• 한국구조물진단유지관리공학회 논문집
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• 제23권7호
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• pp.152-163
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• 2019

본 연구에서는 강섬유의 혼입, 매트릭스의 압축강도, 전단철근과 전단경간비가 UHPFRC 휨재에 미치는 영향에 대해 총 10개의 실험체에 대한 실험을 통해 검토하였다. 실험결과 2%의 부피비로 강섬유가 혼입된 경우 파괴 패턴을 전단파괴에서 휨파괴로 바꿀 정도로 높은 전단강도 증진효과를 보유하고 있는 것으로 나타났다. 또한 강섬유는 낮은 전단경간비에서 압축스트럿의 파괴를 지연시키는 효과를 가진 것으로 나타났다. 실험 결과 강섬유의 혼입과 전단경간비의 변화에 따라 균열각이 45도보다 낮은 것으로 나타났다. 실험 결과를 UHPC 설계권고안들과 비교해 본 결과 프랑스의 설계권고안은 보수적으로 평가하였고 한국의 설계권고안은 휨 강도에 대해 다소 과대평가하는 것으로 나타났다. 전단강도에 대해서는 두 설계권고안 모두 보수적으로 평가하는 것으로 나타났다.

• Journal of Korean Neurosurgical Society
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• 제37권3호
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• pp.207-212
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• 2005

Objective: Classically, single photon emission tomography is known to be the reference standard for evaluating the hemodynamic status of patients with moyamoya disease. Recently, T2-weighted perfusion magnetic resonance(MR) imaging has been found to be effective in estimating cerebral hemodynamics in moyamoya disease. We aim to assess the utility of perfusion-weighted MR imaging for evaluating hemodynamic status of moyamoya disease. Methods: The subjects were fourteen moyamoya patients(mean age: 7.21 yrs) who were admitted at our hospital between Sep. 2001 to Sep 2003. Four normal children were used for control group. Perfusion MR imaging was performed before any treatment by using a T2-weighted contrast material-enhanced technique. Relative cerebral blood volume(rCBV) and time to peak enhancement(TTP) maps were calculated. Relative ratios of rCBV and TTP in the anterior cerebral artery(ACA), middle cerebral artery(MCA) and basal ganglia were measured and compared with those of the posterior cerebral artery(PCA) in each cerebral hemispheres. Using this data, we analysed the hemodynamic aspect of pediatric moyamoya disease patients in regarding to the age, Suzuki stage, signal change in FLAIR MR imaging, and hemispheres inducing symptoms. Results: The mean rCBV ratio of ACA, MCA did not differ between normal children and moyamoya patients. However the significant TTP delay was observed at ACA, MCA territories (mean = 2.3071 sec, 1.2089 see, respectively, p < 0.0001). As the Suzuki stage of patients is advanced, rCBV ratio is decreased and TTP differences increased. Conclusion: Perfusion MR can be applied for evaluating preoperative cerebral hemodynamic status of moyamoya patients. Furthermore, perfusion MR imaging can be used for determine which hemisphere should be treated, first.

• 대한예방한의학회지
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• 제5권2호
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• pp.93-105
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• 2001

BACKGROUND : Changiga is a hetnal medicine which has been used of the traditional therapeutic agent of asthma. So I examine the effect of Changija on immune Cell&serum OA-specific IgE in BALF in rat asthma model. MATERIAL and METHODS : Rats were sensitized with OA; at day 1 sensitized group and Changiga(CIG) groups were systemically immunized by subcutaneous ingection of 1mg OA and 300mg of Al(OH)3 in a total volume of 2ml. At the same time, 1ml of 0.9% saline containing $6{\times}109$ B. pertussis bacilli was injected by i.p. 14 days, after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerocol containing 2%(wt/vol) OA, A day after local immunization, BAL fluid was collected from the rats. A day after local immunization, rats were orally administered with Changiga extract 14 days, Lymphocyte, CD4+ T-cell CD8+ T-cell counts, CD4+/CD8+ ratio in BALF, change of serum OA-specific IgE level in the peripheral blood were measured and evaluated. RESULT : Changiga showed a suppressive effect on a rat asthme model. Changiga decreased lymphocyte, CD4+ T-cell, CD4+/CD8+ ratio in BALF, serum OA-specific IgE level as compared with the control group, whereas Changiga decreased CD8+ T-cell in BALF with statistical nonsignificance as compared with the control group. CONCLUSION: This study shows that Changiga have a suppressive effect on rat allergic athma model. Changiga would be useful allergic asthma treatment agent.

