• 한국물환경학회지
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• 제26권6호
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• pp.1028-1033
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• 2010

Wastewater reuse for agricultural irrigation needs treatment and control of pathogens to minimize risks to human health and the environment. In order to evaluate the water quality of UV-treated reclaimed water, this study focused on the relationship between micro-pathogens and particulate matters. MS2 was selected as an index organism because it has similar characteristics to human enteric virus and strong resistance to UV disinfection. The turbidity and suspended solid (SS) were selected for test parameters. In this study, it was performed with different UV doses (30 and $60mJ/cm^2$) for estimation of the MS2 inactivation rate using collimated beam batch experiments in the laboratory. The experiment results by turbidity or SS concentration presented that the increased concentration of them lowered MS2 inactivation. At the turbidity (below 4.27 NTU) and SS (below 1.47 mg/L) of the low level range, the inactivation of 60 UV dose is higher than 30 UV dose. However, at the turbidity and SS of the high level, the increasing UV dose did not show apparent increasing the MS2 inactivation. In quantitative microbial risk assessment (QMRA), it can confirm the trend that $P_D$ and turbidity concentrations have positive correlationship at the low concentration, which was also observed in SS. The QMRA can be helpful in communication with public for safe wastewater reuse and be recommended.

• 한국산학기술학회논문지
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• 제11권9호
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• pp.3375-3379
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• 2010

본 논문은 89명의 여대생을 대상으로 아유르베다의 세 가지 체질인 바타, 피타, 카파에 따른 얼굴 피부의 수분, 유분, pH의 값을 측정하여 비교하였다. 아유르베다 체질에 따른 피부 상태를 알아보기 위하여 분석한 결과 수분의 경우 피타, 카파, 바타의 순으로(p<0.001) 유분의 경우 카파, 피타, 바타의 순으로 (p<0.001, p<0.01) pH의 경우 카파, 피타, 바타의 순으로 (p<0.01) 통계적으로 유의한 차이가 있었다. 앞으로의 연구에서는 피부미용학적 관점에서 아유르베다 체질에 대한 보다 체계적이고 과학적인 연구가 진행되어야 할 것이다.

• 한국기계가공학회지
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• 제17권3호
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• pp.87-92
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• 2018

As gas turbines for power generation become increasingly more important for high capacity and high efficiency, the technological development and investment of companies are increasing globally. Gas turbine manufacturing technology is only owned by a few companies such as GE, Siemens, and MHI, and our country currently depends on imports of processing technology and component parts. The core part of the gas turbine is curvic coupling tooth processing technology that improves turbine efficiency by smoothly transmitting power to the turbine rotor. Curvic coupling tooth machining and evaluation research is restricted overseas, and it is not underway in Korea. Therefore, in this study, roughing and finishing process technology for curvic coupling tooth machining is developed and a quantitative evaluation method is proposed. For the development of machining technology, the analysis of critical parameters was performed through C & E analysis. In the roughing process, the conditions considering the minimum machining time and tool load ratio were determined. Finishing process conditions were determined based on the contact ratio between the tooth surfaces. The image-processing method is presented for evaluation of the contact ratio and a verification test was performed.

• 한국의류학회지
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• 제38권4호
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• pp.440-454
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• 2014

This study examined the wearing effect of 3D compression suits on quantitative electroencephalogram (EEG) during walking and rest. Ten males in their 20s wore three types of experimental clothing, a loose-fit wear (BS), a 3D compression suit (3D CS), and a power film welded on CS (3D WCS); in addition, EEG signals were measured during resting, walking, after walking, and after sit-ups. The results showed that a higher pressure (due to 3D CS and 3D WCS) increased the 'Concentration' level and the 'Cognitive load' of brain waves during treadmill walking due to a higher cortex activity level when walking. Differentiation was shown between two compression suits and BS was enhanced during walking on a treadmill; however, the brain waves of 'Relaxation' between two compression suits were significantly different after walking, i.e., 'Relaxation' level of 3D WCS was the highest. Rigorous exercise such as sit-ups was inefficient to distinguish the effect of compression suits on EEG. Participants perceived a higher pressure due to compression suits; however, the wear comfort of two compression suits was maintained. Two compression suits were rated as supportive and helpful during walking. Various EEG parameters such as the indices of 'Relaxation', 'Concentration' and 'Cognitive load' were effective to observe the effect of 3D compression suits on wearers' brain waves during and after walking.

