• 대한수학교육학회지:학교수학
• /
• 제8권3호
• /
• pp.265-290
• /
• 2006

본 연구의 목적은 엑셀의 활용이 일차함수의 문제해결에 어떤 영향을 미치는가를 알아보는데 있다. 엑셀을 활용한 교수실험 전과 후에 학생들의 함수에 관한 문제해결에서의 변화를 알아보기 위해 사전 사후 문제해결검사를 실시하였다. 문제해결검사 분석은 정확한 과정-대상관점, 근접한 과정-대상관점, 부정확한 과정-대상관점으로 범주화해 이루어졌다. 문제해결검사 분석 결과, 교수실험에 참여한 학생들 모두 일차함수에 관한 문제해결관점이 바람직한 방향으로 변화되었다. 엑셀을 활용한 탐구학습환경이 지필환경의 제한점을 보완할 수 있다는 시사점을 도출하였다.

• Coupled systems mechanics
• /
• 제4권1호
• /
• pp.37-65
• /
• 2015

Modeling and simulation of mechanical response of infrastructure object, solids and structures, relies on the use of computational models to foretell the state of a physical system under conditions for which such computational model has not been validated. Verification and Validation (V&V) procedures are the primary means of assessing accuracy, building confidence and credibility in modeling and computational simulations of behavior of those infrastructure objects. Validation is the process of determining a degree to which a model is an accurate representation of the real world from the perspective of the intended uses of the model. It is mainly a physics issue and provides evidence that the correct model is solved (Oberkampf et al. 2002). Our primary interest is in modeling and simulating behavior of porous particulate media that is fully saturated with pore fluid, including cyclic mobility and liquefaction. Fully saturated soils undergoing dynamic shaking fall in this category. Verification modeling and simulation of fully saturated porous soils is addressed in more detail by (Tasiopoulou et al. 2014), and in this paper we address validation. A set of centrifuge experiments is used for this purpose. Discussion is provided assessing the effects of scaling laws on centrifuge experiments and their influence on the validation. Available validation test are reviewed in view of first and second order phenomena and their importance to validation. For example, dynamics behavior of the system, following the dynamic time, and dissipation of the pore fluid pressures, following diffusion time, are not happening in the same time scale and those discrepancies are discussed. Laboratory tests, performed on soil that is used in centrifuge experiments, were used to calibrate material models that are then used in a validation process. Number of physical and numerical examples are used for validation and to illustrate presented discussion. In particular, it is shown that for the most part, numerical prediction of behavior, using laboratory test data to calibrate soil material model, prior to centrifuge experiments, can be validated using scaled tests. There are, of course, discrepancies, sources of which are analyzed and discussed.