• 제목/요약/키워드: Investigate

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홍화의 항혈전작용에 대한 실험적 연구 (An Experimental Study on the Antithrombotic Effects of CARTHAMUS TINCTORIUS)

  • 안종석;황치원
    • 대한한의학회지
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    • 제21권4호
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    • pp.47-54
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    • 2000
  • Objectives: The purpose of this study was to investigate the antithrombotic effect of Carthamus tinctorius. Methods: SD rats were used to investigate the inhibitive effect of platelet aggregation (in vitro & in vivo), prothrombin time, platelet count. Mice were used to investigate the survival rate after injection of collagen & epinepbrine. Results: 1. The inhibitive effect of platelet aggregation (in vitro & in vivo) were increased significantly in all groups. 2. Prothrombin time was decreased in both groups. 3. Platelet count was decreased significantly in sample A. 4. Survival rate after injection of collagen & epinepbrine was increased in sample B. Conclusion: According to the above results, it is suggested that Carthamus tinctorius has antithrombotic effects.

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혼합모래를 사용한 콘크리트의 강도 특성 (Compressive Strength Characteristics of Concrete Using in Crushed Sand)

  • 백동일;염치선;김명식;김종수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.731-734
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    • 2005
  • Crushed sand is blended in order to investigate the quality changes and characteristics of concrete with variation of blend ratio of crushed sand (50, 60, 70, 80, 90, $100\%$). Slump and air content were measured to investigate properties of fresh concrete, and unit weight, compressive strength and modulus of elasticity in age of 7, 28, 60, 90, 180 days were measured to investigate properties of hardened concrete. Compressive strength, unit weight and modulus of elasticity were increased as time goes by and they are expected to keep on increasing in long-term age as well. As a result of measuring compressive strength and modulus of elasticity in age of 7, 28, 60, 90, 180days, compressive strength was highest when it is $70\%$ of blended ratio.

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유한요소해석을 이용한 형상기억합금의 열적/기계적 거동 연구 (Thermomechanical Behaviors of Shape Memory Alloy Using Finite Element Analysis)

  • 윤성호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.833-836
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    • 2001
  • The thermomechanical behaviors of the shape memory alloy were conducted through the finite element analysis of ABAQUS with UMAT user subroutine. The unified thermomechanical constitutive equation suggested by Lagoudas was adapted into the UMAT user subroutine to investigate the characteristics of the shape memory alloy. The three cases were solved to investigate the thermomechanical characteristics of the shape memory alloy. The material properties for the analysis were obtained by DSC and DMA techniques. According to the results, the thermomechanical characteristics, such as a shape memory effect and a pseudoelastic effect, could be obtained through the finite element analysis and the analysis results were revealed to agree well with the experimental results. Therefore, the finite element analysis using UMAT user subroutine is one of prominent analysis techniques to investigate the thermomechnical behaviors of the shape memory alloy quantitatively.

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Fall arresting system

  • Leamon, T.S.;Malone, C.;Son, D.H.
    • 대한인간공학회지
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    • 제10권1호
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    • pp.23-28
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    • 1991
  • A major inhibition of past work in a slip/fall accident study has been due to the lack of a facility and a methodology to experimentally investigate such behavior without expowting human subjects to the natural danger of injury resulting from a fall. In order to carry out a slip/fall research, a unique facility must be created specially to investigate falling and slipping behavior. One component of this facility will be used to focus a research towards experimental investigations of the basic mechanisms involved in falls. Especially, this compo- nent must be designed, developed, and fabricated to provide passive, reactive support at the point of loss of ba- lance. This component must allow both normal and reduced friction surfaces to be designated to investigate human falling in the experimental conditions. This study will address how a fall arresting system was designed and it would be implemented in actual case of a slip/fall study.

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에너지절약을 위한 열차운행전략에 관한 시뮬레이션 연구 (A Simulation Study on the Energy Saving Strategy of Train Operation)

  • 주영복;최규형
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.1594-1598
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    • 2007
  • Energy saving is an important topic for each heavy user of the power system, including railway operators. Therefore, four strategy of train operations studied that maximum speed reduction, reduced acceleration rate, anticipatory coasting, and saw-tooth coasting for energy saving. The Simulation model of the study used to investigate the performance of a railway system, and it was used to study the effect of energy saving strategies for the train operation. The Study investigate train operation strategy for energy saving, investigate the effect of strategy, and find the energy optimization of acceleration, coasting, braking section used Run-Curve simulator from train data.

