• Journal of Ecology and Environment
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• v.35 no.4
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• pp.307-311
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• 2012

This study was conducted to evaluate the dynamics of soil respiration (total soil and heterotrophic respiration) following fertilizer application in red pine forests. Fertilizer (N:P:K = 113:150:37 kg/ha), which reflects current practices in Korean forest, was applied in April 2011, and total soil and heterotrophic respiration rates were monitored from April 2011 to March 2012. Monthly variation of total soil and heterotrophic respiration rates were similar between the fertilizer and control treatments, as soil temperature was the dominant factor controlling the both rates. Total soil respiration rates during the study period were not significantly different between the fertilizer (0.504 g $CO_2\;m^{-2}\;h^{-1}$) and control (0.501 g $CO_2\;m^{-2}\;h^{-1}$) treatments. However, the proportion of heterotrophic respiration was higher in the fertilizer (78% of total soil respiration rates) than in the control (62% of total soil respiration rates) treatments. These results suggest that current fertilizer practices in Korea forest soil do not substantially affect total soil respiration rates.

• Journal of Ecology and Environment
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• v.29 no.5
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• pp.433-438
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• 2006

To elucidate the mechanisms by which algal food quality affect Daphnia growths, we measured carbon incorporation rates and respiration rates of Daphnia magna with Cryptomonad Rhodomonas minuta, green algae Scenedesmus acutus and cyanobacteria Synechococcus sp. with varying physiological states as food. Carbon assimilation rates were high with R. minuta and S. acutus and low with Synechococcus sp. showing a similar pattern to the growth rate pattern. There was no clear difference among respiration rates of three algal species. Carbon assimilation rates and respiration rates of D. magna appeared to be independent on Molar C:P ratios in algal foods. Carbon growth efficiencies (incorporated carbon per assimilated carbon amount) were lower when D. magna fed with Synechococcus sp. than fed with R. minuta or S. acutus. Analysis of variance results show that carbon assimilation rates which were sum of incorporation and respiration rates and carbon growth efficiencies were only dependant on species affiliation. Overall, our results showed that algal species with varying ${\omega}3$ polyunsaturated fatty acid content led different carbon incorporation rates and overall carbon assimilation rates of D. magna.

• Applied Microscopy
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• v.19 no.2
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• pp.43-58
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• 1989

To investigate the effects of hexavalent chromium on mitochondrial respiration of rat kidney, various hexavalent chromium concentrations were treated, then respiration and electron transfer enzyme activities were measured. Ultrastructural changes at state IV respiration of mitochondria were also observed. Then, to investigate protective role against hexavalent chromium in the body, low-molecular-weight, chromium-binding substances (LMCr) were purified from livers of rabbits 2hr after intravenously administrated with sodium dichromate at a dose of 74mg per kg body weight. And then, respiration rates of mitochondria treated with LMCr, hexavalent chromium containing 0.7mM chromium were measured. Hexavalent chromium decreased state IV respiration rates and electron transfer enzyme activities of mitochondria, and increased labile membrane and swelling. And partial inhibitions of condensed to orthodox conformational change were observed. Respiration rates of mitochondria treated with LMCr containing 0.7mM chromium did not differ from that of the non-treated mitochondria. But respiration rates of 0.7mM hexavalent chromium-treated mitochondria decreased by 42%, compared to non-treated mitochondria. These results suggest that LMCr may play an important role in detoxification of toxic hexavalent chromium.

• The Korean Journal of Ecology
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• v.24 no.2
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• pp.87-91
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• 2001

The response of respiration rates of root, Ao layer and mineral soil to varying environmental factors was studied in Popuius maximowiczii stand (25-year-old) during the growing season of 1997. Soil temperature showed a pronounced seasonal course, in contrast to soil moisture. The mineral soil respiration was high in August, and root and Ao layer respiration, were high in July. An exponential equation best described the relationships between soil temperature and mineral soil respiration, and total soil respiration (r＝0.95 and 0.92, p＜0.001), respectively. In P. maximowiczii stand, soil respiration rates were reduced by about 19% after removal of the Ao layer, and by about 30% after removal of living root. Therefore, mineral soil respiration seemed to contribute gretly to the total soil respiration (50%).

• Animal cells and systems
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• v.10 no.4
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• pp.191-196
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• 2006

This study was carried out to evaluate soil carbon cycling of a 36-year-old larch (Larix leptolepis) stand in Korea. The aboveground and soil organic carbon storage, litterfall, and soil respiration rates were measured over twoyear periods. The estimated aboveground biomass carbon storage and increment were 4220 gC $m^{-2}$ and 150 gC $m^{-2}\;yr^{-1}$, respectively. Mean organic carbon inputs by needle and total litterfall were 118 gC $m^{-2}\;yr^{-1}$ and 168 gC $m^{-2}\;yr^{-1}$, respectively. The aboveground carbon increment of the stand was similar to the annual input of carbon from total litterfall. The soil respiration rates correlated exponentially with the soil temperature at a depth of 20 cm ($R^2$ = 0.86). In addition, the exponential regression equation indicated a relatively strong positive relationship between the soil respiration rates and soil temperature, while there was no significant relationship between the soil respiration rates and the soil moisture content. The annual mean and total soil respiration rates were 0.40 g $CO_2\;m^{-2} h^{-1}$ and 3010 g $CO_2\;m^{-2}\;yr^{-1}$ over the two-year study period, respectively.

