❖ Wikipedia and Social Knowledge Dynamics ❖ Previous Work on Wikipedia – Degree distribution – Reciprocity and feedback loops – Motifs ❖ Modeling Wikipedia’s Growth – A model about reference – A model about degree distribution ❖ AOC-based Models ❖ Conclusion
• Opportunity costs and comparative advantage • An Example • Relative demand-relative supply analysis • A one factor Ricardian model • Production possibilities • Gains from trade • Wages and trade • Misconceptions about comparative advantage • Transportation costs and non-traded goods • Empirical evidence
针对香港风化花岗岩场址勘探,在液压旋转钻机上安装钻孔过程监测系统(drilling process monitoring,DPM),对有效轴压力、钻具转速、冲洗压力、钻头位移及穿孔速率进行了实时监测.采用变斜率作为显著性指数,对地层中的主、次界面进行了识别.t检验表明,DPM系统对岩土界面识别的置信度为99%.此外,对穿孔参数在界面处的变化分析表明,这些参数随孔深的变化曲线在界面处存在不同涨落,轴压力和穿孔速率对界面上岩石强度变化的响应度为81.82%