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《Journal of Manufacturing Processes》2014,16(2):320-328
Micro and multiscale sheet metal forming processes represent new and attractive solutions to many manufacturing problems. However, evaluating the strains in these products is a difficult endeavor. Larger organizations are utilizing commercially available microscale digital image correlation systems to measure the strains in microscale parts or on macroscale parts with critical microscale features. The cost of these strain measurement systems is preventing smaller research and development organizations from entering this challenging area or they are forgoing the ability to determine strains. The present paper describes the development of a method for creating microscale grids and measuring strains on microscale parts or microscale locations on larger parts. The method developed was able to measure true strains up to 0.618 for square grids that are 127 μm measured from center-to-center. Microscale strains resulting from sheet bulge hydroforming experiments using 11 mm, 5 mm, and 1 mm diameter dies were evaluated and material properties of the sheet metal were estimated based upon the strains measured in conjunction with FEA simulations and compared to analytical solutions and microscale tension tests. The material properties determined using the strains and FEM approach were consistent with the other methods. 相似文献
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The underlying principles of water’s equation of state (ES) and its associated pressure–volume–temperature (PVT) relationship, are employed for the purpose of producing “ultra-high” pressure within the closed volume of a thick-walled metal tube, resulting in a new and innovative hydroforming process. The process, called “Closed-Volume Thermally Activated” (CVTA) Tube Hydroforming, involves conducting a high level of heat through the walls of a thick-walled, metallic, water-containing closed tube. Experimental validation of the concept is presented, and potential applications are discussed. This work represents a break-through in manufacturing technology, which, when further developed, is expected to enable manufacturers to expand significantly their manufacturing capability. 相似文献
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C. Price Y. Yair A. Mugnai K. Lagouvardos M.C. Llasat S. Michaelides U. Dayan S. Dietrich E. Galanti L. Garrote N. Harats D. Katsanos M. Kohn V. Kotroni M. Llasat-Botija B. Lynn L. Mediero E. Morin K. Nicolaides S. Rozalis K. Savvidou B. Ziv 《Environmental Science & Policy》2011,14(7):898-911
The FLASH project was implemented from 2006 to 2010 under the EU FP6 framework. The project focused on using lightning observations to better understand and predict convective storms that result in flash floods. As part of the project 23 case studies of flash floods in the Mediterranean region were examined. For the analysis of these storms lightning data from the ZEUS network were used together with satellite derived rainfall estimates in order to understand the storm development and electrification. In addition, these case studies were simulated using mesoscale meteorological models to better understand the meteorological and synoptic conditions leading up to these intense storms. As part of this project tools for short term predictions (nowcasts) of intense convection across the Mediterranean and Europe, and long term forecasts (a few days) of the likelihood of intense convection were developed. The project also focused on educational outreach through our website http://flashproject.org supplying real time lightning observations, real time experimental nowcasts, forecasts and educational materials. While flash floods and intense thunderstorms cannot be prevented as the climate changes, long-range regional lightning networks can supply valuable data, in real time, for warning end-users and stakeholders of imminent intense rainfall and possible flash floods. 相似文献
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Using information derived from the voluntary system of notification of congenital malformations in England and Wales, the birth prevalence of anencephaly and spina bifida was estimated to have declined by 80 per cent from 31.5 to 6.2 per 10 000 between 1964–1972 and 1985. Over the same period, notified terminations of pregnancy with a suspected fetal central nervous system abnormality increased from less than 1 per cent to 56 per cent of neural tube defect births and central nervous system terminations combined, accounting for 31 per cent of the decline in births. Routinely collected national statistics provide a method for monitoring the impact of screening for open neural tube defects. However because they are incomplete and lack detail an alternative method of monitoring is needed. This paper includes an outline of such a method, together with the results of a pilot study designed to assess the feasibility of monitoring screening in the Oxford Region. 相似文献
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David J. H. Brock 《黑龙江环境通报》1981,1(1):11-16
An analysis is made of alphafetoprotein (AFP) concentrations in 3630 amniotic fluids submitted for prospective prenatal diagnoses over a 7-year period. There were 89 cases of anencephaly, 74 of open spina bifida and 3467 with normal singleton outcomes. The AFP data were expressed in both standard deviations above the mean and multiples of the normal median for individual weeks of gestation. False positive and false negative rates were comparable in the two systems at selected cut-offs. It is concluded that either system may be used in setting action limits for the primary distinction of unaffected pregnancies from those in which an open neural tube defect is present. 相似文献
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Eric S. Marland Kirk Stellar Gregg H. Marland 《Mitigation and Adaptation Strategies for Global Change》2010,15(1):71-91
With an evolving political environment of commitments to limit emissions of greenhouse gases, and of markets to trade in emissions
permits, there is growing scientific, political, and economic need to accurately evaluate carbon (C) stocks and flows—especially
those related to human activities. One component of the global carbon cycle that has been contentious is the stock of carbon
