• Journal of Adhesion and Interface
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• v.13 no.1
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• pp.17-23
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• 2012

A fragrant microcapsule was prepared for use by students to reduce the stress of taking examinations. Rosmarinic acid was used as a fragrant oil which had the effect of relaxing stress, polycaprolactone (PCL) was used as a capsule wall material, and poly(vinyl alcohol) (PVA) as a stabilizer. The solvent evaporation method was used to form the microcapsule. The microcapsules were prepared by changing the stirring rate, the concentration of the stabilizer, and the molecular weight of PCL. The shape of the microcapsule was characterized by scanning electron microscopy (SEM). The size of the microcapsule was reduced by increasing the stirring speed. The release rate of rosmarinic acid was decreased when the higher molecular weight PCL was used. When the prepared microcapsule was tested in an aromatherapy class, the microencapsulated fragrant oil had a longer release time than the original fragrant oil. The study data showed that this fragrant oil was effective for increasing concentration ability, reducing stress, increasing digestive power, and increasing memory for the students.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.303-312
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• 2022

In this study, Cyperus rotundus (C. rotundus) was fractionated into ethyl acetate to identify α-cyperone, a representative indicator, and its ethyl acetate fraction were evaluated to confirm the possibilityas a functional cosmetic ingredient. As a result of HPLC analysis, it was confirmed that the content of α-cyperone was 5.243%. In order to verify the inflammatory relief effect of the ethyl acetate fraction from C. rotundus (EAFC) and α-cyperone, it was confirmed that nitric oxide (NO) production inhibitory ability in RAW 264.7 macrophages induced an inflammatory reaction with lipopolysaccharide (LPS). Real-time qPCR analysis confirmed inhibition of mRNA expression level of inflammatory factors, IL-1β, IL-6, TNF-α, COX-2 and iNOS. As a results of conducting a clinical study using a simple cosmetic formulation containing EAFC, it was confirmed that the skin irritation stimulated by sodium lauryl sulfate (SLS) was calming and relieving itching. Through these results, it is believed that the C. rotundus can be used as a natural cosmetic ingredient that has the effect of inhibiting inflammation and relieving itching.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.2
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• pp.74-81
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• 2017

An off-site consequence analysis is used to calculate the risks when hazardous chemicals that is being used on-site has been exposed off-site; the biggest factor that impacts the risk is the risks of accident scenarios. This study seeks to calculate risks according to accident scenarios by applying OGP/LOPA risk calculating methods for similar facilities, calculate risk reduction ratio by inspecting applicable IPL for incidents, and propose an appropriate risk standard for different risk calculating methods. Considering all applicable IPL when estimating the safety improvement of accident scenarios, the risk of OGP is 8.05E-04 and the risk of LOPA is 1.00E-04, According to the case of IPL, the risk is 1.34E-02. The optimal risk level for accident scenarios using LOPA was $10^{-2}$, but the appropriate risk criteria for accident scenarios in foreign similar studies were $10^{-3}{\sim}10^{-4}$, the risk of a scenario can be determined at an unacceptable level. When OGP is applied, it is analyzed as acceptable level, but in case of applying LOPA, all applicable IPL should be applied in order to satisfy the acceptable risk level. Compared to OGP, the risk is high when LOPA is applied. Therefore, the acceptable risk level should be set differently for each risk method.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.1
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• pp.79-88
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• 2015

This study numerically examined the mixing characteristics of rectangular cavity flows by using the hybrid lattice Boltzmann method (HLBM) applied to the finite difference method (FDM). Multi-relaxation time was used along with a passive scalar method which assumes that two substances have the same mass and that there is no interaction. First, we studied numerical results such as the stream function, position of vortices, and velocity profile for a square cavity and rectangular cavity with an aspect ratio of 2. The data were compared with previous numerical results that have been proven to be reliable. We also studied the mixing characteristics of a rectangular cavity flow such as the concentration profile and average Sherwood number at various Pe numbers and aspect ratios.

