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301.
The complex and controversial task of selecting a dam site in a river basin can be successfully achieved using science-informed multi-criteria decision-making (MCDM) techniques. In this paper, we describe the application of the group fuzzy TOPSIS model for optimal ranking of the case study of Kandoleh dam sites in Kermanshah province, Iran, involving 18 input criteria. In this study, decision-making committee was made up of 20 involved decision makers. The comments of four non-biased, external experts in dam site selection were also used. The triangular fuzzy numbers were used to apply experts’ opinions on the selection criteria. In total, four alternative sites were assessed based on the technical, economic, social and environmental considerations and the data were analyzed using fuzzy TOPSIS MCDM model. Ranking results were compared with multi-criteria decision-making models, including the ELimination and Choice Expressing the REality and simple additive weighting. This logical, open and transparent framework provides a science-informed decision-making approach for complex problems such as optimal dam site selection. Finally, using sensitivity analysis, local studies and group discussions, we demonstrated the multiple benefits of the proposed novel method for a science-informed, open and transparent method for optimal ranking of the dam site candidates.  相似文献   
302.
Cryptocurrencies have the potential to revolutionize the exchange of information and money through blockchain and distributed ledger technologies. Despite the promise of such underlying technologies, their reliance upon distributed consensus processes to approve software updates raises the potential for governance failures to destabilize a given cryptocurrency. These governance failures, known as ‘hard forks,’ can separate a cryptocurrency into two rival camps. Where such events can destabilize a given cryptocurrency’s value, and instill distrust in the capacity of a cryptocurrency to survive as a reliable vehicle of exchange, it is imperative for the cryptocurrency community to improve their governance processes and limit the potential for hard forks to occur. While the distributed nature of cryptocurrency governance makes any traditional governing process unlikely to succeed, anticipatory approaches that establish thresholds and metrics to determine when software reform is necessary may help alleviate the governance failures presented by many hard forks.  相似文献   
303.
The economy and well-being of modern societies relies on complex and interdependent infrastructure systems to enable delivery of utilities and movement of goods, people and services. This complexity has resulted in an increased potential for cascading failures, whereby small scale initial failures in one system can result in events of catastrophic proportions across the wider network. Resilience and the emerging concept of resilience engineering within infrastructure are among the main concerns of those managing such complex systems. However, the disparate nature of resilience engineering development in various academic and industrial regimes has resulted in a diversity of definitions and characterisations. These are discussed in this paper, as are the commonalities between sectors and between different engineering disciplines. The paper also highlights the various methodologies used as part of resilience engineering implementation and monitoring, current practices including existing approaches and metrics, and an insight into the opportunities and potential barriers associated with these methodologies and practices. This research was undertaken for the Resilience Shift initiative to shift the approach to resilience in practice for critical infrastructure sectors. The programme aims to help practitioners involved in critical infrastructure to make decisions differently, contributing to a safer and better world.  相似文献   
304.
Flood resilience has been rising up the political, economic and social agendas. Taking an integrated systems approach, using the right design guidance and tools and ensuring that education is in place for all stakeholders are three themes which are intrinsically linked to delivering flood resilience. This paper reviews these themes across the academic research, policy landscape and practitioner approaches, drawing conclusions on the way forward to increase our societies resilience to floods. The term ‘flood resilience’ is being increasingly used, however, it remains to be clearly defined and implemented. The UK, USA and Australia are leading the way in considering what flood resilience really means, but our review has found few examples of action underpinned by an understanding of systems and complexity. This review investigates how performance objectives & indicators are currently interpreted in guidance documents. It provides an in-depth exploration of the methods, that although developed through European and US expertise, can be used for worldwide application. Our analysis highlights that resilience is often embedded in engineering education and frequently linked to risk. This may however, mask the importance of resilience and where it differs from risk. With £2.6 billion to be spent in the UK over the next 6 years on strengthening the country’s flood and coastal defences, this is the opportunity to rethink resilience from a systems approach, and embed that learning into education and professional development of engineers. Our conclusions indicate how consolidating flood resilience knowledge between and within critical infrastructure sectors is the way forward to deliver flood resilience engineering.  相似文献   
305.
306.
Gary Francione is an abolitionist: he maintains that we ought to abolish the institutions and practices that support the exploitation of animals. He also believes that veganism is the “moral baseline”—that is, he thinks it’s morally required of nearly everyone in the developed world, and many beyond it. Luis Cordeiro-Rodrigues claims that abolitionism is guilty of racism, albeit “racism without racists.” I contend that his arguments for this conclusion aren’t successful.  相似文献   
307.
