• The Journal of Korean Medicine
• /
• v.39 no.1
• /
• pp.44-54
• /
• 2018

Objectives: The objective of this study is to investigate the effects of drinking alcohol on bio-electrical potential at twelve source points. Methods: Twenty healthy adults were assigned to alcohol and water groups by a random cross-over design. Bio-electrical potential at twelve source points were measured before and after drinking alcohol or water and the change of bio-electrical potential was analyzed and compared between the alcohol and the water groups. Results: Bio-electrical potential at LI4, ST42, KI3, PC7, TE4, GB40, LR3 in the alcohol group was significantly increased compared to those in the water group. Conclusions: Drinking alcohol increased bio-electrical potential at source points of LI, ST, KI, PC, TE, GB and LR in healthy human subjects.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.75-81
• /
• 2008

The water shortage in mega cities in Asia, which face a rapid growth in urban population, is an outstanding problem. It is important, therefore, to accurately estimate the water balance in each city in order to use the limited water resources effectively. In this study, we estimated the potential water resources in し sixteen mega cities in Asia. The target cities were Delhi and Calcutta, India; Colombo, Sri Lanka; Dhaka, Bangladesh; Yangon, Myanmar; Bangkok, Thailand; Kuala Lumpur, Malaysia; Singapore; Jakarta, Indonesia; Hanoi, Vietnam; Beijing and Hong Kong, the People's Republic of China; Seoul, the People's Republic of Korea; Manila, the Philippines, and Sapporo and Tokyo, Japan. The potential water resources were estimated by subtracting the actual evaporation from the amount of rainfall. The actual evaporation was estimated using the potential evaporation obtained by Hamon's equation which requires the air temperature and the possible hours of sunshine. When the results of Hamon's and Penman's evaporation equations were compared, a considerable error appeared in the low latitude region. The estimation using Hamon's equation was corrected with the linear regression line of Hamon's and Penman's equations. A classification of the land cover was carried out based on satellite photographs of the target cities, and the volume of surface runoff for each city was obtained using the runoff ratios which depended on the land cover. As a result, the potential water resources in the above mega cities in Asia were found to be greater than the world average. However, the actual water resources which are available for one person to use are probably very limited.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.61 no.2
• /
• pp.97-104
• /
• 2019

The purpose of this study was to establish the estimation method of irrigation water amount for sewage treated water reuse for agricultural purpose. To calculate the irrigation water amount, we adopted Penman-Monteith for potential evapotranspiration estimation and applied crop coefficient and irrigation efficiency factor. We developed the irrigation water amount calculation program using C language in Xcode environment. The target district for calculation is having 259 ha of agricultural land located near the Jinyeong Clear Water Circulation Center in Hanrim-myeon, Gimhae city. The meteorological data of the study area were obtained from Changwon weather station from 1986 to 2017. Calculated average and maximum of annual mean potential evapotranspiration were 2.72 mm/day and 6.22 mm/day, respectively. We used K-S (Kolmogorov-Smirnov) for goodness-of-fit test to find optimal probability distribution of annual mean and maximum evapotranspiration. As a result, the normal distribution was selected for the appropriate distribution. The annual mean and maximum potential evapotranspiration for 10-year return period by applying normal distribution were 2.88 mm/day and 6.76 mm/day, respectively. Assuming that the irrigation efficiency is 80%, the irrigation water requirement was calculated as $36.05m^3/day/ha$ and $84.45m^3/day/ha$, respectively, when annual mean and maximum potential evapotranspiration were applied. The actual irrigation water amount can be calculated by applying the crop coefficient and cropping days for the study area based on the developed irrigation water amount estimation program in this study.

• Journal of Korean Society of Forest Science
• /
• v.63 no.1
• /
• pp.28-34
• /
• 1984

This study was to elucidate the relation between the water relations parameters obtained from P-V curves and stomatal closure. The results obtained are as follows: 1) The water potential at incipient plasmolysis obtained from P-V curves was similar to the water potential at critical stomatal closure. 2) The critical stomatal closure of sun leaves appear at -21 bar (-17 bar, shade leaves) in Pinus koraiensis, -20 bar in Pinus rigida, -22 bar in Pinus densiflora, and -24 bar in Larix leptolepis. On a relative water content basis, the critical stomatal closures of sun leaves appear at 85% (82%, shade leaves) in Pinus kordiensis, 77% in Pinus ragida, 85% in Pinus densiflora, and 70% in Larix leptolepis. 3) The incipient stomatal closures of sun leaves appear at -14 bar (-12 bar, shade leaves) in Pinus koraiensis, -10 bar in Pinus rigida, -15 bar in Pinus densiflora, and -6 bar in Larix leptolepis. On a relative water content basis, the incipient stomatal closures of sun leaves appear at 90% in Pinus koraiensis, 93% in Pinus rigida, 90% in Pinus densiflora, and 93% in Larix leptolepis. 4) The leaf conductance was increased by increase in volume-averaged turgor pressure was linearly increased by increase in relative water content.

