• Title/Summary/Keyword: pond

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A Study on Chinese Ancient Garden -focus on Qin, Han, Sui, Tang Dynasties- (중국 고대 원림에 관한 연구: 진, 선한, 수, 당대를 중심으로)

  • 박경자;양병이
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.2
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    • pp.119-129
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    • 1999
  • It may be said that ancient wild Chinese garden had been founded during Qin dynasty and completed through Han, Sui and Tang dynasties. At first used as hunting areas for kings, the ancient resort forests began to take forms of garden. They dug a pond in the garden and made a simulated mountains with the soil that came from the excavations for the pond and suc pavilions has Gyong, Ru, Gak etc. were built around the pond. The ponds were different in size from those in Korea, being of the lake-like size. they made three island in the pond, which were the islands of Taoist hermits with supernatural powers, called Bong-lae, Young-ju and Band-jang respectively. the traditional of making those islands began in the Qin era and were completed in the Han era, being descended to posterity as a traditional garden structure of 'three islands in one pond' garden style. Such style was brought to Korea and first appeared as Kung-Nam-Ji in Back-jae kingdom and then brought to Japan, becoming the tradition of constructing ponds from early Heian era. Those lake-like huge Chinese ponds constituted the core of ancient garden where various feasts took place. Such ponds were also placed at the center of the gardens and played the roles of feasting garden ponds. Through the above-mentioned studies of the ancient Chines garden, the origin of them and the influence of the ancient Chinese ponded garden upon those of Korea and Japan were investigated.

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Comparison of Rheological Properties of Powder Chlorella sp. Cultivated in Fermentor and Pond

  • Kang, Ki-Rim;Lee, Chung-Yung-J.;Lee, Cherl-Ho
    • Journal of Microbiology and Biotechnology
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    • v.12 no.5
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    • pp.740-745
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    • 2002
  • The current study was conducted to identify the differences in the rheological properties of Chlorella sp. powder cultured in a fermentor and in a pond-like environment. Cells. cultured in the same media were harvested and spray dried. The biomass yield from the fermentor culture was 4.7% (dry basis), while that from the pond was 4.3% (dry basis). Measurements of the loose bulk density, tapping test, Hausner's ratio, and compressibility test all revealed differences between the rheological properties of the Chlorella sp. from the two cultivation systems. Although both the fermentor and pond cultured Chlorella sp. showed the same angle of repose, the mean size of the cells was 2.26 $\mu\textrm{m}$ and 2.89 $\mu\textrm{m}$, respectively. The weight of the Chlorella sp. tablets cultured in the fermentor and pond was 0.663 g/tablet and 0.593 g/tablet, respectively, while the friability of the tablets was 21% and 41%, respectively. Observation by Transmission Electron Microscope (TEM) showed that the cell wall of the Chlorella sp. cultured in the fermentor was thinner and more spherical than that cultured in the pond, thereby providing the main characteristic rheological properties of the powder.

Behavior of GGBS concrete with pond ash as a partial replacement for sand

  • Maheswaran, J.;Chellapandian, M.;Kumar, V.
    • Advances in concrete construction
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    • v.13 no.3
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    • pp.233-242
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    • 2022
  • An attempt is made to develop an eco-friendly concrete with ground granulated blast furnace slag (GGBS) and pond ash as partial replacement materials for cement and fine aggregate, respectively without compromising the strength and durability. Sixteen concrete mixes were developed by replacing cement and fine aggregate by GGBS and pond ash, respectively in stages of 10%. The maximum replacement levels of cement and fine aggregates were 50% and 30% respectively. Experimental results revealed that the optimum percentage of GGBS and pond ash replacement levels were 30% and 20% respectively. The optimized mix was used further to study the flexural behavior and durability properties. Reinforced Concrete (RC) beams were cast and tested under a four-point bending configuration. Also, the specimens prepared from the optimized mix were subjected to alternate wet and dry cycles of acid (3.5% HCl and H2SO4) and sulphate (10% MgSO4) solutions. Results show that the optimized concrete mix with GGBS and pond ash had a negligible weight loss and strength reduction.

