• Title/Summary/Keyword: FNR process

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A Study on Nitrogen and Phosphorus Removal in FNR Process (FNR process를 이용한 하수처리장의 질소.인의 제거에 관한 연구)

  • Cho Il-Hyoung;Lee Nae-Hyun;Lee Seung-Mok;Kim Young-Kyu
    • Journal of Environmental Science International
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    • v.15 no.6
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    • pp.571-577
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    • 2006
  • This study make a comparison between the phosphorus removal performance of FNR(Ferrous Nutrient Removal) process and A/O process by the laboratory experiments. For simultaneous removal of phosphorus, iron electrolysis was combined with oxic tank. Iron precipitation reactor on the electrochemical behaviors of phosphorus in the iron bed. The phosphorus removal in FNR process was more than A/O process. Iron salts produced by iron electrolysis might help to remove COD and nitrogen. And the demanded longer SRT is the more removes the removes COD, nitrogen, and phosphorus. Also, FNR process of sludge quantity more reduce than A/O process to input cohesive agents.

A Study on Phosphorus Removal Effects Per Iron Surface Area in FNR Process (철전기분해장치(FNR)에서 철판의 표면적이 인제거에 미친 영향에 관한 연구)

  • Kim, Young-Gyu
    • Journal of Environmental Health Sciences
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    • v.38 no.6
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    • pp.568-574
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    • 2012
  • Objectives: The purpose of this experiment is to understand the phosphorus removal ratio effects of iron plates per unit of surface area through the iron electrolysis system, which consists of an anoxic basin, aerobic basin, and iron precipitation apparatus. Methods: Iron electrolysis, which uses an iron precipitation reactor in anoxic and oxic basins, consisted of iron plates with total areas of 400 $cm^2$, 300 $cm^2$ and 200 $cm^2$ respectively. The FNR process was operated with a hydraulic retention time and a sludge retention time of 12 hours and three days, respectively. Wastewater used in the experiments was prepared by dissolving $KH_2PO_4$ in influent water. Results: The iron plates 400 $cm^2$ (16.6 $mA/cm^2$), 300 $cm^2$ (13.3 $mA/cm^2$) and 200 $cm^2$ (7.3 $mA/cm^2$) in surface area in the phosphorus reactor had respective phosphorus of 2.4 mg/l, 2.7 mg/l and 3.2 mg/l in the effluent and phosphorus removal respective efficiencies of 90.3%, 89.1% and 87.1%. The effluent in the reactor, where the iron plate was not used, had relatively very low phosphorus removal efficiency showing phosphorus concentration of 15.3 mg/l and a phosphorus removal efficiency about 38.3%. Phosphorus removal per ferrous was 0.472 mgP/mgFe in the iron electrolysis system where the surface area of iron was low. Phosphorus pollution load per active surface area and the phosphorus removal efficiency had an interrelation of RE = -0.27LS + 89.0 (r = 0.85). Conclusion: With larger iron plate surface area, the elution of iron concentration and phosphorus removal efficiency was higher. The removal efficiency of phosphorus has decreased by increasing the initial phosphate concentration in the iron electrodes. This shows a tendency of decreasing phosphorus removal efficiency because of decreasing of iron deposition as the phosphorus pollution load per active surface area increases.

GCNXSS: An Attack Detection Approach for Cross-Site Scripting Based on Graph Convolutional Networks

  • Pan, Hongyu;Fang, Yong;Huang, Cheng;Guo, Wenbo;Wan, Xuelin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.12
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    • pp.4008-4023
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    • 2022
  • Since machine learning was introduced into cross-site scripting (XSS) attack detection, many researchers have conducted related studies and achieved significant results, such as saving time and labor costs by not maintaining a rule database, which is required by traditional XSS attack detection methods. However, this topic came across some problems, such as poor generalization ability, significant false negative rate (FNR) and false positive rate (FPR). Moreover, the automatic clustering property of graph convolutional networks (GCN) has attracted the attention of researchers. In the field of natural language process (NLP), the results of graph embedding based on GCN are automatically clustered in space without any training, which means that text data can be classified just by the embedding process based on GCN. Previously, other methods required training with the help of labeled data after embedding to complete data classification. With the help of the GCN auto-clustering feature and labeled data, this research proposes an approach to detect XSS attacks (called GCNXSS) to mine the dependencies between the units that constitute an XSS payload. First, GCNXSS transforms a URL into a word homogeneous graph based on word co-occurrence relationships. Then, GCNXSS inputs the graph into the GCN model for graph embedding and gets the classification results. Experimental results show that GCNXSS achieved successful results with accuracy, precision, recall, F1-score, FNR, FPR, and predicted time scores of 99.97%, 99.75%, 99.97%, 99.86%, 0.03%, 0.03%, and 0.0461ms. Compared with existing methods, GCNXSS has a lower FNR and FPR with stronger generalization ability.

