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101.
《Education for Chemical Engineers》2014,9(2):e21-e31
Biodiesel fuel production and use has been used as the focal point of a semester-long, project-based introductory engineering course at Rowan University. Students worked in teams to conduct a series of laboratory investigations through which they explored the engineering aspects of biodiesel production and purification, properties characterization, quality control and performance testing. The experiments were designed to be cost–effective and transferrable.The laboratory experiments were conducted within the How People Learn framework. An assessment instrument was used as a pre- and post-evaluation method to assess learning outcomes. Students’ gained significantly in learning outcomes areas related to the application of mathematics, science and engineering principles; designing and conducting experiments; analyzing and interpreting experimental data, and solving engineering problems. 相似文献
102.
The Flemish renewable electricity support system has struggled to address a number of problematic issues in the past. These included excessive profit margins and general malfunctioning of the green certificate market, as well as a lack of qualification of various existing renewable energy technologies. The Flemish government responded to these issues by introducing major reforms in 2013, including “banding” to differentiate the support for various technologies. However, reliable methods for differentiating renewable electricity technologies and calculating support levels have not been sufficiently developed. The main objective of the 2013 reforms was to reduce support costs, but application of German feed-in tariffs on 18 reference technologies has shown that most projects in Flanders continue to receive high levels of support. The 2013 reforms did not succeed in addressing malfunctioning of the green certificate market. On the contrary, the confidence of investors in renewable electricity plants has decreased as the terms of support can be altered retroactively by adjusting remuneration levels and through political interventions. Future adaptations are likely to be made which will further decrease the overall stability and effectiveness of the system. 相似文献
103.
《Energy Policy》2015
This study investigates CO2 emission reduction within the EU resulting from the Emissions Trading Scheme (ETS) up to 2030. This is performed by constructing a baseline scenario without the ETS and assessing the impacts of the ETS, as currently designed. The results indicate that the ETS will start to impact emissions primarily after 2025 due to the prevalence of a sizable allowance surplus. The impact of approved (i.e. back-loading and 2.2% linear reduction factor (LRF)) and proposed (i.e. market stability reserve (MSR)) policy interventions and the inclusion of aviation, could accelerate the exhaustion of surplus and increase emission reductions during the investigated period. However, these measures would be insufficient to restore the scarcity of allowances and the corresponding carbon price before the start of ETS Phase IV, and the effectiveness of EU-internal abatement cannot be guaranteed until 2023. The effectiveness could be further reduced in the case of the economic shocks or the exclusion of international aviation.To restore the scarcity of allowances, other reform options are necessary. This paper extends the reasoning for the early removal of the back-loaded 900 Mtonne allowances by 2020 and broadening the scope of ETS to other sectors with potential high demand for allowances. 相似文献
104.
Beyond Cognitive Framing Processes: Anger Mediates the Effects of Responsibility Framing on the Preference for Punitive Measures 下载免费PDF全文
A new stream of research indicates that framing effects are based on emotional as well as cognitive processes. However, it is not entirely clear whether emotions mediate framing effects and what the moderators of emotional mediation processes are. To address these questions, we conducted an experiment in which the framing of responsibility for a social problem was manipulated (ambivalent vs. high‐responsibility frame). We find that the high‐responsibility frame increased the preference for punitive measures by increasing responsibility beliefs and eliciting anger. Furthermore, we find that trait anger moderates the framing effect on anger and that responsibility beliefs are positively associated with anger intensity. The significance of these findings for framing research and suggestions for future studies are discussed. 相似文献
105.
Automated fabrication techniques are currently largely confined to the production of discrete objects or building elements. To notch up the potential of robotics for architectural design, it is necessary to start to push the limits and experiment at a larger urban scale. Fabio Gramazio and Matthias Kohler are pioneers in this field. Here, with Jan Willmann , they describe the research that they are undertaking as part of the Future Cities Laboratory (FCL) located at the Singapore-ETH Centre for Global Environmental Sustainability (SEC) and ETH Zurich, in which robotic fabrication technologies are employed to realize 1:50 physical models of mixed-use high-rise structures that are unique in their spatial layouts. 相似文献
106.
1990年代后期以来,美国的学术界、政界对于蔓延问题愈加关注.在联邦、州、地方政府各个层级,实施了立体、多样化的以控制蔓延为目的的政策.其中既有资金激励、规划调控、税收和特殊收费等手段的综合运用,也可按照已建成区、在城市化地区以及农业和乡村地区的划分有针对性地进行调控.在政策框架内,存在较成熟的体系能够对政策的效果、效率、公平性、可行性等进行全方位的预测和评价.中国的土地利用集约化政策,在一定程度上可以与美国控制蔓延的政策相参照,以寻求从价值观到技术方法、从政策内容到政策过程的革新. 相似文献
107.
