• Solar Energy
• /
• v.5 no.2
• /
• pp.20-27
• /
• 1985

The aims of this study is to examine closely the temperature distribution of the solar pond for conditions of Seoul area climate and to prove capability of the solar pond utilization in Seoul area. In this study the equations for the convecting zone temperature of the solar pond were derived from Rabl and Nielsen's model. As the result of computer simulation, it was found that the average temperature of convecting zone is over $100^{\circ}C$ under conditions which is no output and 120cm depth or over of the insulating layer. Consequently if solar pond is constructed in Seoul area, it is a effective heat storage system.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.45 no.6
• /
• pp.194-206
• /
• 2003

A pilot study was performed to examine the feasibility of the pond system for further polishing of treatment wetland effluent to agricultural reuse of reclaimed water. The constructed wetland and pond system was installed in Konkuk University and the effluent from septic tank of school building was used as an influent to the wetland system. The effluent of the wetland was used as an influent to pond systems. The influent concentrations of total coliform(TC), fecal coliform (FC), and E. coli were about $10^5$MPN/100 ml, and they were reduced to less than 10,000 MPN/100 ml on average after wetland treatments, showing over 95 % removal. And they were further reduced to less than 1,000 MPN/100 ml in average, showing over 85∼93 % removal after pond treatment. Turbidity and SS were improved effectively on average and their pond effluent concentration was about 4.5 NTU and 9.8 mg/L in average, respectively Average $BOD^5$ concentrations were also reduced substantially to 9.3 mg/L with about 83 % removal rate after wetland and pond treatment systems. Nutrients removal was relatively low and removal rate for T-N and T-P was less than 43 and 44%, respectively after wetland and pond treatment. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, pond system was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water. This paper describes a preliminary result Iron pilot study and further investigations are recommended on the optimum design parameters before full scale application.

• Asian Journal of Turfgrass Science
• /
• v.18 no.2
• /
• pp.77-95
• /
• 2004

This study was conducted to find out definition, specification and characteristics of water-proof method for pond at golf courses that located in the mountain in Korea. Water-proof method of pond was selected by location, kind of soil, area, depth, cost, construction period and so on. 1. Soil Bentonite Sealing Liner(SBL) is to mix soil with a good quality bentonite. Then the mixed material was dressed on the bottom of pond. $\\$Merit of SBL is to purify the water and planting is possible. It can also reduce construction period and is economical. It's easy to find out the leak points. Demerit of SBL is expensive, if good quality soil is not in constructing site. Shape of pond edge is simple. 2. Ethylen Propylene Diene Monomer Sheef(EPDM-Sheet) makes use of sheet that resists to acid and alkaline. EPDM-Sheet spreads out as a mat on the pond for water-proof. Merit of EPDM-Sheet is to perfectly prove water and make a diverse shape of pond edge. Demerit of EPDM-Sheet is not friendly to environment. It needs drain system, air ventilation and long period of construction. It is also difficult to find out leaking points in this method. 3. Water proof of ESS-13 uses ESS-13 that is resin of vegetable matter and friendly to environment. To prove water of pond, ESS-13 is delicate with water in the pond. After that, Ess-13 in the water is expanded at pore space in the soil and cover with soil. ESS-13 can be to prove a leaking pond in golf course under business. ESS-13 is cheap and it needs short construction period. It does not need to switch the old water-proof system, additionally. It needs to move fishes to other place before utilizing ESS-13.

• Journal of Advanced Marine Engineering and Technology
• /
• v.40 no.4
• /
• pp.264-269
• /
• 2016

This paper reports a fundamental study of temperature characteristics of a solar pond with an insulation layer. Further, these characteristics were compared with those of a solar pond without the insulation layer. The governing equation was discretized via finite difference method. The governing equations are two-dimensional unsteady-state second-order partial differential equations. The conclusions of the study are as follows: 1) If the depth of the solar pond was increased, the desired effect of increase in temperature was not produced because the amount of solar insolation received by the bottom of the solar pond decreased. 2) As the temperature of the soil during winter is higher than the temperature of the water in a solar pond, heat was transferred from the soil to the solar pond. 3) For the case of the solar pond with insulation layer, it was estimated that the dependence rate of solar energy was 83.3% and that of the boiler was 16.7%.

