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In this paper we discuss the performance of different profiles of VDSL2 systems in a frequency range up to 12 MHz (bandplan 998 and 997, corresponding to the European region) using two different noise scenarios: VDSL2 Mix and VDSL2 only. The use of different power levels at the downstream is evaluated in these scenarios and it is found that there is no need to use maximum power. As operators are commonly interested to achieve higher data rates, we have selected profile 12a as the most suitable when dealing with frequencies up to 12MHz while consuming 4 times less power at the downstream than profile 8b and leading to similar performance in the scenarios herein described. The impact of using different cables has been evaluated for both the downstream and upstream direction. An analysis on boosted and non-boosted masks is also provided. A method to evaluate the upstream performance per band has been used in order to obtain the contribution of each upstream band versus the loop length. With this approach and keeping in mind the dependency of the cable when evaluating performance (e.g. TP150 0.5mm cable), it has been shown that US2 dies out after 700m, US1 after 1600m and USO provides more or less a constant performance contribution in the VDSL2 only scenario for band-plan 998. The same behavior for these upstream bands but in different ranges is expected for other type of cables (also for other bandplans, i.e. 997, which is presented in annex B). © 2007 IEEE.

The International Organization for standardization (ISO), Technical Committee 163 "Thermal Performance and Energy Use in the Built Environment" (ISO/TC 163) has produced and will produce sets of standards by reference to which performance requirements can be expressed at various levels, from materials to complete buildings. A coherent set of new work items concerning the energy performance of buildings has been launched in April 2007 which are briefly presented in this paper.

Polymers with a small amount of dye blended in offer an attractive possibility to change the color of the emitted light by changing the dye. We present ab initio calculations within density-functional theory of the HOMO/ LUMO energies for dipyrrolomethane dyes, polyphenylenevinylene and polyfluorene. Special attention is paid to the trends in these energies with variation of the sidegroups of the dyes as observed in cyclic-voltammetry measurements. From the energy-level alignments between dye and polymer we can understand and predict electron and hole trapping, crucial processes for the functioning of light-emitting devices based on these blends.

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Methodologies are described for calculating critical loads of persistent organic pollutants (POPs) for soils and surface waters. The various aspects which are discussed, are: environmental quality criteria, calculation methods, input data and the various sources of uncertainty. The calculation methods described are based on the concept of equilibrium partitioning between dissolved and adsorbed phases in soil, surface water and sediment compartments in a steady-state situation.

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The European Commission has mandated CEN to produce a set of standards to support Member States for the national implementation of the EPBD. This paper focuses on one of these standards, EN ISO 13790, "Energy performance of buildings - Calculation of energy use for space heating and cooling". It describes the history of this standard which started with a simplified calculation of the energy use for heating of residential buildings only. It describes the current methodology, inclusing heating and cooling, also for non-residential buildings and the 'level playing field' for both simple and detailed methods. The paper also discusses the issues involving the implementation of the methods in the EU Member States and the prospects for the future.

Within the EU DGXII R&D Programme JOULE a project, called REVIS. started in 1998 and will be completed within 2.5 years, with the objective to develop detailed daylight product information of novel products of glazings and solar shading devices. This involves a test procedure, definition of product daylight quality indices (on potential to avoid glare, to redirect daylight for better distribution and to view through) and a database and software tool for the organisation and calculation of these properties. This paper presents the objectives, method of approach and the expected results of the project

Background: Back pain (including neck pain) is one of the most prevalent health problems for which physicians are consulted. Back pain can decrease the quality of life considerably during a great part of the lives of those who suffer from it. At the same time it has an enormous economic impact, mainly through sickness absence and long-term disability. The objective of this paper is to compare the incidence of occupational disability as a result of back and neck pain in 1980-1985 to 1999-2000 and to explain the findings. Methods: A descriptive study was performed at population level of changes in incidence of occupational disability as a result of back and neck pain. Statistics from the National Institute of Social Insurance in the Netherlands are used to calculate age and gender specific incidence rates for back pain diagnoses based on the ICD-classification. Incidence rate ratios stratified according to gender and adjusted for age were calculated to indicate changes over time. Results: The incidence of occupational disability as a result of back pain decreased significantly by 37% (95% CI 37%-38%) in men and with 21% (95% CI 20%-24%) in women, after adjustment for age. For overall occupational disability as a result of all diagnoses this was 18% (95% CI 18%-19%) and 34% (95% CI 33%-35%) respectively. Changes were not homogeneous over diagnostic subcategories and age groups. Spondylosis decreased most in men by 59% (95% CI 57%-61%). The incidence of non-specific back pain and neck pain increased most by 196% (95% CI 164%-215%). Post-laminectomy syndrome increased over all age categories both for men (85%, 95% CI 61%-113%) and women (113%, 95% CI 65%-179%). Conclusion: The decrease in occupational disability as a result of back pain was larger than the decrease in occupational disability over all diagnoses. However, time trends were not homogeneous over age-, nor over sex- nor back pain categories. Most of this decrease was due to general changes such as legal and economic changes. One of several additional explanations for a decrease is the changed view on management of back pain. © 2006 Steenstra et al; licensee BioMed Central Ltd.