• Journal of Korean Society on Water Environment
• /
• v.26 no.1
• /
• pp.133-139
• /
• 2010

Global human activities associated with the use of fossil fuels have aggravated climate change, increasing air temperature. Consequently, climate change has the potential to alter surface water temperature with significant impacts on biogeochemical cycling and ecosystems in natural water body. In this study, we examined temporal trends on historical records of surface water temperature, and investigated the air temperature/water temperature relationship and the potential water temperature change from an air temperature scenario developed with regional climate model. Although the temporal trends of water temperature are highly variable site-by-site, surface water temperature was highly dependent on air temperature, and has increased significantly in some sub-watersheds over the last two decades. The results presented here demonstrate that water temperature changes are expected to be slightly higher in river system than reservoir systems and more significant during winter than summer for both river and reservoir system. Projected change of surface water temperature will likely increase $1.06^{\circ}C$ for rivers and $0.95^{\circ}C$ for reservoirs during the period 2008 to 2050. Given the potential climatic changes, every $1^{\circ}C$ increase in water temperature could cause dissolved oxygen levels to fall every 0.206 ppm.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.3
• /
• pp.223-231
• /
• 1994

To investigate effects of water stress on leaf water potential, nitrate reductase activity and abscisic acid content, Paldalkong, Saealkong and Danyeobkong were subjected to water stress by polyethyene glycol(PEG, MW=6,000) in the water culture and withholding irrigation in soil culture. Leaf water potential and nitrate reductase activity decreased with increaseing of PEG concentration in the water culture. These were higher at 3rd and 5th leaf stage than at 1st leaf stage. Leaf water potential showed no significant differance among the varieties, but nitrate redutase activity was higher in Paldalkong than in Saealkong and Danyeobkong. Leaf water potential and nitrate reductase activity decreased approximately 2.2 times (-1.67 MPa/-0.75MPa) and 47%(3.1${\mu}$ mole nitrite/g.DW/hour/15.9${\mu}$ mole nitrite/g.DW/hour) to control, respectively, after 3 days from water stress treatment in the soil culture. According to increasing PEG concentration, abscisic acid content increased in the water culture and was higher at 5th leaf stage than at 1st and 3rd leaf stage. Paldalkong showed the highest abscisic acid content. Abscisic acid content increased approximately 1.7 times (9.9nmole/g.DW/5.7nmole/g.DW) compared to the control after 3 days from water stress treatment in the soil culture.

• The Korean Journal of Ecology
• /
• v.16 no.3
• /
• pp.353-364
• /
• 1993

To elucidate ecophysiological factors affecting nutural distribution of evergreen broad-leabed trees in Danohad National Marine Park, water potential, relative water content and photosynthetic activities of 4 species, Cammellia japonica, Machilus thunbergii, Castanopsis cuspidata var.sieboldii and Quercus acuta, were potential began to decrease from 07:00h to its minimum value at 13:00h for C. cuspidata var. sieboldii (-14.3bar) and Q. acuta (-19.4bar) at 16:00 h for M. thunbergii(-17.0bar) and at 19:00 h for C. japonica (-14.5bar), and these showed similar trends to relative water content. Photosynthetic activities of 4 species began to increase from 7:00 h and reached maximum values before their minimum values of water potential occureed. Optimum temperature renges of photosynthetic activities was $18~20^{\circ}C$ for C. japonica - M. thunbergii and $14~16^{\circ}C$ for C. cuspidata var. sieboldii Quercus acuta.Q.acuta had the highest light saturation point of $0.4mM/m^2/s$ and C. japonica the lowest of $0.15mM/m^2/s$. Water potential of 4 species subjected to water stress, began to decrease after 1st day of drought and after 21th day of drought, those of C. japonica, M. thunbergii, C. cuspidata var. sieboldii and Q. acuta decreased to species began to decrease after 7th day of drought and after 21th day, those of M. thunbergii, C. cuspidata var. sieboldii and Q. acuta were dropped to about 50% and C. japonica 83.5%. Photosynthetic activity of 4 specie began to decline in the order of C. cuspidata var. sieboldii, Q.acuta, C. japonica and M. thunbergii after 10th day of drought. These results suggest that the segregated disributions of C. japonica - M. thunbergii on vally positions and C. cuspidata var. sieboldii - Q. acuta on slopes were associated with different responses of water status and photosyntheties to their environment.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.58 no.2
• /
• pp.65-71
• /
• 2016

