4,487 research outputs found
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Cloud tracking in cloud-resolving models
In recent years Cloud Resolving Models (CRMs) have become an increasingly important tool for the study of convective phenomena. CRMs should not be regarded as simply providing surrogates for observations; rather
Transfer Matrix Analysis of the Unidirectional Grating-Assisted Codirectional Coupler
The unidirectional grating-assisted codirectional coupler (U-GACC) has recently been proposed. This unique structure permits irreversible coupling between orthogonal waveguide eigenmodes by means of simultaneous modulation of both the real and imaginary parts of the refractive index in the coupling region. Analysis of the U-GACC has until now relied on coupled mode theory, which can be restrictive in its application as a design tool. We analyze the U-GACC by the transfer matrix method, which demonstrates in a simple fashion why the device operates in a unidirectional manner. In addition, we show that for all practical designs, there is a limit to the minimum cross talk between outputs, a phenomenon that has not been previously identified
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Supply chain implications of sustainable design strategies for electronics products
Increasing legislative and consumer pressures on manufacturers to improve sustainability necessitates that manufacturers consider the overall life cycle and not be scope restricted in creating products. Product strategies to improve sustainability have design implications as many of the decisions made during the design stage will then determine the environmental performance of the final product. Coordination across the supply chain is potentially beneficial as products with improved energy efficiency can be better realised. This paper examines traditional product provision and proposes a sustainable product design process using life cycle assessment (LCA) at key points, as these decision points can provide opportunities for environmental improvements of products. Case studies of consumer and industry products in the electronics sector are examined in terms of improving sustainability by reviewing product architecture and technology solutions. This paper proposes methods and analytical models to better understand sustainable design strategies for manufacturing firms and thus aid manufacturers during the earliest stages of product planning to consider alternative product development approaches which are more sustainable
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Sustainable development strategies for product provision and manufacturing approaches
Manufacturing firms are under many pressures both financially and competitive which focus attention on the performance of their manufacturing processes. In this paper the opportunities for improving the environmental impact of products within the constraints of existing manufacturing infrastructure are examined. Approaches which support sustainability in two aspects are proposed, firstly, the provision of products to the users in ways which extend the product life and secondly, manufacturing approaches which reduce resource usage. The provision and manufacture of products in ways that are truly sustainable are inhibited by three issues: firstly, decisions are predominantly made solely from the perspective of the âvendorâ (and do not consider the wider perspective); secondly, that generally the scope of business planning is still rooted in production/manufacturing costs (and not consumption costs) and thirdly, the current performance measures (e.g. KPIs) mainly focus on profitability. The rationale for this conference paper is the argument that there is a need to raise the awareness during the earliest stages of business planning that there may be alternative approaches which are more sustainable. The concepts presented here will underpin further research into performance measures which encompass sustainability and resulting business planning implications
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Design for manufacture and sustainability in new product development
Design for manufacture is well recognised by industry and is about optimising design to aid production. Today there is a significant and growing trend of recognising what happens to a product once its user phase has finished. Post-consumer processes are now an important consideration during the ab-initio stages of design. Rather than a focus limited to design for manufacture or (more recently) design for assembly now the pressure is on for post consumer design. Companies need to do this because legislative pressures are increasing and consumers are becoming ever more aware of, and concerned about, environmental issues. End-of-life processing and design for the environment are therefore areas of growing of interest. This conference paper investigates with industry practitioners their experiences regarding for both the environmental and economic advantages of product life-cycle planning. Legislative pressures and consumer awareness are driving businesses to develop sustainable product design strategies (Jones et al, 2001 p. 27). Changes within the law, to protect our environment, cause companies to pay attention as they begin to affect profitability. The first British Standard to address design for end-of-life processing, and therefore support industry, is BS 8887-1. Over 60 UK manufacturing and design companies that had bought BS 8887-1 contributed to this by being interviewed or providing a written response. The research investigated multiple aspects of sustainable design in practice however, in this conference paper the focus is its application within the design process
'Good figs, bad figs': theologies of differentiation in Jeremiah 21-45
This thesis explores the concept of inner-Judean differentiation in the judgement and salvation
oracles of Jer. 21â45. Specifically, it aims to identity the various 'polarities' of who will and
will not be saved and to explore their underlying rationale. In order to show how these concepts
interact, a synchronic approach is preferred, in which the relevant texts are analysed within their
literary units.Chapter 1 places the differentiation texts of Jer. 21-45 against the background of indiscriminate
judgement preaching in Jer. 1-20. The works of K.-F. Pohlmann, C.R. Seitz and N. Kilpp on
Jeremiah are then reviewed and assessed. It is argued that Pohlmann and Seitz, in particular,
overlook important modes of differentiation within Jer. 21-45.Chapters 2, 3 and 4 form the bulk ofthe thesis. Chapter 2 identifies three polarities in Jer. 21-
24: those who stay in Jerusalem v. those who surrender (21.1-10), Israel's leaders v. its people
(23.1-8), and the exiles in Babylon v. the non-exiles in Jerusalem (24.1-10). The hermeneutical
relationship between these passages is then discussed. Chapter 3 focuses on Jer. 27-29, which
presents two intersecting polarities; that of the exiles v. non-exiles, and that ofprophets v.