• 한국미생물·생명공학회지
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• 제31권3호
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• pp.264-270
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• 2003

1.북부 하수처리장에서 동정된 원생동물 및 후생동물의 종류는 32속으로 섬모충류는 17속이었다. 총 개체수는 연평균 5,266개체/ml(2,631∼9,744)이며, 속별 개체수는 Trachelophyllum이 가장 많았다. 종류별로는 편모충류가 6속(11%), 육질충류 3속(7%), 섬모충류 17속(78%), 후생동물이 6속(4%)이며, 섬모충류는 나구류와 시모류가 각각 33%, 23%을 차지하였다. 총 개체수는 하절기에 감소하고 동절기에 상승하는 경향을 나타내었다. 2. 수온 $20^{\circ}C$ 미만인 경우, 속별 개체수와 유출수 BOD, SS농도는 음의 상관관계가 형성되고, 속별 개체수와 유출수 COD, TN, TP농도는 양의 상관관계가 형성되었다. 상관분석의 결과 $20^{\circ}C$미만의 자료에서 Lepadella가 TP제거율에 대한 지표 미생물로의 가능성이 나타나며, Trochilia, Entosiphon, Coiepus는 TN제거율의 지표미생물로의 가능성이 추정된다. 3. 수온 $20^{\circ}C$ 이상인 경우, $20^{\circ}C$ 미만인 경우보다 상관계수가 낮았으며, 전반적으로 속별 개체수와 수질 항목이 음의 상관관계를 형성하였다. Entosiphon, Paramecium은 출현빈도는 낮지만 유출수 TP농도와 양의 상관관계를, TP제거율과 음의 상관관계를 형성함으로 이들 원생동물속의 개체수 증가시에는 유출수 TP가 악화된다는 점에 주의하면서 운전하여야 한다.

• Applied Biological Chemistry
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• 제37권6호
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• pp.516-521
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• 1994

새로운 17종의 imazapyr 유도체인 3-(N-methyl-N(X)-치환-phenylaminooxoacetyl)-2-(4-isopropyl-5-oxo-2-imidazoline-2-yl)pyridine, 6을 합성하고 3-(N-methyl-N(X)-치환-phenylaminooxoacetyl group중의 X-치환기 변화에 따른 구조와 옥수수(Zea mays L.)와 참비듬(Amaranthus viridis L.)에 대한 발아 전의 제초활성에 미치는 관계(SAR)를 검토 한 바, 옥수수의 경우에는 MR상수의 적정값(optimal value)이 $5.56\;cm^3/mol$이었으므로 이 값보다 크거나 작을수록 제초활성이 작았다. 참비듬의 경우에는 $L_1$상수의 적정값이 3.34 A이므로 이 값에 가까울수록 제초활성이 클 것임을 알 수 있었다. 특히, 2,5-difluoro group 치환체, 6i는 참비듬에 가장 큰 제초활성을 나타내었으나 옥수수에는 가장 작은 제초활성을 미치므로써 현저하게 두 초종간에 선택성을 나타내는 화합물이었다.

• 지질공학
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• 제28권3호
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• pp.455-463
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• 2018

본 연구에서는 치핑작업중에 콘크리트에 발생할 수 있는 손상균열을 정량분석하기 위해 X-ray CT 이미지를 이용하는 방법을 제안하고자 한다. 이를 위해 치핑작업을 수행한 후, 균열이 발생한 콘크리트 블록을 코어링하여 직경 50 mm, 길이 100 mm의 시편을 준비하였다. 그 후 마이크로 포커스 X-ray CT 촬영을 하여 얻은 이미지를 3D 이미지로 재구성(reconstruction)하였다. 이렇게 얻어진 3D CT 이미지에 3DMA (3 Dimensional Medial axis Analysis)법을 적용하여, 손상 평가 파라메타로 시편의 위치에 따라 균열의 성질을 평가하여 손상을 분석하였다. 분석결과 치핑에 의한 손상은 치핑 표면으로부터 3 cm 깊이까지 발생한 것으로 나타났다. 또한 CT이미지 공간분석법에서 사용되는 여러 파라메타 중 공극률 지표(Porosity index), Burn number 그리고 Medial axis 의 파라메타를 이용해 치핑표면 근처의 손상 분석이 가능하다는 것이 확인되었다. 이 방법은 내부구조에 변화가 발생한 암석을 대상으로 한 연구에서도 비파괴 상태로 내부의 균열 평가, 가시화에 적용가능하다.

