• Journal of Korean Society of Steel Construction
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• v.25 no.6
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• pp.613-622
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• 2013

Numerous water gates have been constructed and are under construction for the control of water level because, due to the topographical characteristics of mountainous area, many small size rivers are developed in Korean peninsula. Among the water gates, movable water gates are more efficient to control water level than the fixed water gates. By the field application of the movable water gates, many problems associated with the fixed water gates have been mitigated. The problems include the bottom water pollution, the change of habitats for the riparian organisms, etc. This is the reason to increase the field application of movable water gates. In the paper we present the result of analytical investigation pertaining to the structural behavior of multistage overturning movable water gate which is one of the movable water gates. In the analytical investigations, the finite element analysis on the constructed water gate has been conducted for illustration purposes and it was found that the multistage movable water gate is much better than the fixed and/or existing movable water gates in the point of structural and environmental performances.

• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.11-19
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• 2000

This study aims to examine the characteristics of the water quality variation in relation to the change of water exchange rate with respect to the development phases of the Pusan port. To clarify the characteristics, water exchange caused by the variations of coastline shape and water surface area was examined by the numerical experiments using the Lagrangian particle tracking model based on 2-D shallow water equation. As the results of numerical experiments, it was proved that the water exchange in the Pusan port was decreased mainly due to the port development and the breakwaters construction. During the port development phases from 1875 to 1998, 35% of the sea-space in the port had decreased to make hinterland spaces. This resulted in the loss of wet-land and coastline change as well as decrease of the water exchange rate at the sea side. The city population in that period had rapidly increased from several thousands to 4 millions, resulting in the large discharge of sewages into the port area. Under the these environmental conditions, it can be clearly said that the water quality in the Pusan port is sensitively affected by the discharge of urban sewages decrease of the water exchange rate in relation to port and urban developments. In the study, the temporal changes of water quality were discussed with respect to the port development phases. It was clear that the water quality wad controlled by the exchange rate change under the port development as well as the input impact into the port from the urbanized city area. To make clean sea of the Pusan port, it is suggested that the sewage control, the water exchange and coastline control should be systematically checked under the concept of eco-friendly development and environmental management.

• Journal of Environmental Science International
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• v.32 no.10
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• pp.675-684
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• 2023

In this study, the water supply reliability of the andong and Imha dam was analyzed using inflow data for 360 months from 1993 to 2022 through allocation model. First, in the analysis results of additional water supply to Deagu city, the water supply reliability of Rule (B) was the highest at 86% for andong dam, 84% for imha dam, and 80% for the control point. However, when the planned supply was supplied, the analysis results showed 94%, 93%, and 90%. Next, in the quantitative reliability analysis results, when considering additional water supply to Deagu city, Rule (A), Rule (B), and Rule (C) were analyzed as 88%, 88%, and 88%, respectively, based on the control point. When supplying the planned water supply, the quantitative reliability analysis results were 95% equally based on Rule (A), Rule (B), and Rule (C). Because of evaluating the two reliability methods, the number of shortages increases significantly when additional water is supplied to Daegu City, but the shortage is generally 5-7%, resulting in a relatively small shortage compared with the increase in the number of shortages. In the case of resilience and vulnerability, additional water supply to Daegu City takes more than two months to restore than the existing planned water supply, and the average shortage was calculated to be smaller than that of supplying the planned water. According to the results of the analysis, Andong dam has an average water storage of 130x106 m² and Imha dam has 50x106 m². In this deficient water supply can be compensated by water from the Nakdong river.

• Journal of Animal Science and Technology
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• v.52 no.3
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• pp.213-220
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• 2010