传统基于技术理性的蓝图式总体规划难以适应经济社会快速发展的要求,《重庆市城乡总体规划(2007—2020年)》(2011年修订)探索实践了《城乡规划法》和《城市总体规划修改工作规则》规定的修改程序。增强总体规划的适应性,需要建立动态完善总体规划的机制、加强多层级多部门的协调合作、空间与政策并重,加强对城市宏观发展趋势的把握。 相似文献
108.
Brian Cheung Ning Cao David S.-K. Ting 《The International journal of environmental studies》2013,70(4):566-577
In the near future, the electricity industry is likely to face historically significant changes. The onset of distributed generation, micro and smart grids will change the entire structured industry. An influx of intermittent renewable generators will make traditional grid balancing notably more difficult. The novel concept of underwater compressed air energy storage is a potentially promising solution that may be used to meet these challenges, especially during the current period of electrical infrastructure renewal and modernisation. Early results from a Lake Ontario Pilot Study point to the potential viability of the concept. 相似文献
109.
The environment has been perceived as an international issue, and ways of attaining sustainability are becoming important for countries seeking sustainable development. The international community has been active in developing policy frameworks towards achieving the sustainability, such as an ecological modernization approach and environment assessment. Developing countries deserve special attention in the effort to make sustainability an operative criterion in their development activities. Given the difficulties that developing countries are facing, their perceptions of the concept and principles of sustainability differ in various contexts from those of developed countries, and the attainment of sustainability is much more difficult. Therefore, the establishment of a global partnership is important for the vision of sustainability to be realized and operationalized in the world. The current stage of economic development in China provides an opportunity to incorporate environmental provisions into the national development strategies from a relatively early stage, rather than attempt retrofit to strategies. However, at present China's policy initiatives expressed in its Agenda 21 remains only a visionary concept. A comprehensive policy framework and realistic implementation measures are needed. The environmental impacts of the construction industry are extensive, particularly in developing countries. However, as in many developing countries, China's sustainable construction is still at its primary stage and current practice is unsatisfactory. 相似文献
110.
Robert Lowe 《Building Research & Information》2013,41(3):159-175
The magnitude and implications for the construction industry of reductions in carbon dioxide emissions that will ultimately be required globally and in industrialized countries are critically examined. As a result of the problem of climate change, these reductions are found to be in the region of 80–90% by 2050- much larger than those presently under discussion in national and global political fora. The technological feasibility of buildings with low energy requirements and low carbon emissions suggests that existing technology is capable of delivering reductions in this range. Unfortunately, the progress that is being made at the cutting edge is, with very few exceptions, not carried over into building stocks as a whole. Regulatory, fiscal and market-based policy and strategy mechanisms for improving the performance both of new build and the existing stock are critically examined. The achievement of meaningful reductions will require a coordinated and strategic approach, which makes use of the complementarity between these mechanisms. Regulation alone, in the absence of clear and consistent price signals provided through mechanisms such as carbon taxation, is unlikely to deliver the reductions in carbon emissions that will be needed to stabilize the global atmosphere and climate. L'ampleur et les implications pour l'industrie de construction des réductions des émissions de dioxyde de carbone qui seront généralement exigées en fin de compte font l'objet d'un examen critque dans les pays industrialisés. Suite au problème des changements de climat, on a trouvé qu'en 2050 ces réductions d'émissions devraient se situer dans une zone de 80 à 90 % - c'est à dire, beaucoup plus grands que celle qu'on trouve dans les discussions et symposiums politiques nationaux et mondiaux. La faisabilité technologique de constructions nécessitant peu d'énergie et à faible émission de carbone suggére que la technologie actuelle est capable d'apporter des solutions à ces réductions. Malheureusement, à de rares exceptions prés, les progrés qui sont faits dans ces domaines de pointe ne sont pas appliqués dans leur totalité au secteur du bâtiment. La politique coordinatrice et fiscale, basée sur le marché ainsi que les mécanismes stratégiques visant à améliorer les performances concernant aussi bien les nouvelles constructions que celles existantes, sont examinés d'une façon critique. L'obtention de réductions significatives exigera une approche coordonnée et stratégique mettant en oeuvre ces deux mécanismes complémentaires. La seule réglementation, en l'absence d'arguments de prix clairs et cohérents comme par exemple la taxation sur l'oxyde de carbone, ne va vraisemblablement pas entrâner les réductions d'émissions de gaz carbonique qui seraient nécessaires afin de stabilizer l'atmosphère et le climat au niveau mondial. 相似文献