Standardization of emission calculation is progressing swiftly in order to support the improvement of the sustainability of transport chains. Using the GLEC Framework v1.0 as a starting point, this research maps out, which further gaps need to be addressed for ensuring seamless coverage at a meaningful accuracy of such a calculation. The analysis is based on a desk research complemented by considerations and feedback received in the context of real-life test cases of the GLEC Framework. The paper closes with an outlook on requirements towards an eco-label related to the emission calculation standardization.

Carbon footprinting is regarded as one means of enhancing transparency on where greenhouse gas (GHG) emissions 17 are produced within a transport chain and, thus, limiting the emissions and improving the efficiency of transport and transhipment, on both the demand and supply sides of the market. In order to meet global GHG reduction targets and to realize sustainable transport chains, standardization of emissions calculation is progressing swiftly. One of the core requirements in next steps of the standardization efforts is the harmonization of level of detail of the various transport modes. In particular logistics hubs have been identified as relevant for such a development and whereas developments for transport modes such as rail, road, air or water are pursued by industry representatives and their organizations, logistics hubs have no organization which is intrinsically motivated to further develop an emission calculation approach. Research can deliver an important and valuable contribution here. Therefore, based on extensive empirical research in the form of questionnaires and real-life examples of emissions calculation, this paper describes motivations and barriers currently experienced by shippers and logistics service providers when computing emissions. Possible approaches to overcoming these barriers and contributing to the further improvement of the level of maturity of emissions calculation of logistics hubs are described and discussed. The paper closes with an outlook on further requirements toward transport chain emissions calculation standardization developments.

The European Commission has set as a target a reduction of 60% in transport greenhouse gas emissions by 2050 [EC 11]. This includes freight transport emissions, which present a particular challenge due to the forecast increase in goods transport linked to future economic growth, the current trend of lengthening supply chains and the global nature of these supply chains. A wide range of methodologies and tools are available for calculation of the carbon footprint of freight transport, based on varying emissions data, routing and allocation assumptions and conflicts between actual and assumed vehicle loading performance. In spite of recent developments such as the publication of a European standard EN 16258 "Methodology for calculation and declaration of energy consumption and GHG emissions of transport services (freight and passengers)", there is a clear demand from industry, for harmonization of calculation methods applicable along the supply chain, across various modes, and at a global level. The COFRET project is working to support this process using real-life case study supply chains. © ISTE Ltd 2016. All rights reserved.

Adding a carbon capture plant to a power plant reduces the efficiency of said power plant. In order to keep this drop in efficiency as small as possible, several optimisation studies are performed in the OCTAVIUS project. Based on the work of the European Benchmarking Task Force-EBTF within the CESAR, CAESAR, and DECARBit projects, two reference power plants are modelled in Ebsilon®Professional. The first is an 800 MWe coal case, the second a 430 MWe natural gas combined cycle (NGCC) case. For each power plant two separate capture plants are considered: one using 30 wt% MEA as solvent system, the other with CESAR1, a mixture of AMP and PZ as solvent system. This results in four different reference cases which are optimized by varying different process parameters and evaluating process modifications. In a second step, the integration of the capture plant into the power plant is evaluated. This is important especially for the coal fired power plant, where integration of waste heat from the capture plant or the CO2 compressor intercoolers can lead to a significant increase in overall efficiency. The configuration of intercoolers for the CO2 compressor is adapted to achieve the highest overall efficiency. For the natural gas combined cycle plant, integration is not that beneficial, since there is no heat sink available in the water steam cycle. In the end, the cost of electricity and cost of CO2 avoided is calculated for all four cases. While the CESAR1 solvent system in a conventional absorber-stripper scheme is less costly (almost 17%) than the MEA solvent system in a process with Lean Vapour Compression for the coal cases, the result is the opposite for the two NGCC cases though the difference is not substantial.