• 한국농공학회논문집
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• 제58권6호
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• pp.39-45
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• 2016

In this paper, analyzes the characteristics of self-weight consolidation on the dredged clay according to the fines content and falling height. Research was performed with the dredged clay sampled by Sae-mangeum field site. Classification of fines content was performed by sieve analysis test. After adjusting the fine content, self-weight consolidation tests were carried out focussing on the variation of fines content and falling heights. From the test results of the self-weight consolidation test, samples with high fines content had reached sedimentation completion more later than ones with less fine content samples. In other words, the start of self-weight consolidation was slowing down with increasing of fines content. Also, from the test results of calculating the coefficient of sedimentation consolidation, the coefficient value were increased with the fines content increases. In addition, the change of sedimentation ratio and volume ratio showed more higher changed value as the fine content increases. Thus, it is important to consider the fines content when estimate the settlement time of dredged soil in field dredge work.

• 멤브레인
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• 제13권4호
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• pp.268-282
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• 2003

불완전 분리의 실질적인 분리투과 특성을 근거로 하는 모사모델을 이용하여 투과증발 막촉진 에스터화 반응의 실질적인 거동을 연구하였다. 막의 분리효율, 막의 물제거 능력을 모델에 포함시킴으로써 반응모사를 통하여 이들이 막촉진반응에 어떻게 영향을 끼치는지를 체계적으로 관찰할 수 있었다. 막을 통한 비완전분리가 일어날 경우에 초기 반응물 몰비율이 1이 아닐 때 반응 혼합물중 소량으로 존재하는 반응성분이 투과되거나, 혹은 초기 반응물 몰비율이 1인 반응 혼합물중 어느 반응성분이 투과되든지 반응이 완결될 수 없었다. 생성물인 에스터가 물과 함께 일부 투과될 경우 정방향 반응속도를 증가시켜 시간에 따른 반응 전환률을 증가시킨다. 막을 통한 불완전 분리시 막을 통한 투과로 인하여 발생하는 반응혼합물의 부피감소로 인하여 반응성분 뿐 아니라 생성성분의 농도가 증가되는데 이들 농도증가가 반응속도에 상반된 영향을 끼친다; 반응물 농축은 반응속도를 증가시키나 생성물 농축은 역방향의 반응을 촉진시킴으로서 반응속도를 감소시킨다. 반응초기에는 반응물 농축효과가 우세하나 반응이 진행됨에 따라 생성물 농축효과가 우세하여 반응속도를 저하시킴이 모사결과 관찰되었다.

• 한국조경학회지
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• 제28권5호
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• pp.48-57
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• 2000

This paper is dealing with the fundamental properties of planting concrete, replacing the existing cover concrete on the roof of a building. This study is to find out the physical characteristics of the planting concrete and rearing characteristics of the grass throughout the modeling experimental materials. As the results of the experiment, the physical properties of planting concrete show the following results; when the paste to aggregate ratio is 0.2~ 0.4, voids volume : 30~17%, unit weight: 1,710~2,010kg/m3, compressive strength : 45~145kgf/$\textrm{cm}^2$, its pH is more than 11, but is reduced to the proper degree for planting after being neutralized. Kentucky bluegrass covered with planting concrete is grown well. The planting concrete used with blast furnace slag cement shows a better properties at the height, the width and the covering rate by 1.1cm, 0.5mm and 7%, respectively, than those used with ordinary portland cement. Also, the less the paste to aggregate ratio is, the better the plant grows. The orders of the effects of temperature control are as follows; the system of planting concrete with grass>the system of planting concrete without grass>the system of mixed soil>the existed roof system. In case, the planting concrete is placed to the roofs of buildings instead of normal concrete slab, and a number of favorable effect can be expected such as the improvement os environmental factors, the reduction of construction cost, the saving of energy and the reduction of environment load. The future research on the change of a variety of the aggregate conditions and the application of the practical structures should be made, and also the research of the endurance also be performed.

• 한국식품과학회지
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• 제17권6호
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• pp.522-525
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• 1985

건조된 콩우유 비지의 첨가가 두부의 품질(品質)에 어떠한 영향을 미치는지 조사하고자 제조된 두부의 부피, 견고성, 보수력 그리고 관능적 성질을 비교하였다. Acetone으로 세척하여 건조(乾燥)된 비지를 건물량 기준으로 원료(原料) 대두(大豆)에 10-30% 되게 여과된 대두 추출액에 혼합하여 두부를 제조하였을 때 부피 및 보수력(保水力)의 감소와 침입도(針入度)의 증가가 있었다. 건조비지의 혼합비율(混合比率)을 10%로 할때는 침입도(針入度)는 감소하였으나 Sag의 값이 감소함으로서 딱딱함은 오히려 증가하였고 부피의 감소는 비교적 적었다. 또한 관능적(官能的) 성질(性質)인 부서짐성과 과립성이 향상되어 10% 범위 내에서의 건조비지 혼합에 의한 두부제조의 가능성을 보여주었다. 또한 두부의 보수력(保水力) 비교를 위하여 여과지에 비결합수(非結合水)를 흡착시켜 측정함이 간편하며 비교성이 좋은 방법(方法)임이 밝혀졌다.