Characterization of Phosphorus Removal in Wastewater Using Iron Precipitation Reactor (철 석출장치에 의한 폐수 중의 인 제거 특성)

  • Cho Il-Hyoung;Zoh Kyung-Duk;An Sang-Woo;Chang Soon-Woong;Kim Young-Kyu
    • Journal of Environmental Health Sciences
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    • v.32 no.1 s.88
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    • pp.89-95
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    • 2006
  • This study was conducted to improve an effect of phosphorus removal using FNR(Ferrous Nutrient Removal) process which had iron precipitation reactor and to analyze the iron corrosion. For simultaneous removal of phosphorus, iron electrolysis was combined with oxic tank. In this study, The removal efficiency of phosphorus increased with an increase voltage in iron precipitation reactor. The distance of 15mm between the two iron bed in each tests influence the concentration of remaining phosphorus most. The extensive surface area of iron bed is the more removes the phosphorus. In this test the $400\;cm^2$ of surface area was proved to be the most removal efficient.

Design of Optimal Water Treatment Processes based on Required Water Quality for Utilization of the Saemanguem Lake Water (새만금 담수 활용을 위한 요구수질별 최적의 수처리 방안 연구)

  • Choi, Kyung-Sook;Lee, Kwang-Ya
    • Journal of agriculture & life science
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    • v.46 no.2
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    • pp.169-178
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    • 2012
  • This study was aimed at providing optimal water treatment processes based on various required water quality for utilization of the Saemangeum lake water as water supply alternatives to this area. Various water treatment methods were considered for investigation there characteristics, pollution removal rate, pros and cons in order to select appropriate water treatment processes satisfying the required water quality for different purposes. As results, the FDA system for SS, turbidity, BOD removals, UV treatment for coliform, BOD removals, FNR process for T-N, T-P removals, and ECRS process for desalination purpose were found to be better methods in senses of removal efficiency, operation and maintenance. Case studies were provided with cost analysis for field applications in the Saemangeum area.

Metal pad Discolored Image Classification Algorithm using Geometric Texture Information (기하학적 텍스쳐 정보를 이용한 금속 패드 변색영상 분류 알고리즘)

  • Cui, Xue Nan;Kim, Hak-Il
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.5
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    • pp.469-475
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    • 2010
  • This paper presents a method of classifying discolored defects of metal pads using geometric texture for AFVI (Automated Final Vision Inspection) systems. In PCB manufacturing process, the metal pads on PCB can be oxidized and discolored partly due to various environmental factors. Nowadays the discolored defects are manually detected and rejected from the process. This paper proposes an efficient geometric texture feature, SUTF (Symmetry and Uniformity Texture Feature) based on the symmetric and uniform textural characteristics of the surface of circular metal pads for automating AFVI systems. In practical experiments with real samples acquired from a production line, 30 discolored images and 1232 roughness images are tested. The experimental results demonstrate that the proposed method using SUTFs provides better performance compared to Gabor feature with 0% FNR (False Negative Rate) and 1.46% FPR (False Positive Rate). The performance of the proposed method shows its applicability in the real manufacturing systems.

A Study on Phosphorus and Nitrogen Removal with Unit Operation in the Ferrous Nutrient Removal Process (철전기분해장치(FNR)에서 단위공정에 따른 질소와 인의 제거)