State of Aquaculture Management for Optimal Rearing of Eel Anguilla japonica (뱀장어(Anguilla japonica) 적정 사육관리를 위한 양식기술 현황)

  • Son, Maeng-Hyun;Kim, Kang-Woong;Kim, Kyoung-Duck;Kim, Shin-Kwon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.4
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    • pp.359-365
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    • 2011
  • This study was conducted to investigate the production, elver stocking, rearing facilities and rearing method of eel culture to determine aquaculture management conditions for optimal rearing of eel Anguilla japonica. The production of eel culture was evaluated by the proportion of eels from the main inland fin fish species production in Korea. Elver stocking was assessed by the elver stocking densities of pond and recirculation culture. Rearing facilities were investigated according to the rearing tank size proportion of the pond and recirculation culture. We selected sample farms by region and by size. We visited sample farms and recorded the number of elvers stock for pond area, size of tanks, feed and feed quantity, and the size and number of harvest eels. The production capacity of Jeollanam-do and Jeollabuk-do were 71.9% and 21.3% respectively. This production quantity represented 93.2% of the total Korean eel production quantity. In Jeollanam-do, there are 236 eel farms, 202 pond farms, and 34 recirculation aquaculture facilities. The elvers' first density data by each aquaculture method revealed that elvers' first density varied more in recirculation system farms, as compared to pond aquaculture. In intensive pond farms, the elvers' first density decreased as the size of farm increased. There was a correlation between the size of tank(x) and the facility of a water wheel for dissolved oxygen in pond culture systems(y=0.022x-0.494; $R^2$=0.860). Another strong correlation was found between the weight of eel(x) and eel density(y) in pond culture systems(y=283.5x-0.27; $R^2$=0.992). Finally, there was a strong correlation between the length of eel(x) and the weight of eel(y) in intensive pond culture(y=0.0005x-3.2783; $R^2$=0.9775). The final survival rate did not differ significantly among pond sizes and culture types.

Analysis of Rainfall Runoff Reduction Effect Depending upon the Location of Detention Pond in Urban Area (도시유역 저류지 위치에 따른 우수유출저감효과 분석)

  • Lee, Jae Joon;Kim, Ho Nyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.5B
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    • pp.535-546
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    • 2008
  • Urbanization results in increased runoff volume and flowrate and shortening in time of concentration, which may cause frequent flooding downstream. The retardation structures are used to eliminate adverse downstream effects of urban stormwater runoff. There are various types of flow retardation measures include detention basin, retention basin, and infiltration basin. In this study, to present a rough standard about location of detention pond for attenuating peak flow of urban area, the runoff reduction effect is analyzed at outlet point when detention pond is located to upstream drainage than outlet. The runoff reduction effects are analyzed under the three assumed basins. These basins have longitudinal shape (SF = 0. 204), concentration shape (SF = 0. 782), and middle shape (SF = 0.567). Numerous variables in connection with the storage effect of detention pond and the runoff reduction effects are analyzed by changing the location of detention pond. To analyze runoff reduction effect by location of single detention pond, Dimensionless Upstream Area Ratio (DUAR) is changed to 20%, 40%, 60%, and 80% according to the basin shape. In case of multiple detention pond, DUAR is changed to 60%, 80%, 100%, 120%, and 140% only under the middle shape basin (SF = 0.567). Related figures and regression equations to determine the location of detention pond are obtained from above analysis of two cases in this study. These results can be used to determine the location of appropriate detention pond corresponding to the any runoff reduction such as storage ratio and peak flow ratio in urban watershed.

Analysis of Sediment Reduction Efficiency with Net Type Sediment Settling Pond at Highland Agricultural Region (그물망침사지를 이용한 고랭지밭 흙탕물 저감효과 연구)

  • Hyun, Geun-Woo;Park, Han-Kyu;Lee, Yong-Sik;Lee, Suk-Jong;Park, Jeong-Hee;Jun, Sang Ho;Choi, Jaewan;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.26 no.2
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    • pp.215-224
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    • 2010
  • This study was carried out to estimate effects of sediment reduction with net type sediment settling pond at highland agricultural areas. Flow and sediment monitoring system with rainfall gauge were installed at the study area for real-time monitoring and analysis. It was found that amount and intensity of rainfall events strongly affect sediment yield from the study area. With net type sediment settling pond, it was expected that approximately 61% of sediment could be removed. The correlation between heavy metals and SS were analyzed in this study. $R^2$ values were 0.644, 0.876, 0.945, and 0.928 for Fe, Mn, Al, and Si, respectively. This results indicate that heavy metals also could be removed with net type sediment settling pond. As shown in this study, the sediment settling pond will be an efficient sediment reduction facility at highland agricultural areas. For maximum reduction efficiencies of sediment and other pollutants at agricultural fields, simplified sediment settling pond should be designed and implemented.

