structure and molecular dynamics of Hsp33, which are critical for understanding its activation process.