Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×102 mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

There has been an accelerating increase in water reuse due to growing world population, rapid urbanization, and increasing scarcity of water resources. However, it is well recognized that water reuse practice is associated with many human health and ecological risks due to numerous chemicals and pathogenic microorganisms. Especially, the potential transmission of infectious disease by hundreds of pathogenic viruses in wastewater is one of the most serious human health risks associated with water reuse. In this study, we determined the response of different bacteriophages representing various bacteriophage groups to chlorination in real wastewater in order to identify a more reliable bacteriophage indicator system for chlorination in wastewater. Different bacteriophages were spiked into secondary effluents from wastewater plants from three different geographic areas, and then subjected to various doses of free chlorine and contact time at 5˚C in a bench-scale batch disinfection system. The inactivation of φX174 was relatively rapid and reached ∼4 log10 with a CT value of 5 mg/L*min. On the other hand, the inactivation of bacteriophage PRD1 and MS2 were much slower than the one for φX174 and only ~1 log10 inactivation was achieved by a CT value of 10 mg/L*min. Overall, the results of this study suggest that bacteriophage both MS2 and PRD1 could be a reliable indicator for human pathogenic viruses for chlorination in wastewater treatment processes and water reuse practice.

총호기성균, 대장균군, Escherichia coli, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, Bacillus cereus를 대상으로 충청남도 청양의 맥문동 재배 농가 3곳의 미생물 오염도 조사하였다. 그결과 E. coli O157:H7, L. monocytogenes, Salmonella spp. 는 전혀 검출되지 않았으며, S. aureus는 작업자가 착용한 장갑의 일부에서만 정성적으로 검출되었다. 수확한 맥문동과 접촉가능성이 있는 주변환경(토양, 수확기, 수확용기, 세척기, 세척수, 채반 등)의 미생물 오염도가 전반적으로 낮은 것으로 조사되었는데, 다만 일부 세척기에서 대장균군이 4.35 log CFU/100 cm² 검출되어 위생관리에 유의할 필요가 있는 것으로 나타났다. 맥문동은 수확 이후에 세척과정과 건조 과정을 거치면서 미생물 오염도(총호기성균, 대장균군, B. cereus)가 감소하는 것으로 나타났다.

Temperature correction trans-membrane pressure (TC-TMP) is frequently used as a fouling index in membrane water treatment plants. TC-TMP equation is derived based on an assumption that the total membrane resistance (i.e. the sum of the intrinsic membrane resistance and fouling resistance) is not affected by temperature. This work verified the validity of this assumption using microfiltration (MF) and ultrafiltration (UF) membranes with and without fouling. The foulants used in the work were kaolin (inorganic) and humic acid (organic). The intrinsic resistances of MF and UF membranes remains at constant values regardless of temperature change. When the same amount of foulants were accumulated on the membrane, inorganic fouling resistance with kaolin was constant regardless of temperature change while organic fouling resistance with humic acid decreased at higher temperatures, which means that TC-TMP cannot be used as a fouling index when organic fouling occurs in a real field application. Since TC-TMP underestimates the amount of fouling at higher temperatures, more attention should be necessary in the operation of membrane water treatment plant in a hotter season like summer.

Evaluation and comparison for the performance on the contracting-out became possible after the introduction of the performance indicators(PIs) in 2012 in Korea, And local governments and private companies are utilizing them as evaluation data to enhance the performance of the contracting-out. Several revisions on performance indicator were carried out by expert group on contents validity of PIs, But the review of the composition validity of PIs was not sufficient. In this study, the applicability, distinction ability and composition validity of PIs is evaluated by statistical method. From the results, Improvement of indicator is required in order to increase the interrelationship among indicators to enhance the compostion validity of indicators related with operation, sludge and water reuse

본 연구는 미나리 수확 후 처리환경의 미생물학적 위해 요소를 조사하기 위해 4개 지역의 미나리 재배농가 9곳을 선정하였다. 미나리 재배농가로부터 다양한 시료를 채취 하여 위생지표세균과 병원성 미생물(Escherichia coli O157: H7, Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus)에 대한 오염도를 조사하였다. 먼저, 9개 농가의 재배환경의 미생물 오염도를 분석한 결과 총 호기성 세균과 대장균군이 각각 0~7.00, 0~4.25 log CFU/g, mL, or 100 cm2 수준으로 검출되었다. 대장균(E. coli)은 몇몇 농가의 토양, 관개용수, 세척수 및 작업자의 손에서 양성 반응을 확인하였으며, 양성반응이 관찰된 농가의 경우 작물인 미나리에서도 양성반응을 보였다. 병원성 미생물 중 B. cereus는 토양에서 가장 많이 검출되었으며, 한 농가의 미나리를 제외한 모든 농가의 세척 후 미나리에서 평균 1.2 log CFU/g수준으로 검출되었다. 황색포도상구균은 세척 후 미나리에서 한 건 정성적으로 검출되었으며, 이외에 다른 병원성 미생물은 관찰되지 않았다. 미나리의 경우 손질 및 세척 후에도 오염도가 유사하거나 오히려 다소 증가하는 경향을 보였다. 이상의 결과 미나리 생산농가의 수확 후 처리 시설 및 작업자에 의해 미생물의 교차 오염 가능성이 있으므로 이에 대한 위생관리를 철저히 해야 한다. 또한, 안전성이 확보된 미나리 생산을 위해서는 GAP와 같은 관리제도의 적용이 필요하다.

