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91.
Bioeconomy has gained political momentum since 2012 when the European Commission adopted the strategy “Innovating for Sustainable Growth: A Bioeconomy for Europe”. Assessing the environmental performance of different bioeconomy value chains (divided in three pillars: food and feed, bio-based products and bioenergy) is key to facilitate solid and evidence-based policy making. The objectives of this work were: (1) to map and analyse accessible LCA data related to bioeconomy value chains in order to identify knowledge gaps; (2) provide a more robust and complete picture of the environmental performance of three bioeconomy value chains (i.e. one per each bioeconomy pillar). This analysis reveals that apart from few products (such as liquid biofuels, some biopolymers and food crops) the environmental assessment of bioeconomy value chains is still incipient and limited to few indicators (e.g. Global Warming Potential and energy efficiency). In this study, a harmonised procedure – the Product Environmental Footprint (PEF), which includes fourteen impact categories – is used to estimate the environmental performance of three exemplary case studies which are inter-related due to the use of sugar as feedstock: sugar (food and feed), bio-based ethanol (bioenergy) and polyhydroxyalkanoates (bio-based product). Results highlight the strong need for methodological harmonisation and coherence for LCA of bioeconomy value chains.  相似文献   
92.
Gas turbine blades are exposed to high-temperature degradation environments due to flames and mechanical loads as a results of high-speed rotation during operation. In addition, blades are exposed to thermo-mechanical fatigue due to frequent start and shutdown. Therefore, it is necessary to evaluate the lifetime of blade materials.In this study, the TMF life of a Ni-base superalloy applied to gas turbine blade was predicted based on LCF and TMF test results. The LCF tests were conducted under various strain ranges based on gas turbine operating conditions. In addition, IP (in-phase) and OP (out of-phase) TMF tests were conducted under various strain ranges.Finally, a fatigue life prediction model was drawn from the LCF and TMF test results. The correlation between the LCF and TMF test results was also evaluated with respect to fatigue life.  相似文献   
93.
Minimum efficiency performance standards (MEPS) are an important policy instrument to raise the efficiency of products. In most schemes the concept of life cycle costs (LCC) is used to guide setting the MEPS levels. Although a large body of literature shows that product cost is decreasing with increasing cumulative production, the experience curve, this is currently not used for setting MEPS. This article shows how to integrate the concept of the experience curve into LCC calculations for setting MEPS in the European Union and applies this to household laundry driers, refrigerator-freezers and televisions. The results indicate that for driers and refrigerator-freezers at least twice the energy savings compared to the current approach can be achieved. These products also show that energy label classes can successfully be used for setting MEPS. For televisions an experience curve is provided, showing a learning rate of 29%. However, television prices do not show a relation with energy efficiency but are to a large extent determined by the time the product is placed on the market. This suggests to policy makers that for televisions and other products with a short (re)design and market cycle timing is more important than the MEPS levels itself.  相似文献   
94.
A model for multiaxial high-cycle fatigue life evaluation of notched structural components is proposed, which considers the impact of the stress field on fatigue life by utilizing the Theory of Critical Distances (TCD) and Finite Element Method (FEM). The maximum shear stress range plane is defined as the critical plane, and the damage parameters are the maximum effective shear stress amplitude and the maximum effective normal stress, which are obtained by averaging the stress in the hemisphere volume around the maximum stress point. To validate the accuracy of the model, multiaxial fatigue tests are carried out for both smooth and notched specimens of Aluminum–Silicon alloy. The results indicate that the evaluated life and experimental life have a good agreement.  相似文献   
95.
Though condensed between the stages of design and completion, the conventional process of designing a building is time consuming, involving various stakeholders, planning processes and a wide team of consultants and contractors. What happens, though, if the time period of an architect's involvement is expanded? How might a more process-orientated approach shift the role of the architect? Tobias Armborst, Daniel D'Oca and Georgeen Theodore , principals of Interboro Partners in New York, describe how they have developed projects that have sought opportunities in expanding the timescale and remit of traditional practice.  相似文献   
96.
The explosion of the palm oil industry in recent decades has transformed vast swathes of the Malaysian and Indonesian countryside. Milica Topalovic , Assistant Professor of Architecture and Territorial Planning at ETH Zurich, asserts that the resulting agro-industrial landscapes challenge the very concept of what is rural, and considers how such areas should be conceptualised.  相似文献   
97.