This study was executed to investigate the effects of drinking deep sea water treated by reverse osmosis process (RO-DSW) on growth performance, nutrient utilizability, relative weight of lymphoid organs and the concentration of serum immunoglobulin G (IgG) in broiler chickens. A total of 200 one day old broiler chickens (Ross 308) were equally and randomly distributed into 10 ground floor pens (20 chicks per pen, 5 pens per treatment) bedded with rice-husks. The broilers were offered either fresh tap water (Control) or RO-DSW for 28 days (from d 6 to d 33) as the drinking water. The same basal phase 1 diet for first 2 weeks and phase 2 diet for last 2 weeks were offered ad libitum to the birds. The RO-DSW was prepared by diluting 1:20 ratio with deionized water before offering to chickens. The diet for control birds was supplemented with 0.21 % of food-grade salt to satisfy salt need of the birds. Broiler feeding study resulted that there were no differences in amount of water consumption, mortality and FCR between RO-DSW and control chickens. However, feed intake and body weight gain were increased (p<0.05) by RO-DSW drinking. There was no (p>0.05) difference in nutrients utilizability between RO-DSW and fresh water drinking. There were no (p>0.05) differences in the immune response between the control and treatment group. The serum IgG levels were 3.01 vs 2.87 mg/ml and the relative weights of spleen, thymus and bursa of Fabricius were 0.23, 0.18 and 0.20 vs. 0.20, 0.17 and 0.14 for RO-DSW vs. control birds, respectively. The immune responses were tended to be improved by RO-DSW drinking. This study showed an improvement in weight gain and feed intake that could be induced by RO-DSW drinking, although it is difficult to explain the reasons of the improvement at this moment. This study implied that RO-DSW could be successfully used as drinking water to broiler chickens.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.788-793
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• 2014

In this study, the electrical power consumption saving effect is studied through installing an inverter which is able to control the R.P.M. of marine sea water pump by effective flow control. The study looks at how sea water pump's flow control influences on the system without the Marine Growths Protection System(MGPS). Auxiliary sea water pump and refrigerator sea water pump in training ships, which are always operated not only in harbor but also in navigation, was used in the experiment and the experiment was conducted by dividing into harbor and navigation. As a result of research, in the case the sea water temperature is under $18^{\circ}C$, the operation was possible with a 58.3 % decrease in pump R.P.M. and electric power consumption was saved by 50 %. In spite of the sea water temperature increasing upto $34^{\circ}C$, pump R.P.M. at 91.6 % was sufficient to operate with a 20 % electric power consumption saving effect. In the pipelines without MGPS, lowering R.P.M. along with lowering pressure results in the attachment of various marine growths.

• Food Science and Preservation
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• v.17 no.1
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• pp.50-57
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• 2010

To develop a new functional kimchi with antioxidative properties, salted baechu was soaked in black rice water extract for 6 h at room temperature. The antioxidative property of the water extract was $78.75{\pm}1.18%$ that of the control (0.1% [w/v] alpha-tocopherol). The black rice gel was added to the baechu kimchi preparation. The color of baechu kimchi treated with black rice water extract changed to dark violet and/or black. Control kimchi and black rice water-treated kimchi were stored at $4^{\circ}C$ for 30 days. No significant differences were detected between the control and the black rice water-treated group in the early stages of fermentation. As fermentation time increased, pH decreased and titratable acidity increased rapidly in control kimchi. However, such marked changes were not evident in test kimchi. The hardness value of black rice water-treated kimchi was higher than that of control kimchi after the midpoint of the fermentation period. The storage life of baechu kimchi treated with black rice water extract was prolonged by up to 5 days compared with control samples, owing to a decline in lactic acid bacteria and yeast levels during the final fermentation period in black rice water-treated kimchi. The total phenolic levels and the antioxidative capacity of black rice water-treated kimchi (83%) were approximately 1.5-fold higher than in control kimchi (57%). In sensory evaluation, black rice water-treated kimchi scored higher than did control kimchi using a blind test protocol.

• 한국기계연구소 소보
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• s.16
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• pp.117-126
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• 1986

Trouble-free operation of cooling water systems is essential for efficient pro¬duction in most industrial facilities. Improper water treatments frequently cause such problems as corrosion, scaling, fouling and slime formation. Water quality, methods of cooling and materials of construction in the cooling circuit should be carefully studied before making selection of the water treatment programs. This paper reviewed cooling water problems encountered frequently in the open recirculating cooling systems and discussed the counter measures how to cope with them.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.255-277
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• 1998

