• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.1
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• pp.122-131
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• 1999

Indoor environments are usually less than optimal for the growth of ferns, especially in regards to the water condition. These studies were performed to investigate responses involved in causing growth of ferns and presume management plan against the water deficit under indoor conditions. The effect of air humidity and soil moisture on the ferns was examined in Adiantume raddianum and Selaginella kraussiana. Results of experiments are as follows; 1. Under a low humidity condition, having a 25-50% RH. ornamental value of ferns decreased much more than under a 90% RH. Under a low soil moisture, such as sand treatment, ornamental value of ferns also decreased. 2. Leaf chlorophyll content, water content and stomata situations increased as air humidity and soil moisture went up. 3. Even if air humidity and soil water were not enough for ferns growth, the extending of irrigation cycle was helpful. 4. Under extremely low air humidity conditions, some water management, namely, using water holding soil or extending of irrigation cycle was desirable. Other methods of increasing air humidity, including water instruments such as ornamental pools, waterfalls, or fountains, grouping plants together were also helpful. But spraying water on leaves increased injury to ferns growth because of excess evaporation from the leaves. Though these studies, we learn that ferns are susceptible to water condition such as air humidity, soil water and water management. If other environmental factos are maintained with optimal conditions, water condition plays an important role in ferns growth in indoor environments.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.507-514
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• 2009

In this study, a dynamic modeling scheme is presented to describe the probabilistic structure of soil water and plant water stress index under stochastic precipitation conditions. The proposed model has the form of the Fokker-Planck equation, and its applicability as a model for the probabilistic evolution of the soil water and plant water stress index is investigated under a climate change scenario. The simulation results of soil water confirm that the proposed soil water model can properly reproduce the observations and show that the soil water behaves with consistent cycle based on the precipitation pattern. The simulation results of plant water stress index show two different PDF patterns according to the precipitation. The simple impact assessment of climate change to soil water and plant water stress is discussed with Korean Meteorological Administration regional climate model.

• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.519-522
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• 2008

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.21-21
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• 2011

Many Asian countries are suffered from various problems on water, which include the need for increased access to improves water supplies and sanitation through investments in infrastructure and capacity building, the balances water management system between development and ecosystem, and the need to reduce the human populations'vulnerability to water-related disasters, in particular, from climate variability and evolution. Decison makers are the most influential people in policy making and solving global water problems is central issue in eradicating poverty and achieving sustainable development (MDG). They across the world form an integral part of the architecture of national or regional governance. Their role covers a range of decision-making processes including passing legislation, scrutinizing government policy, and representing citizen through the election. We must ensure that these quiet but important issues get the political space, financial priority and public attention they deserve. Regional bodies such as the EU have also enacted legislation which introduces rules on water quality and other enforceable mattera across state boundaries. With this growing body of laws and policies on water issues, the role of decision makers is growing. Recognizing this role, decison makers' platform is essential to provide an opportunity to discuss crucial water issues in each country or region and for the purpose "2010 Parliaments for Water in Asia" has planned and organized to investigate our common issues and goals. During the meeting, we have an opportunity to observe water policy of Bangladesh, Bhutan, China, Mongolia, New Zealand and the Philippines and share the views on what needs to be done to move forward by decision makers for the future of water. In conclusion, the process of developing the decision makers' platform in each region would be ultimately essential point to increase the awareness of the developed and developing countries' roles, knowledge to clarify roles and responsibilities of each stake holders and finally be a major actor for resolving not only water challenges also issues of human settlements.

• Journal of Korean Society on Water Environment
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• v.33 no.5
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• pp.525-530
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• 2017

The attainment ratios of the water quality goals of the 114 mid-watershed representative stations, examined during the period2011 to 2015, were evaluated in the study. Of the four major river basins, the attainment ratio on water quality goal of the Geum River basin turned out to be the lowest. As a result of formal evaluation of the attainment ratios of BOD, COD and TOC, it was found that the attainment ratio of COD was much lower than that of BOD and TOC (I a circumstance thought to be caused by the higher COD/BOD and COD/TOC ratios of the water quality of the river than those of the environmental water quality standard). As well, higher COD/BOD and COD/TOC of wastewater discharged from point and non-point sources (other than those of the environmental water quality standards) might possibly represent one of the reasons. We also compared attainment ratio between the main stream and tributaries, which indicated that the higher attainment ratio was present in the main stream. The attainment ratio is also documented as more significant in the winter season than the summer season, possibly due to the contribution of non-point pollutants swept in by rain during the summer season during documented periods of high precipitation. Thus, water quality management in summer season and improvement of water quality of the tributaries might be important as a means of increasing attainment ratio on water quality goal.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.7
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• pp.14-24
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• 2002

The effect of reclaimed water irrigation on paddy rice culture was evaluated by pilot study at the experimental field of Konkuk University in Seoul, Korea. The sewage was treated by constructed wetland system, and its effluent was used as irrigation water for four treatments and one control plots with three replications. Irrigation of reclaimed water onto paddy rice cultures did not adversely affect the growth and yield of rice. Instead, experimental rice plots of reclaimed water irrigation displayed about 10 to 50% more yield on average than controls. This implies that reclaimed water irrigation might be beneficial rather than harmful to rice culture as long as the sewage is treated adequately and used properly. The amount of irrigation water had little effect on experimental rice cultures, but its strength was important. The strength of treated sewage was not a limiting factor in this study, and no lodging was observed even with a relatively high nitrogen concentration (up to 160mg/L). In general the paddy soil was not affected by reclaimed water irrigation. However, there was an indication that continuous irrigation with high strength of reclaimed water might cause salt accumulation in the soil. Supplemental use of reclaimed water with existing sources of irrigation water is recommended rather than irrigation with a single source of reclaimed water. Overall, the results demonstrated that reclaimed water could be reused as a supplemental source of irrigation water for paddy rice culture without causing adverse effects as long as it is properly managed. For full-scale application, further investigation should be done on environmental risks, tolerable water quality, and fraction of supplemental irrigation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.12
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• pp.802-807
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• 2008

