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961.
《Marine Policy》2017
The Sustainable Development Goals or SDGs [44] are an ambitious step towards sustainable development, taking a much broader view of sustainability than ever achieved previously, yet practical challenges remain, including how to implement change. The aims of this research were to determine how an influential aquaculture company in Australia - Tassal, Tasmania's largest salmon aquaculture company - perceived the SDGs, and to ascertain the motivations and barriers for Tassal to work towards implementing the goals. Interviews were conducted with leaders, employees and external business partners. Tassal was not aware of the SDGs prior to this project, but were open to considering implementing them in their current sustainability practices. The survey responses were analysed using the Values-Rules-Knowledge (vrk) framework of decision making. Key findings were: 1) corporate and personal values were the key component driving Tassal's positive responses to the SDGs; 2) awareness of the SDGs resulted in Tassal recognising the potential gains from engaging with some of the seemingly less aquaculture-related goals (such as health and wellbeing). These findings demonstrate that businesses can fruitfully engage with the SDGs, even without government requirements or societal expectations, if they are prepared to broaden their interpretation of business sustainability and be reflective about their values. The vrk model is a potentially useful addition to current SDG and sustainability tools, such as those of the UN Global Compact, as a way to diagnose organisational barriers to adopting practices aligned with the SDGs. An emerging area of importance to social, economic and environmental sustainability – social license – was also identified as implicit in many, but not explicit in any of the SDGs. 相似文献
962.
改革开放以来,中国不断深化发展开放型经济。十七大报告明确提出"拓展对外开放广度和深度,提高开放型经济水平"。由于受地缘、人缘、政府宏观调控、跨国公司产业配置、国际分工、生产要素全球流动等因素影响,各省市区开放型经济水平存在差异。在前人研究的基础上设计了评价国内各省市区开放型经济水平的指标体系,并采用2004—2008年连续5年的相关数据,用主成分分析法测算出我国各省市区开放型经济水平。最后,对计算结果进行综合评价和分类比较得出若干结论。 相似文献
963.
964.
Northward-shift of temperature zones in China’s eco-geographical study under future climate scenario
Despite the well-documented effects of global climate change on terrestrial species’ ranges, eco-geographical regions as the regional scale of ecosystems have been poorly studied especially in China with diverse climate and ecosystems. Here we analyse the shift of temperature zones in eco-geographical study over China using projected future climate scenario. Projected climate data with high resolution during 1961–2080 were simulated using regional climate model of PRECIS. The number of days with mean daily temperature above 10℃ and the mean temperature of January are usually regarded as the principal criteria to indicate temperature zones, which are sensitive to climate change. Shifts due to future climate change were calculated by comparing the latitude of grid cells for the future borderline of one temperature zone with that for baseline period (1961–1990). Results indicated that the ranges of Tropical, Subtropical, Warm Temperate and Plateau Temperate Zones would be enlarged and the ranges of Cold Temperate, Temperate and Plateau Sub-cold Zones would be reduced. Cold Temperate Zone would probably disappear at late this century. North borderlines of temperature zones would shift northward under projected future climate change, especially in East China. Farthest shifts of the north boundaries of Plateau Temperate, Subtropical and Warm Temperate Zones would be 3.1°, 5.3° and 6.6° latitude respectively. Moreover, northward shift would be more notably in northern China as future temperature increased. 相似文献
965.
钢管混凝土桥墩抗震性能试验研究 总被引:1,自引:0,他引:1
为研究钢管混凝土桥墩的抗震性能,对钢管混凝土桥墩和钢筋混凝土桥墩进行了拟静力对比试验研究。根据试件的破坏发展过程以及各试件的滞回曲线和骨架曲线,分析了其滞回性能、耗能能力、延性、强度退化及刚度退化等抗震性能。试验结果表明,钢管混凝土桥墩的抗震性能明显好于钢筋混凝土桥墩。在含钢率和轴力相同的情况下,钢管混凝土桥墩的滞回曲线比钢筋混凝土桥墩丰满得多,前者的耗能能力约为后者的4.46倍,钢管混凝土桥墩的延性大于钢筋混凝土桥墩;随着轴压比的增大,钢管混凝土桥墩延性有所下降,强度退化加快,但对其刚度退化的影响不大。 相似文献
966.
雪峰山隧道砂板岩各向异性力学特性的试验研究 总被引:4,自引:0,他引:4
利用MTS815 Flex GT岩石力学试验系统,对雪峰山隧道围岩中的砂板岩开展单轴和三轴试验,研究这种砂板岩中的细微层理对岩石变形特性、强度特性及其参数的影响,结果表明:岩石力学特性的各向异性特征显著。层理面与轴向力夹角0°时应力-应变曲线呈不稳定破裂特征,破坏面沿层理面方向发育;夹角90°时曲线呈峰后迅速软化特征,破坏面为对角贯通性剪切破坏。单轴试验中夹角0°的抗压强度比夹角90°高出约20%,弹性模量和变形模量比夹角90°分别约大50%和80%。三轴试验中2种夹角情况破坏时主应力差 相近,夹角0°的弹性模量和变形模量分别比夹角90°时约大6%和20%,围压对砂板岩的各向异性特征有弱化效应。这些结论揭示了该砂板岩各向异性的力学特性,对解决工程实际问题有重要的参考价值 相似文献
967.
诸城市恐龙化石资源非常丰富,全市共发现恐龙化石产地30多处,其中典型的化石产地有"库沟化石长廊"、"恐龙涧隆起带"、"臧家庄化石层叠区"和"黄龙沟足迹化石群"。当地政府为了保护这些珍贵的化石资源,采取了许多行之有效的保护措施,但在保护过程中发现仍然存在一些不足之处。该文根据目前保护现状,针对保护中存在的主要问题,进行深入分析查找原因,提出可行性措施。 相似文献
968.
969.
基于Hyperion高光谱与ALOS全色波段的融合图像,运用线性波谱分离模型,对影响城市下垫面分类的因子进行定量分析。结果显示:随着空间分辨率的递增,融合图像光谱保真性呈下降之势,并呈现出阈值现象,但所有相关系数值都大于0.90,表明以融合图像进行线性波谱分离提取城市下垫面具有可靠性;下垫面分类总精度则整体明显下降,Kappa系数值也几乎单调减少。大气校正后下垫面分类的总精度和Kappa系数都明显高于大气校正前;当丰度分割值由10%增至60%时,生成的下垫面分类图像的精度单调降低,表明应慎用50%阈值分割法。 相似文献
970.
Stephane Rodrigues Nicolas Claude Philippe Juge Jean‐Gabriel Breheret 《地球表面变化过程与地形》2012,37(2):240-248
Field investigations that help clarify local sedimentary processes involved in the migration of alternate bars as a consequence of flood events are lacking. A simple approach combining scour chains, stratigraphy and frequent bathymetric surveys is proposed to connect the dynamics of free migrating alternate bars present in disconnected channels of large sandy‐gravelly rivers with their sedimentary products and vice versa. The results show that the spatial distribution of bars before a flood partly governs the scour and fill processes and that the sediment transport rates vary significantly on a single cross‐section. This can be due to preferential axes of the migration of the bars determined by their location on the cross‐section, the bank direction and the discharge. The approach allows the reconstruction of local sedimentary processes involved in alternate bar migration by combining maximum scour depths reached during a flood with frequent channel bed topography surveys and post‐flood stratigraphy. It is also possible to distinguish deposited and preserved sediments compared with sediments by‐passed during the flood. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献