• 한국수자원학회논문집
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• 제32권3호
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• pp.301-310
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• 1999

본 연구에서는 하천-대수층 계에서 수치모형과 두 종류의 해석모형을 적용하여 유도침투량 곡선을 유도하여 비교하였으며, 투수계수의 이방성비 및 지하수 유입 방향이 유도침투량 산정에 미치는 영향을 평가하였다. 유도침투량 곡선은 단순한 그래프 형태로 표시되며, 유도침투량, 양수량, 하천과 우물사이의 거리, 유동 지하수 유입량 등의 4가지 인자만을 포함하기 때문에 유도침투량의 결정에 유용하게 적용될 수 있다. 검토된 조건 아래에서 Wilson 해석모형과 FEWA 수치모형의 유도침투량 곡선은 근사적으로 일치하였으며, 투수게수의 이방성비는 유도침투량에 큰 영향을 미치는 인자로 평가되었다. 본 연구에서 적용된 방법과 도출된 결과들은 유도침투 현상을 이해하는데 도움이 되며, 양수우물의 계획 및 설계, 용수공급 우물의 수질관리에 필요한 유도침투량과 양수량의 최적 결정에 적용될 수 있다.

• 한국멀티미디어학회논문지
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• 제21권1호
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• pp.34-44
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• 2018

An early detection of intravenous (IV) infiltration is essential to minimize the injuries during infusion therapy, which is one of the most important tasks for nurses in nursing settings. We report that bioelectrical impedance analysis is useful in the early detection of infiltration at puncture sites. When infiltration was intentionally induced in the vein of a pig's posterior ear, impedance parameters (R, $X_C$, $C_m$) showed significant differences before and after infiltration. In particular, the relative resistance ($R/R_{BI}$) decreased significantly at infiltration and then slowly decreased. This indicates that the vein in pig's ear is thin and the amount of surrounding subcutaneous tissue, and hence the infiltrated solution accumulates slowly after infiltration. However, when infiltration was induced in the vein of human's forearm, the relative resistance at 20 kHz decreased gradually over time. In the $R-X_C$ graph, the positions in the case of infiltration induced in the pig' ear shifted rapidly before and after infiltration, whereas the positions in the case of infiltration induced in the human's forearm moved gradually during infiltration. Our findings suggest that the impedance parameters (R, $R/R_{BI}$, $X_C$, R vs. $X_C$, and $C_m$) are effective indicators to detect the infiltration early in a non-invasive and quantitative manners.

• 센서학회지
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• 제26권5호
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• pp.306-313
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• 2017

An early detection of infiltration in veins is essential to minimize the injuries caused during infusion therapy, which is one of the most important tasks for nurses in clinical settings. We report that bioelectrical impedance analysis is useful in the early detection of infiltration at puncture sites. When infiltration was intentionally induced in the vein of a rabbit's ear, impedance parameters showed significant difference before and after infiltration. In particular, the relative resistance at 20 kHz in the vein of rabbit's ear reduced largely at infiltration, decreased slowly, and then stayed at a constant value. This indicates that the vein in the ear of the rabbit is small, and hence the infiltrated intravenous (IV) solution no longer accumulates after 3 minutes of infiltration. However, when infiltration was induced in the vein of a human's forearm, the relative resistance at 20 kHz decreased gradually over time. In the $R-X_c$ graph, the positions in infiltration induced in the rabbit's ear rapidly shifted before and after infiltration whereas the positions in infiltration induced in the human's forearm changed gradually during infiltration. Our findings suggest that bioelectrical impedance analysis is an effective method to detect the infiltration early in a noninvasive and quantitative manners.

• 지질공학
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• 제24권1호
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• pp.1-8
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• 2014

Numerical stability analysis of an unsaturated infinite slope under rainfall-induced infiltration conditions was performed using generalized effective stress to unify both saturated and unsaturated conditions The soil-water characteristic curve (SWCC) of sand with a relative density of 75% was initially measured for both drying and wetting processes. The hydraulic conductivity function (HCF) and suction stress characteristic curve (SSCC) were subsequently estimated. Under the rainfall-induced infiltration conditions, transient seepage analysis of an unsaturated infinite slope was performed using the finite element analysis program, SEEP/W. Based on these results, the stability of an unsaturated infinite slope under rainfall-induced infiltration conditions was examined in relation to suction stress. According to the results, the negative pore-water pressure and water content within the slope soil changed over time due to the infiltration. In addition, the variation of the negative pore-water pressure and water content led to a variation in suction stress and a subsequent change in the slope's factor of safety during the rainfall period.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.71-78
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• 2010

The stability analysis of unsaturated infinite slope under rainfall-induced infiltration condition was performed using the generalized effective stress that unifies both saturated and unsaturated condition recently proposed by Lu and Likos(2004, 2006). The Soil-Water Characteristic Curve (SWCC) of the sand with the relative density of 75% was first measured for both drying and wetting processes. The Hydraulic Conductivity Function (HCF) and Suction Stress Characteristic Curve (SSCC) were subsequently estimated. Also, under the rainfall-induced infiltration condition transient seepage analysis of unsaturated infinite slope was performed using the finite element program, SEEP/W. Based on these results, the stability of unsaturated infinite slope under rainfall-induced infiltration condition was examined considering the suction stress. According to the results, the negative pore water pressure and water content within the soil changed with time due to the infiltration. Also, the variation of those caused the variation of suction stress and then the factor of safety of slope changed consequently during the rainfall period.