The aim of this experiment was to investigate the effects of Aqua-Acupuncture of Yukmijiwangtang(六味地黃湯) and Palmijihwang-tang(八味地黃湯) water extracts applied at the meridian points BL 23(賢兪) and GV 4(命門) to test the renal function in normal rats. The results obtained were as follows; 1. Among the effects of Aqua-Acupuncture of Yukmijihwangtang water extract at the merdian point BL 23 group, there were significant changes in water balance and urine volume over a 1 week period; Both decreasing and decreasing trends were exihibited. Urinary excretion of sodium and free water clearance changed significantly over a 2 week period; Both decreasing and increasing trends were exihibited, Urinary excretion of potassium, chloride and creatinine, plasma renin activity, plasma levels of aldosterone and atrial natriuretic peptide showed no significant differences compared to the contral group. 2. Among the effects of Aqua-Acupuncture of Palmljihwangtang water extract at the merdian point BL 23 group, there were significant changes in water balance and free water clearance over a 2 week period; a decreasing trend. Urinary excretion of creatinine changed significantly over a 2 week period; an increasing trend. Urinary excretion of chloride changed significantly over 1 week period; an increasing trend. The plasma levels of atrial natriuretic peptide changed significantly over 1 and 2 week period; an increasing trend. Urine volume, urinary excretion of sodium and pottasium, plasma renin activity and plasma level of aldosterone showed no significant differences compared to the control group. 3. Among the effects of Aqua-Acupuncture of Yukmijihwangtang water extract at the meridian point GV 4 group, there was significant decrease in water balance over a 2 week period; there was significant decrease in urine volwne and urinary excretion of sodium and creatinine over a 1 week period, followed by an increasing trend after 2 weeks. Urinary excretion of free water clearance demonstrated significant changes over both 1 and 2 week period; both increasing and decreasing trends were exihibited. Urinary excretion of chloride and plasma levels of aldosterone increased significantly over 1 and 2 week period. Plasma levels of atrial natriuretic peptide also decreased significantly. Plasma renin activity showed no significant differences compared to the control group. 4. Among the effects of Aqua-Acupuncture of Palmijihwangtang water extract at the meridian point GV 4 group, water balance and urinary excretion of chloride, plasma levels of aldosterone decreased significantly over both 1 and 2 week period. Urine volume and urinary excretion of pottasium decreased significantly. Urinary excretion of creatinine and urinary excretion of sodium changed significantly over both 1 and 2 week period. Urinary excretion of free water clearance, plasma renin activity and plasma level of atrial natriuretic peptide showed no significant differences compared to the control group. Seeing these results, I come to know that the effects Aqua-Acupuncture of Yukmijihwangtang and Palmijihwangtang water extracts at the meridian point BL 23 and GV 4 have affected the renal function differently. Seeing the results that BL 23 is a meridian point for Aqua-Acupuncture directly related to the kidney, I think, we can use Aqua-Acupuncture of Yuk-mijihwangtang and Palmijihwangtang water extracts to prevent and to treat the diseases related to kidney.

• Advances in concrete construction
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• v.17 no.5
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• pp.257-271
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• 2024

During any construction involving mass concrete, it is crucial to control cracking during the placement and curing process. This study develops an intelligent cooling control system that regulates water temperature and flow based on concrete hydration heat, effectively preventing cracking in bridge construction. The system consists of hardware, a neural network-based control algorithm, and an information management system. An optimal cooling control strategy is proposed to dynamically regulate water flow and temperature, preventing cracking by utilizing real-time temperature data, target control curves, neural network algorithms, and cloud-based computing. The intelligent cooling control system has been successfully implemented in controlling cracking risks during bridge construction. It not only mitigates the risk but also provides a convenient management strategy for bridge construction projects. The optimal cooling control strategy ensures high accuracy and stability under unsupervised learning conditions. This intelligent cooling control system can be applied to similar constructions such as bridge, dam, and building that involve the use of mass concrete.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.4
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• pp.113-120
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• 2015

The objectives of this study were to monitor and assess the effects of saline irrigation water on lettuce and carrot growth in protected cultivation. One control and 4 treatments with three replications, which were differentiated according to the level of salinity in irrigated water, were employed for each vegetable to assess the effects of the irrigation with saline water. Monitoring results showed that the use of irrigation water containing above a certain level of salinity was found to cause excessive accumulation of salts in the soil as saline irrigation water increased electrical conductivity (EC) and sodium ($Na^+$) content in both lettuce and carrot soil samples, while tap water irrigation used as control decreased the salinity in the samples. The salinity higher than the threshold level of irrigation water was found to reduce the yields of lettuce and carrot, while in less than the threshold level the higher the salinity of the irrigation water increased the yields. The salinity of the irrigation water also appeared to increase the internal salinity of the plant as the $Na^+$ content in plant increased as the salinity of irrigation water increase. Increased $Na^+$ content was analyzed to be able to increase the sugar content in carrot. This study could contribute to suggest water quality criteria for safe use of saline water in protected cultivation, although long-term monitoring is needed to get more representative results.