切削变形规律观测装置的设计与实验分析

根据实验教学的经验,研究了金属切削过程中采集试样标本的“快速落刀”装置和制备试样样本的镶嵌机,并进行了切削变形规律观察和测量,取得了一定的实验效果,设计的两种装置,被用于本科生的实验教学和研究生的课题实验中,由于它制造容易,成本价低,结构简单,使用方便,采集和制备试样稳靠,作为本科生课堂的实验装置和研究生的课题试验装置是可行的.     

凌源毛家店矿区金矿成矿规律与找矿方向探讨

毛家店金矿床位于凌源——喜峰口金成矿带的北东部，受区域构造控制，为与燕山期二长花岗岩和八道河群变质杂岩有密切成因联系的含金石英脉型金矿床。通过对矿床地质特征的分析，进一步总结该区金矿成矿规律，初步认为区内的隐伏矿床具有良好的找矿前景。     

动态数据的规则提取

近年来利用粗集理论提取决策规则的方法得到广泛研究。但到目前为止对于大量的动态数据如股票数据的规则提取，一般的粗集方法不一定有效。因为已经提取的规则对于后来的未知数据可能太大或包含很多杂乱的不正确的规则，从而就产生这样的问题，即如何尽可能有效地将从已知数据中获取的规则应用于未知数据。文中提出一种动态约简的方法产生有效的决策规则，用以匹配未知数据。该方法经实验验证，具有高效、准确的特点。     

An Antidiffusive Entropy Scheme for Monotone Scalar Conservation Laws

In a recent work J. Sci. Comput. 16, 479–524 (2001), B. Després and F. Lagoutière introduced a new approach to derive numerical schemes for hyperbolic conservation laws. Its most important feature is the ability to perform an exact resolution for a single traveling discontinuity. However their scheme is not entropy satisfying and can keep nonentropic discontinuities. The purpose of our work is, starting from the previous one, to introduce a new class of schemes for monotone scalar conservation laws, that satisfy an entropy inequality, while still resolving exactly the single traveling shocks or contact discontinuities. We show that it is then possible to have an excellent resolution of rarefaction waves, and also to avoid the undesirable staircase effect. In practice, our numerical experiments show second-order accuracy.     

论政府投资项目招标相应的法制

深入研究政府投资项目招标的法规体系,防范政府在投资项目招标中的腐败行为,有利于政府行为的规范化.     

Reprint of “Media reporting of traffic legislation changes in British Columbia (2010)”

IntroductionIn 2010, British Columbia (BC) introduced new traffic laws designed to deter impaired driving, speeding, and distracted driving. These laws generated significant media attention and were associated with reductions in fatal crashes and in ambulance calls and hospital admissions for road trauma.ObjectiveTo understand the extent and type of media coverage of the new traffic laws and to identify how the laws were framed by the media.MethodsWe reviewed a database of injury related news coverage (May 2010–December 2012) and extracted reports that mentioned distracted driving, impaired driving, or speeding. Articles were classified according to: (i) Type, (ii) Issue discussed, (iii) ‘Reference to new laws’, and (iv) ‘Pro/anti traffic law’. Articles mentioning the new laws were reread and common themes in how the laws were framed were identified and discussed.ResultsOver the course of the study, 1848 articles mentioned distraction, impairment, or speeding and 597 reports mentioned the new laws: 65 against, 227 neutral, and 305 supportive. Reports against the new laws framed them as unfair or as causing economic damage to the entertainment industry. Reports in favor of the new laws framed them in terms of preventing impaired driving and related trauma or of bringing justice to drinking drivers. Growing evidence of the effectiveness of the new laws generated media support.ConclusionsBC's new traffic laws generated considerable media attention both pro and con. We believe that this media attention helped inform the public of the new laws and enhanced their deterrent effect.     

带强迫项的KdV方程的非线性自伴随性和守恒律

应用非线性自伴随性的概念和伊布拉基莫夫的一般守恒律定理，研究了带强迫的KdV方程的非线性自伴随性和守恒律。首先讨论了自伴随性，结果表明这个方程具有非线性自伴随性，同时得到了这个方程的形式拉格朗日量。在对这个方程进行李对称分析之后，根据李对称的不同得到了这个方程的一些非平凡守恒律。     

蹬空上提面矿压显现规律的数值模拟研究

提高工作面回采上限是节约煤炭资源的重要途径之一。针对既蹬空又提高上限的工作面,回采前需研究其矿压显现规律。通过FLAC3D数值模拟能很好地分析蹬空、上提对工作面回采的影响。数值计算结果表明:蹬空上提段超前支承压力峰值较蹬空非上提段大,蹬空上提对工作面顶板下沉量的影响较蹬空非上提大。