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드라이클리닝에 의한 미생물 제거효과(제1보) (Effect of Drycleaning on the Removal of Microorganisms (Part 1))

  • 신정숙;차옥선
    • 한국의류학회지
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    • 제19권3호
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    • pp.548-559
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    • 1995
  • The purpose of this study was 1) to investigate the effect of drycleaning on the removal of microorganisms according to on the conditions or the kinds of drycleaning solvent about the Quantity of microorganism which remains in kinds of the drycleaning solvent and the sludge after drycleaning. 2) to investigate the removal effect of :microorganisms in using drycleaning solvent repeatedly 3) to investigate the kinds of microorganism living in textiles. The re, ;ultras of tai, ; study were as follows; 1) less microorganisms remains in perchloroethylen than in petroleum solvent. The most microorganisms was isolated at the beginning stage during the drycleaning. 2) In fresh drycleaning solvents, Pseudomonas aeruginosa ATTIC 27853, taphylococcsu atreus ATTIC 6538. and Candida albicans 10529 were killed immediately, while in case of pesters solvents used for 6 month-drycleaning, Pseudomonas Aeruginosa ATTIC 27853 were survived a lot of still in 17 days. 3) On the kind of bacteria in textile goods, Pseudomonas acidovorans and Ewsipelothrix rhusiopathiae are isolated. a genus Rhodetorula is observed through microscope. On the kind of fungi in textile goods, genus Penicillins and genus Apergillus are found through microscope, genus Caddie and genus Trichophyton are found with shapes.

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원심형 날개를 부착한 축류홴의 유동특성 해석 (Analysis of Flow Characteristics on the Axial Flow Fan with Centrifugal Blade)

  • 최중근;이석종;이명호;성재용
    • Journal of Advanced Marine Engineering and Technology
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    • 제30권5호
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    • pp.589-596
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    • 2006
  • This study aims to propose a new model axial flow fan which attachs centrifugal blades, and to investigate the effect of centrifugal blades on the performance improvement of new model axial flow fan. A numerical simulation has been conducted using STAR-CD commercial code to solve the three dimensional incompressible Navier-Stokes equation for high Reynolds number $k-{\epsilon}$ turbulent model. Numerical simulation is carried out to investigate the detail phenomenon in the flow field and performance characteristics of new model and normal model fan. Calculation results are compared with normal model's results to investigate which centrifugal blades effect on velocity profile and pressure distribution at various flow field positions. and calculation results show that new model fan can improve the performance of total pressure.

자동차탑재용 컴펙트 디스크 플레이어의 진동특성 연구 (The Vibration Study on Car Compact Disk Player)

  • 이태근;김병삼
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.283-288
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    • 2006
  • This study developes the vibration model to estimate the vibration energy of damper/spring assembly(mainbase assembly) for car CD player, and this model is verified by experiment. From frequency response, response, we investigate the natural frequency and mode shape in the up/down direction. In order to determine the analysis frequency band, we investigate the excitation frequency from the vehicle test. As the characteristics of damper and spring is changed, we carry out the vibration test(transmissibility) and investigate the change of transmissibility.

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스테이션 분포형태가 DMSA 프로토콜의 성능에 미치는 효과에 대한 시뮬레이션 연구 (A Simulation Study on the Effects of Station Distribution Patterns to the Performance of DMSA Protocol)

  • 주기호
    • 공학논문집
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    • 제2권1호
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    • pp.95-102
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    • 1997
  • 본 논문은 랜덤 억세스 LAN 프로토콜인 DMSA 시스템에서 스테이션 분포형태의 효과에 대하여 분석한다. 몬테카를로 시뮬레이션기법을 이용하여 몇가지 스테이션 분포 형태에 대하여 각 스테이션의 utilization을 평가한다. 또한, 스테이션의 숫자가 시스템의 utilization-delay 성능에 미치는 효과를 분석한다.

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피리캐스트 Girder-Beam 접합부에서 Girder Ledge의 거동에 관한 실험적 연구 (An Ezperimental Study on the Behavior of Girder Ledge of Precast Girder-Beam Connection)

  • 김기범;박성무
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.483-491
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    • 1997
  • The purpose of this study id to define the behavior of the girder ledge of precast girder-beam joint in Frame Type Precast Concrete Construction Method. And in behavior, girder ledge is different with bracket, because of longitudinal effective width and longitudinal bending. specif c objectives of this study are followed: $\circled1$ To investigate the effects of concrete compressive strength on the maximum shear strength of girder ledge, $\circled2$ To investigate the effects of the shear-span ratio and effective area on behavior of girder ledge, $\circled3$ To investigate the effects of the types of reinforcement on behavior and maximum shear strength of girder ledge, $\circled4$ To study the applicable possibility of the suggested shear friction formulas to estimating the shear strength of girder ledge.

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