• The Journal of Internal Korean Medicine
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• v.21 no.2
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• pp.227-234
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• 2000

독성약물에 의한 급성신부전시 세뇨관세포의 물질 재흡수 장애에 대한 단삼(丹參) 추출액의 효과를 조사하였다. 토끼에 수은(HgCl2)을 10 mg/kg되게 피하 주사하여 급성신부전을 유발하였고, 단삼(丹參) 추출액의 효과는 수은을 주사하기 전 7일 동안 0.05% 액(液) 0.3 g/kg 용량을 경구 투여하여 관찰하였다. 수은을 주사하기 전 24시간 동안 요와 혈액을 채취하여 신장기능을 측정하여 대조기간(basal period)의 값으로 하였고, 수은을 주사한 후 24시간 동안 요와 혈액을 얻어 수은에 의한 신장기능 변화를 평가하였다. 수은을 처리한 후 사구체여과율이 대조값에 비해 감소하였고, 혈청내 creatinine 농도가 증가하였다. 이러한 결과들은 수은이 급성신부전을 유발하였음을 가리킨다. 수은을 처리한 동물에서 포도당 및 인산의 배설분율이 증가하였고, 이러한 변화는 brush-border membrane에서 물질의 이동장애와 Na-pump 활성의 감소에 기인하였다. 수은을 주사한 동물의 신장피질 절편에서 유기이온인 PAH와 TEA 이동이 억제되었다. 토끼의 신장조직에서 지질의 과산화가 수은을 주사한 후 증가하였다. 단삼(丹參) 추출액을 전 처리한 후 수은을 주사한 경우 수은에 의해 유발된 사구체여과율의 감소와 혈청내 creatinine 농도 증가 현상이 유의하게 완화되었다. 수은에 의한 세뇨관에서 물질의 재흡수 장애가 단삼(丹參) 추출액의 전처리에 의해 방지되었다. 단삼(丹參) 추출액은 수은에 의한 지질의 과산화를 억제하였다. 수은에 의한 급성신부전은 항산화제로 잘 알려진 DPPD에 의해 방지되었다. 이상의 결과를 종합하면 생체실험결과 수은에 의한 급성신부전의 유발과정에 지질의 과산화가 중요한 역할을 할 가능성을 보이고 있고, 단삼(丹參) 추출액은 수은에 의한 급성신부전을 방지하는 효과를 가지고 있으며, 그 효과는 단삼(丹參)의 항산화작용에 기인(起因)할 가능성이 많다.

• Journal of the Korean Ceramic Society
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• v.36 no.1
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• pp.61-68
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• 1999

To analyze several defects and residual stress in sintering of layer structure materials, multiayer materials with TZP/SUS and ZT/SUS, and bilayer materials with porcelain/alumina and porcelain/Y-TZP were fabricated by sintering method. Multilayer materials prepared by pressureless sintering show the sintering defect such as warping, splitting, cracking originated from the difference of sintering shrinkage between each layer, which could be controlled by the adjustment of number and thickness in interlayer. In tape casting, a certain pressure given during sintering relaxed the sintering defects, specially warping. The residual stress in bilayer was examined with Vickers indentation method. A small tensile stress in porcelain/alumina and a large compressive stress in porcelain/Y-TZP were generated on the porcelain interface due to the thermal expansion mismatch, which affected the strength of bilayer materials. As a consequence, the sintering defects of multilayer materials and the residual stresses of bilayer materials were dominantly influenced on material design and starting material constants.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.212-223
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• 2021

This study has purposes : evaluating how safe the skin is when applied with the Spicules-containing cosmetic, and whether Diamond-spicules is permeated into the skin and showed the efficacy of the active ingredients well. For these aims, women in their 30s and 60s were surveyed for skin irritation and changes after applying cosmetics to their skin for four weeks. As a result, Spicules-containing cosmetics were safer on the skin than general functional cosmetics, and in particular, in the case of cosmetics containing Diamond-spicules, statistically significant results (p<.001) were obtained in improvement of anti-wrinkle, firmness, moisturizing, whitening, alleviation of inflammation, and sensitivity. Thus, It has been proved Diamond-spicules containing functional active ingredients, not only as transdermal delivery system, but also can be used as multifunctional cosmetic material.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.396-396
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• 2022

