• 제목/요약/키워드: S-47

검색결과 9,234건 처리시간 0.034초

이종재료의 알루미늄 이중 외팔보 복합재의 충격 거동 (Impact Behavior at Composite Material of Aluminium Double Cantilever Beam with Two Kinds of Materials)

  • 조재웅
    • 한국산학기술학회논문지
    • /
    • 제8권3호
    • /
    • pp.421-426
    • /
    • 2007
  • 본 연구는 이종재료의 이중외팔보 시험편들을 충격하중으로 실험한 결과들에 대하여 유한요소법으로 동적해석을 하였다. 충격 속도로서는 6.4 및 18.47 m/s를 적용하였고 그 실험 결과와 시뮬레이션 데이터로 상호 비교하였다. 크랙 에너지 해방율과 블록의 힘 및 변형을 컴퓨터로 수치 해석할 수 있었다. 본 논문에서 해석된 시험편의 수치해석 데이터로 실험 데이터에 근접시키게 되는 검증을 함으로서 충격 실험에 대한 수치적 시뮬레이션을 하기에 타당함을 알 수 있었다.

  • PDF

건강증진학교가 학교풍토에 미치는 영향 (Effects of Health Promoting School on School Climate)

  • 박윤주
    • 한국학교보건학회지
    • /
    • 제28권2호
    • /
    • pp.47-55
    • /
    • 2015
  • Purpose: This study aims to explore whether health promoting schools (HPS) affect school climate. The study is the first research that investigates the effects of Korean HPS on school climate. Methods: The study examined 2,791 students who participated in a study on HPS effectiveness conducted by MOE (The Ministry of Education) in 2014. Data were analyzed through descriptive statistics, factor analysis, and ttest using SPSS/WINdow 22.0. Results: There was a significant difference between the HPS and the comparison schools in terms of three school climate criteria ' School atmosphere', 'Teacherstudent relationship', and 'Peer relationship'. Conclusion: The study's result that Korean HPS has positive effects on school climate indicates a need to expand HPS in Korea's education sector.

Infraoptic Course of Both Anterior Cerebral Arteries

  • Ji, Cheol;Ahn, Jae-Geun
    • Journal of Korean Neurosurgical Society
    • /
    • 제47권1호
    • /
    • pp.71-73
    • /
    • 2010
  • A 28-year-old woman was referred to our hospital with a sudden, very severe headache. Brain computed tomographic angiography showed a saccular cerebral aneurysm at the bifurcation of the left middle cerebral artery and infraoptic courses of both anterior cerebral arteries. The anterior cerebral arteries were seen to arise from the ipsilateral internal cerebral arteries at the level of the origin of the ophthalmic artery, passed underneath the ipsilateral optic nerve, and turned upward at ventral portion of the optic chiasm. Infraoptic course of the proximal anterior cerebral artery is an extremely rare anomaly and is often associated with cerebral aneurysms. We report the clinical features, radiological findings, and possible genesis of this anomaly with a literature review.

4-1BB (CD137), an inducible costimulatory receptor, as a specific target for cancer therapy

  • Vinay, Dass S.;Kwon, Byoung S.
    • BMB Reports
    • /
    • 제47권3호
    • /
    • pp.122-129
    • /
    • 2014
  • Although considerable progress has been made in understanding how tumors evade immune surveillance, measures to counter the same have not kept pace with the advances made in designing effective strategies. 4-1BB (CD137; TNFRS9), an activation-induced costimulatory molecule, is an important regulator of immune responses. Targeting 4-1BB or its natural ligand 4-1BB ligand (4-1BBL) has important implications in many clinical conditions, including cancer. In-depth analysis revealed that 4-1BB-mediated anti-cancer effects are based on its ability to induce activation of cytotoxic T lymphocytes (CTL), and among others, high amounts of IFN-${\gamma}$. In this review, we will discuss the various aspects of 4-1BB-mediated anti-tumor responses, the basis of such responses, and future directions.

An Introduction to the Edumatrix Set and Its Didactic Capabilities

  • Semenov, Mikhail;Colen, Yong S.;Colen, Jung;Pardala, Antony
    • 한국수학교육학회지시리즈D:수학교육연구
    • /
    • 제23권1호
    • /
    • pp.47-62
    • /
    • 2020
  • Learning through "recreational mathematics" has become a meaningful outlet to children of all ages. The Edumatrix set is a didactic tool for the development of logical and abstract reasoning among students. In this paper, we provide several illustrative exercises involving Edumatrix that teachers can utilize in their classrooms. We formulate students' expected learning outcomes by aligning each exercise to the CCSSM content standards as well as examining which Standards for Mathematical Practices (SMP) our proposed exercises promote.

