• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.7 no.2
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• pp.80-86
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• 1978

The distribution of temperature obtained by the solution of Schumann equation and that of experimentally obtained on tile cooling process of packed bed of citrus unshu show a good agreement, and the maximum deviation is only $1-2^{\circ}C$. The agreement means that it is possible to apply the Schumann model to the cooling process of packed bed of citrus unshu. In considering respiration heat, the numberical result by the solution of the equation is that in case of the velocity of gas $(3^{\circ}C)$ is above 1m/sec, becomes below 0.01 and effect of respiration heat is negligible and in case of below 1m/sec the velocity of gas $(3^{\circ}C)$ is above 0.01 and the effect of respiration heat must be consideied. We Present the Practically easily applicable figure of cooling characteristic line on the both . cases of short term cooling Process and long time storage of citrus unshu.

• Journal of Environmental Impact Assessment
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• v.19 no.6
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• pp.617-623
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• 2010

It is the most important subject to figure out characteristics of the wastewater inflows of sewerage treatment plant(STP) when situation models are applied to operation of the biological processes and in the automatic control based on ICA(Instrument, Control and Automation). For the purposes, real-time influent monitoring method has been applied by using on-line monitoring equipments for the process optimization in conventional STP. Since, the influent of STP is consist of complex components such as, COD, BOD, TN, $NH_4$-N, $NO_3$-N, TP and $PO_4$-P. MRA2(Microbial Respiration Analyzer 2), which is capable of real-time analyzing of wastewater characteristics is used to overcome the limitations and defects of conventional online monitoring equipments in this study. Rapidity, accuracy and stability of developed MRA2 are evaluated and compared with the results from on-line monitoring equipments for seven months after installation in Full-scale STP.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.410-414
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• 2004

To understand the postharvest characteristics of soybean sprouts, 5-day-old sprouts were harvested, packed in PE film, and stored at 4, 12, and $20^{\circ}C$ for up to 4 days. In addition, the sprout respiration rate was measured after storage at 4, 8, 12, 16, 20, and $24^{\circ}C$ for up to 20h. During the first day of storage at $20^{\circ}C$, the sprouts maintained temperature-dependent longitudinal growth, especially of hypocotyl length; hypocotyl and root grew 0.8cm and 0.2cm, respectively. The hypocotyl thickness decreased by 11, 13, and $18\%$ after 4 days of storage at 4, 12, and $20^{\circ}C$, respectively. No temperature-dependent differences in fresh weight, dry weight, or water content were found, despite decreases of $3\%$ over the 4 days of storage. A significant postharvest decrease of $50\%$ in vitamin C content was observed in the sprouts stored at $20^{\circ}C$ for 3days. Based on the $CO_2$ production rate, the soybean sprouts exhibited an increase in respiration in proportion to the storage temperature; sprouts stored at 8, 12, 16, 20 and $24^{\circ}C$ showed approximately 2, 5, 6, 11, and 17 times, respectively, than the respiration rate of sprouts stored at $4^{\circ}C$. These results indicate the importance of low temperature storage during market circulation for minimizing the postharvest morphological and nutritional degradation of soybean sprouts.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.3
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• pp.491-498
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• 2022

In our daily life, quality of sleeping is closely related to happiness index. Whether or not people perceive sleep disturbance as a chronic disease, people complain of many difficulties, and in their daily life, they often experience difficulty breathing during sleep. It is very important to automatically recognize breathing-related disorders during a sleep, but it is very difficult in reality. To solve this problem, this paper proposes a mobile-based non-contact sleeping monitoring for health management at home. Respiratory signals during the sleep are collected by using the sound sensor of the smartphone, the characteristics of the signals are extracted, and the frequency, amplitude, respiration rate, and pattern of respiration are analyzed. Although mobile health does not solve all problems, it aims at early detection and continuous management of individual health conditions, and shows the possibility of monitoring physiological data such as respiration during the sleep without additional sensors with a smartphone in the bedroom of an ordinary home.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.3
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• pp.13-25
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• 2022