Many alpine ski areas have recently adopted voluntary environmental programs (VEPs) such as using recycling, renewable energy, and biofuels to help reduce their environmental impacts. Studies have addressed the performance of these VEPs in mitigating environmental impacts of this industry, but little is known about visitor awareness and perceptions of these programs. This article addresses this knowledge gap by exploring skier and snowboarder knowledge of VEPs at a ski area and the influence of these programs on their motivations to visit this area currently and behavioral intentions to visit again in the future. Data were obtained from an onsite survey at the Mt. Bachelor ski area in Oregon, USA (n = 429, 89.7% response rate). Few skiers and snowboarders were knowledgeable of VEPs at this area and fewer than 20% were motivated to visit on their current trip because of these programs. Other attributes such as scenery, snow conditions, and access were more important for influencing visitation. Up to 38% of skiers and snowboarders, however, intend to visit this ski area more often if it adopts and promotes more VEPs. Managers can use these results to inform communication and marketing of their environmental programs and performance to visitors. Additional implications for management and future research are discussed.  相似文献   
308.
There is evidence of continued food insecurity and malnutrition in Pakistan despite significant progress made in terms of food production in recent years. According to “Vision 2030” of the Planning Commission of Pakistan, about half of the population in the country suffers from absolute to moderate malnutrition, with the most vulnerable being children, women, and elderly among the lowest income group. The Government of Pakistan has been taking a series of policy initiatives and strategic measures to combat food insecurity issues. These range from increasing production to food imports, implementation of poverty reduction strategies, nutritional improvement programs, as well as provision of social safety nets. The article aims to instill some fresh thinking into the debate regarding the challenges of food security. It underscores the limitations of hitherto policy response, and suggests crucial measures to improve the present grim scenario. Policy makers, planners, practitioners, and academicians in countries with comparable socio-political and economic setup can view this discussion as a case study and may apply the findings in their domain accordingly.  相似文献   
309.
Over the past few decades, recreation and tourism use has increased at many marine protected areas, generating concerns about impacts of this increasing use on experiences and conditions at these areas (e.g., crowding, conflict). This article uses data from Molokini Shoal Marine Life Conservation District in Hawai’i to examine: (a) reported encounters, crowding, normative tolerances for various use levels, and support of use related management strategies at this site; and (b) whether users who encounter higher use levels than their norms feel more crowded and are more supportive of restrictive management strategies. Data were obtained from onsite pre-trip and post-trip questionnaires of 712 passengers on commercial snorkel and dive tours visiting this site. Norms were measured with acceptance of 12 photographs depicting levels of boat use. On average, users would accept seeing no more than approximately 16 boats at one time at Molokini and this number was observed on over 20% of trips to the site. Although the majority of users expected to escape crowds at Molokini, 67% felt crowded and up to 79% supported actions that would directly restrict use at this site (e.g., limit number of boats). Users who encountered more boats than their normative tolerance felt more crowded and were more supportive of these management strategies. Findings suggest that this marine protected area is operating over its capacity and management is needed to improve experiences and conditions.  相似文献   
310.
We investigated the type and extent of degradation at three sites on the Agulhas Plain, South Africa: an old field dominated by the alien grass Pennisetum clandestinum Pers. (kikuyu), an abandoned Eucalyptus plantation, and a natural fynbos community invaded by nitrogen fixing—Australian Acacia species. These forms of degradation are representative of many areas in the region. By identifying the nature and degree of ecosystem degradation we aimed to determine appropriate strategies for restoration in this biodiversity hotspot. Vegetation surveys were conducted at degraded sites and carefully selected reference sites. Soil-stored propagule seed banks and macro- and micro-soil nutrients were determined. Species richness, diversity and native cover under Eucalyptus were extremely low compared to the reference site and alterations of the soil nutrients were the most severe. The cover of indigenous species under Acacia did not differ significantly from that in reference sites, but species richness was lower under Acacia and soils were considerably enriched. Native species richness was much lower in the kikuyu site, but soil nutrient status was similar to the reference site. Removal of the alien species alone may be sufficient to re-initiate ecosystem recovery at the kikuyu site, whereas active restoration is required to restore functioning ecosystems dominated by native species in the Acacia thicket and the Eucalyptus plantation. To restore native plant communities we suggest burning, mulching with sawdust and sowing of native species.  相似文献   
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