A series of resonators alongside a road or railway can be used to diffract noise upwards to create a zone of noise reduction behind the elements. The company 4Silence developed the so-called Whisstone, a concrete block with 18 resonators of different depths designed to operate in a broad frequency range. Several measurements at short distance, up to 15 meters, have proven that a noise reduction up to 4 dB(A) can be achieved. To determine the noise reduction at long distances calculations are necessary, due to the uncertainties of ground and meteorological effects. In this paper a comparison between measurements and numerical results (FEM) at short distance is presented. The positive results of this comparison allow the numerical method to be applied at larger ranges, up to 600 meters, taking a downwind condition into account. To this end the FEM method is coupled to a Green's function parabolic equation method (GFPE). The calculations for long distances show noise reductions up to 5 dB in octave bands and 3 dB(A) for the broadband level. These results can be used to account for the diffracting elements in standard noise calculation models used in practice, such as the Dutch national standard model or Cnossos. © INTER-NOISE 2018 - 47th International Congress and Exposition on Noise Control Engineering: Impact of Noise Control Engineering. All rights reserved.

Objective. To determine the cut-off values for the body-mass index (BMI) for underweight and serious underweight in children up to 18 years of age based on the Dutch growth standards of 1980, and to determine the prevalence of underweight and serious underweight in the 1997 Dutch growth-study figures. Design. Secondary data analysis. Method. Cut-off values for underweight were determined by first calculating the percentage of 18-years old with a BMI < 18.5 kg/m2 in 1980, followed by a calculation of the BMI at younger ages under which the same percentage fell. Serious underweight in 18-year olds was defined as a BMI < 17.0 kg/m2. Results. Between 1980 and 1997 the prevalence of serious underweight increased in children aged between 2 and 6 years from 1.5% to 3.6% and from 2.9% to 3.3%, in boys and girls respectively. In older children (7-18 years) the prevalence decreased from 1.5% to 1.4% for boys and from 2.9% to 1.7% for girls. Conclusion. Not only did the median weight of the population increase between 1980 and 1997, but there was also a rise in the variation of the weights at any given age. The latter could reflect more marked health differences.

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Improving the efficiency and sustainability of supply chains is a shared aim of the transport industry, its customers, governments as well as industry organisations. To optimize supply chains and for the identification of best practice, standards for their analysis are needed in order to achieve comparable evaluations. This need for an evaluation standard also applies to CO2 emission calculations. This research focuses on the transportation within supply chains and possible approaches towards a global standard for calculating its CO2 emissions. In the recent past, several organisations, national and international, have come forward with possible methods, tools and databases for the calculation of CO2 emissions along supply chains, but almost all of them do not cover the entire transportation chain. Also standards for CO2 emissions of products and production in general do exist but they do not take the particular requirements of transportation into consideration. Therefore a global standard specifically for transportation could not yet be introduced. The EN 16258 standard is the only international standard for emission calculation of transportation in supply chains. It was therefore analyzed as a possible starting point for a global standardization approach. Analysis shows it too contains gaps and ambiguities which render comparisons of supply chains difficult. These gaps of the EN 16258 are analyzed, followed by suggestions for methodological improvements for their closure. The research concludes with an outlook on next steps needed towards a global CO2 calculation standard for transportation within supply chains.

The Severity of Disabilities Scale (SDS) of the ICIDH reflects the degree to which an individual's ability to perform a certain activity is restricted. This paper describes the application of two models from item response theory (IRT), the graded response model and the partial credit model, in order to derive a tentative proposal for a revised SDS. The key ingredient of the approach is to scale existing disability items obtained in different studies on a common scale by exploiting the overlap. Both IRT models are fitted to a linked data set containing items for measuring walking disability. Based on these solutions, a tentative SDS is constructed. The paper concludes with a discussion of the implications, limitations and advantages of the approach. Copyright © 2001 John Wiley & Sons, Ltd.

Multiblock or multiset methods are starting to be used in chemistry and biology to study complex data sets. In chemometrics, sequential multiblock methods are popular; that is, methods that calculate one component at a time and use deflation for finding the next component. In this paper a framework is provided for sequential multiblock methods, including hierarchical PCA (HPCA; two versions), consensus PCA (CPCA; two versions) and generalized PCA (GPCA). Properties of the methods are derived and characteristics of the methods are discussed. All this is illustrated with a real five-block example from chromatography. The only methods with clear optimization criteria are GPCA and one version of CPCA. Of these, GPCA is shown to give inferior results compared with CPCA. Copyright © 2003 John Wiley & Sons, Ltd.