• 제목/요약/키워드: Experimental formula

검색결과 1,066건 처리시간 0.024초

청피(靑皮)의 실험적(實驗的) 연구(硏究) ( I ) (A Experimental Study on the Citri Reticulatae Viride Pericarpium( I ))

  • 강성용;이원석;정현우;한종현
    • 대한한의학방제학회지
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    • 제8권1호
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    • pp.329-342
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    • 2000
  • Citri Reticulatae Viride Pericarpium(CRVP) is being used to regulate the flow of Q(氣) However, the mechanism of it's pharmacological actions is not well understood. The purpose of this research was to investigate effects of CRVP contractil response of isolated on abdominal and femoral artery in rabbits and renal artery in pigs. 1. Abdominal artery was relaxed by CRVP in a dose-dependent manner. 2. Femoral artery was relaxed by CRVP in a dose-dependent manner 3. Pretreatment with methylene blue and indomethacin did not inhibited CRVP induced relax in abdominal artery and femoral artery. 4. Renal artery was relaxed by $H_{2}O$ fraction in a dose-dependent manner, 5. Pretreatment with regitine inhibited $H_{2}O$ fraction(CRVP) induced relax in renal artery in a dose-dependent manner. 6. Renal artery was not relaxed by hexane fraction(CRVP) in a dose-dependent manner. 7. Pretreatment with regitine$(10^{-7}M)$ was relaxed by methylene chloride(MC)(CRVP) and $H_{2}O$ fraction in a $0.5{\mu}g/m{\ell}$.

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한약 탕전 팩의 미생물 연구 (Observation of Microorganism in Herbal Decoction mafactured by Korean Medical Clinic)

  • 유영법;마진열;하혜경;황대선;김복규;신광수;신현규
    • 대한한의학방제학회지
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    • 제15권2호
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    • pp.119-126
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    • 2007
  • Objectives: This study presents observation of microorganism such as total aerobic bacteria, total fungus, E. coli, Pseudonomas aerugjnosa, Staphylococcus aureus, and Salmonella typhimurium in herbal decoction manufactured by Korean medical clinic. Methods: We examined to observe microorganism using the requirements for the experimental methods recommended by FDA. For the identification, we observed microscopic methods and carried out polymerase chain reaction (PCR) and DNA purification. The purified DNA samples were analyzed by DNA sequencer. As compared with NCBI database. the results were identified by sequences similarity. Results and conclusion: 26 (55%) of 46 decoctions observed positive for microbial test. 12 (46 %) of 26 positive decoctions exceed requirement of microbial limit test. These microbial colony identified genus of Bacillus using microscopic and DNA sequencing methods.

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Cyclic tests and numerical study of composite steel plate deep beam

  • Hu, Yi;Jiang, Liqiang;Zheng, Hong
    • Earthquakes and Structures
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    • 제12권1호
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    • pp.23-34
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    • 2017
  • Composite steel plate deep beam (CDB) is proposed as a lateral resisting member, which is constructed by steel plate and reinforced concrete (RC) panel, and it is connected with building frame through high-strength bolts. To investigate the seismic performance of the CDB, tests of two 1/3 scaled specimens with different length-to-height ratio were carried out under cyclic loads. The failure modes, load-carrying capacity, hysteretic behavior, ductility and energy dissipation were obtained and analyzed. In addition, the nonlinear finite element (FE) models of the specimens were established and verified by the test results. Besides, parametric analyses were performed to study the effect of length-to-height ratio, height-to-thickness ratio, material type and arrangement of RC panel. The experimental and numerical results showed that: the CDBs lost their load-carrying capacity because of the large out-of plane deformation and yield of the tension field formed on the steel plate. By increasing the length-to-height ratio of steel plate, the load-carrying capacity, elastic stiffness, ductility and energy dissipation capacity of the specimens were significantly enhanced. The ultimate loading capacity increased with increasing the length-to-height ratio of steel plate and yield strength of steel plate; and such capacity increased with decreasing of height-to-thickness ratio of steel plate and gap. Finally, a unified formula is proposed to calculate their ultimate loading capacity, and fitting formula on such indexes are provided for designation of the CDB.

