• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.206-206
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• 2020

토지이용의 고도화에 따라 비점오염원 부하는 증가하는 추세이며 기후변화에 따른 강우강도 증가 등으로 지표면에 축적된 고농도의 비점오염물질이 하천으로 유출, 수질오염을 가중시키고 있어 비점오염원 관리가 필요하다. 환경부에서 효율적인 비점오염원 관리를 위하여 2004년부터 현재까지 3단계에 걸쳐 비점오염원 관리 종합대책을 수행하고 있으며, 2008년부터 비점국고보조사업을 추진하여 비점오염저감시설 설치를 통한 수질개선 및 수생태계 건강성 확보에 기여하고자 하였다. 이에 본 연구는 비점국고보고사업을 통해 구축된 비점오염저감시설을 대상으로 시설 설치 및 운영 현황과 강우시 비점오염저감 효과 분석을 통한 시설의 평가를 수행하고자 한다. 연구대상시설은 시범시설 및 국고보조시설 총 70개소로 2005~2017년에 준공되었으며, 2016년부터 현재까지 총 4년동안 진행된 모니터링을 바탕으로 연구를 수행하였다. 시설의 용량은 34~97,000㎥의 범위로 SA/CA 1.2~6.6%의 범위이다. 강우시 모니터링은 선행무강우일수 3일이상을 고려하여 수행하였으며 도시지역의 경우 5mm 이상, 농촌지역 10mm 이상시 모니터링을 진행하였다. 시설의 유입과 유출부에서 수질 및 유량 모니터링을 진행하였으며, 수질오염공정시험법에 준하여 BOD, COD, SS, T-N 및 T-P 항목에 대해 분석을 수행하였다. 모니터링 결과, 국내 비점오염저감시설의 평균 부하량은 SS 250.4 kg/day, BOD 89.2 kg/day, COD 136.2 kg/day, TN 51.4 kg/day, TP 7.1 kg/day 로 분석되었으며, 유출부 의 경우 SS 83.8 kg/day, BOD 37.2 kg/day, COD 51.0 kg/day, TN 15.4 kg/day, TP 2.0 kg/day로 나타났다. 또한, 은 오염물질 유입 및 유출 부하량의 상관관계 분석결과 SS, BOD, COD의 유입 및 유출 부하량의 상관성은 높게 나타났으며 특히 유기물질(BOD, COD)의 상관성은 0.8이상으로 분석되었다(p<0.005). 이는 비점오염저감시설에 적용된 식생, 미생물, 여재 등을 통하여 물리학적 및 생태학적 처리를 통해 저감되기 때문으로 판단된다. 하지만, TN은 인위적 요인과 자연적 요인이 복합적으로 작용으로 배출 특성으로 상관성은 매우 낮은 것으로 분석되었다.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1087-1093
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• 2010

Autotrophic denitrification is known as an effective and economical alternative for heterotrophic denitrification using external carbon sources such as methanol. In this study, we evaluated design and operation parameters for a sulfur denitrification reactor (SDR) treating high strength nitrogen wastewater. The SDR was filled with spherical sulfur media in connected to a pilot-scale nutrient removal process (daily flow rate, $Q=18\;m^3/d$) using moving spongy media. Total nitrogen (TN) concentration of the final effluent was below the 7.0 mg TN/L because nitrate was additionally removed through autotrophic denitrificationin without adding alkalinity (initial alkalinity was $169.4{\pm}20.8\;mg$ $CaCO_3$/L). During the test period, 60~80% of nitrogen in the influent was removed even in low temperature (below $15^{\circ}C$). The alkalinity consumption for nitrate removal in SDR was $4.09{\pm}1.29$ g $CaCO_3/g$ ${NO_3}^-$-N, and the residual alkalinity of influent of SDR was higher than that of theoretical requirements for full conversion of nitrate. The consumption of sulfur was 943.8 g S/d and it was 2.4 times higher than theoretical value (400.1 g S/d) due to abrasion and loss of sulfur media in backwash, etc.