• 한국농공학회논문집
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• 제54권5호
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• pp.129-139
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• 2012

Accurate modeling rainfall induced landslide and slope stability requires a detailed knowledge of the distribution of material strength characteristics and suction distribution. However, material properties obtained from the drying cycle are still used for infiltration analysis in many cases, even though material properties of wetting cycle are quite different from those of drying cycle due to hydraulic hysteresis and air occlusion. Therefore, the selection of proper material properties such as soil-water retention curve (SWRC) and the hydraulic conductivity function (HCF) reflecting characteristics of wetting cycle and air occlusion is an essential prerequisite in order to simulate the infiltration phenomena and to predict the suction and water content distribution in unsaturated soils. It is concluded that the simulation of infiltration with material properties from the drying cycle did not reasonably match with experimental outputs. Further discussion is made on how to describe the material properties considering air occlusion during wetting cycle over the entire suction range in order to simulate infiltration phenomena.

• 한국세라믹학회지
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• 제39권7호
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• pp.693-698
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• 2002

반응소결 탄화규소의 잔류 실리콘 양을 최소화하기 위해 3성분계 탄화규소 분말을 혼합하여 최밀 충전 반음소결 탄화규소를 제조하였다. 기지상의 충전밀도 증가로 인해 반응소결 중 실리콘의 불완전 침윤이 발생하였으며, 이로 인한 잔류 기공은 조대 탄화규소 입자의 표면을 따라 존재함을 확인하였다. 불완전 침윤은 승온 중 분해되지 않고 남은 산화물이 실리콘의 용융 온도 이상에서 분해되어 생긴 고립기공에 의한 것으로 확인되었다. 기지상의 표면에 존재하리라 여겨지는 산화물을 제거하기 위해 침윤전 열처리 및 부식처리를 통해 완전침윤을 달성하였다.

• 대한의생명과학회지
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• 제29권3호
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• pp.206-209
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• 2023

Asthma is a chronic and allergic inflammation in the lung, mainly caused by house dust mites (HDM). Recent studies have reported Der p 38 and Der f 38 (Dermatophagoides pteronyssinus and D. farinae, respectively) as crucial allergens of HDMs. This study investigates the different allergic effects of Der p 38 and Der f 38 in an asthma-like mouse model. Lung infiltration of neutrophils was induced by intranasal administration of Der p 38 and Der f 38, with stronger infiltration being observed after exposure to Der p 38. Intranasal and intraperitoneal administration of Der p 38 induced the infiltration of neutrophils and eosinophils in the lung, which was similar to the effect subsequent to Der f 38 administration. Although the number of mast cells was increased, no significant difference was obtained between the effects of both allergens. In TLR4 knockout BALB/c mice, Der p 38 and Der f 38 had no effect on the infiltration of neutrophils, eosinophils, and mast cells. Additionally, allergenicity induced by Der p 38 and Der f 38 in the basophils of Der p38+/Der f 38+ asthmatic subjects was similar, although Der f 38 presented stronger allergenicity in basophils of Der p38+/Der f 38+ allergic patients than Der p 38. These findings contribute to understanding the role of similar allergen components derived from different species in the pathogenesis of allergic diseases.

• 한국농공학회논문집
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• 제49권1호
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• pp.57-65
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• 2007

In Korea, most landslides occurr during the rainy season and have shallow failure planes parallel to the slope. For these types of rainfall-induced failures, the most important factor triggering slope unstability is decrease in the matric suction of unsaturated soils with increasing saturation depth by rainfall infiltration. For this reason, estimation of cumulative infiltration has a significance. In this study, infiltration rate and cumulative infiltration are estimated by using both Mein & Larson model based on Green-Ampt infiltration model and using modified Mein & Larson model to which unsteady rainfall is applied. According to the results, the modified model is more reasonable than Mein & Larson method itself in estimation of infiltration rate and saturation depth because of considering real pending condition.

• 대한두개안면성형외과학회지
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• 제11권2호
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• pp.120-123
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• 2010

Purpose: Epinephrine itself exhibits some cardiotoxicity. However, it rarely induces cardiomyopathy when used in standard doses during surgery for local hemostasis. This paper reports a rare case of stress-induced cardiomyopathy in a young woman after the local infiltration of epinephrine. Methods: Corrective rhinoplasty was planned in a 20-year-old woman. Lidocaine mixed with epinephrine 1:100,000 was injected around the skin of the nose and nasal septum after inducing anesthesia, which resulted in sinus tachycardia and hypotension. Postoperative ECG showed a T wave inversion in the lead V2 and echocardiography revealed transient hypokinesia in the cardiac apex. Cardiac enzyme was mildly elevated. Results: Symptoms and laboratory findings improved considerably, and the patient was discharged from hospital without complications on the sixth day after surgery. Conclusion: The prognosis of catecholamine-induced cardiomyopathy is generally favorable. However, it is important to be aware of the possible adverse effects of local epinephrine infiltration. This case highlights the need for caution when using epinephrine.