基于台风危害的厦门地区园林树木受损 原因研究

基于2016年9月16日1614号台风对厦门绿地的严 重影响，通过为期2个月对台风现场实地调研以及相关部门抢 险的数据统计，第一时间了解此次台风中厦门重要园林树种的 受害状况，分析树木在台风中的受损原因。台风灾害发生后给 厦门市的园林树木以及景观带来巨大的损害，因此对于厦门地 区园林树木受损原因的研究非常有必要。研究了受损原因后， 才可以在灾前以及灾后对重要的园林树木种进行栽培养护管 理，增加厦门绿化的抗灾能力以及灾后的及时恢复工作。     

基于数字图像处理技术的再生混凝土数值模拟

为了研究骨料形态对再生混凝土材料力学性能的影响,基于势能原理的基面力元法,利用图像处理技术和MATLAB软件,建立了再生混凝土真实骨料细观模型。应用FORTRAN分析软件对再生混凝土试件进行单轴拉伸试验的数值模拟,研究了真实骨料细观模型再生混凝土宏观应力-应变曲线变化规律和试件的破坏形态。结果显示,真实骨料模型得到的宏观应力-应变曲线和试验曲线吻合度较高,骨料形状对试件的破坏形态影响较小。模型可真实地模拟再生混凝土在单轴拉伸作用下的损伤破坏过程,准确地反映试件的实际骨料形态。     

Loss and damage: a critical discourse analysis of Parties’ positions in climate change negotiations

The years-long negotiations on loss and damage (L&D) associated with climate change impacts reached a milestone with the adoption of the Paris Agreement, sanctioning the permanence of the Warsaw International Mechanism (WIM) created in 2013. The WIM aims at advancing knowledge gathering, coordination and support to address L&D associated with extreme and slow onset events in vulnerable developing countries (Decision 2/CP.19). Despite being among the most controversial issues to be recently treated in climate change negotiation, L&D has attracted little attention in the field of international relations. This paper aims at addressing this gap by reconstructing the emergence and evolution of the negotiating positions on L&D of developing and developed countries. It employs a critical discourse analytical approach and builds on Fairclough’s three-dimensional framework for critical discourse analysis, taking decision 2/CP.19 as the core communicative event. Consistently, the decision is analysed at three different levels: as a text (micro-scale); as a discursive practice (meso-scale); and as a social practice (macro-scale). The analysis makes use of a wide range of materials including previous decisions, High Level Segment statements and Parties submissions. It reconstructs Parties’ conflicting views on the positioning of L&D vis-à-vis the adaptation space (L&D as a part of, or as beyond adaptation) and the scientific, ethical and legal arguments employed to support these standpoints. It highlights, in particular, the strategic importance which the ‘compensation argument’ had in determining developing countries’ capacity to influence the UNFCCC process up to the inclusion of a specific article on L&D in the Paris Agreement. While calls for compensation might have lost momentum as a result of the Warsaw and Paris talks, the paper argues that their potential is far from exhausted. They in fact imply a more general request for climate justice which the UNFCCC has not yet addressed.     

基于模态应变能密度理论的网架结构损伤识别方法

为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。     

侵权行为的经济分析

经济分析法学是西方法学界和经济学界发展最快的领域之一,运用经济学的方法对法律问题加以阐释,效率与均衡被认定为法律制度的核心理念。特别是在侵权领域引入经济学理论,对侵权行为的责任承担、损害赔偿的事后研究转向了事先分析。因此,从预防成本与预防收益之间的关系对侵权行为的归责原则进行效率分析,并借助“亨德公式”对两种不同的损害赔偿进行经济界定,权衡由侵权行为引起的社会成本差异,当预防的成本小于预防的预期收益,侵权人的预防是必要的、有效率的。如未采取有效的预防措施,侵权人的行为就是无效的,就要受到法律的惩罚。     

Stability of international environmental agreements under isoelastic utility

There is now a growing consensus that ratifying International Environmental Agreements (IEAs) is the most effective way to tackle transboundary pollution problems. While the social benefit function (SBF) critically affects emission choices as well as decisions to ratify IEAs, the related economic literature has mainly concentrated on scenarios where the marginal SBF is linear. Using climatic data, I find that the linear marginal SBF case does not match data and isoelastic SBFs fit data better. In the more realistic, but not yet explored, context of isoelastic SBFs, I reconsider incentives to ratify IEAs. My analysis gives rise to novel conclusions. For instance, changes in the scale of damages do not affect the level of cooperation. When the scale of damages is small, variations of the SBF parameter reveal that large coalitions including the coalition of all countries are stable, but only when the potential gain from cooperation is sufficiently high.     

A Question of Integrity: Variants of Bt Cotton,Pesticides and Productivity in Pakistan

Bt cotton remains one of the most widely grown biotech crops among smallholder farmers in lower income countries, and numerous studies attest to its advantages. However, the effectiveness of Bt toxin, which depends on many technical constraints, is heterogeneous. In Pakistan, the diffusion of Bt cotton occurred despite a weak regulatory system and without seed quality control; whether or not many varieties sold as Bt are in fact Bt is also questionable. We utilise nationally representative sample data to test the effects of Bt cotton use on productivity. Unlike previous studies, we invoke several indicators of Bt identity: variety name, official approval status, farmer belief, laboratory tests of Bt presence in plant tissue, and biophysical assays measuring Bt effectiveness. Only farmer belief affects cotton productivity in the standard production model, which does not treat Bt appropriately as damage‐abating. In the damage control framework, all Bt indicators reduce damage from pests. Biophysical indicators have the largest effect and official approval has the weakest. Findings have implications for impact measurement. For policy‐makers, they suggest the need, on ethical and productivity grounds, to improve variety information and monitor variety integrity closer to point of sale.     

220kV线路故障跳闸分析

本文介绍了一起由于平整土地过程中挖掘机与导线之间的电气距离不够造成的线路跳闸故障,从管理角度出发,提出了具体的防范措施,为降低该类故障总结了经验。     

百口泉71井区储层保护技术研究应用

通过室内实验研究,明确储层特征及敏感性情况,系统分析了储层损害机理,并结合超前注水,研究制定出"先期防膨、早期分注"与"控制注水强度、保持注采平衡"对策措施,形成了先期分层、梯度式防膨与后期注水过程中段塞脉冲式防膨相结合的工艺技术,确定了合理的注入压力和注入量等参数。投入现场实施后效果显著,百71井区白碱滩组油藏注入压力保持稳定,吸水状况良好,动用程度良好。     

基于 BP 神经网络的结构损伤识别研究

针对结构的损伤识别进行了研究，选取结构固有频率平方变化比作为特征参数，建立12×25×1 BP网络结构，采用均方误差函数目标误差函数，学习函数选取梯度下降动量学习函数和L-M优化算法，对四层钢框架结构的损伤进行了检测。