1차와 2차 침하를 고려한 압밀침하량 예측 (A Consolidation Settlement Prediction Considering Primary and Secondary Consolidation)

  • 이달원;정성규
    • 한국농공학회논문집
    • /
    • 제47권1호
    • /
    • pp.61-68
    • /
    • 2005
  • In this study, it was proposed that an equation for predicting consolidation settlement on soft clay ground, which separate total settlement into primary and secondary consolidation settlement equation. The consolidation settlements by the proposed equation and by the measured settlements from laboratory model test were compared and verified for its application. It was appeared that the proposed equation from the laboratory model test approach to be more realistic comparing to !the result of Terzaghi's equation. From the above application, it was concluded that the final settlement prediction by. the Hyperbolic, Asaoka methods is needed to the initial settlement but the proposed equation could be much applicable in the lacking condition of measured data of the initial period.

NOAA/AVHRR 위성영상을 이용한 기후학적 물수지 분석 (Climatic Water Balance Analysis Using NOAA/AVHRR Satellite Images)

  • 권형중;신사철;김성준
    • 한국농공학회논문집
    • /
    • 제47권1호
    • /
    • pp.3-9
    • /
    • 2005
  • The purpose of this study was to analyze the climatic water balance of the Korean peninsula using meteorological data and the evapotranspiration (ET) derived from NOAA/AVHRR, Quantifying water balance components is important to understand the basic hydrology, In this study, a simple method to estimate actual ET was proposed based on a regression approach between NDVI and Morton's actual ET using NOAA/AVHRR data, The Mortons actual ET for land surface conditions was evaluated using a daily meteorological data from 77 weather stations, and the monthly averaged Morton's ETs for each land cover was compared with the monthly NDVIs during the year 2001. According to the climatic water balance analysis, water deficit and surplus distributed maps were created from spatial rainfall, soil moisture, and actual and potential ETs map, The results clearly showed that the temporal and spatial characteristics of dryness and wetness may be detected and mapped based on the wetness index.

Analysis of thermo-rheologically complex structures with geometrical nonlinearity

  • Mahmoud, Fatin F.;El-Shafei, Ahmed G.;Attia, Mohamed A.
    • Structural Engineering and Mechanics
    • /
    • 제47권1호
    • /
    • pp.27-44
    • /
    • 2013
  • A finite element computational procedure for the accurate analysis of quasistatic thermorheological complex structures response is developed. The geometrical nonlinearity, arising from large displacements and rotations (but small strains), is accounted for by the total Lagrangian description of motion. The Schapery's nonlinear single-integral viscoelastic constitutive model is modified for a time-stress-temperature-dependent behavior. The nonlinear thermo-viscoelastic constitutive equations are incrementalized leading to a recursive relationship and thereby the resulting finite element equations necessitate data storage from the previous time step only, and not the entire deformation history. The Newton-Raphson iterative scheme is employed to obtain a converged solution for the non-linear finite element equations. The developed numerical model is verified with the previously published works and a good agreement with them is found. The applicability of the developed model is demonstrated by analyzing two examples with different thermal/mechanical loading histories.

Conditions for Preparing Glycyrrhiza uralensis Extract for Inhibiting Biofilm Formation of Streptococcus mutans

  • Ham, Youngseok;Kim, Tae-Jong
    • Journal of the Korean Wood Science and Technology
    • /
    • 제47권2호
    • /
    • pp.178-188
    • /
    • 2019
  • Licorice, which has an extensive history of use as an herbal medicine, has been suggested to have oral health benefits. However, to date, no systematic study has been conducted on the preparation method of licorice extracts for oral health. In this study, licorice extracts prepared using water and ethanol were investigated for its ability to inhibit the biofilm formation of Streptococcus mutans. The licorice extract prepared with around 60% ethanol effectively inhibited the biofilm formation of S. mutans. Licorice extracted with 50% ethanol almost completely inhibited the biofilm formation at 1.5 g/L of licorice extract. This inhibitory activity was confirmed in a microplate assay and a flow cell system. Glycyrrhetic acid was extracted from licorice effectively with 60% ethanol concentration. The strong inhibitory activity of glycyrrhetic acid and the synergistic inhibition with glycyrrhizin on biofilm formation were suggested as major reasons for a concentration-specific extraction. These results suggest that licorice extract prepared using around 60% ethanol effectively inhibits the biofilm formation of S. mutans.