• Clinical and Experimental Pediatrics
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• 제61권2호
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• pp.43-48
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• 2018

Purpose: Human adenovirus infection mimics Kawasaki disease (KD) but can be detected in KD patients. The aim of this study was to determine the clinical differences between KD with adenovirus infection and only adenoviral infection and to identify biomarkers for prediction of adenovirus-positive KD from isolated adenoviral infection. Methods: A total of 147 patients with isolated adenovirus were identified by quantitative polymerase chain reaction. In addition, 11 patients having KD with adenovirus, who were treated with intravenous immunoglobulin therapy during the acute phase of KD were also evaluated. Results: Compared with the adenoviral infection group, the KD with adenovirus group was significantly associated with frequent lip and tongue changes, skin rash and changes in the extremities. In the laboratory parameters, higher C-reactive protein (CRP) level and presence of hypoalbuminemia and sterile pyuria were significantly associated with the KD group. In the multivariate analysis, lip and tongue changes (odds ratio [OR], 1.416; 95% confidence interval [CI], 1.151-1.741; P=0.001), high CRP level (OR, 1.039; 95% CI 1.743-1.454; P= 0.021) and sterile pyuria (OR 1.052; 95% CI 0.861-1.286; P=0.041) were the significant predictive factors of KD. In addition, the cutoff CRP level related to KD with adenoviral detection was 56 mg/L, with a sensitivity of 81.8% and a specificity of 75.9%. Conclusion: Lip and tongue changes, higher serum CRP level and sterile pyuria were significantly correlated with adenovirus-positive KD.

• 분석과학
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• 제23권1호
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• pp.74-82
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• 2010

휴대형 형광 분석기의 개발을 위한 사전 기초연구로서 탁상형 및 휴대형 X-선 형광분석기를 이용하여 플라스틱 중의 Cd, Pb, Hg, Cr (IV), polybrominated biphenyls (PBB) 및 polybrominated diphenyl ethers (PBDE)의 RoHS 규제 물질에 대하여 비교 분석하였다. 규제 물질이 0~1,200 mg/kg의 농도로 함유된 폴리에틸렌 및 폴리프로필렌 인증표준물질을 사용하여 측정시간에 따른 최적의 분석 조건을 확립하고, 각 규제 물질의 검량곡선을 작성하였다. 플라스틱 인증표준물질과 시료 중의 Pb, Hg, Cd, 총 Cr 및 총 Br 함량을 탁상형 X-선 형광분석기의 empirical (EM) 법 및 fundamental parameter (FP) 법으로 정량분석하고 그 결과를 휴대형 X-선 형광분석기와 비교 하였다.

• Nutrition Research and Practice
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• 제2권3호
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• pp.184-190
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• 2008

The purpose of this study was to compare the dietary habits, nutrient intake, bone mineral density(BMD) and bone metabolism in Korean male collegians as related to smoking situation. One hundred sixty one young adult males at the age of 20-26 participated in this study. The subjects were divided into four groups: non smoker(n=42), light smoker(n=34), moderate smoker(n=49) and heavy smoker(n=36). The anthropometric characteristics, smoking situations, dietary habits and nutrient intakes were observed. Bone status of the calcaneus was measured by using quantitative ultrasound(QUS). Bone metabolism markers including serum alkaline phosphatase activity(ALP) and N-mid osteocalcin(OC) were analyzed. There were no significant differences in height, weight, BMI, energy and calcium intake among the four groups. Iron intake of moderate and heavy smoker was significantly lower than that of light smoker. Heavy smokers consumed significantly lower vitamin C than moderate smokers, and their coffee consumption and lifetime alcohol consumption were significantly highest among the 4 groups. QUS parameters and serum ALP were not significantly different among the four groups. Serum OC levels were significantly lower in heavy and non smoker group compared to the moderate smoker group. In conclusion, heavy smokers in young male collegians had undesirable lifestyle and dietary habits, like as high consumption of coffee and alcohol, and low intake of Fe and vitamin C. Although, there was no significant difference in their current bone status from the other groups, these undesirable factors with heavy smoking may affect their bone health in the long term.