that is physically held in harvested wood products. The carbon stored in wood products has been sometimes overlooked, but
the amount of carbon contained in wood products is not trivial, it is increasing with time, and it is significant to some
Parties. This paper is concerned with accurate treatment of harvested wood products in inventories of CO2 emissions to the atmosphere. The methodologies outlined demonstrate a flexible way to expand current methods beyond the assumption
of a simple, first-order decay to include the use of more accurate and detailed data while retaining the simplicity of simple
formulas. The paper demonstrates that a more accurate representation of decay time can have significant economic implications
in a system where emissions are taxed or emissions permits are traded. The method can be easily applied using only data on
annual production of wood products and two parameters to characterize their expected lifetime. These methods are not specific
to wood products but can be applied to long-lived, carbon-containing products from sources other than wood, e.g. long-lived
petrochemical products. A single unifying approach that is both simple and flexible has the potential to be both more accurate
in its results, more efficient in its implementation, and economically important to some Parties. 相似文献
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New approach to studies of heavy metal redistribution in soil 总被引:7,自引:0,他引:7
F.X. Han A. BaninW.L. Kingery G.B. TriplettL.X. Zhou S.J. ZhengW.X. Ding 《Advances in Environmental Research》2003,8(1):113-120
The bioavailability and mobility of heavy metals in soils is dependent upon redistribution processes between solution and solid phases and among solid-phase components. This paper reviews the definitions and applications of two newly developed parameters, the redistribution index and the reduced partitioning parameter, in quantifying redistribution processes of heavy metals in contaminated soils. The redistribution index depicts the removal/attainment of metal-contaminated soils from/to the fractional distribution pattern characteristic of non-amended soils, while the reduced partitioning parameter quantifies the relative binding intensity of heavy metals in soils. Over time, metal salt-spiked and sludge-amended soils approached the fractional distribution pattern of non-amended soils. The rates of redistribution of metals and their binding intensity in soils were affected by the metal species, loading levels and soil properties. Metals in contaminated soils at low loading levels approach the fractional distribution pattern of non-amended soil more rapidly than those at high loading levels. The sequence order of approach by metals to the fractional distribution pattern of non-amended soil was: Cd>Cu>Ni=Zn>Cr. In both non-amended and contaminated soils, Cr had the highest binding intensity, Cd the lowest, and Cu, Ni and Zn, intermediate values. In addition to our own data, primarily on metal salt-spiked soils, these two indices are also used to evaluate redistribution processes of heavy metals in sewage sludge-amended soils from other published reports. 相似文献
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Rania A. Bekheet Mohamed El Raey Alaa-El-Din Yassin 《Mitigation and Adaptation Strategies for Global Change》2017,22(7):1113-1130
One of the most pressing issues in studying the impacts of sea level rise (SLR) triggered by climate change is understanding the development of the hazard of permanent coastal flooding. The issue persists because available approaches are based on the mapping of the inundated area where they explore the coastal flooding development across terrain elevations, that is—horizontally. In addition, they overlook the existing structures along or in the vicinity of the coastline, which have inherent hydraulic properties that may affect the development of such flooding. The purpose of this study is to develop a novel approach for assessing the development of permanent coastal flooding due to SLR at cross sections along the coastline, that is—vertically, in full consideration of underlying hydraulic properties of the existing coastline. An approach was developed using analogy of existing coastline to a contiguous weir. This approach was named crestline approach and was developed as a four step GIS-based approach that could be applied at any coastal zone. An example application on one of the top ranked cities in the world prone to the SLR threat has been provided to illustrate exactly how to apply the crestline approach. The novelty of this approach lies in its ability to accurately identify the specific locations where coastal flooding will initiate, in full consideration of existing natural/manmade coastal structures. This study is significant for the opportunities it provides to analysts and decision makers to better understand the development of permanent coastal flooding. 相似文献
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The D2-protein is a neuronal membrane protein which has an immunochemically detectable soluble derivative in cerebrospinal fluid. We used rocket-on-line immunoelectrophoresis with an antiserum against rat synaptosomal membranes for demonstration of the human D2-protein in fetal cerebrospinal fluid and in amniotic fluids from pregnancies with fetal neural tube defects. D2 was neither found in normal amniotic fluids nor in cases of amniotic fluids from pregnancies with other malformations. Analysis of D2 in amniotic fluids may thus have a future role in the antenatal diagnosis of fetal neural tube defects. 相似文献
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Life Cycle Assessment (LCA) is a well-known tool for analyzing environmental impacts on a wide perspective with reference to a product system and the related environmental and economic impacts. The need for a novel approach that complements environmental and financial considerations is addressed in this study with the introduction of a new graphical representation: the Environmental Performance Strategy Map. This graphical map allows one to combine the main environmental indicators (footprints) with the additional dimension of cost. The paper defines the Sustainable Environmental Performance Indicator as a single measure for sustainability of a given option. Comparison of different options for strategic decision-making purposes can be enhanced and facilitated by the use of this indicator. 相似文献