계절변화에 따른 PSC 균형 켄틸레버 교량의 장기거동 특성 (Long-term Behavior of FCM Bridges considering Seasonal Temperature Variation - Part 1)

  • 이선호;이학은
    • 한국방재학회 논문집
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    • 제1권2호
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    • pp.93-101
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    • 2001
  • 본 연구에서는 계절에 따른 온도 변화를 고려한 건조수축의 예측모델을 제시하여, 실제구조물에서의 계절에 따른 온도변화에 대한 장기 거동 특성을 보다 향상된 방법으로 파악할 수 있는 방법을 제시하였다. 본 연구에서 사용된 건조수축 보정계수식은 계절에 따른 온도변화를 포함한 건조수축의 실제 실험적 데이터들을 사용하여 제안되었으며, FCM 교량의 장기 거동 조사는 현장에서 건조수축의 수치해석 결과를 적용할 수 있는지 없는지를 결정하기 위해 수행되었다. 본 연구에서 채택된 수치해석 방법은 실제 변형율과 차이가 발생하는 일반적인 방법과는 달리 실제 구조물의 거동특성을 매우 유사하게 모사할 수 있는 것으로 나타났다. 결과적으로 본 연구에서 제안된 방법은 FCM 교량의 장기 처짐에 대한 예측을 향상 시킬 것이다.

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이진 기수 조건에서 인접성 표현을 위한 최적화된 CNF 변환 (Optimal CNF Encoding for Representing Adjacency in Boolean Cardinality Constraints)

  • 박사천;권기현
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제35권11호
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    • pp.661-670
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    • 2008
  • 만족가능성 처리기는 모델 검증 및 임베디드 프로그램 검증과 같이 소프트웨어 공학의 여러 분야에서 활용되고 있다. 만족가능성 처리기를 활용하기 위해서는 주어진 문제를 처리기의 입력인 CNF 형식으로 변환해야 한다. 그러나 이 형식은 소스코드나 소프트웨어 모델보다 표현력이 낮기 때문에 최적화된 변환이 요구된다. 본 논문에서는 "n개에서 인접된 $k{\leq}n$개 선택" 문제를 CNF형식으로 변환하는 최적화된 기법을 제시한다. 제안된 방법을 다양한 일본 퍼즐에 적용한 결과 우수한 성능이 입증되었다. 우리가 알고 있는 한, 인접성에 대한 최적화된 CNF 변환 연구는 거의 없다.

편심이 고려된 강관-가셋트 접합부의 극한 내력 (A Study on the Ultimate Strength of Tube-Gusset Connection Considering Eccentricity)

  • 김우범
    • 한국강구조학회 논문집
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    • 제13권2호
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    • pp.201-210
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    • 2001
  • 본 연구에서는 편심 축력을 받는 가셋트-강관 접합부의 극한 내력을 파악하기 위하여 실험 및 유한요소해석을 수행하였다. 가셋트-강관 접합부의 내력에 영향을 주는 요소는 강관의 직경, 가셋트판 길이, 축력과 횡력의 비, 횡력에 의한 편심 등으로 이들이 주재의 좌굴내력에 미치는 영향을 정량적으로 파악하여 접합부 강도식을 제안하였다. 특히 횡력에 의한 편심이 주재에 작용할 때 이를 설계식에 반영하기 위하여 횡력을 등가의 모멘트 및 편심 축력으로 대치한 수치 모형을 제시하였다. 결과적으로 접합부의 작용하는 외력을 주주재 축력, 모멘트, 편심 축력으로 분해하고 각 외력에 대한 독립적인 극한내력을 구한후 이들의 상관 관계식을 구함으로써 접합부 극한강도식을 제시하였다.

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Curvature ductility of high strength concrete beams according to Eurocode 2

  • Bouzid, Haytham;Kassoul, Amar
    • Structural Engineering and Mechanics
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    • 제58권1호
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    • pp.1-19
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    • 2016
  • Recently, the high-strength concrete is increasingly used in the construction of reinforced concrete structures due to its benefits, but this use is influenced negatively on the local ductility of structural elements. The objective of this study is the prediction of a new approach to evaluate the curvature ductility factor of high strength concrete beams according to Eurocode 2. After the presentation of the Constitutive laws of materials and the evaluation method of curvature ductility according to the Eurocode 2, we conduct a parametric study on the factors influencing the curvature ductility of inflected sections. The calibrating of the obtained results allows predicting a very simple approach for estimating the curvature ductility factor. The proposed formula allows to calculate the curvature ductility factor of high strength concrete beams directly according to the concrete strength $f_{ck}$, the yield strength of steel $f_{yk}$ and the ratio of tension and compression reinforcements ${\rho}$ and ${\rho}^{\prime}$ respectively, this proposed formula is validated by theoretical and experimental results of different researchers.