A Development of Simplified Design Method of the Detention Pond for the Reduction of Runoff (우수유출저감용 저류지의 간편설계기법 개발)

  • Lee, Jae-Joon;Kwak, Chang-Jae
    • Journal of Korea Water Resources Association
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    • v.41 no.7
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    • pp.693-700
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    • 2008
  • Detention pond has an important role in peak flow reduction to mitigate flood damage. Design of detention pond is accomplished through the preliminary stage, and design stage in general. New development projects produce increased peak flow and flow amounts. In this case it is necessary to design the detention pond easily and simply. A simplified design method of the detention pond is suggested in this study. Used design variables are peak flow ratio(${\alpha}$) and storage ratio($S_r$). ${\alpha}$ is the peak flow ratio of before and after development of the basin. $S_r$ is a ratio of storage volume to total runoff volume. Applicability of the proposed method was also proved. The simple procedure of detention pond design is proposed in this study.

The Effect of Physical Design Parameters on the Constructed Wetland Performance (물리적 설계인자가 인공습지의 처리효율에 미치는 영향)

  • Ham Jong-Hwa;Yoon Chun G.;Koo Won-Seok;Kim Hyung-Chul;Shin Hyum-Bhum
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.5
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    • pp.87-97
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    • 2005
  • The field scale experiment was performed to examine the effect of physical design parameters on the constructed wetland performance and recommend the feasible design of constructed wetland in Korean polder areas. Four sets (each set of 0.85 ha) of wetland (0.8 ha) and pond (0.08 ha) systems were used. Two different wetland systems, a wetland-pond system and a pond-wetland system, were studied to examine the effect of wetland and pond configuration. And two different length-to-width ratios were used, 2: 1 and 0.8: 1, to examine the effect of aspect ratio. A pond-wetland system was more preferable than a wetland-pond system, and also requires a smaller area than a wetland-pond system or a wetland system to reduce T-P. There was no difference in effluent concentration between the 2:1 system and the 0.8:1 system. Although the linear velocity of the 2:1 aspect was higher than the 0.8:1 aspect, resuspension was not a factor in this study due to a very low linear velocity. From this study and other literature review, it was found that design method of paddy rice field could be applied and expanded to the design of constructed wetland in Korea. Further investigation for the detailed design parameters of constructed wetland needs be continued for design method of paddy rice to be applied in full scale.

The Placeness of Deokjin Park in Jeonju City (전주시 덕진공원의 장소성)

  • Kim Yun-Geum;Sung Jong-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.3 s.110
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    • pp.65-77
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    • 2005
  • Deokjin Park in Jeonju City was the site of a pond during the Koryo Period. Although Jeonju City has developed rapidly in modem times, Deokjin Pond was preserved and was developed into a park It can be theorized that Deokjin Pond's latent character has made it possible for it to adapt to the changes it has undergone throgh the years. In this study, the placeness of Deokjin Park is determined by examining its role in the adaptation process. Placeness can be determined by examining the objective character of a certain environment and the subjective experience related to it. For this paper, documents about the history of Deokjin Park were examined so that the facts related to it could be established. In addition, a number of Jeonju citizens were asked about their memories of Deokjin Park since memories reveal people's subjective experiences. The results of this study can be summarized as follows. Deokjin Pond is an ideal space for Feng Shui. It is a holy place because the tomb of the founder of the Chosun Dynasty is close to it. In addition, it has scenic value as it is part of the Jeonju Palkyoung (eight sceneries). To this day, we can see people washing their hair in the pond, proof that Deokjin Pond is still the subject of folk beliefs. When Korea was under Japanese rule, Deokjin Pond became Deokjin Park because of its ideal location, scenic value, and grand possibilities as an amusement center. Over the years, though its scenic value decreased after the death of its pine trees. Jeonju City, however, was able to revive the park's charm though a series of renovation projects and through the addition of several facilities. Deokjin Park is now surrounded by many cultural buildings. The significance of Deokjin Park can be expected to evolve with these changes. This study helps to predict the future of Deokjin Park and to elucidate the importance of landscape architecture from the point of view of an "evolving place."

A Comparison and Analysis of Planning Models for the Design of Detention Pond in Urban Area (도시유역의 저류지 설계를 위한 계획모형 비교분석)

  • Lee, Jae-Joon;Kwak, Chang-Jae;Lee, Sang-Won
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.3
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    • pp.105-115
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    • 2008
  • Urbanization results in increased runoff volume and peak flowrate and shortening in time of concentration, which may cause frequent flooding downstream. There are various types of flow retardation methods including detention ponds, retention ponds, and infiltration ponds. In general, hydrologic models to design the detention pond are classified into planning model and design model. This study is comparing and analyzing of planning model to design the detention pond in urban area. Detention ponds data of Disaster Impact Assessment Report on 22 sites were analyzed to investigate proper planning models in this study. From this research, following conclusions are derived, 1) In case of on-line detention pond, Lee model(1991) is the best planning model and similar to real storage volume. 2) In case of off-line detention pond, Abt and Grigg model is much more proper model compared to other models.