• 한국환경보건학회지
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• 제30권1호
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• pp.7-14
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• 2004

The change in filamentous bacteria appearance was observed by adjusting factors such as organic and nurient concentration of feed wastewater and the aeration rate in the reactor. In case that COD:N:P and DO were 100:10:1 and 6.1 m1/1 respectively, the mean SVI was 122 ml/g and the filaments were developed normally in flocs. For the low DO con- dition, however, the SVI averaged 186 ml/g and the appearance of outgrowing filaments were more frequent. When the high organic was supplied into the reactor, the average SVI was 274 ml/g and the distinct filamentous bulking was observed. Meanwhile when COD:N:P was maintained at 100: 1 :0.5, the SVI was as low as 87 ml/g and the appearance of filaments were minimal and the size of flocs was small comparing other experimental conditions. For normal, low aeration and high organic concentration, predominant filaments in the early stage of experiments were commonly Type 021N,S. natans which were usually found in low DO condition. However, Type 041, Type 1851, Type 0961 became predominant as experiments extended. Meanwhile, in low nutrient condition, Type 0675, Type 1851, and Type 0961 were observed. The filamentous bacteria appearance for SVI< 150(ml/g), Type 0041, Type 0961 (usually low organic in feed wastewater) were predominantly observed and SVI > 150(ml/g), S. natans and Type 021N(usually low DO in aeration basin) was predominant.

• 혜화의학회지
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• 제14권2호
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• pp.177-187
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• 2005

Objective : This study is designed in order to evaluate the therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) on acute low back pain Methods : We investigated 10 patients suffering from acute low back pain were treated from Mach. 1st 2005 to Jun. 30th 2005. 10 patients, were diagnosed only straightened curvature on lateral view of lumbar spine X-ray and get Scalp acupunture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) and Do-ma acupuncture. Pain rating score(PRS) was used to assess the pain for its intensity, frequency, duration, and aggravating factors. And visual analog scale(VAS) was used, too. Results : Both Scalp acupunture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) and Do-ma acupuncture therapy showed good effect on acute low back pain. It was proved by the difference between PRS and VAS checked before treatment and what checked after treatment. In the evaluation of treatment effect, Exellent was 2(20%), Good was 5(50%), Moderate was 3(30%), Poor was 0(0%). Conclusion : The therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture on acute low back pain can be recommended as a useful therapy to treat acute low back pain.

• 한국환경보건학회지
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• 제9권1호
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• pp.1-13
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• 1983

This study was carried out to investigate nitrification in the main stream of the Naktong river for two times, 12-13 August and 23-26 September 1982. The results of this study were as follows : 1. The increase of nitrogen concentration was due to inflow of Geumho river, which was polluted by the municipal and industrial wastewater of Daegu city. 2. The rate constant of ammonia calculated for three reaches was high according to the stream flow and was eminently low in the reach from Goroung to Gangjung. (0.068-0.116 $day^{-1}$). This phenomena might be attributed to the sublethal or even lethal effect upon aquatic life by relatively low DO concentration and high heavy metal concentration. 3. DO consumption rate by nitrification was highest for the reach from Goroung to Daeam where was affected by Geumho river. (56.7-147.8%). This phenomena might be attributed to low DO concentration and high nitrogen concentration. Especially, the less stream flow was, the higher DO consumption was. And so, nitrification in the station where is low DO concentration, especially under the low flow condition, might cause more serious water quality management problem. Therefore, for the purpose of effective conservation of water quality in the Naktong river, it was suggested that We have more concern about the nitrogen compound, and more study on the nitrification phenomena.

• 상하수도학회지
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• 제33권3호
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• pp.215-224
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• 2019

Recent focus on wastewater treatment includes energy-saving and renewable energy generation for energy-independence of water infrastructures. Aeration and pumping in biological wastewater removal processes account for nearly 30-60% of the total electricity cost in real wastewater treatment plants. In this study, the performance and microbial characteristics were investigated in sequencing batch reactor under typical oxygen and oxygen limited condition. Under typical DO ($7.55{\pm}0.99mg/L$) and low DO ($0.23{\pm}0.08mg/L$) conditions, COD removal was stable over 91 % during SBR operation. Ammonia removal efficiency was reduced from 95.6 % to 89.2 % when DO concentration was dropped sharply. Phosphorus removal efficiency also reached 77% at oxygen-limited condition. The results indicated that removal efficiency both ammonia and phosphorus was influenced by DO condition. Microbial analysis revealed that Proteobacteria and Bacteroidetes at phylum level was dominant in typical DO and low DO conditions and DO concentration did not much affect phylum distribution. Population decrease of genera of nitrifying bacteria(Dokdonella) and Dechloromonas spp. affect removal efficiency of nitrogen and phosphorus at low DO condition.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2020년도 춘계학술대회
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• pp.197-197
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• 2020

