Assessing sustainability in nature-inspired design

In the field of sustainable product development, a new perspective for approaching sustainability has been advocated, challenging designers and engineers to aim beyond ‘reducing unsustainability’. Several design strategies – including Biomimicry and Cradle to Cradle – have been suggested for developing truly sustainable, or ‘beneficial’, products. But do these strategies help in developing such products, and how to assess their ‘sustainability’? Based on a review of the objectives in nature-inspired design, we argue that assessing environmental sustainability is not straightforward. Whereas both Biomimicry and Cradle to Cradle build on the perspective of ‘achieving sustainability’, current life-cycle assessment-based tools are geared towards reducing current impacts. As a consequence, existing tools are insufficiently equipped for the purpose of the assessment: they do not cover some of the main results that nature-inspired design is set out to accomplish. To be able to include these results, we propose two new constituents to current life-cycle-based product assessment: assessing against conditions of sustainability and assessing ‘achievement’, the extent to which these conditions of sustainability have been achieved. Furthermore, the product context needs to be included for assessing beneficial impacts. This article discusses how these constituents can contribute to an assessment tool that enables designers and engineers to assess the development of environmentally sustainable solutions.     

基于差异进化支持向量机的坑外土体沉降预测

就用支持向量机(SVM)预测基坑外土体沉降而言,通过差异进化(DE)算法构造适合的决策函数十分重要。在确定坑外土体沉降函数的基本形式下,进行参数反演。后将得到的解析式作为SVM的决策函数,再进行核函数转换,从而使SVM的曲线拟合更加快速,预测更加准确。对大连地铁湾家车站基坑坑外土体的沉降数据的分析及预测的结果表明,使用SVM-DE算法在计算数据量、计算消耗时间和预测精度方面优于2种方法单独使用。     

新型带弹簧支撑抗冲击研究及其在泥石流拦挡坝中的应用

为了使结构或构件能够更好地承受住泥石流、爆炸等冲击荷载,设计出一种新型带弹簧的支撑(件)。运用显式动力分析方法,对冲击载荷作用下的这种支撑进行数值模拟,计算得到新型支撑的动力响应,并与普通支撑进行对比分析。结果表明,新型支撑能更好地防止冲击荷载作用下的结构过早发生塑性变形。另外,在泥石流防治结构中,引入这种新型支撑,设计出新型泥石流拦挡坝。运用有限元软件ls-dyna对新型泥石流拦挡坝进行大块石冲击模拟,并与普通重力式拦挡坝进行对比分析,得出新型拦挡坝坝底应力远小于普通泥石流拦挡坝的应力。研究结果表明,新型带弹簧支撑及新型泥石流拦挡坝的抗冲击效果非常明显。     

PCA-SVR在煤层瓦斯含量预测中的应用

针对煤层瓦斯含量与其影响因素之间存在着复杂的非线性关系,建立了基于主成分分析和支持向量回归机的煤层瓦斯含量预测模型。该模型有效地解决了小样本、非线性预测的问题,并发挥了主成分分析法消除输入变量间相关性的优点,减少了输入变量个数,提高了预测精度和收敛速度。通过实证分析,该模型的预测精度高,能够直接用于煤矿现场预测煤层瓦斯含量。     

基于支持向量机的室内轰燃预测模型研究

为对室内轰燃进行准确预测,针对室内轰燃样本的不足在一定程度上制约了其应用,为此运用SVM技术构建室内轰燃预测的数学模型。在小样本条件下,应用工具软件LIBSVM进行仿真,并将SVM模型预测结果和人工神经网络预测结果进行对比。结果显示,SVM技术能较好地解决小样本和模型预测精确度之间的矛盾,SVM模型其预测精度及可行性高于神经网络模型。实例表明,由于室内火灾受多种因素影响,传统的预测方法存在一定的局限性,而SVM模型预测法预测的结果与试验结果比较一致。     