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H. Thom A. G. M. Campbell V. Farr P. M. Fisher M. H. Hall G. H. Swapp E. S. Gray 《黑龙江环境通报》1985,5(1):15-19
Over the three years period 1980–1982, 18 256 pregnancies in the Grampian Region of N-E Scotland including the islands of Orkney and Shetland were screened for raised levels of maternal serum alpha fetoprotein (MSAFP) in the second trimester. Thirty six cases of fetal open neural tube defect in singletons were detected (18 anencephaly and 18 spina bifida). Four additional cases of open spina bifida were associated with normal MSAFP levels although two of these were detected by amniotic fluid AFP measurement when amniocentesis was carried out because of previous NTD history. A further three cases of open spina bifida and two of anencephaly occurred in unscreened pregnancies. The MSAFP screening programme alone was thus instrumental in reducing the birth incidence of open neural tube defects by 36 out of 45 cases (80 per cent) in singletons. 相似文献
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The chemical signals of solitary and territorial felid species are essential for their intraspecific communication. We studied the selection of plant substrates during the fecal marking behavior of the European wildcat Felis silvestris from September 2008 to June 2009 in a protected area in Northwest Spain. The aim of the study was to examine the selection of plants as signal posts with respect to their physical characteristics. We hypothesized that wildcats deposit their fecal marks on plants with physical characteristics (e.g., size, species, and visual conspicuousness) that enhance the olfactory and visual effectiveness of the signal. Our results indicate that diameter, plant group, visual conspicuousness, and interaction between the diameter and plant group influence the decision of wildcats to deposit their fecal marks on plants. The wildcats chose plants with greater diameters and greater visual conspicuousness as scent-marking posts. Moreover, the wildcats chose woody and herbaceous plants, and certain plant species were marked more frequently than expected at random. Indeed, our results indicate that the fecal marks were not randomly distributed on the plants: the wildcats chose to place their marks on plants with certain physical characteristics that maximized the detectability of the signal by intruders and potential mates, thus facilitating the spatial distribution of the species. 相似文献
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As climate change adaptation is increasingly discussed and becoming a mainstream concept, different types of users are asking themselves if and when they should develop an adaptation strategy, often not knowing where to begin. Climate experts, on the other hand, have access to an enormous amount of data that could be useful to users but often do not know how to translate it into something practical. Both users and experts can be linked through two timescales, the system lifespan and climate vulnerability. While the system lifespan relies on the user’s estimation of his planning timeframe, the climate vulnerability is estimated from climate model projections and observations. We propose a simple tool to relate user and climate expert knowledge by combining the two timescales. To be reliable, the interconnection implies a dialogue to first identify what sensitive climate variable will impact the system and subsequently the extent of the impact. Climate data can then be used to identify, with the use of a simple graph, how sensitive a system is likely to be and help users position themselves about the urgency of adaptation. The concept has been successfully presented and applied to the tourism industry, notably the ski industry, which is showcased in this paper. 相似文献
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Sophie Hallstedt Henrik Ny Karl-Henrik Robèrt Göran Broman 《Journal of Cleaner Production》2010,18(8):703-712
This article aims to explore a new approach to assess company decision systems regarding sustainability-related communication and decision support between senior management and product development levels. The assessment approach was developed in theory and its applicability was directly tested in action research in two small and medium-sized companies and two large companies. The results were validated against experiences made by two management consultancies. Our study indicates that successful companies should: (i) integrate sustainability into business goals and plans, backed up by suitable (ii) internal incentives and disincentives and (iii) decision support tools. Our study also indicates that the new assessment approach can be used as a template to assess the current state of sustainability integration in company decision systems. 相似文献
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Zhi-Fu Mi Yi-Ming Wei Chen-Qi He Hua-Nan Li Xiao-Chen Yuan Hua Liao 《Mitigation and Adaptation Strategies for Global Change》2017,22(1):45-66
The task of mitigating climate change is usually allocated through administrative regions in China. In order to put pressure on regions that perform poorly in mitigating climate changes and highlight regions with best-practice climate policies, this study explored a method to assess regional efforts on climate change mitigation at the sub-national level. A climate change mitigation index (CCMI) was developed with 15 objective indicators, which were divided into four categories, namely, emissions, efficiency, non-fossil energy, and climate policy. The indicators’ current level and recent development were measured for the first three categories. The index was applied to assess China’s provincial performance in climate protection based on the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. Empirical results show that the middle Yangtze River area and southern coastal area perform better than other areas in mitigating climate change. The average performance of the northwest area in China is the worst. In addition, climate change mitigation performance has a negative linear correlation with energy self-sufficiency ratio but does not have a significant linear correlation with social development level. Therefore, regional resource endowments had better be paid much more attention in terms of mitigating climate change because regions with good resource endowments in China tend to perform poorly. 相似文献