• Korean Journal of Ecology and Environment
• /
• v.35 no.2 s.98
• /
• pp.133-140
• /
• 2002

This study was performed in lab scaled oxidation pond. The removal efficiency of pollutant on the influence of changes of hydraulic retention time and pond style was investigated. The correlation between organic removal efficiency and dissolved oxygen concentration on algal photosynthesis showed the light time revealed a higher relationship more than the dark time, and the squares of the correlation coefficient of 15 days retention time were higher than that of 5 days in single pond. The variation of dissolved oxygen concentration of a series pond was from 4.2 to 19.8 mg/l under 5 days retention time, the concentration of dissolved oxygen increased with increasing step of series pond. Between the single pond and a series of pond system, a series of pond system showed better organic removal efficiency. Average removal efficiency range of $TBOD_5$ and $SBOD_5$ was $49{\sim}83%$ and $87{\sim}92%$, respectively. Algae should be removed appropriately to increase the removal efficiency of organic matter.

• Solar Energy
• /
• v.7 no.2
• /
• pp.22-29
• /
• 1987

This paper dealed with thickness variation of bottom heat sotrage zone due to salinity and flow rate of extration hot brine in small test solar pond (0.5m wide, 0.5m high, 1.0m long). Testing apparatus and situation were follows: 7.1 cm of height of suction diffuser and 1.8cm of height of discharge diffuser above the test pond respectively, 0.3cm of slot size of suction diffuser, 1.0cm of slot size of discharge diffuser, 47cm of length of the slot; heating of hot water ($75^{\circ}C$) through separated hot water tank, discharge of the brine into storage zone through discharge diffuser, the extration of the brine through suction diffuser, circulation of the extracted brine through a heat exchanger (cooler). Following results were obtained through the experiments. 1. In small test solar pond, the typical three zone which showed up in real solar pond were established. 2. Richardson Number was used more effectively to confirm hydrodynamic stability of the stratified flow. 3. The thickness of non convective layer had a great effect on the heat storage of the bottom convective layer, then the temperature of bottom convective layer had a relation to that of upper convective layer. 4. Optimum operating condition in the test pond was on 10%-15% of salt concentration and $0.05m^3/hr$ of flow rate of extraction hot brine. 5. Following thickness of 3 zones were available to obtain under optimum operation condition: o bottom storage zone: $30%{\pm}10%$ of total pond depth o non-convective zone: $40%{\pm}10%$ of total pond depth o Upper surface zone: $20%{\pm}10%$ of total pond depth.

• Journal of Plant Biology
• /
• v.25 no.3
• /
• pp.123-133
• /
• 1982

The tropic structure and the function of a small pone ecosystem under the tree stand were studied in terms of energy flow. About 28% of total solar radiation was intercepted by the tree canopy over the pond. Primary producers converted 1.1%(3,382 kcal$\cdot$$m^{-2}$$\cdot$$y^{-1}$) of solar radiation (320,000 kcal$\cdot$$m^{-2}$$\cdot$$y^{-1}$) into gross primary production. The amount of energy availble to the pond snail was 1,683 kcal.m-2.y-1 of the net production by primary producers and 1,033 kcal$\cdot$$m^{-2}$$\cdot$$y^{-1}$ of the litter fallen into the pond. The amount of gross secondary production by the pond snail was 245 kcal$\cdot$$m^{-2}$$\cdot$$y^{-1}$. Judging from these, supply of both net primary production and the litter was indispensable for the maintenance of the pond ecosystem. The total amont of energy as gross primary production plus litter was 4,415 kcal$\cdot$$m^{-2}$$\cdot$$y^{-1}$(100%). Since the total respiration loss was calculated to be 1,917 kcal$\cdot$$m^{-2}$$\cdot$$y^{-1}$(43.4%), the rate of energy accumulation in the pond estimated to 56.6%.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.2
• /
• pp.1-11
• /
• 2015