• Journal of Biosystems Engineering
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• v.33 no.5
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• pp.326-332
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• 2008

A respiration measurement system for vital signs was developed. Respiration signals were measured, processed, and analyzed. Four electrodes, attached on the surface of the skin, were used to monitor respiration signals by impedance pneumography. The measured signals were amplified, detrended, filtered, and transferred toan embedded module. The Kalman filter was used to remove motion artifact from the respiration signals. Experiments were conducted at stable condition and walking condition to evaluate the performance of the system. Respiration rates of five males and five females were measured and analyzed at each condition. The referenced respiration signal was determined by temperature of nose surroundings. The results showed that the respiration rates at the walking condition had more motion artifacts than the stable condition. The accuracies of the respiration measurement system with Kalman filter were found as 96% at the stable condition and 95% at the walking condition. The results showed that the Kalman filter was an effective tool to remove the motion artifact from the respiration signal.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.1
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• pp.58-63
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• 2010

In this paper, we proposed a wearable respiration measurement system with textile capacitive pressure sensor. Belt typed textile capacitive pressure sensor approach of respiration measurement, from which respiration signatures and rates can be derived in real-time for long-term monitoring, are presented. Belt typed textile capacitive pressure sensor has been developed for this measurement system. the distance change of two plates by the pressure of motion has been used for the respiration measurement in chest area. Respiration rates measured with the textile capacitive pressure sensor was compared with standard techniques on 8 human subjects. Accurate measurement of respiration rate with developed sensor system is shown. The data from the method comparison study is used to confirm theoretical estimates of change in capacitance by the distance change. The current version of respiratory rate detection system using textile capacitive pressure sensor can successfully measure respiration rate. It showed upper limit agreement of $3.7997{\times}10^{-7}$ RPM, and lower limit of agreement of $-3.8428{\times}10^{-7}$ RPM in Bland-Altman plot. From all subject, high correlation were shown(p<0.0001). The proposed measurement method could be used to monitor unconscious persons, avoiding the need to apply electrodes to the directly skin or other sensors in the correct position and to wire the subject to the monitor. Monitoring respiration using textile capacitive pressure sensor offers a promising possibility of convenient measurement of respiration rates. Especially, this technology offers a potentially inexpensive implementation that could extend applications to consumer home-healthcare and mobile-healthcare products. Further advances in the sensor design, system design and signal processing can increase the range and quality of the rate-finding, broadening the potential application areas of this technology.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.2071-2078
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• 2009

In this paper, we proposed a non-contact respiration measurement system with ultrasonic proximity sensor. Ultrasonic proximity sensor approach of respiration measurement which respiration signatures and rates can be derived in real-time for long-term monitoring is presented. 240 kHz ultrasonic sensor has been applied for the proposed measurement system. The time of flight of sound wave between the transmitted signal and received signal have been used for a respiration measurement from abdominal area. Respiration rates measured with the ultrasonic proximity sensor were compared with those measured with standard techniques on 5 human subjects. Accurate measurement of respiration rate is shown from the 50 cm measurement distance. The data from the method comparison study is used to confirm the performance of the proposed measurement system. The current version of respiratory rate detection system using ultrasonic can successfully measure respiration rate. The proposed measurement method could be used for monitoring unconscious persons from a relatively close range, avoiding the need to apply electrodes or other sensors in the correct position and to wire the subject to the monitor. Monitoring respiration using ultrasonic sensor offers a promising possibility of non-contact measurement of respiration rates. Especially, this technology offers a potentially inexpensive implementation that could extend applications to consumer home-healthcare and mobile-healthcare products. Further advances in the sensor design, system design and signal processing can increase the range of the measurement and quality of the rate-finding for broadening the potential application areas of this technology.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.2
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• pp.71-79
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• 2023

The quantification of soil respiration rates is important to understand carbon cycles of forest ecosystems. Soil respiration rates were assessed using Li-8100A soil flux system in one evergreen broadleaved (Quercus glauca Thunb.) and two coniferous (Cryptomeria japonica D. Don and Chamaecyparis obtusa Endl.) stands from May 2020 to April 2022 in southern Korea. Monthly variations of soil respiration rates were higher in the Q. glauca stand than in the C. japonica and the C. obtusa stands. The mean soil respiration rates were significantly higher in the Q. glauca stand (2.63µmol m^-2 s^-1) than in the C. japonica (0.93µmol m^-2 s^-1) and C. obtusa (0.99µmol m^-2 s^-1) stands. The three stands showed exponential relationships between soil respiration rates and soil temperature (R² = 0.44-0.80). The sensitivity of temperature (Q10 values) to soil respiration rates was highest in the Q. glauca stand (5.13), followed by the C. obtusa (3.10) and C. japonica (2.58) stands. These results indicate that soil respiration rates can be increased more in evergreen broadleaved stands than in coniferous stands under enhanced soil temperature.

• Food Science and Preservation
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• v.10 no.2
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• pp.142-146
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• 2003

In order to prepare allowable guidelines for weight loss for packed agricultural produces during distribution after harvest, resipration and transpiration rates were investigated for fruits such as peach, apple, pear, persimon and mandarin which produced in Korea. Respiration and transpiration rates were widely different from cultivar and harvesting season among same produces. Respiration rates were increased as an environmental temperature was increased. Moisture amount that produced by respiration in five fruits was 3.55∼107.67mg/kg/h and those moisture amounts were considered as no much influence for the strength of cartons for packing of fruits. Moisture amount produced from transpiration was 24 ∼ 1,195g for 15kg packing unit of fruits in 5 days. after harvest.