• 대한한의학회지
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• 제24권3호
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• pp.1-10
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• 2003

Background : Asthma is a chronic inflammatory disorder under immunological influence. Gamichunggumgangwha-tang (CG, Jiaweiqingjinjianghuo-tang) and Gamiyukmigiwhang-tang (YM, Jiaweiliuweidihuang-tang) are herbal tonics for asthma from traditional herbal medicine. Objective : To evaluate the effect of CG and YM on immune cell & serum OA-specific IgE in broncho-alveolar lavage fluid (BALF) in a rat asthma model. Materials and Methods : Rats were sensitized with OA; at day I sensitized group and CG and YM groups were systemically immunized by subcutaneous injection of 1mg OA and 300mg of Al(OH)3 in a total volume of 2ml. At the same time, 1 ml of 0.9% saline containing $6{\times}10^9$ B. pertussis bacilli was injected by Lp. 14 days after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerosol containing 2% (wt/vol) OA. A day after local immunization, BALF was collected from the rats. Rats were orally administered with each of CG and YM extract for 14 days since the day after local immunization. Lymphocyte, CD4＋ T cell and CD8＋ T cell counts, CD4＋/CD8＋ ratio in BALF, change of serum OA-specific IgE level, CD4＋ T cell and CD8＋ T cell percentages in the peripheral blood were measured and evaluated. Results : CG and YM showed an alleviating effect on asthmatic responses of rats. CG decreased total cell, lymphocyte, CD4＋ T cells in BALF, and serum OA-specific IgE level as compared with the control group. YM decreased lymphocytes as compared with the control group. CD4＋/CD8＋ ratio in BALF from the CG and YM groups and serum OA-specific IgE level from the YM group didn't show any significant variation from the control group. Conclusion : CG alleviated asthmatic hyperreactivity of the immune system through CD4＋ T cells and serum IgE. Further the study of this immune system modulating mechanism is expected.

• 상하수도학회지
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• 제18권2호
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• pp.201-207
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• 2004

Dissolved air flotation (DAF) is a solid-liquid separation process that uses fine rising bubbles to remove particles in water. Most of particle-bubble collision occurs in the DAF contact zone. This initial contact considered by the researchers to play a important role for DAF performance. It is hard to make up conceptual model through simple mass balance for estimating collision efficiency in the contact zone because coupled behavior of the solid-liquid-gas phase in DAF system is 90 complicate. In this study, 2-phase(gas-liquid) flow equations for the conservation of mass, momentum and turbulence quantities were solved using an Eulerian-Eulerian approach based on the assumption that very small particle is applied in the DAF system. For the modeling of turbulent 2-phase flow in the reactor, the standard $k-{\varepsilon}$ mode I(liquid phase) and zero-equation(gas phase) were used in CFD code because it is widely accepted and the coefficients for the model are well established. Particle-bubble collision efficiency was calculated using predicted turbulent energy dissipation rate and gas volume fraction. As the result of this study, the authors concluded that bubble size and recycle ratio play important role for flow pattern change in the reactor. Predicted collision efficiency using CFD showed good agreement with measured removal efficiency in the contact zone. Also, simulation results indicated that collision efficiency at 15% recycle ratio is higher than that of 10% and showed increasing tendency of the collision efficiency according to the decrease of the bubble size.

• Journal of Acupuncture Research
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• 제32권2호
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• pp.169-185
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• 2015

Objectives : The purpose of this study is to find the effects of Sa-am liver tonifying and sedating acupuncture on radial pulse. Methods : Sixty healthy people were divided into a liver tonifying acupuncture(LTA) group, liver sedating acupuncture(LSA) group, and control group. The LTA group and LSA group received acupuncture for 20 minutes with a supine position. The Control group took a rest without receiving acupuncture. Radial pulse was measured by three dimensional pulse imaging system(DMP-3000) at four different time points (before, right after, 30 minutes after, and 60 minutes after acupuncture). We compared the three groups and figure out determined the parameters which significantly changed after acupuncture treatment. Results : 1. Pulse period, T1/T, T4/T, (T-T4)/T, T4/(T-T4), T5/T significantly changed after acupuncture. 2. H4, pulse area, systolic pulse area, diastolic pulse area, radial augmentation index(RAI), and pulse power volume / min significantly changed after acupuncture. 3. Frequency of Fourier components, ratio of frequencies of Fourier components, magnitude of Fourier components, and ratio of magnitudes of Fourier components significantly changed after acupuncture. Conclusions : LTA and LSA have an effect on the radial pulse parameters. Further studies on radial pulse change using Sa-Am acupuncture are needed.