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

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.4
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• pp.139-148
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• 2002

Pilot study was performed to examine the feasibility of the pond system for further polishing of treatment wetland effluent from December 2000 to June 2001. The wetland system used for the experiment was highly effective to treat the sewage during the growing season, but it was less effective and its effluent was still high to discharge to the receiving water body. Therefore, the wetland effluent may need further treatment to prevent water quality degradation. Pond system could be used to hold and further polish the wetland effluent during the winter season and ots feasibility was evaluated in this study. Additional water quality improvement was apparent in the pond system during winter season, and the pond effluent could be good enough to meet the effluent water quality standards if it is properly managed. Timing of the pond effluent discharge appears to be critical for pond system management because it is a closed system and whole water quality constituents are affected by physical, chemical, and biological pond environments. Once algae started to grow in mid-April, constituents in the pond water column interact each other actively and its control becomes more complicated. Therefore, upper layer of the pond water column which is clearer than the lower layer my need be discharged in March right after ice cover melted. In the experiment, water quality of the upper water column was markedly clear in March than ant other times probably because of freezing-thawing effect. The remaining lower water column could be further treated by natural purification as temperature goes up or diluted with better quality of wetland effluent for appropriate water uses. This study demonstrated the feasibility of pond system for subsequent management of wetland effluent during the winter season, however, more study is needed for field application.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.399-404
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• 2010

A hydrogen-producing bacterium (strain ES392) was isolated from pond water located in the Dong-Eui University, Busan, Korea. The cell was long-rod type ($1.4\;{\mu}m$) of about ($0.6\;{\mu}m$) in diameter, and not formed flagellum and spore. Phylogenetic analysis based on the 16S rRNA sequence and biochemical studies indicated that ES392 belonged to the genus Enterobacter sp. The optimum pH and temperature for hydrogen production was 7.5 and $35^{\circ}C$, respectively. The optimization of medium compositions which maximize hydrogen production from Enterobacter sp. ES392 was determined. As a result, the maximum hydrogen production was obtained under the conditions of 4% (w/v) sucrose, 0.5% (w/v) yeast extract and 50 mM potassium phosphate buffer (pH 7.5). Under batch culture conditions, the maximal hydrogen production and yield were obtained as 3481 mL/L and 1.33 mol/mol sucrose, respectively.

• 한국과학기술학회:학술대회논문집
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• 2015.12a
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• pp.313-326
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• 2015

데카르트는 사후에 출간된 1662년 "인간론"에서 자동기기의 유압체계모델을 이용하여 인간신체의 신경기능과 근육운동에 대하여 기계론적 설명을 제시하였다. 이것은 바로크 과학기술의 자동기기의 유압체계를 모델로 근육운동이 동물영혼에 의한 신경 전달로 진행된 것을 보여준 실험이었다. 근육운동은 동물영혼에 의한 신경 전달로 진행될 때 이를 기계론적으로 잘 설명될 수 있다고 본 데카르트의 동물영혼에 관한 견해는 출간 이후 3년 만에 네덜란드 자연학자, 해부학자, 현미경학자, 철학자 슈밤머담(Jan Swammerdam 1637-80)이 도전하였다. 그는 1664년 12월 8일 보르흐 앞에서 마취 없이 살아있는 개구리의 심장을 해부하고 두뇌 제거하는 전극실험으로 개구리의 근육운동이 데카르트가 가정하는 동물영혼과는 무관하다는 것을 보여주므로 반박하였다. 슈밤머담은 이 실험 이전에도 이미 라이덴 대학에서 여러 가지 실험으로 명성을 쌓았고 이 실험으로 해부학과 생리학의 출발을 알렸다. 뢰벤훅은 1673년 270배 확대 렌즈를 측정 대에 설치하여 눈에 가까이 갖다 대 고착시킨 첫째 동물이라는 뜻의 박테리아(${\pi}{\rho}\acute{\omega}{\tau}o$ ${\zeta}\acute{\omega}o{\nu}$)를 관찰하였다. 대학에서 전공하지 않았다는 비전문가로서 뢰벤훅이 이 연구에 뛰어들게 되는 것은 바로크 과학기술문명에 중요한 의미를 지닌다. 그라프는 그해 4월 왕립학회에 그가 빗물이나 연못물에서 채취하여 관찰한 미생물을 1677년에 아니말쿨레스(animalcules)라 불렀다는 것을 알렸고 이 관찰은 나중에 왕립학회 검증으로 확증되었다. 뢰벤훅이 명성을 얻게 된 것은 그라프가 그를 학문적으로 이끌어주었기 때문이다. 뢰벤훅에서 광학수업을 받은 하르췌커는 1694년 현미경으로 인간정액을 관찰하는 동안에 하르췌커는 정액 내에 수많은 아니말쿨레스로서 호문쿨리(homunculi)가 살고 있는 것을 보고 그 존재를 요청하였다. 하르췌커는 정규 학문과정에서 성장한 전문가로 뢰벤훅에서 렌즈닦는 기술을 습득하므로 정액주의 운동의 첨단에서 주목을 받게 되었지만 대중적 인기에 영합하였다. 이 발표는 17세기 후반 슈밤머담과 뢰벤훅이 실험철학에 기초한 곤충과 동물 및 미생물 세계의 연구 성과를 과학과 윤리 혹은 신학과의 상보적 관점에서 개관하고, 이들 연구방법을 이신론과 수사학의 입장에서 해명하고자 한다. 17세기 후반에 곤충학의 대가인 슈밤머담과 하르췌커에서 동물생성의 문제에 이신론의 물음은 물질과 정신과의 관계를 해명하려는 과학과 신학과 철학의 경계의 물음이다. 이 경계에서 이신론의 수사학적 접근은 개별분과에서 해결하지 못한 중요한 아포리아를 풀어가는 인문학적 역할에 기여를 할 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.8
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• pp.761-766
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• 2010