people. This configuration is complicated by the additional material in MT 29.16-20. Chapter 4
examines Jer. 37-45, where the mode of differentiation in the oracles to Ebed-Melech and
Baruch reshape the mode of differentiation in Jeremiah's message to the people of Jerusalem and
the remnant of Judah. Chapter 5 briefly describes the message of undifferentiated salvation in
Jer. 30-31.In chapter 6, it is concluded that although inner-Judean differentiation forms a prominent motif
in Jer. 21-45, no one expression of this has the final word. Rather, the juxtaposition of different
or partly similar polarities results in a kaleidoscopic picture, consistent with the book as a whole
and the period in which it was formed. It is also concluded that there is no single rationale for
judgement or salvation; however, the actual experience ofjudgement seems to facilitate the
promise of salvation. The thesis concludes by considering the relevance of the research to the
works of Pohlmann and Seitz
Changes in global agriculture: A framework for diagnosing ecosystem effects and identifying response options
The Forum of European Geological Surveys Geochemistry Task Group 1994-1996 inventory
The Forum of European Geological Surveys (FOREGS) includes representatives from 33 European countries and is responsible for co-ordinating Geological Survey activities in Europe. The FOREGS Geochemistry Task Group was established in 1994 to develop a strategy for the preparation of European geochemical maps following the recommendations of the International Geological Correlation Programme (IGCP) Project 259 âInternational Geochemical Mappingâ (now the International Union of Geological Sciences (IUGS) /International Association of Geochemistry and Cosmochemistry (IAGC) Working Group on Global Geochemical Baselines).
The FOREGS geochemistry programme is aimed at preparing a standardised European geochemical baseline to IGCP-259 standards. The principal aims of this dataset will be for environmental purposes, as a baseline for the assessment of the extent and distribution of contaminated land in the context of variations in the natural geochemical background, but it will also have applications in resource assessment and for the development of policy for the sustainable management of metalliferous mineral and other resources.
The first phase of the programme was the compilation of an inventory of geochemical data based on the results of a questionnaire completed by Geological Surveys and related organisations throughout the FOREGS community. The results show that the sample types which have been used most extensively are stream sediment (26% coverage), surface water (19% coverage) and soil (11% coverage). Stream sediments have been collected using a narrow range of mesh sizes (< 150â< 200 ÎŒm), but soil samples have been collected according to two different conventions: some surveys used a similar mesh size range to that used for stream sediments while others employed the < 1000 or < 2000 ÎŒm fractions traditionally used by soil surveys. Sample densities range from 1 sample per 0.5 km2 to 1 per 3500 km2. Various analytical methods have been used, but most of the available data have been calibrated using international reference materials, and data for the most important of the potentially harmful elements (PHEs) are available for most datasets. Systematic radiometric data are available for only a small proportion of Europe, a situation which compares very unfavourably with that in Australia, North America, the former Soviet Union and many developing countries.
Recommendations are made for increasing the compatibility of geochemical methods between national geochemical surveys as a basis for the preparation of a series of European geochemical maps. The next stage of the FOREGS Geochemistry Task Group will be the collection of the Global Reference Network of samples against which to standardise national datasets according to the methods recommended in the final report of the IGCP 259 programme
The truncated and evolving inner accretion disc of the black hole GX 339-4
The nature of accretion onto stellar mass black holes in the low/hard state
remains unresolved, with some evidence suggesting that the inner accretion disc
is truncated and replaced by a hot flow. However, the detection of relativistic
broadened Fe emission lines, even at relatively low luminosities, seems to
require an accretion disc extending fully to its innermost stable circular
orbit. Modelling such features is however highly susceptible to degeneracies,
which could easily bias any interpretation. We present the first systematic
study of the Fe line region to track how the inner accretion disc evolves in
the low/hard state of the black hole GX 3394. Our four observations display
increased broadening of the Fe line over two magnitudes in luminosity, which we
use to track any variation of the disc inner radius. We find that the disc
extends closer to the black hole at higher luminosities, but is consistent with
being truncated throughout the entire low/hard state, a result which renders
black hole spin estimates inaccurate at these stages of the outburst.
Furthermore, we show that the evolution of our spectral inner disc radius
estimates corresponds very closely to the trend of the break frequency in
Fourier power spectra, supporting the interpretation of a truncated and
evolving disc in the hard state.Comment: Accepted for publication in A&A. Some typos corrected from version
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