This study explores how two different cellulosic ethanol production system configurations (distributed versus centralized processing) affect some aspects of the economic and environmental performance of cellulosic ethanol, measured as minimum ethanol selling price (MESP) and various environmental impact categories. The eco-efficiency indicator, which simultaneously accounts for economic and environmental features, is also calculated. The centralized configuration offers better economic performance for small-scale biorefineries, while the distributed configuration is economically superior for large-scale biorefineries. The MESP of the centralized configuration declines with increased biorefinery size up to a point and then rises due to the cost of trucking biomass to the biorefinery. In contrast, the MESP in the distributed configuration continuously declines with increasing biorefinery size due to the lower costs of railroad transportation and the greater economies of scale achieved at much larger biorefinery sizes, including biorefineries that reach the size of an average oil refinery—about 30,000 tons per day of feedstock. The centralized system yields lower environmental impacts for most impact categories than does the distributed system regardless of the biorefinery size. Eco-efficiency analysis shows that the centralized configuration is more sustainable for small-scale biorefineries, while the distributed configuration with railroad transport is more sustainable for large-scale biorefineries. Compared with gasoline from petroleum, cellulosic ethanol fuel offers sustainability advantages for the following environmental impact categories: fossil energy consumption, global warming, human health impacts by particulate matter, ozone layer depletion, ecotoxicity, human health cancer, and human health non-cancer, depending somewhat on the biorefinery sizes and the system configurations.  相似文献   
98.
Mislabelling of seafood products has been documented in numerous countries for over three-quarters of a century. With a trend towards increased consumption of seafood, the informed consumer demands accurately labelled products that provide full disclosure of composition. DNA barcoding can be used to accurately identify a seafood product to species based on its genetic signature, and so provides a means to test the authenticity and accuracy of seafood labelling. This can be especially useful for products such as fillets which have few or no unambiguous identifying characters, and can easily be mislabelled. We investigated labelling accuracy in seafood retailers in Tasmania, Australia. Thirty-eight seafood products were obtained from seafood retailers, sequenced for the barcoding gene region cytochrome oxidase subunit 1(CO1), and subsequently identified to species level by querying GenBank and Barcode of Life Data Systems (BOLD) DNA sequence records. Results were compared with standard fish names (SFN) prescribed under the Australian Fish Names Standard (AFNS) and FishBase. Of the 38 samples, none were deemed to have been mislabelled under Australian regulation, although in some cases naming discrepancies and ambiguity may cause confusion for some consumers. Our work, while reflecting high standards in Tasmanian seafood, highlights the need for mandatory standard labelling across all seafood products so as to eliminate any possible misrepresentation.  相似文献   
99.
Various curve fitting models, including the Arrhenius stress model, inverse power law model, and Eyring model have been used to model the load (stress) – life relationship to aid in planning accelerated life tests; that is, the relationship between the mean of the sample lifetimes and the testing stress level. The load-life relationship is a one-to-one relationship: one mean of the sample lifetimes corresponds to one testing stress level. However, due to the random uncertainties existing in the testing stress, the relationship should be a many-to-many relationship rather than one testing stress corresponding one mean lifetime of the tested product. Based on the one-to-one relationship of the mean of the sample lifetimes to the testing stress level, a many-to-many relationship can be derived using the reasoning method presented in this paper. The reasoning method is constructed as ‘If X, then Y.’ X is termed the rule antecedent, and Y is called the rule consequent. They are constructed with the stress values and the sample lifetimes, respectively, based on the cloud model, which represents random uncertainty and fuzzy uncertainty. The reasoning method presented is called the multi-rule-based cloud reasoner, which can refine the one-to-one relationship established by models such as the Arrhenius stress model to a many-to-many relationship. In the case study, the multi-rule-based cloud reasoner was applied to a thermal stress accelerated life test of ammunition fuses. The results from the multi-rule-based cloud reasoner were compared with the estimation results from a normal cloud generator under a stress level of 20 °C. The results showed that the many-to-many relationship between the uncertain stress level and the means of the sample lifetimes was derived by the multi-rule-based cloud reasoner.  相似文献   
100.
Felicity D Scott , Associate Professor of Architecture at Columbia University Graduate School of Architecture, Planning and Preservation (GSAPP), describes here the instant city events of the early 1970s. These foreshadowed current global village media practices in what now seems a quaintly material manner: communication between sites involved the physical mailing of videotapes and ‘wire photos’ through the postal service. The sites themselves – in the US and elsewhere – were transformed into ‘instant cities’ through the erection of physical geodesic domes, teepees and inflatables in seas of mud. The true antecedents of today's instant networking, these pioneers embraced the newest technology available at the time and the most innovative forms of temporary architecture.  相似文献   
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