Composite action of hollow concrete-filled circular steel tubular stub columns

  • Fu, Qiang;Ding, Fa-xing;Zhang, Tao;Wang, Liping;Fang, Chang-jing
    • Steel and Composite Structures
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    • 제26권6호
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    • pp.693-703
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    • 2018
  • To better understand the influence of hollow ratio on the hollow concrete-filled circular steel tubular (H-CFT) stub columns under axial compression and to propose the design formula of ultimate bearing capacity for H-CFT stub columns, 3D finite element analysis and laboratory experiments were completed to obtain the load-deformation curves and the failure modes of H-CFT stub columns. The changes of the confinement effect between core concrete and steel tube with different hollow ratios were discussed based on the finite element results. The result shows that the axial stress of concrete and hoop stress of steel tube in H-CFT stub columns are decreased with the increase of hollow ratio. AfteGr the yield of steel, the reduction rate of longitudinal stress and the increase rate of circumferential stress for the steel tube slowed down. The confinement effect from steel tube on concrete also weakened slowly with the increase of hollow ratio. Based on the limit equilibrium method, a simplified formula of ultimate bearing capacity for the axially loaded H-CFT stub columns was proposed. The predicted results showed satisfactory agreement with the experimental and numerical results.

국내학술지에 발표된 한약추출물의 골다공증에 대한 효능실험 결과 고찰 (A review of anti-osteoporosis effects of herbal extracts in Korean journals)

  • 안지영;기지예;김주호;박혜정;김현주;이정호;김윤경
    • 대한한의학방제학회지
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    • 제16권2호
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    • pp.47-69
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    • 2008
  • Objectives : The purpose of this study is to inspect trends of the papers of osteoporosis in the field of herbal medicines and to establish the future direction for evaluation and development of natural medicines. Methods : We reviewed 80 oriental medicine papers in Korean journals published between 1994 and 2008. Results : There were 6 review, 2 clinical paper, 72 experimental papers and we confirmed that the drugs used in the experiments are almost yang-invigorating drugs which are good for kidney deficiency pattern Conclusions : We found out some of the herbal extracts are very efficacious for osteoporosis. More studies of oriental medicinal herbs are needed for developing anti-osteoporosis drugs with these basic data.

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화개산(華蓋散)의 항염에 대한 실험적 연구 (The Experimental study of Hwagae-san on Anti-Inflammatory Effect)

  • 노운섭;신조영;이시형
    • 대한한의학방제학회지
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    • 제16권2호
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    • pp.101-114
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    • 2008
  • Objective : The purpose of this study was to investigate the anti-inflammatory effects of Hwagae-san extract(HGSE) on the peritoneal macrophage. Methods : To evaluate anti-inflammatory effects of HGSE, We measured cytokines(interleukin-6; IL-6, interleukin-12; IL-12, tumor necrosis factor-${\alpha}$; TNF-${\alpha}$) and nitric oxide(NO) production in lipopolysaccharide(LPS)-induced macrophages. Furthermore, We examined molecular mechanism using western blot and also LPS-induced endotoxin shock. Results : 1. HGSE did not have any cytotoxic effect in the peritoneal macrophages. 2. HGSE reduced LPS-induced IL-6, TNF-${\alpha}$, IL-12 and NO production in peritoneal macrophages. 3. HGSE inhibited the activation of extracelluar signal-regulated kinase(ERK), C-Jun NH2-terminal kinase(JNK) but not of p38, degradation of IkB-${\alpha}$ in the LPS-stimulated peritoneal macrophages. 4. HGSE inhibited the production of TNF-$\alpha$, IL-6 and IL-12 in serum after LPS injection. Conclusion : These results suggest that HGSE may inhibit the production of TNF-${\alpha}$, IL-6, and IL-12 through inhibition of ERK and JNK activation, and that HGSE may be beneficial for inflammatory diseases.

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