• E2M - 전기 전자와 첨단 소재
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• 제8권3호
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• pp.254-260
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• 1995

A method is described for the design and fabrication of the sensor interface circuits on the Clark electrodes for the dissolved oxygen(DO). The discussion includes a method for the +5 V single-supply driving for the sensor circuits, which has low power comsumption for the front-end electronics. DO probe under test is composed of the Clark electrode with silver anode, gold cathode and the electrolyte of half saturated KCI solution and the FEP teflon memtrance for the oxygen penetration. Typical polarograms for the DO probes by using this sensor circuit reveals high accuracy over 99% of the I to V conversion. Partial pressure of oxygen obtained from the polarograms are well suited to the results calculated. It is expected that the proposed sensor circuits can be utilized into the customized IC for the battery-driven small-size DO meters.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권5호
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• pp.2651-2673
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• 2019

In order to detect Denial of Service (DoS) attacks, victim-side detection methods are used popularly such as static threshold-based method and machine learning-based method. However, as DoS attacking methods become more sophisticated, these methods reveal some natural disadvantages such as the late detection and the difficulty of tracing back attackers. Recently, in order to mitigate these drawbacks, source-side DoS detection methods have been researched. But, the source-side DoS detection methods have limitations if the volume of attack traffic is relatively very small and it is blended into legitimate traffic. Especially, with the subtle attack traffic, DoS detection methods may suffer from high false positive, considering legitimate traffic as attack traffic. In this paper, we propose an effective source-side DoS detection method with traffic seasonality aware adaptive threshold. The threshold of detecting DoS attack is adjusted adaptively to the fluctuated legitimate traffic in order to detect subtle attack traffic. Moreover, by understanding the seasonality of legitimate traffic, the threshold can be updated more carefully even though subtle attack happens and it helps to achieve low false positive. The extensive evaluation with the real traffic logs presents that the proposed method achieves very high detection rate over 90% with low false positive rate down to 5%.

• 한국응용곤충학회지
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• 제52권3호
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• pp.161-169
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• 2013

본 실험은 오이재배시 사용되는 살충제 47종이 진딧물 포식성 천적인 진디혹파리(Aphidoletes aphidimyza Rondani)의 모든 발육단계에 얼마나 영향을 주는가를 평가하였다. 진디혹파리 알에 대한 살충제의 독성평가 결과 emamectin benzoate 등 22종의 살충제가 낮은 독성을 보였다. 알에 독성이 낮은 22종 살충제 중 flonicamid를 포함하는 12종 살충제가 진디혹파리 유충에 대하여 0~27%로 낮은 독성을 보였으나, indoxacarb + teflubenzuron와 chlorantraniliprole의 독성은 각각 35.4%와 64.6%였다. 진디혹파리 유충에 보통독성 이하의 독성을 보인 indoxacarb + teflubenzuron와 chlorantraniliprole을 포함한 14종 살충제는 진디혹파리의 번데기와 성충에도 낮은 독성을 보였다.

• 전자공학회논문지T
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• 제35T권1호
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• pp.29-32
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• 1998

실리콘 산화막에서 저레벨 누설전류를 조사하였다. 저레벨 누설전류는 전이요소와 직류요소로 구성되어 있다. 전이요소는 스트레스에 의해 두 계면트랩 가까이 발생된 트랩의 충방전에 의한 터널링으로 나타났으며 직류요소는 산화막을 통한 트랩 어시스트 터널링으로 나타났다 그리고 저레벨 누설전류는 산화막에서 발생된 트랩의 수에 비례하였다. 저레벨 누설전류는 트랩의 충방전 누설전류이며 비휘발성 소자의 데이터 유지능력에 영향을 주었다.

• Journal of Acupuncture Research
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• 제23권3호
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• pp.207-214
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• 2006

Objectives : This study is designed in order to evaluate the therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) on acute low back pain Methods : We investigated 30 patients suffering from acute low back pain were admitted to Dunsan O.M.hospital from March. 1st 2005 to December. 30th 2005. We divided into two groups: one group was treated with Scalp acupunture, another group was treated with common acupuncture. 30 patients, were diagnosed only straightened curvature on lateral view of lumbar spine X -ray. Scalp acupunture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) and Do-ma acupuncture. To estimate the efficacy of treatment that applied for two groups, we compared the visual analog scale(VAS), Oswestry disabiliby index(ODI) and Straight Leg Raising Test(SLRT) score of two groups statistically. Results : Both Scalp acupuncture related with Governer Vessel(Dok) and Bladder Meridian (Chok-taeyang) and Do-ma acupuncture therapy showed good effect on acute low back pain. It was proved by the difference between VAS, ODI and SLRT score checked before treatment and what checked after treatment on each groups. Conclusion: The therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture on acute low back pain can be recommended as a useful therapy to treat acute low back pain.