The new concept of agricultural water supply potential, which is mean annual turnover rate times unit storage capacity, was introduced for agricultural reservoirs. We investigated characteristics of mean annual turnover rate and unit storage capacity for agricultural reservoirs with storage capacity of over $1million\;m^3$. The curve of agricultural water supply potential represents change in mean annul turnover rate according to change in unit storage capacity. The mean annual turnover rate and unit storage capacity in the reservoirs with high minimum storage ratio are significantly higher than those in the reservoirs with low minimum storage ratio. Most of unstable water supply reservoirs showed low mean annual turnover rate or low unit storage capacity, indicating that mean annual turnover rate may be an index of stability degree for agricultural water use. The reservoirs with mean annual turnover rate of over 2 and unit storage capacity of over 0.8 m may be estimated as the stable water supply zone for 10 frequency dry year. The reservoirs with high agricultural water supply potential can belong to the wide range of stable water supply zone. The results suggest that relation between mean annual turnover rate and unit storage capacity may be used in evaluating stability degree for agricultural water supply in the reservoirs.

• The Journal of Korean Physical Therapy
• /
• v.15 no.4
• /
• pp.455-465
• /
• 2003

The purpose of this study was to describe the alteration of muscle action potential of spastic upper extremity in a patient with cerebral palsy by the water temperature. We used seven patients with cerebral palsy. Participants classified according to each group in $29^{\circ}C,\;35^{\circ}C$ by the water temperature. All subjects participated 2 session, which at least 1 week between session. The test was measured continuously pre test, post-test by thermometer and surface EMG. The following results were obtained; 1. In changes of surface temperature, wrist flexor and extensor were significantly decreased in $29^{\circ}C$ (p<0.001) group but were significantly increased $35^{\circ}C$ group(p<0.01). 2. In changes of surface temperature, wrist flexor and extensor were significantly differenced between $29^{\circ}C$ and $35^{\circ}C$ group(p<0.001). 3. In changes of muscle action potential, wrist extension antagonist were significantly increased in $29^{\circ}C$ group(p<0.05). 4. In changes of muscle action potential, wrist flexion agonist were more significantly increased in $29^{\circ}C$ group(p<0.01). 5. In changes of muscle action potential, wrist extension antagonist were significantly differenced between $29^{\circ}C$ and $35^{\circ}C$ group(p<0.05). These results lead us to the conclusion that changes of muscle action potential of spastic upper extremity in a patient with cerebral palsy were influenced by the water temperature. Therefore, a further direction of this study will be to provide more evidence that a moderate water temperature have an effect on muscle tone in a patient with cerebral palsy.

• Journal of Bio-Environment Control
• /
• v.10 no.1
• /
• pp.1-9
• /
• 2001

Fruit growth in kiwifruit shows double sigmoid curve, but it does not certainly indicate as years. Therefore, I though the reason to be easy to the effect of water state change in kiwifruit, investigated diurnal change in water status of fruit tissues with an isoipiestic psychrometers against the fruit growth stage of kiwifruit in 1995 and 1996. Diurnal change in the fruit tissue water potential were little, but violent for fruti growth state III in 1996. The potential of two years dropped gradually approach to harvest time. On the other hand, osmotic potential of the tissues indicated to very similar to water potential, dropped rapidly -1.5MPa before dawn, recovered -1 MPa after 3 h on October 14, were -1~-1.7 MPa at the fruit commercial harvest in 1995. It had a tendency to lower in 1996 than in 1995. It was recorded to the minimum air temperature at the first for an autumn in 1995; 13$^{\circ}C$ from the middle night of October 13 to dawn of October 14. Leaves water potential, which is related to water status of xylem, nearly fell below -1 MPa at before dawn from stage II in 1996. However, it fell so low only at commercial in 1995. At the stage II, osmotic potential and ascent of the turgor pressure was high than 1995-fruit. There parameter suggested that three of kiwifruit in 1996 were status of water stress for stage III. The results from this study indicated that difference of fruit growth between 1995-fruit and 1996-fruit was affected by water status of the fruit tissues, which was influenced by weather condition.