A Study on Typical Rates of Water-use for School Facilities has been carried out in this work. Water supply system is given much weight in school facilities. Therefore, it set up a basis efficiency using of water sources to calculate typical rates of water use. The results are summarized as follows; 1) On the whole, typical rates of water-use was founded out 15 L/stu. d in pirmary school, 10 L/stu. d in middle school and 30 L/stu. d in high school smaller than the existing it. It was rate of water-use change as season and Max. Rates of water-use was July. 2) I deem that school hours are 5 hour's in primary school, 7 hour's in middle school and 8 hour's in high school. It the concept of 1 hour that is lesson time 40 minutes and resting time 10 minutes in primary school, lesson time 45 minutes and resting time 10 minutes in middle school and lesson time 50 minutes and resting time 10 minutes in high school. 3) It is desired that we calculate the volume of pump and water tank throughout this concept and the size of water tank should be 1.5 times with taking peak load into consideration by this study on typical rate of water-use. 4) The amount of using water increases in gradually and I consider the life cycle of facilities is more than 10 years. As a result, I can forecast that the size will be insufficiency but I deem that if we devise a plan about parallel pumping on water tank space, we can cope with it. Also, it is expected that we can cut back the transport energy by controlling pump volume.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.2 s.115
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• pp.9-15
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• 2006

Neutral sizing is required for linerboard to solve the troubles in strength and process caused by recycled raw materials. AKD sizing efficiency can be influenced by process condition like white water quality, fines retention and so on. Therefore, this study was aimed to evaluate sizing performance of general and fast cure type AKDs using process water obtained from linerboard mill. To evaluate effect of process water quality on AKD sizing, white water was diluted with tap water at the different dilution ratios and UKP slurry was sized using the prepared water. Also, effects of inorganic and organic ion material on sizing were examined. When white water was used for stock forming, UKP sheet showed very low sizing degree. Sizing degree of sheet was increased with increase of dilution ratio because water quality was improved. Especially anionic organic material had a greater influence on AKD sizing than inorganic material. When white water quality was deteriorated, fast cure type AKD showed superior sizing performance to general type AKD.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.4
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• pp.90-95
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• 1989

The purpose of this study is to seek out the harrow water requirement applicable for the irrigation plan of paddy field and to find out the factors influenced on a variation in the requirement. The plots of experiment were arranged with randomized block design which was compo- sed of three kinds of soil texture (sandy loam, loam and silty loam) and ploughing depth (12cm, 17cm, and 22cm). The results obtained from this experimental study are summarized as follows. 1. Harrow water reguirement is not only changed by soil texture, but influenced by soil water content just before irrigating 2. Magnitude of total harrow water reguirement appli(able for the irrigation plan, when surface water depth and the water content just before irrigating is fixed on the basis of 30 mm and a shrinkage limit respectively, generally becomes to be 177.5mm, 116.3mm and 113. 8mm in the sandy loam, loam amd silty loam block, respectively. 3. The more a percolation of soil layer occurs, the more the harrow water requirement increases, but it is not much influenced by the increase in ploughing depth. 4. The larger a porosity of soil layer is, the more a net harrow requirement increases 5. The factors that influence on a variation in the harrow water requirement are appea- red to be percolation of soil layer, soil water content just before irrigating, porosity of soil layer, ploughing depth and designed surface water depth etc.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.819-828
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• 2011

This research was done to clarify the cooling effect of water particles generated from a fountain. This effect is a one way to control the heat island effect of big cities. The result of this research was drawn by setting the jets of water in a certain height, and then studying the diffusion of water particles, which is affected by the size of the particles and the wind speed, and the cooling effect caused by the diffusion. 1) When a diameter of a water drop was 500 ${\mu}m$ and the wind speed was 2.0 to 6.0 m/sec, the water drop diffused 75 to 190m, and the water vapor spread over 175 to 440 m. As a result, there was more than $0.5^{\circ}C$ of cooling effect on the temperature in the atmosphere 130 to 330m around the water fountain. 2) When a diameter of a water drop was 750 ${\mu}m$ and the wind speed was 2.0 to 6.0 m/sec, the water drop diffused 65 to 150 m, and the water vapor spread over 160 to 405 m. Moreover, there was more than $0.5^{\circ}C$ of cooling effect on the temperature in the atmosphere 110 to 275 m around the water fountain. 3) After studying on the relationship between the diameter of water drop and the wind speed, and the diffusion of water particles and the range of the atmosphere that was cooled, a result could be drawn from the research that the smaller the diameter of the water vapor gets and the faster the wind speed becomes, the wider the water particles diffuse and the cooler the atmosphere around the fountain becomes. 4) This research further extrapolates that when the ordinary water(tap water, water from river and stream) is used in a fountain, the cooling effect of the air near the fountain can be approached similarly. If the seawater is used in a fountain, there is to be more to concern not only on cooling effect on the air, but also on other effects on surrounding environment generated by the salt in seawater.