• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.8
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• pp.1130-1133
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• 2021

In this paper, a miniaturized sensor interface circuit for the respiration detection system is proposed. Respiratory diagnosis is one of the main ways to predict various diseases. The proposed system consists of respiration detection sensor, temperature sensor, and interface circuits. Electrochemical type gas sensor using solid electrolytes is adopted for respiration detection. Proposed system performs sensing, amplification, analog-to-digital conversion, digital signal processing, and i2c communication. And also proposed system has a small form factor and low-cost characteristics through optimization and miniaturization of the circuit structure. Moreover, technique for sensor degradation compensation is introduced to obtain high accuracy. The size of proposed system is about 1.36 cm².

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2209-2213
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• 2011

When taking PET/CT, the distortion of the image happens due to the movement of a lesion with respiration. In this study, the experiment was conducted to see if the change in SUV value and distortion of the image could be somewhat corrected by comparing the image which was not compensated with that of the region of lung nodule, compensated with respiration compensation Plumonary Toolkit possessed by this hospital. The records of 17 patients with Lung cancer between May and August 2008. As the result of the experiment, Max SUV value increased by from 4.08% minimum to 43.10% maximum, and the average Max SUV value of lung nodule increased from 6.07 to 7.00(12.16%). In the case of respiration compensation PET/CT, the distortion of the image improved. As there was no significance in the comparison of SCC and Adenocarcinom respectively, though there was a statistically significant level(P<0.05) before and after respiration compensation in SCC-Adenocarcinoma, there was an effect in respiration compensation regardless of Cell types. As the result of the experiment, it was found out that the distortion of standard intake coefficient value and the image was compensated Therefore, the diagnosis of lung cancer and follow up will be able to help.

• Journal of Korea Multimedia Society
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• v.21 no.9
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• pp.1076-1089
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• 2018

Respiration is the process of moving air into and out of the lung. Respiration changes the temperature in the chamber while exchanging energy. Especially the temperature of the face. Respiration monitoring using an infrared camera measures the temperature change caused by breathing. The conventional method assumes that motion is not considered and measures respiration. These assumptions can not accurately measure the respiration rate when breathing moves. In addition, the respiration rate measurement is performed by counting the number of peaks of the breathing waveform by displaying the position of the peak in a specific window, and there is a disadvantage that the breathing rate can not be measured accurately. In this paper, we use KLT tracking and block matching to calibrate limited weak movements during breathing and extract respiration waveform. In order to increase the accuracy of the respiration rate, the position of the peak used in the breath calculation is calculated by converting from a single point to a high resolution. Through this process, the respiration signal could be extracted even in weak motion, and the respiration rate could be measured robustly even in various time windows.

• Investigative Magnetic Resonance Imaging
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• v.21 no.1
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• pp.28-33
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• 2017

Purpose: To investigate and compensate the effects of respiration-induced B0 variations on fat quantification of the bone marrow in the lumbar spine. Materials and Methods: Multi-echo gradient echo images with navigator echoes were obtained from eight healthy volunteers at 3T clinical scanner. Using navigator echo data, respiration-induced B0 variations were measured and compensated. Fat fraction maps were estimated using $T2^*$-IDEAL algorithm from the uncompensated and compensated images. For manually drawn bone marrow regions, the estimated B0 variations and the calculated fat fractions (before and after compensations) were analyzed. Results: An increase of temporal B0 variations from inferior level to superior levels was observed for all subjects. After compensation using navigator echo data, the effects of the B0 variations were reduced in gradient echo images. The calculated fat fractions show significant differences (P < 0.05) in L1 and L3 between the uncompensated and the compensated. Conclusion: The results of this study raise the need for considering respiration-induced B0 variations for accurate fat quantification using gradient echo images in the lumbar spine. The use of navigator echo data can be an effective way for the reduction of the effects of respiratory motion on the quantification.

