We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
A reference process should consider to the needs and behaviours of the process users, as well as all relevant restrictions and boundary conditions within the company and its environment. Therefore, this contribution provides a method to synthesize relevant requirements on reference processes and supports the consideration of these requirements during the design of a new, company-specific reference process based on meta-models. The developed method was used to design a reference process for automotive predevelopment projects and its applicability and usefulness was evaluated successfully.
Models of products and design processes are key to interacting with engineering designs and managing the processes by which they are developed. In practice, companies maintain networks of many interrelated models which need to be synthesised in the minds of their users when considering issues that cut across them. This article considers how information from product and design process models can be integrated with a view to help manage these complex interrelationships. A framework highlighting key issues surrounding model integration is introduced and terminology for describing these issues is developed. To illustrate the framework and terminology, selected modelling approaches that integrate product and process information are discussed and organised according to their levels and forms of integration. Opportunities for further work to advance integrated modelling in engineering design research and practice are discussed.
A considerable expansion of biogas production in Germany, paralleled by a strong increase in maize acreage, has caused growing concern that greenhouse gas (GHG) emissions during crop substrate production might counteract the GHG emission saving potential. Based on a 2-year field trial, a GHG balance was conducted to evaluate the mitigation potential of regionally adapted cropping systems (continuous maize, maize-wheat-Italian ryegrass, perennial ryegrass ley), depending on nitrogen (N) level and N type. Considering the whole production chain, all cropping systems investigated contributed to the mitigation of GHG emissions (6·7–13·3 t CO2 eq/ha), with continuous maize revealing a carbon dioxide (CO2) saving potential of 55–61% compared with a fossil energy mix reference system. The current sustainability thresholds in terms of CO2 savings set by the EU Renewable Energy Directive could be met by all cropping systems (48–76%). Emissions from crop production had the largest impact on the mitigation effect (⩾50%) unless the biogas residue storage was not covered. The comparison of N fertilizer types showed less pronounced differences in GHG mitigation potential, whereas considerable site effects were observed.
An expression for the stopping power is derived in the quantum T-matrix approximation. The transport cross sections needed for a numerical evaluation are calculated using a scattering phase-shift analysis. Numerical results are given for the stopping power of an electron beam running into an electron gas. The temperature and density dependencies of the stopping power are discussed. Finally, dynamical screening is included in the weak coupling limit according to a kinetic equation proposed by H.A. Gould and H.E. DeWitt.
The ambulatory prognosis of children with cerebral palsy (CP) remains a major issue for both their parents and the professionals concerned with their management. The question most frequently asked by the parents is: Will my child walk? Several studies have examined the prognostic criteria for ambulation in children with CP.
The relaxation of two-temperature electron–ion systems is investigated. We apply a quantum kinetic approach which is suitable to treat strong electron–ion coupling and avoids any ad hoc cut-off procedures. A comparison with the usual Landau–Spitzer formula gives good agreement for Coulomb logarithms larger than three, whereas larger relaxation rates were found for strongly coupled plasmas. It is shown that the Landau–Spitzer theory can be greatly improved considering hyperbolic orbits. Numerical results for the energy transfer rates and the temporal behavior of the electron temperature are shown.
An instrument equipped with total electron yield detectors was designed and constructed for in situ X-ray absorption spectroscopy (XAS) investigations in the soft X-ray range (100 eV ≤ hν ≤ 1000 eV) at elevated pressures (mbar range) and sample temperatures (T ≤ 1000 K) [1]. This allows, for the first time, XAS studies in a surface-sensitive mode of the light elements (Z = 3-15). Furthermore, the gas phase XAS and the surface-related XAS of the solid state phase can be collected simultaneously in order to correlate the gas/solid reaction rate with the surface electronic structure under working conditions in a flow-through mode.
The novel experimental tool represents a contribution to the experimental overcoming of the “pressure gap” in material science. In this work examples are presented belonging to the field of heterogeneous catalysis [2-4] and to the reactivity of diamond surfaces [5]. Additionally, prospects for in situ studies in material science will be given.