This study sheds light on a pond design process which is a core facility of Hwaseol-dang in Muan, the Jeonnam. The plasticity of the pond was analyzed and interpreted for the design process using methods such as "literature search, interview, site visits, aerial pictures, aerial photographing, drawing figures of configuration plane via measurements, internet search, etc.", to trace the developing process of the design and the implications therein. The study results being centered on the developing process of the pond design are summarized herein below. The position of the Hwaseol-dang, being formed on a low hill having low competence as a place for a pavilion, draws more attention regarding its implications from the aspect of inner design. The pond Hwaseol-dang is in a rectangular shape of 1 : 1.2 ratio, in which the depth is a bit higher on the pond edge of the Hwaseol-dang thus being slanted, and Crape Myrtle, which is not known whether introduced during the formation of the pond, is cultivated on the island in the center widespread toward the southeast region. The planar design of the pond is interpreted as "rectangular pond" but it has a smooth half-moon shape where a part is excluded to remove edge. In particular, the three islands in rectangular pond, due to the narrow area, put one island and two half-moon-shaped islands in juxtaposition, and thus, although only being one island, resultantly exhibits the existence effect of proliferated three islands. This is allegedly due to the intentional formation aiming at the effect of hybrid while minimizing the overlap due to merging and adding from the aspect of constituting a design. Furthermore, the pond Hwaseol-dang is extended northwest along with Hwaseol-dang, and also the island in the center is thought to additionally have one or two, but the widespread phenomenon of the island in the center appears to consider the effect of "sit view on the floor of the pavilion of Hwaseol-dang". Considering that even a few examples of ponds having the three islands among the private house gardens in the nation are all curved ponds, the characteristics of the rectangular Hwaseol-dang pond establishing the garden effect of the three islands by modifying the one island in rectangular pond is highly notable. Considering that the three islands of "Yeongju, Bangjang, and Bongrae" is the original shape of the pond garden gestating Taoist ideology, as a symbolic design of a pond, it is regarded as the characteristics of the pond shape in Jeonnam area, and the so-called three treasures "Hwaseol-dang, Camellia, and oddly shaped stones, etc." are concentrated as the symbolism of Hwaseol-dang pond.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.35 no.2
• /
• pp.1-14
• /
• 2017

The purpose of this study is to understand the environmental traits and significance of the pond place that appears in historic maps in 'Dongchon(東村)', which is the eastern section within the fortress wall of Hanyang. We reviewed various documents and maps to identify the name of the pond, and of those materials we followed the name provided by official national records and geographical titles to designate it 'Eouidongji Pond(於義洞池).' The results of the research showed, first, that from the standpoint of location and environmental characteristics, that the area of the Eouidongji Pond was an area that contained a pastoral atmosphere within the city. It was located in an area where the waters flowing from the mountains gathered, and the boundaries of the pond would change based on water levels within a plot of land about 2,000pyeong(app. $6,600m^2$) in size. Second, when seen from the perspective of its creation background, the Eouidongji Pond seems to have been a naturally occurring pond which was modified when the water system was managed in the city at the beginning of the dynasty. In addition to its role as a reservoir, it was operated as a lotus pond(蓮池) to offer lotus(蓮) related by-products. With the nearby detached palace being actively used, it seems the pond was managed at the same time. The pond had already been filled in by the early 20th century, and although there were efforts to reconstruct the pond, it was eventually destroyed as the area was included in the site of a school during the colonial period. Third, the Eouidongji Pond was appreciated in many cases by individuals or admired as part of the natural landscape by viewing it from afar. In addition, it provided entry landscape near the road entering Dongchon, and was a location that was easily visited in connection with other nearby pleasure grounds. Through studying the location and environmental characteristics, the background of its creation and destruction, operation and management by time period, usage at the time, and characteristics of scenery appreciation of Eouidongji Pond, the Eouidongji Pond was a pond of high practical value to the nation, as it supplemented the water system in the city and was able to provide lotus harvests for the nation. In addition, from a urban environment perspective, it was a lateral landmark with a large area, as well as an effective boundary. It was an open area that the people of the Hanseong-bu could freely use, and it had a high public value due to its ease of accessibility.

• Economic and Environmental Geology
• /
• v.48 no.6
• /
• pp.467-475
• /
• 2015

The Deokjin Pond is one of the places representing Jeonju City's history but has the poor water quality. The pond has a storage of $88,741m^3$ and a drainage area of $3.77km^2$. It has been maintained only by the groundwater pumped from the upstream wells and the direct rainfalls on the water surface since the old streams replenishing the pond were turned into a part of the sewer system due to indiscreet urbanization. The lack of replenishing water as well as the organic-rich bottom sediment were suggested as two main causes deteriorating the water-ecosystem. In this study, possible measures obtaining waters for restoration of Deokjin Pond ecosystem are discussed. It is estimated that the present pond can be replenished about 32 times a year by the runoff when the drainage system in the watershed is recovered to a state before urbanization. To support this, the drainage system is compared with that of nearby Osong Pond, which shows relatively better water-ecosystem. Even though Osong Pond has a drainage area one-seventh of that of Deokjin Pond, its storage is more than the half of it. It is because its watershed has a near natural drainage system where the rain mostly infiltrates into soil and slowly discharges into the pond. Therefore, it is believed that the low impact development (LID), which is known as a technique restoring the water circulating system to a condition before development, would be helpful in obtaining waters required for Deokjin Pond ecosystem management.