This study was aimed to propose La(III)-zeolite composite which can effectively and simultaneously remove ammonia and phosphate in confined water bodies such as lakes and ponds. The optimum ratio of La(III):zeolite for the simultaneous removal of ammonia and phosphate was 0.0048 La(III) g:1 zeolite g. The drying temperature of La(III)-zeolite composite severely affected phosphate adsorption showing optimum condition at room temperature. It was revealed that the optimum dosage of La(III)-zeolite composite was 4.052 g/L at adsorption time of 90 min. The presence of alkalinity in aqueous solution brought positive effect on phosphate adsorption. Detachment of La(III) from La(III)-zeolite composite, which was dried at room temperature, was not observed in aquous solution. It indicates that La(III)-zeolite composite could effectively block phosphate released from sediment.

• Korean Journal of Environmental Agriculture
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• v.23 no.4
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• pp.234-239
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• 2004

[ $NO_3$ ]-N and T-N removal rates of cattail wetland cells were compared with those of reed wetland cells. The examined cells were a part of a pond-wetland system composed of two ponds in series and six wetland cells in parallel. Each wetland cell was 25m in length and 6m in width. Cattails (Typha angustifolia) were transplanted into three cells and reeds Phragmites australis) into another three ones in June 2000. Water of Sinyang stream flowing into Kohung Estuarine lake located in the southern part of the Korean Peninsula was pumped into the primary pond, its effluent was discharged into the secondary pond Effluent from the secondary pond was funneled into each cell. Two cattail and reed cells were chosen for this research. Water quantity and quality of influnt and effluent were analyzed front May 2001 through October 2001. The volume of influent and effluent of the cells averaged about $20.0\;m^3/day$ and $19.3\;m^3/day$, respectively. Hydraulic retention time was approximately 1.5 days. Influent $NO_3$-N concentration for the four cells averaged 2.39 mg/L. Effluent $NO_3$-N concentration far the cattail and reed cells averaged 1.74 and 1.78 mg/L, respectively. Average $NO_3$-N retention rate for the cattail and reed cells by mass was 30 and 29%, respectively. Influent T-N concentration far the four cells averaged 4.13 mg/L. Effluent T-N concentration for the cattail and reed cells averaged 2.55 and 2.61 mgL respectively. Average T-N retention rate for the cattail and reed cells by mass was 39 and 38%, respectively. $NO_3$-N and T-N concentrations in effluent from the cattail cells were significantly low (p=0.04), compared with those from the reed cells. Cattail wetland cells were more efficient for $NO_3$-N and T-N abatement than reed ones.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.13-24
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• 2014