Purpose : The purpose of this study was to investigate the effects of combined cervical stabilization exercise (CSE) and stretching exercise (SE) on office workers with forward head posture (FHP). Methods : A total of 32 office workers with forward head posture were randomly assigned to experimental (n=16) and control (n=16) groups. The experimental group underwent combined CSE and SE, and the control group underwent cervical self-myofascial release and SE. Both groups performed exercises for 40 min per day, thrice per week for a total of 6 weeks. Craniovertebral angle (CVA), respiration, disability, and joint range of motion (ROM) before and 6 weeks after intervention were measured and compared. Results : There was no significant between-group difference in the general characteristics (p>.05). The intra-group comparison showed significant differences in the visual analog scale (VAS) and neck disability index (NDI) of both groups post-intervention (p<.05). CVA and forced expiratory volume in 1 seconds (FEV₁) were significantly improved post-intervention in the experimental group only (p<.05). In the experimental group, all ROM variables were significantly improved post-intervention. In contrast, in the control group, all ROM variables improved significantly post-intervention, except for extension (p<.05). The inter-group comparison showed significant differences in NDI, left lateral flexion, right lateral flexion, and left rotation between the two groups (p<.05). Conclusion : The combination of CSE and SE, which stabilizes the cervical spine, had positive effects on cranial rotation angle, respiration, disability, and joint ROM in office workers with forward head posture. Therefore, the combination of the two exercises may be an effective option to reduce symptoms and prevent postural problems in office workers with FHP.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.3
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• pp.433-444
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• 2020

This study proposes a method to improve the sleep stage and efficiency estimation of sleep apnea patients using a UWB (Ultra-Wideband) radar. Motion and respiration extracted from the radar signal were used. Respiratory signal disturbances by motion artifacts and irregular respiration patterns of sleep apnea patients are compensated for in the preprocessing stage. Preprocessing calculates the standard deviation of the respiration signal for a shift window of 15 seconds to estimate thresholds for compensation and applies it to the breathing signal. The method for estimating the sleep stage is based on the difference in amplitude of two kinds of smoothed respirations signals. In smoothing, the window size is set to 10 seconds and 34 seconds, respectively. The estimated feature was processed by the k-nearest neighbor classifier and the feature filtering model to discriminate between the sleep periods of the rapid eye movement (REM) and non-rapid eye movement (NREM). The feature filtering model reflects the characteristics of the REM sleep that occur continuously and the characteristics that mainly occur in the latter part of this stage. The sleep efficiency is estimated by using the sleep onset time and motion events. Sleep onset time uses estimated features from the gradient changes of the breathing signal. A motion event was applied based on the estimated energy change in the UWB signal. Sleep efficiency and sleep stage accuracy were assessed with polysomnography. The average sleep efficiency and sleep stage accuracy were estimated respectively to be about 96.3% and 88.8% in 18 sleep apnea subjects.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.737-754
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• 2019

Peaches have soft tissues compared to other fruits and are vulnerable to softness, wounds, and loss of marketability due to the weak fruit hardness after harvest. It is necessary to develop a technology to improve the shelf-life of the fruit to expand the distribution of peaches. Calcium compounds and chitosan have an important role in improving the shelf-life of fruit by maintaining the hardness and reducing the respiration rate in peach fruits. In this study, to select useful compounds to improve the shelf-life of peaches, calcium citrate, calcium chloride, calcium nitrate, GH-Ca, OS-Ca, chitosan, and chitosan dissolved in calcium chloride were sprayed onto peach trees. The characteristics of the harvested fruits were investigated after the 'Kumhong' and 'Madoka' peach tree treatments. The hardness of the fruit was kept the highest with the combined treatment and remained high with the calcium citrate, chitosan and calcium nitrate treatments. Ethylene production and respiration were effectively inhibited by the GH-Ca and chitosan treatments. There was no significant difference in soluble solids content and acidity among the fruits treated with the chemicals. The coloration of the fruit skin was not delayed by the calcium and chitosan chemical treatments. Calcium compounds were increased in the fruits and leaves of the peach trees treated with the chemicals compared to the untreated ones. These results suggest that the calcium treatment extended the shelf-life by increasing the calcium content in the leaves and fruits of the peach trees.

