13 research outputs found
The composition of suspended particulate matter during floodings of the river Meuse
Since the Industrial Revolution, mankind has disturbed the natural functioning of river floodplains by a high input of contaminants in the environment. Riverine suspended matter is the most important source for elevated levels of contaminants in floodplain areas. Previous research mainly focused on processes affecting the distribution of contaminants on the floodplain areas themselves, while the influence of the ultimate polluting source, river suspended matter, is poorly understood. Only minor knowledge is available on the temporal and spatial variability of contaminants in suspended matter. This research focuses on the variability in contamination degree of both suspended matter and floodplain sediment for the Dutch part of the river Meuse
Developments in European Ecodesign Policy and the Prospects for Design for Sustainable Practices
European ecodesign policy is currently bringing material resource efficiency into focus. This paper explores how and to what extent policy addresses sustainable consumption-related issues, and what the consequences may be for the future role of design in supporting sustainable everyday consumption. How will policy help and hinder designers and others in creating change? The paper focuses on the prospects for practice-oriented design, which sees resource consumption as happening in and for the sake of social practices. It first introduces design for sustainable practices as currently explored in academia, highlighting features that distinguish it from ecodesign. Secondly, it turns to policy to describe and assess relevant instruments and envisaged changes. Based on that, and informed by practice theory and literature on the impact of policy on innovation, it discusses the potential impact of ecodesign policy on the prospects for design for sustainable practices. Finally, the paper turns the question around and asks what a practice-oriented policy might look like.Design EngineeringIndustrial Design Engineerin
Propagation of a cadmium spill through an impounded river system
In this paper, the influence of impoundments (sluices, weirs, etc.) and stream components (tributaries, river branches, associated canals) on the metal content in water and suspended particulate matter (SPM) in the Dutch part of the River Meuse is assessed using the decrease in the cadmium content of the particulate and dissolved phase during the transport of a distinct cadmium spill through the river. This anthropogenic spill lasted from July 2005 to June 2006 and is documented by the weekly monitoring results of the Meuse in Eijsden at the Belgian-Dutch border. The monitoring data indicate that cadmium was discharged as a dissolved phase. Redistribution of water towards canals is the cause that during low flow conditions only a limited amount of water with an Eijsden geochemical signature arrives in Keizersveer (near the mouth of the river). During such periods various tributaries and groundwater have significant contributions to the discharge measured in Keizersveer. The monthly variations of cadmium concentrations in total water and SPM, upstream and downstream of the series of impoundments are calculated for the period 1993-2004. Next, the transfer of the cadmium through the impounded part of the river is determined based on the monitoring results obtained in the stations in between and downstream from the impoundments. Finally, possible lag effects of the cadmium spill are quantified using monitoring data obtained in 2006 and 2007. It is concluded that it takes about six months before the cadmium spill is detected in the SPM at the monitoring station of Keizersveer. Leaching of cadmium from the sediment to the surface water may result in high dissolved cadmium concentrations. For a better understanding of the processes in the river system it is essential that the SPM monitoring frequency in river sections downstream of Eijsden is increased, starting with the Keizersveer station. A better system understanding is important in order to define appropriate measures to meet the goals of the Water Framework Directive concerning the chemical status of the Meuse River
Report of meeting on measurement of suspended solids in the Meuse
On June 19/20, 2007 a visit was paid to a suspended particulate matter (SPM) sampling and monitoring site in the Ourthe river (LiĂšge region), between the confluence with the Vesdre river and the mouth of the Ourthe in the Meuse river. The next day, a workshop was organised in which backgrounds, methods and procedures for SPM sampling and monitoring were discussed. Results of measuring SPM quantity and quality in the Meuse river basin were presented. The discussions were focused on the implementation of this matrix in WFD instigated monitoring programs. The workshop was very successful, with animated discussions
Universitair vastgoed als sturingsmiddel in onderwijs en onderzoek
Sinds 2010 is Karel Luyben rector magnificus van de Technische Universiteit Delft. Deze universiteit staat nationaal en internationaal hoog aangeschreven en heeft grote ambities voor zowel onderwijs als onderzoek. De Delftse campus biedt ruimte aan zoân 18.000 studenten en 4.500 medewerkers. Zijn er specifieke kenmerken van een campus aan te wijzen die ervoor zorgen dat studenten en medewerkers er kunnen excelleren? In 2011 publiceerde Alexandra den Heijer haar promotieonderzoek âManaging the University Campusâ. We vroegen de rector magnificus naar zijn persoonlijke visie op wat een campus tot een goede campus maakt. Naast een enthousiaste manager en wetenschapper blijkt Luyben ook buitengewoon âkunstâminnend en mengt hij zich graag binnen alle gelederen en lagen van de TU Delft-gemeenschap. Centraal in zijn visie staat strategisch sturen op verbindingen binnen de campus, met de stad Delft en met andere kenniscentra, nationaal en internationaal.Real Estate and Housin