  • Kim, Soo Bok;Kim, Young-Gyu
    • Journal of Environmental Health Sciences
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    • v.39 no.1
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    • pp.83-89
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    • 2013
  • Objectives: The purpose of this experiment was to illuminate the relationship between the phosphorus removal rate of unit operation and the phosphorus removal rate of phosphorus volume loading in the Ferrous Nutrient Removal process, which consists of an anoxic basin, oxic basin, and iron precipitation apparatus. Methods: This study was conducted in order to improve the effect of nitrogen and phosphorus removal in domestic wastewater using the FNR (Ferrous Nutrient Removal) process which features an iron precipitation reactor in anoxic and oxic basins. The average concentration of TN and TP was analyzed in a pilot plant ($50m^3/day$). Results: The removal rate of T-N and T-P were 66.5% and 92.8%, respectively. The $NH_3-N$ concentration of effluent was 2.62 mg/l with nitrification in the oxic basin even though the influent was 17.7 mg/l. The $NO_3$-N concentration of effluent was 5.83 mg/l through nitrification in oxic basin even though the influent and anoxic basin were 0.82 mg/l and 1.00 mg/l, respectively. The specific nitrification of the oxic basin ($mg.NH_3$-Nremoved/gMLVSSd) was 16.5 and specific de-nitrification ($mg.NO_3$-Nremoved/gMLVSSd) was 90.8. The T-P removal rate was higher in the oxic basin as T-P of influent was consumed at a rate of 56.3% in the anoxic basin but at 90.3% in the oxic basin. The TP removal rate (mg.TP/g.MLSS.d) ranged from 2.01 to 4.67 (3.06) as the volume loading of T-P was increased, Conclusions: The test results showed that the electrolysis of iron is an effective method of phosphorus removal. Regardless of the temperature and organic matter content of the influent, the quality of phosphorus in the treated water was both relatively stable and high due to the high removal efficiency. Nitrogen removal efficiency was 66.5% because organic matter from the influent serves as a carbon source in the anoxic basin.

Sentinel Node Biopsy Examination for Breast Cancer in a Routine Laboratory Practice: Results of a Pilot Study

  • Khoo, Joon-Joon;Ng, Chen-Siew;Sabaratnam, Subathra;Arulanantham, Sarojah
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1149-1155
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    • 2016
  • Background: Examination of sentinel lymph node (SLN) biopsies provides accurate nodal staging for breast cancer and plays a key role in patient management. Procurement of SLNs and the methods used to process specimens are equally important. Increasing the level of detail in histopathological examination of SLNs increases detection of metastatic tumours but will also increase the burden of busy laboratories and thus may not be carried out routinely. Recommendation of a reasonable standard in SLN examination is required to ensure high sensitivity of results while maintaining a manageable practice workload. Materials and Methods: Twenty-four patients with clinically node-negative breast cancer were recruited. Combined radiotracer and blue dye methods were used for identification of SLNs. The nodes were thinly sliced and embedded. Serial sectioning and immunohistochemical (IHC) staining against AE1/AE3 were performed if initial H&E sections of the blocks were negative. Results: SLNs were successfully identified in all patients. Ten cases had nodal metastases with 7 detected in SLNs and 3 detected only in axillary nodes (false negative rate, FNR=30%). Some 5 out of 7 metastatic lesions in the SLNs (71.4%) were detected in initial sections of the thinly sliced tissue. Serial sectioning detected the remaining two cases with either micrometastases or isolated tumour cells (ITC). Conclusions: Thin slicing of tissue to 3-5mm thickness and serial sectioning improved the detection of micro and macro-metastases but the additional burden of serial sectioning gave low yield of micrometastases or ITC and may not be cost effective. IHC validation did not further increase sensitivity of detection. Therefore its use should only be limited to confirmation of suspicious lesions. False negative cases where SLNs were not involved could be due to skipped metastases to non-sentinel nodes or poor technique during procurement, resulting in missed detection of actual SLNs.

A Study for Visual Style for Feature Animation - A Case of Feature Animation - (극장 판 장편 애니메이션의 시각적 스타일에 관한 연구 -장편애니메이션 'Life is Cool'의 제작사례를 중심으로-)

  • Choi, Seung-Won
    • Journal of Broadcast Engineering
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    • v.12 no.5
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    • pp.391-400
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    • 2007
  • The ways of expression are infinite to make animated film. When we compare to live action film, that fact is the actual power that animation only has and is one of the big weapons to appeal to the audience. Nonetheless, techniques to be chosen are monolithic like drawing, 3D computer, and clay when animation maker makes feature animation to screen in movie theatre. It's probably because feature animation must have popularity of visual style and they need to standardize technique about side of making. But popularity in expression does not mean monolithic visual style and making technique. It should be understood about side of artistic value to fascinate public audience. Audience is always eager for new subject, new directing style and new visual style. Monotonous and boring animation cannot but turn away from the audience. So if production does not have artistic value, we cannot expect commercial value and success also even it plans and makes for the feature animation. To create new visual style fnr animation is not only limited to artwork itself but also creation, which is included story and tone of the film and acting style about character. Also making process must be calculated and experimented to actualize that visual style about side of making.