• Proceedings of the Korean Sanitation Conference
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• 2005.12a
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• pp.76-97
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• 2005

As the recent change of multiformity and taste in clination in eating habit culture is yearly in creasing foods used oil and fats. Because the frying food is especially important snack , it's safty is very essential. In order to know the safty and harmfulness of frying oil and fats. The 20 kinds samples were purchased chicken fried food shops around the north of seoul and kyunggi. The acid value, iodine value, peroxide value, TBA value, fatty acid, carbonyl value, and smoke point of deep fat fried oils were analyzed. Results of analyzed, A company of deep fat frying oil showed stability state and C company and B company of deep fat frying oil is acidification to turned. But D company of deep fat frying oil showed quite a bit acidification progressived of used hydrogenated oil.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.3
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• pp.117-125
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• 2002

This study experimented a possibility of advanced treatment through microorganism that converts $NH_3-N$ to organic nitrogen in wastewater contaminated by ammoniac nitrogen unlike conventional nitrogen removal process. After distributing three kinds of special bacteria that use $NH_3-N$ as a substrate, when those bacteria were cultured in no salt condition and salt condition (3% NaCl), M11 showed better growth in salt condition and M12 showed better growth in no salt condition. However M7l grew well in both no salt condition and salt condition. In the test of glucose effect, maximum growth and removal rate were observed in glucose concentration of 5g/L but in high concentration (1000mg/L as $NH_3-N$) of $NH_3-N$ growth and removal rate were low. Removal rate was the highest in 100mg/L $NH_3-N$ and the fact that concentration of $NO_2-N$ and $NO_3-N$ didn't increase assumed $NH_3-N$ was converted to organic nitrogen. Optimum concentration of $K_2HPO_4$ for phosphorous supply and buffer was 5g/L. Special bacteria distributed could use $NO_2-N$ and $NO_3-N$ as well as $NH_3-N$ as substrates. This study showed that when growth rate of bacteria was high removal rate also was high. It is possible to apply as a method to treat wastewater polluted by $NH_3-N$.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.4
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• pp.221-226
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• 1973

In order to investigate the silica effect of insufficient wollastonite to the official standard (above than 15% of suluble silica (N/2 HCl) on rice plant as silica fertilizer, 9 kinds of wollastonites and slag were adopted to examine the amount of silica absorbed by rice straw during growing period, and soluble silica of wollastonites extracted by 7 buffer solutions were compared with silica content in rice straw. Crystalls of ingredient in wollastonite ores were identified by X-ray diffractometer. The results were that silica content of rice plant at growing stages were increased as same ratio of soluble silica. content in wollastonite. Wollastonite containing more than 10% of souble silica (N/2 HCl) could be applied as fertilizer because absorbed amount of silica by rice plant from them are higher than from slag which contained 30% of soluble silica. Wollastonite powder mixed with impure ores in which soluble silica could not be extracted had the same effect on silica absorption of straw as wollastonite powder which contained conformable amount of soluble silica. The soluble silica of wollastonite extracted by buffer solutions (2% citric acid, N. NaOAc, N. $NH_4OAc$, Petermann solution, 0.1M. EDTA, and Hot water) had high significant relation to silica content in rice straw, but soluble silica extracted N/2 hydrochloric acid solutilon, also, had deep relation to them in rice straw. The adequate solution to extract silica from wollastonites is N/2 hydrochloric acid solution because its extracted silia amount is much higher than other solution (about one hundred times) and can be determined by gravimetric analysis. X-ray diffraction pattern would identify qualitatively purity of wollastonite, and large amount of soluble silica was extracted from wollastonite which was appeared to be weathered.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.3
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• pp.43-53
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• 2003