This study introduces the web-camera image processing-based natural landmark extraction method for automatic welding using 3-axis stage. The welding is a highly significant process in the industries of shipbuilding, automobile, construction, machinery, and so on. However, it has been avoided due to poor working conditions such as fume, spatter, noise, and so on. For the automatic welding system, the web-camera is used to extract the natural landmarks which can give the relative coordinate to set up the initial position of the stage for the welding process. The Canny edge and Hough transformation have been used to extract the significant points for the natural landmark extraction in this paper.

작물의 묘소질은 정식 후 본포에서의 생육이나 수량, 품질에 영향을 미치기 때문에 작물 재배에서 있어서 육묘는 매우 중요하다. 본 연구는 차광을 이용한 다양한 광 수준이 토마토묘와 수박 접목묘의 생육에 어떠한 영향을 미치는지 살펴보고 차광에 의해 변화된 초장, 건물중, 경경 등의 건묘를 나타내는 중요 생육지표간의 상관관계를 분석하여 그동안 사용된 건묘를 판단하는 지표에 대해 검토하기 위해 수행하였다. 차광은 PE 비닐을 이용하여 하루 중 누적광량을 25, 50, 75%를 감소시켰다. 50% 이상 차광할 경우 누적광량에 비하여 토마토묘와 수박 접목묘의 엽면적이 크게 증가하였고 엽면적 지수가 빠르게 증가하였다. 건물중은 차광수준에 따라 감소하는 것으로 나타났다. 누적광량에 따른 토마토묘와 수박 접목묘의 생육은 무차광에 비하여 차광처리에서 빠르게 증가하였다. 토마토묘와 수박 접목묘의 경경은 차광 처리간의 큰 차이를 보이지 않았다. 토마토묘의 경우 단순히 초장과 건물중과의 상관관계가 높았지만 수박 접목묘의 경경은 초장과 상관관계가 없는 것으로 나타났다. 토마토묘의 경경은 묘소질을 판단하기에는 부적절하지만 수박 접목묘의 경우 초장과 함께 경경은 묘소질 판단하는데 이용 가능할 것으로 판단된다.

Background : Angelica gigas is a perennial herb belonging to the family Umbelliferae. Its roots have been utilized as a traditional medicine. The aim of this study is to increase the yield and two indicator components (decursin and decursinol angelate) of Angelica gigas. Methods and Results : The roots of A. gigas were harvested 4 times from early September to late October. Two elicitors (micro element, plant hormone) were treated 4 times at intervals of 2 weeks. The two indicator components were analyzed by HPLC. HM treatment group showed the greatest increase in underground part yield and root diameter. The content of two indicator components in underground part were highest in control (non-treatment) group, but the content of elicitor treatment groups were higher in the aerial part. In the ground part of indicator components content tended to decrease in the elicitor treatment groups, but that groups exceeded the total content of indicator components level of 6% set by the Korean Pharmacopoeia. Conclusion : The highest underground part yield was found in HM treatment group. The highest decursin and decursinol angelate were found in control group. This study provides the basic information for improvement to yield of A. gigas.

This study proposes a selection method of a performance evaluation index of waterproofing and anti corrosion materials used in domestic water treatment facilities for material and construction failures based on different usage and environmental conditions to study the possibility of structural performance maintenance. Different types of waterproofing･anti-corrosion materials have been evaluated based on their respective properties, and have been classified into separate categories based on their case studies of material failures in construction. As a result, 12 different performance evaluation indexes have been produced for the performance evaluation method. Among the 12 performance evaluation index 5 were selected with relatively low importance that produced a low value of 60% importance using AHP analysis method, and conclusively proposed 7 performance evaluation index criteria (wet surface adhesion, fatigue resistance, crack resistance, adhesion performance, joint performance, impact resistance, impermeability)