• Investigative Magnetic Resonance Imaging
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• v.23 no.1
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• pp.38-45
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• 2019

Purpose: To demonstrate the high-resolution numerical simulation of the respiration-induced dynamic $B_0$ shift in the head using generalized susceptibility voxel convolution (gSVC). Materials and Methods: Previous dynamic $B_0$ simulation research has been limited to low-resolution numerical models due to the large computational demands of conventional Fourier-based $B_0$ calculation methods. Here, we show that a recently-proposed gSVC method can simulate dynamic $B_0$ maps from a realistic breathing human body model with high spatiotemporal resolution in a time-efficient manner. For a human body model, we used the Extended Cardiac And Torso (XCAT) phantom originally developed for computed tomography. The spatial resolution (voxel size) was kept isotropic and varied from 1 to 10 mm. We calculated $B_0$ maps in the brain of the model at 10 equally spaced points in a respiration cycle and analyzed the spatial gradients of each of them. The results were compared with experimental measurements in the literature. Results: The simulation predicted a maximum temporal variation of the $B_0$ shift in the brain of about 7 Hz at 7T. The magnitudes of the respiration-induced $B_0$ gradient in the x (right/left), y (anterior/posterior), and z (head/feet) directions determined by volumetric linear fitting, were < 0.01 Hz/cm, 0.18 Hz/cm, and 0.26 Hz/cm, respectively. These compared favorably with previous reports. We found that simulation voxel sizes greater than 5 mm can produce unreliable results. Conclusion: We have presented an efficient simulation framework for respiration-induced $B_0$ variation in the head. The method can be used to predict $B_0$ shifts with high spatiotemporal resolution under different breathing conditions and aid in the design of dynamic $B_0$ compensation strategies.

• Journal of Ginseng Research
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• v.12 no.1
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• pp.11-29
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• 1988

This study was conducted to investigate the effect of light intensity and temperature on the photosynthesis and respiration of ginseng plant. Highly significant, second degree curvilinear regressions were recognized among the photosynthesis of ginseng leaves, light intensity and temperature. And an interaction between the effects of light intensity and temperature on the photosynthesis of ginseng leaves was found to be highly significant. The increasing rate of photosynthesis with the increase of light intensity was markedly decreased with increasing temperature. The light compensation point of ginseng leaves was significantly varied with temperature, and the average point was approximately 600 lux. The light saturation point of Korean ginseng was 11,000 lux at $15^{\circ}C$ and $20^{\circ}C$ and around 9,500 lux at above $25^{\circ}C$. The decreasing rate of photosynthesis with the increase of temperature significantly increased with increasing light intensity. The optimum temperature for the photosynthesis of ginseng leaves was about 15 to $22^{\circ}C$ and markedly decreased with increasing light intensity. The highest photosynthesis occurred in ginseng leaves grown with the shade of 15% transmittance. The respiration of ginseng leaves increased with the shade of 5% and/or 30% transmittance. High temperature stimulated the respiration of ginseng leaves. Percent respiration to photosynthesis of ginseng leaves grown with the shade was increased at high temperature and decreased with increasing light Intensity. It was also increased with increasing transmittance. The maximum $CO_2$ absorption of ginseng leaves grown with the shade of 5Ps and ISVS transmittance accurred at 9 o'clock a.m., whereas that of 20% transmittance occurred at 7-9 o'clock a.m. The duration of $CO_2$ absorption was distinctively long with the shade of high transmittance. The $CO_2$ compensation point in the photosynthesis of ginseng leaves was 130 ppm.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.4
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• pp.97-104
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• 2010

In this paper, we provide an embedded type non-contact bio-radar heart and respiration rate monitoring system. We implemented the rate finding algorithm into the embedded system. The high-speed and reliable real-time signal processor is then tested. To avoid null-point data loss problem, we applied quadrature demodulation. Among several other combining techniques, we suggest arctangent demodulation for quadrature channel combining and DSP is used for real-time signal processing. We also suggest DC-offset compensation technique to preserve the wanted DC components of the IQ signals for accurate demodulation while keeping the dynamic range of the ADC lower. Using Texas Instrument C6711 series DSP and external 12Bit ADC, we implemented proper elliptic digital filter and autocorrelation detection algorithm for robust commercial hand held device.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.320-330
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• 2012

This study was conducted to investigate the changes of chlorophyll contents, chlorophyll fluorescence, photosynthetic parameters, and leaf growth of Synurus deltoides under different shading treatments. S. deltoides was grown under non-treated (full sunlight) and three different shading conditions (Shaded 88~93%, 65~75%, and 45%~55%). Light compensation point ($L_{comp}$), dark respiration ($D_{resp}$), maximum photosynthesis rate ($Pn_{max}$), photo respiration rate ($P_{resp}$), carboxylation efficiency ($\Phi_{carb}$), and photochemical efficiency were decreased with increasing shading level; However, $CO_2$ compensation point ($CO_{2\;comp}$), total chlorophyll content, and specific leaf area (SLA) were shown the opposite trend. S. deltoides under 88~93% treatment showed the lowest photosynthetic activity such as maximum photosynthetic rate ($Pn_{max}$), photochemical efficiency, and $CO_2$ compensation point ($CO_{2\;comp}$). Therefore, photosynthetic activity will be sharply decreased with a long period of 8~12% of full sunlight. With the shading level decreased, carotenoid content and non-photochemical fluorescence quenching (NPQ) increased to prevent excessive light damage. This result suggested that growth and physiology of S. deltoides adapted to high light intensity through regulating its internal mechanism.