Huisvesting als middel tot sociaal-economische vitaliteit
Interview met Alexander Rinnooy Kan.Real Estate Managemen
The influence of plants on productivity: A critical assessment of research findings and test methods
PurposeThis paper aims to review available research into the impact of plants on people and labour productivity in order to test a number of hypotheses and the reliability and validity of âevidence basedâ statements.MethodologyAn extended literature review has been conducted of research concerning the potential impacts of plants on people and labour productivity. In order to be able to compare the findings of different researchers, an analysis has been made of similarities and dissimilarities with regard to the research context, starting-points and test methods.FindingsThe paper identifies a lack of precise descriptions of the research design and poor comparability between different research with regard to the characteristics of the plant, test persons, test procedures, surrounding conditions and contents of the reports. Although we may conclude that plants can have a positive impact on the productivity of human beings, it is remarkable that in research reports and research papers the properties of the plant itself are only mentioned by exception. The condition of the plant - whether it is healthy or not â is not described at all.LimitationsâOnlyâ 17 studies and underlying papers were investigated and no new research has been conducted with the proposed improvements. Practical implications The findings can be used by managers to legitimate investments in plants and by researchers to improve (the comparability of) research into plants.OriginalityIn addition to the review of the impact of plants on different types of productivity a vision is presented about the impact of the vitality of plants. Furthermore recommendations are given on how to cope with the methodological problem of poor comparability of research.Accepted Author ManuscriptReal Estate Managemen
InP-based spotsize converter for integration with switching devices
We have designed and fabricated an InGaAsP-InP based spotsize converter (SSC), which is compatible with the waveguide structure used in monolithic integrated ADM's and OXC's. In a first experiment, a total coupling loss to a cleaved fiber of 4.2 dB for TE and 3.9 dB for TM was realized with a 1.5 mm-long SSC. The 1-dB alignment tolerances improved from 0.75 mu m to 2.4 and 2.2 mu m for the horizontal and vertical direction, respectivel
Environmental sizing of smartphone batteries
Smartphone use has increased at a phenomenal pace worldwide. In 2011 more smartphones have been sold than desktop pcâs, notebooks, netbooks and tablets together. The total worldwide smartphone sales reached 472 million units in 2011, and 149 million of them were sold in the fourth quarter of 2011. The smartphone is, like almost every other mobile device, powered by batteries, limited in size and therefore capacity, which makes energy management paramount. While global demand and use of mobile devices continuously expands, the energy density of smartphone batteries has grown at an insignificant rate, but the use period still decreases because of high loads and big screens. In this paper we have studied the power breakdown of five smartphones on sale in 2011. We have defined three different user profiles for âheavyâ, âmoderateâ and âlightâ users and we can state that theoretically it is sensible to re-size the battery based on the user profile. While keeping the user period acceptable we can decrease the battery capacity for moderate and light users with 25%, reducing the worldwide energy needed to product smartphone batteries with 2.1 to 3.4PJ per year. In practice the aging of the battery will result in a decreasing battery capacity over its life. When taking this into account most batteries comply with the moderate users and only a resizing strategy for the light users is sensible. This will account for only 20% of all users and can result in a worldwide decrease of energy needed for producing the smartphone batteries with 0.5 to 0.9PJ.Design EngineeringIndustrial Design Engineerin
Old contaminated sediments in the Rhine basin during extreme situations
Sediments play an important role in water resources management. In the past, hazardous contaminants from municipal and industrial wastewater effluents and from agriculture were discharged in large quantities into the water bodies and accumulated within the bottom sediments. Today, relatively unpolluted recent sediment surface layers cover older contaminated sediments. Due to increasing water discharges associated with high precipitation and heavy rainfall events (climate change) and land use changes there is an increasing risk of the resuspension of old contaminated sediment layers and the transport of the particle-bound pollutants downstream in river systems over long. In this study we focus on the potential release of the old contaminated sediments in the Rhine basin during extremely high discharges and low flows. The main aims of this study are to make an overview of the relevant knowledge gaps and to identify advisable research directions on the basis of existing information (data) and models. The main conclusion of this study is that insight is missing in the expected remobilisation and recontamination levels of contaminated sediments during extreme situations. The focus not only has to go on the historical contamination but also on the present-day contaminations, and on the identification of actual and potential problems. Better sediment and water quality measurements (e.g. one hour samples during flooding events) and models (source location) will allow us to get a better understanding of the sediment dynamics in the Rhine basin during extreme situations. This will give us a deeper insight in the substance interactions with sediment and in the water column (geometry of the pollutants)