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61.
Long steel piles with large diameters have been more widely used in the field of ocean engineering.Owing to the pile with a large diameter,soil plug development during pile driving has great influences on pile driveability and beating capacity.The response of soil plug developed inside the open-ended pipe pile during the dynamic condition of pile-driving is different from the response under the static condition of loading during service.This paper addresses the former aspect.A numerical procedure for soil plng effect prediction and pile driveability analysis is proposed and described.By taking into consideration of the pile dimension effect on side and tip resistance,this approach introduces a dimensional coefficient to the conventional static equilibrium equations for the plug differential unit and proposes an improved static equity method for the plug effect prediction.At the same time,this approach introduces a simplified model by use of one-dimensional stress wave equation to simulate the interaction between soft ping and pile inner wall.The proposed approach has been applied in practical engineering analyses.Results show that the calculated plug effect and pile driveability based on the proposed approach agree well with the observed data. 相似文献
62.
T. A. Stadnyk 《水文研究》2024,38(5):e15166
Issues surrounding gender equality are—and should be—front and centre in the water resources community, and other science, technology, engineering and mathematics (STEM) fields. Very necessarily, the focus tends to be on recruitment, offering support for students and early career academics. The leaky pipeline concept used to describe the incremental loss of women from STEM fields with career duration describes a disproportionate loss of senior women, creating a parallel problem where highly qualified, top tier academics are lost from the system after significant financial and personnel investment by institutions. Ultimately, the leaky pipeline undermines the extensive investment of the hydrology and other STEM communities in equity, diversity, inclusion and accessibility (EDIA) recruitment and retention programmes by cutting short career ambitions and the trajectories of diverse top performing individuals, resulting in no net benefit of EDIA policy investments and a lack of diversity with seniority. Addressing this critical gender gap requires the attention and support of the hydrology community of practice with specific focus on generating opportunities for advancement, confronting systemic and structural biases and improving education around allyship. Institutions and professional organizations need to consciously grow diversity in leadership and recognize and outwardly manage the perception of academic excellence around slow research and education that attracts increased diversity. Supporting allyship, reducing competitiveness among community members and reinforcing collaboration will not only attract, but retain, a higher proportion of diversity in the hydrology community, academia and STEM professions in general. It is time for the water resources (and other STEM) communities to demand broader accountability and recognition of the barriers to women, implement and reward more diverse definitions of research excellence, and offer allyship training to the community of practice at large. 相似文献
63.
Finn Arler 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):131-144
Geografisk Tidsskrift, Danish Journal of Geography 106(2): 131–144, 2006 The subject of this paper is long-term large-scale changes in human society. Some very significant examples of large-scale change are presented: human population growth, human appropriation of land and primary production, the human use of fossil fuels, and climate change. The question is posed, which kind of attitude is appropriate when dealing with large-scale changes like these from an ethical point of view. Three kinds of approaches are discussed: Aldo Leopold's mountain thinking, the neoclassical economists' approach, and finally the so-called Concentric Circle Theories approach. It is argued that the last of these three approaches must be preferred, even though further interpretation will be needed in relation to specific decision-making. 相似文献
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Marcos Luna 《The Professional geographer》2013,65(2):282-294
This article presents an analysis of representational equity within the Boston Region Metropolitan Planning Organization (MPO). MPOs are regional transportation organizations that exert significant influence over state transportation planning and the allocation of funding. The analysis shows that under almost any voting or membership configuration, population representation is correlated with racial and ethnic composition. This outcome is not just a function of the system of representation but also the geography of residential segregation. The results of this analysis highlight the problem of creating systems of equitable representation within the context of preexisting and persistent social inequalities. 相似文献
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《Climate Policy》2013,13(4):339-354
According to the concept of historical responsibility, the commitments of individual countries to take action on climate change are distributed based on the relative effects of their past emissions as manifested in present climate change. Brazil presented a comprehensive version of the concept to pre-Kyoto negotiations in 1997. The ‘Brazilian proposal’ originally combined several justice principles; however, following referral to the Subsidiary Body for Scientific and Technological Advice, discussion soon became confined to technical calculations. This case illustrates how disparities in knowledge production and framing can influence the inclusiveness of negotiations. Southern participation in the policy process was restrained due to lack of scientific expertise on the part of Southern countries and due to the non-inclusive biophysical discourse traditionally preferred by Northern policy-makers. The historical responsibility issue became stranded on problems of how to correctly represent physical nature in climate models. This marginalized the original intention that equity should be the guiding principle of the North—South interaction, arguably undercutting a potential angle of approach to advance the climate change negotiations. The article concludes that in the interest of facilitating the North—South dialogue in climate change negotiations, any framing of historical responsibility that excludes equity needs to be redefined. 相似文献
69.
Xolisa Ngwadla 《Climate Policy》2014,14(1):8-16
Equity is a highly contentious but essential area of negotiation, if a stable and effective international climate agreement with broad participation is to be achieved. Three perspectives on the magnitude dimensions of equity are identified that need consideration in the process of formulating an agreement: agreement on a ‘safe’ temperature goal; agreement on the required global effort; and agreement on a fair division of contributions. The opportunities are explored for reconciling these perspectives in an operational framework for equity. Specifically, this means the importance of the adopted a global temperature goal of below 2°C temperature increase by the end of the century. In addition, an initial approach to quantifying adaption costs is suggested, while the importance of arriving at a global mitigation goal is emphasized. It is argued that finance and technology support commensurate with the required global mitigation and adaptation effort is an important element of equity.Policy relevanceThe centrality of equity, in terms of both form and magnitude, will be vital for the design and implementation of a 2015 Agreement that is capable of achieving the objectives of the Convention. Three central areas of debate within global negotiations are identified and discussed: an appropriate temperature goal; global goals for adaptation, mitigation, finance, and technological support; and the division of global effort. The opportunities for reconciling the areas of debate are explored specifically in the context of an Equity Reference Framework, along with suggestions for approaches to quantifying adaptation needs. 相似文献
70.