The pond wetlands in agricultural landscape are important natural resources that carry out the function of bio-diversity conservation. However, recently, those have been gradually embedded as their utility value were disappeared. And, the assessment methods used for pond wetlands are insufficient. Therefore, this study was conducted to examine the conservation value of pond wetlands by using the modified RAM, and present the improvement of assesment methods. The study sites, a total of 32 pond of 4 types by land use, were selected on the basis of Ramsar Convention. Through the analysis of precedent studies, the weighted 8 functions were adjusted. According to the assessment results, pond wetlands made the largest contribution to Fishery and Herpetile Habitat function. In addition, it also made large contribution to Floral Diversity, Wildlife Habitat, and Water Quality Protection function. On the other hand, it made a small contribution to Aesthetics and Recreation, Runoff Attenuation, Shoreline /Stream Bank Protection, and Flood/Storm Water Storage function due to the characteristics of small-scale pond wetlands. In the assessment of 8 functions, house type showed the worst assessment result, and mountain type showed the best assessment result. It is thought that those are due to land use type in terms of vicinity. 10 items among 52 of the modified RAM showed the same assessment results in all land use types. Accordingly, it is required to be deleted and modified the assessment method. On the other hand, it is required to add age, interference, and water use to the assessment method. It is thought that these results can be utilized for the development and modification of assessment methods focused on pond wetlands in rural area.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.475-481
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• 2006

The major problem in closing water like lakes and ponds in Korea is that because they are exposed to surrounding, so easily polluted. The pollution in closing water can be caused by not only artificial factor like sewage but also natural factor like elution from sediment. For insurance of safe and satisfied water source, lots of studies and projects are now going on. In this study, we examined the behavior and effect of microbubble ($3{\sim}10{\mu}m$) produced by device called O.S.D (Oxygen Solubillization Device) in small size pond. The value of oxygen transfer coefficient ($K_La$) was 0.68/min independently of air flow rate, 6.5 times higher than commercial aeration stone and the variation of nitrogen concentration was $0.008NO_3/O_2$, DO concentration was potentially saturated for 24 hr. From the results of pilot plant, SOD of experiment (O.S.D) and control were $12.18gO_2{\cdot}m^{-2}{\cdot}d^{-1}$ and $47.95gO_2{\cdot}m^{-2}{\cdot}d^{-1}$ respectively. In conclusion, because O.S.D has extraordinary physico-chemical characteristics, it can contribute to improvement of both the waterbody and the sediment environment.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.324-330
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• 1987

A large number of methanol-assimilating yeasts and bacteria were isolated from samples of soil, sewage, decomposed milk and spoiled sweet-radish pickles. Among the yeasts, one strain was selected and identified as a strain of Candida boidinii. In 1% (v/v) methanol Candida boidinii YF-3 grew well and could grow in as much as 5%. This yeast required boitin for grwoth. Maximum growth was observed at $30^{\circ}C$ and pH 6 in a semisynthetic medium. The productivity was 2.72g dry cells per liter in batch culture with 1%(v/v) methanol and the cell yield for methanol was $0.39\;gg^{-1}$. The specific growth rate was $0.11\;h^{-1}$ and the generation time was 6.4 hours. The protein content of the cell was 45.5% and total nucleic acid content was 5.9%. The amino acid profile was as good as FAO standard for food protein.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.477-482
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• 1998

In the aquaculture industry, a photobioreactor (Pbr) with high productivity is a prerequisite for mass production of Chlorella sp., a feeding fry for Rotifer (Brachinous plicatilis). To enhance the productivity of Chlorella sp., model Pbrs such as Cylinder type, Spherical surface type, Half-spherical surface type, Plate type, Raceway pond type and Water-wheel type Pbr with different values of surface area exposed to light/culture volume (S/V) were manufactured, and the maximum specific growth rate (${\mu}_{max}$) and productivity of Chlorella vulgaris 211-11b at $25^{\circ}C$, pH 7.0 and 12,000 lux were compared each other. The ${\mu}_{max}$ and productivity were not proportional to S/V. Among the 6 model Pbrs, Half-spherical surface type Pbr showed the highest ${\mu}_{max}$ and productivity as 2.206 ($day^{-1}$) and 0.247($g^{{\ell}-1}day^{-1}$).