생물전기화학적 혐기성소화(Bioelectrochemical anaerobic digestion; BEAD)는 소량의 전압공급을 통해 고농도 하·폐수의 효과적인 처리 및 에너지 회수가 가능한 처리방법으로, 기존 하·폐수처리공정(활성슬러지 및 그 변법)에서 벗어나기 위한 방법 중 하나로 연구되고 있지만, 내부저항 및 전극구조에 따른 물질전달저해로 인해 소규모 연구 위주로 진행되었다. 하지만 stainless steel(SS) 등 내부저항을 완화할 수 있는 전극재료 및 전극구조 개선 연구가 진행됨에 따라 BEAD 적용규모가 증가하는 추세이며, 본 연구에서는 100 L의 용량에서 전극재질 및 구조에 따른 적용적합성을 에너지효율 비교를 통해 평가하였다. 반응조는 비교를 위한 AD, 반응조 내부에 전극을 설치한 BEAD, 반응조 외부에 전극이 포함된 반응조를 추가한 ABEAD로 구성하였으며, AD 및 BEAD는 기계적 교반, ABEAD는 기계적 교반 및 펌프를 통한 bulk 용액 순환으로 물질전달이 이뤄졌다. 또한 BEAD는 탄소계 전극, ABEAD는 SS계 전극을 사용하였으며 두 반응조 모두 0.4 V의 전압을 공급하였다. 실험조건은 유효용량 100 L, 유기물부하율 3 kg/m³/d, HRT 20 days 및 중온소화(35℃)으로 운전하였다. 실험결과 AD, BEAD 및 ABEAD의 유기물제거율은 각각 평균 68.1 %, 68.9 %, 74.9 %로 전극 및 반응조의 분리를 통해 물질전달을 개선한 ABEAD에서 증가하였다. 에너지 생성량의 경우 AD에 비해 BEAD는 평균 229 kJ/d, ABEAD는 309 kJ/d가 추가 생성되었으며 유기물제거율이 높은 ABEAD에서 더 높은 에너지생산이 이뤄졌다. 마지막으로 전압공급으로 인한 에너지소비량은 BEAD는 평균 3.4 kJ/d, ABEAD는 평균 0.9 kJ/d로 전극의 낮은 생물적합성으로 인해 전극에서의 생화학반응이 적은 ABEAD가 에너지소비량이 낮았다. 따라서 본 연구에서는 SS 전극의 사용가능성 및 전극구조 개선에 따른 에너지효율성 향상을 확인할 수 있었으며, 추후 연구에 활용할 수 있을 것으로 기대된다.

• Journal of Korean Biological Nursing Science
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• v.14 no.2
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• pp.129-138
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• 2012

Purpose: Cachexia is a complex metabolic syndrome associated with wasting of skeletal muscle which contributes to nearly one-third of all cancer deaths. Cachexia lowers the frequency of response to chemotherapy and radiation and ultimately can impact survival as well as quality of life during treatment. NF-kappa B is one of the most important molecular mediators of cachexia. In this study, therefore, possible candidates for inhibitors of NF-kappa B were searched. Methods: Amino acids that regulate cellular redox potential by adjusting the level of NAD/NADH ratio, such as aspartate, pyruvate, and isocitrate were selected. Results: Pyruvate effectively inhibited luciferase activity in TNF-stimulated 293T cells transfect with an NF-kB dependent luciferase reporter vector. Pyruvate also showed protective effect on muscle atrophy of differentiated C2C12 myocyte induced by TNF/IFN. Conclusion: We might be able to develop the nutritional management strategy for cancer cachexia patients with pyruvate supplementation.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.194-200
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• 1999

An elastomeric bushing is a device used in automotive suspension systems to cushion the force transmitted from the wheel to the frame of the vehicle. A bushing is an elastomeric hollow cylinder which is bonded to a solid metal shaft at its inner surface and a metal sleeve at its outer surface. For axial motion case, the relation between the force applied to the shaft and their relative displacement was considered. In this paper, the relation between the moment applied to the shaft and their relative deformation(angle of rotation) is considered for the torsional motion case. Numerical solutions of the boundary value problem represent the exact bushing response for use in the method for determining the moment relaxation function of the bushing. Solutions also allow for comparison between the exact moment-deformation behavior and that predicted the proposed model. It is shown that the predictions of the proposed moment-deformation relation are in very good agreement with the exact results.