Unlike in analog display devices, the physical screen resolution in digital devices are fixed from the manufacturing. It is a weak point on digital devices. The screen resolution displayed in digital display devices is varied. Thus, interpolation or decimation of the resolution on the display is needed to make the input pixels equal to the screen resolution., This process is called image scaling. Many researches have been developed to reduce the hardware cost and distortion of the image of image scaling algorithm. In this paper, we proposed a Winscale algorithm. which modifies the scale up/down in continuous domain to the scale up/down in discrete domain. Thus, the algorithm is suitable to digital display devices. Hardware implementation of the image scaler is performed using Verilog XL and chip is fabricated in a 0.5${\mu}{\textrm}{m}$ Samsung SOG technology. The hardware costs as well as the scalabilities are compared with the conventional image scaling algorithms that are used in other software. This Winscale algorithm is proved more scalable than other image-scaling algorithm, which has similar H/W cost. This image-scaling algorithm can be used in various digital display devices that need image scaling process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.791-798
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• 1998

To develop natural flavoring substances. optimal hydrolysis conditions for two stage enzyme hydrolysates (TSEH) using low-utilized shellfishes such as purplish clam and frozen oyster stored at $-20^{\circ}C$ for 60 days. The optimal conditions for TSEH method were revealed in temperature at $50^{\circ}C$ 3 hours digestion with alcalase (Aroase AP-10, $0.3%$ w/v, pH 8.0) at the 1st stage and $45^{\circ}C$ 2 hours digestion with neutrase (Pandidase NP-2, $0.3\%$ w/v, pH 6.0) at the 2nd stage. Among water extracts, autolytic extracts and 4 kinds of enzyme hydrolysates tests, TSEH method was superior to other methods on the aspect of yields, nitrogen contents, taste such as umami and control of off-flayer formation, and transparency of extracts. From the results of chemical experiments and sensory evaluation, we may conclude that TSEH from low-utilized marine products is more flavorable compared the conventional enzyme hydrolysates, it could be commercialized as the seasoning substances.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.797-806
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• 2000

The objectives were to compare the biodegradable threshold concentrations of phenol with the different composition of the influent carbon source and examine the SMA (Specific Methanogenic Activity)and the possibility of simultaneous removal of high-strength organics and nitrogen compounds in UASB(Upflow Anaerobic Sludge Blanket) - PBR(Packed Bed Reactor) process. The results showed that UASB reactors were efficient to remove phenol and phenol + glucose from synthetic wastewater. At phenol conc, of 600 mg/L and SCOD conc. of 2100 mg/L in UASB reactor(with only phenol as substrate), the removal efficiencies of phenol and SCOD were over 99% and 93% respectively, under MLVSS of 20 g. The activity of microorganism was $0.112g\;phenol/g\;VSS{\cdot}d$, $0.351g\;SCOD/g\;VSS{\cdot}d$. The gas production rate was $0.115L/g\;VSS{\cdot}d$ and $CH_4$ content in gas was about 70%. At phenol conc. of 760 mg/L and SCOD conc. of 4300 mg/L in UASB reactor( with phenol + glucose as substrates), the removal efficiencies of phenol and of SCOD were over 99% and 90% respectively, under MLVSS of 20 g. The activity of microoganism was $0.135g\;phenol/g\;VSS{\cdot}d$, $0.696g\;SCOD/g\;VSS{\cdot}d$. The gas production rate was $0.257L/g\;VSS{\cdot}d$ and $CH_4$ content in gas was about 70%. Serum bottle test showed that the activity of granule was inhibited over 1600 mg/L phenol conc, and denitrification and methanogenesis simultaneously took place in UASB granules under co-substrates conditions. PBR reactor packed with cilium type media, was efficient in nitrification. In condition of $0.038kg\;NH_4-N/m^3-media{\cdot}d$. 10~12 mg/L phenol conc. and 200~500 mg/L SCOD conc., nitrification efficiency was over 90% and phenol removal efficiency was over 98%.