• Investigative Magnetic Resonance Imaging
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• v.22 no.4
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• pp.209-217
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• 2018

Purpose: The objective of this study was to obtain improved susceptibility weighted images (SWI) of the cervical spinal cord using respiratory-induced artifact compensation. Materials and Methods: The artifact from $B_0$ fluctuations by respiration could be compensated using a double navigator echo approach. The two navigators were inserted in an SWI sequence before and after the image readouts. The $B_0$ fluctuation was measured by each navigator echoes, and the inverse of the fluctuation was applied to eliminate the artifact from fluctuation. The degree of compensation was quantified using a quality index (QI) term for compensated imaging using each navigator. Also, the effect of compensation was analyzed according to the position of the spinal cord using QI values. Results: Compensation using navigator echo gave the improved visualization of SWI in cervical spinal cord compared to non-compensated images. Before compensation, images were influenced by artificial noise from motion in both the superior (QI = 0.031) and inferior (QI = 0.043) regions. In most parts of the superior regions, the second navigator resulted in better quality (QI = 0.024, P < 0.01) compared to the first navigator, but in the inferior regions the first navigator showed better quality (QI = 0.033, P < 0.01) after correction. Conclusion: Motion compensation using a double navigator method can increase the improvement of the SWI in the cervical spinal cord. The proposed method makes SWI a useful tool for the diagnosis of spinal cord injury by reducing respiratory-induced artifact.

• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.195-199
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• 1995

This study was conducted to investigate the Net photosynthesis and respiration rates among the varieties of Soybean(Eunha, Pangsa and Paldal that have high yields) at various leaf temperature and light intensity at the stage of $V_5$. The relations between the Net photosynthesis rate and SLW(specific leaf weight) and chlorophyll content were also investigated. 1. Net photosynthesis rates at $25^{\circ}C$ were $21.5mgdm^{-2}h^{-1}$ in cv. Eunha, $20.2mgdm^{-2}h^{-1}$ in cv. Pangsa and $18.5mgdm^{-2}h^{-1}$ in cv. Paldal. 2. Most cultivars of Soybean showed the maximum rates of Net photosynthesis at $25^{\circ}C$, especially in cv. Eunha. Also Net photosynthesis rates differed depending on the leaf shape. Long leaf shape(cv. Eunha) was better than round leaf shape(cv. Paldal) in Net photosynthesis rate. 3. Respiration rates of leaves in Eunha, Pangse and Paldal were $0.56mgdm^{-2}h^{-1}$ at $15^{\circ}C$, $0.79mgdm^{-2}h^{-1}$ at $20^{\circ}C$ $1.15mgdm^{-2}h^{-1}$ at $25^{\circ}C$ and $1.37mgdm^{-2}h^{-1}$ at $30^{\circ}C$. 4. Specific leaf weight were $3.1mg/cm^2$ in Pangsa, $3.5mg/cm^2$ in Eunha and Paldal. No signlficant difference were showed in net photosynthesis rates and specific lear weight. 5. Leaf chlorophyll content were $2.48{\mu}g/gF.W.$ in Eunha, $2.19{\mu}g/gF.W.$ in Pangsa and $1.67{\mu}/g F.W.$ in Paldal. Significant difference were showed in Net photosynthesis rates and Leaf chlorophyll content. 6. The estimated compensation points at which net photosynthesis approached zero were $10{\mu}Em^{-2}s^{-1}$ in Eunha, Pangsa, and Palda at 1$5^{\circ}C$. The compensation point in cv. Eunha at $20^{\circ}C$ was $12P{\mu}Em^{-2}s{-1}$ while $13{\mu}Em^{-2}s{-1}$ in Pangsa and Palda. The compensation point in cv. Paldal at $25^{\circ}C$ was $18{\mu}Em^{-2}s{-1}$ while $16{\mu}Em^{-2}s{-1}$ in Eunha and Pangsa. The compensation point in cv. Palda at $30^{\circ}C$ was $23{\mu}Em^{-2}s{-1}$ Palda while $13{\mu}Em^{-2}s{-1}$ in Eunha and Pangsa.