• The Journal of Korean Medicine
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• v.37 no.2
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• pp.36-44
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• 2016

Objectives: This study aimed to evaluate the effects of breath-counting meditation (BCM) and deep breathing (DB) on heart rate variability (HRV). These breathing techniques have the characteristics of non-paced and self-controlled breathings, resulting in less increase of HRV. We also compared BCM and DB with usual breathing (UB) or relaxing breathing (RB) which can reveal the characteristics of those. Methods: 83 healthy volunteers sitting in chairs performed non-paced breathing; UB, RB, BCM, and DB each for 5 minutes. One minute of relaxation was permitted between breathings. Participants surfed the internet sitting in front of a computer during UB, while for RB, they remained steady with eyes closed. For BCM, they breathed inwardly counting from 1 to 10 repetitively, while they took a deep breath during DB. Physiological indices were simultaneously recorded with a biofeedback system. Results: Respiration rate, thoracic amplitude, and mean heart rate decreased in RB compared with UB, but there was no change in HRV. Respiration rate in BCM and DB was lower than that in UB or RB, and the amplitude of thorax or abdomen, and HRV all increased (p<0.05). However, mean heart rate and skin conductance decreased in BCM compared with UB (p<0.05), whereas those were no different between DB and UB. Conclusion: BCM, just concentrating mentally on breathing with counting each breath, can increase HRV with less sympathetic activation, while DB, actively moving thorax and abdomen for achieving the deepest respiration rate, can greatly raise HRV with the maintenance of mean vagal or sympathetic tone.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.92-99
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• 1988

The dark respiration, photosynthesis($CO_2$ refixation), $CO_2$ balance and chlorophyll content of 1st-year conelets and 2nd-year cones of Korean pine(Pinus koraiensis S.et.Z.) were investigated after pollination up to the end of maturation. The results obtained are as follows : 1. The growth of 1st-year conelet was 3.6cm in length. 2.4cm in diameter and 3.058 in dry weighs during the first year. The growth of 2nd-year mature cone was 13.5cm in length, 9.3cm in diameter and 141.0g in dry weight in the late of 2nd-year. 2. The refixation of carbon dioxide released from a cone by the dark respiration was less than 50 percent at light saturation through the growing period. The refixation of carbon dioxide released by dark respiration for one year was 7.3 percent in 1st-year conelets and 8.7 percent in 2nd-year cones. 3. The dark respiration rate of cones by increasing temperature was rapidly increased with increasing temperature up to $25^{\circ}C$. The dark respiration rate of cones was much higher in non-growing season than that in growing season at the same temperature. 4. The rates of dark respiration and $CO_2$ refixation, based on the dry weight, were much higher in 1st-year conelet than that in 2nd-year cone. 5. The $CO_2$ balance for a cone was negative from pollination to the end of maturation. The net dark respiration loss for a cone was 7.23g $CO_2$/year in 1st-year conelet and 164.8g $CO_2$/year in 2nd-year cone. 6. The respiratory loss efficiency for a cone(=$CH_2O$ weight calculated by net dark respiration/dry weight of cone) for one year was 1.61 in 1st-year conelet and 0.81 in 2nd-year cone for one year. 7. The total chlorophyll content of surface scale of the cone was lower than 2mg/g dw through the growing period, and chl. a/b ratio was 2 to 3.

• Food Science and Preservation
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• v.5 no.2
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• pp.119-122
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• 1998

This study was conducted to blow the effect of postharvest physiological changes on garlic quality according to its ecotypes and storage temperatures. The changes of water, total soluble solids, crude stein, md total fructans were measured and the rates of respiration and sprouting were analyzed during storage at 20$^{\circ}C$ and 30$^{\circ}C$. The decrease of water content and the increase of total soluble solids were reversely appeared during garlic storage. The crude protein content was gradually increased during storage but total fructan content was decrased. The respiration late was maximized at 60days after storage and the spouting rate was gradually increased. In the aspect of ecotypic characteristics, the water content, fructan content and sprouting rate were higher in 'Namdo' cultivar than those of southern type. The high storage temperature (30$^{\circ}C$) controlled spouting and loss of fructan, and it was effective to maintain the garlic quality.