Modeling and safety strategy of passenger evacuation in a metro station in China

The construction of metro in China is in a period of an unprecedented development in recent years, and the passengers are in high density within the metro during the operation time, the problem of occupant safety in emergencies has attracted more and more attentions. During the design and operation stages, modeling of the metro station evacuation capacity by using the computational models is an effective measure for guaranteeing the metro evacuation safety in the future. In this article, the safety strategy of evacuation in metro stations is first investigated and established, which involves the occupants needed to be evacuated, the evacuation route, and the safety zone. Then, an engineering calculation method for the metro station evacuation time is proposed. Based on the experimental data, simulation of evacuation process in different fire cases is conducted by using an agent-based model, so as to study the features of occupant evacuation behavior, the evacuation time, the passage flow rate, and the strategy of using the escalator as evacuation passage. These conclusions will be helpful for guiding the safe evacuation design of metros in China.     

Influence of laneway support spacing on methane/air explosion shock wave

A laneway support system provides an available way to solve problems related to ground movements in underground coal mines, but also poses another potential hazard. Once a methane/air explosion occurs in a laneway, inappropriate design parameters of the support system, especially the support spacing, likely have a negative influence on explosion disaster effects. The commercial software package AutoReaGas, a computational fluid dynamics code suitable for gas explosions, was used to carry out the numerical investigation for the methane/air explosion and blast process in a straight laneway with different support spacing. The validity of the numerical method was verified by the methane/air explosion experiment in a steel tube. Laneway supports can promote the development of turbulence and explosion, and also inhibit the propagation of flame and shock wave. For the design parameters in actual laneway projects, the fluid dynamic drag due to the laneway support plays a predominant role in a methane/air explosion. There is an uneven distribution of the peak overpressure on the same cross section in the laneway, and the largest overpressure is near the laneway walls. Different support spacing can cause obvious differences for the distributions of the shock wave overpressure and impulse. Under comparable conditions, the greater destructive effects of explosion shock wave are seen for the laneway support system with larger spacing. The results presented in this work provide a theoretical basis for the optimized design of the support system in coal laneways and the related safety assessments.     

浅谈海洋石油多功能支持平台的安全管理

简单介绍了海洋石油多功能支持平台的基本情况,总结了多功能支持平台现有的三种安全管理工具,分别是工作许可证、工作安全风险分析(JSA)和"五想五不干"行为安全观察卡;同时结合海洋石油多功能支持平台自身特点,分析了如何做好平台的安全教育培训、安全检查和班组安全建设以及应急演练等安全管理工作;通过增强全员的安全意识、及时消除事故隐患及增强基层的安全管理和加强平台的应急反应能力,提高海洋石油多功能支持平台的安全管理水平,以期达到海洋石油平台安全、健康、和谐发展的目的,可供同行借鉴和参考。     

新型大采高钻采法采煤机工业试验及工作面安全监测研究

国内外尚没有一种很好地适应厚煤层中小型矿井短壁开采的采煤工艺和综采设备,晋城煤业集团研制的新型高效一次采全高钻采法采煤机及其配套设备可解决这一难题。将新型采煤机在大采高综采工作面进行了工业试验,结果表明,首创"采内放外"采煤工艺的新型钻采法采煤机,具有先进性、低耗能性,经济高效。工作面矿压实测结果表明:工作面老顶为II级老顶,来压显现明显;回采期间,巷道支护效果良好;液压支架工作阻力具有良好的安全储备,能够有效地控制顶板,保证工作面安全,为新型采煤机的安全开采提供设备支持;新型采煤机安全高效开采表明其具有广阔应用前景。     

煤矿巷道支护动态信息设计法

由于地下工程环境的复杂性和不确定性,采用的静态信息设计方法存在着明显的缺陷。因此,提出巷道支护动态信息设计法,其实施过程为:在地质调查和地质力学测试的基础上,采用数值模拟和工程类比相结合的方法进行初始设计;将初始设计实施于井下,并进行地质资料的现场再收集和工程监测;用监测结果检验和修正初始设计,按修正后的设计进行施工,并进行工程监测,如此不断循环,直至完工。该方法在煤炭行业获得成功,在金属矿山、交通、水利等岩土工程中有重要的推广价值。