4,385 research outputs found
The metro and the city: interaction with the urban landscape in the new underground stations in Valencia 1995-2010
No full textThe first stations of the Valencia subway lines were accessible by conventional
metro entrances, stairs leading to an underground corridor or hallway, invisible
from the street and from where you came, directly or through other corridors, to
the platforms. In the new metro lines from the network of FGV Ferrocarriles de
la Generalitat Valenciana (Railways of the Regional Government of Valencia)
built between 1995 and 2010 the architectural design of the stations is addressed
in a different way from design strategies that seek greater interaction with the
public space and the urban environment. To expose these strategies of interaction
with the urban environment, the paper uses as case studies several stations
designed by the author, belonging to lines 3 and 5 of the Valencia Metro
network.Pérez Igualada, J. (2015). The metro and the city: interaction with the urban landscape in the new underground stations in Valencia 1995-2010. WIT Transactions on the Built Environment. 146:363-374. doi:10.2495/UT150291S36337414
Co-Authorship Network for Scientific and Technical Papers, Published by at least one WIT Author
No full textWhat This Is
The diagram is a visual representation of collaborations between authors of WIT papers, who are represented by the circles in this image. Any co-authorship relation between two authors is represented by a connecting line.
• The colour of a line reflects the number of times that those two authors have worked together.
• The colour of a circle reflects the average impact of papers published by that author (average times cited)
• The size of a circle is proportional to the number of papers attributed to that author in the data used to generate the diagram.
The Data Used
The data used, comes from the Web of Knowledge. The Web of Knowledge is an index of all of the citations in 23,000 of the top academic and scientific journals. It should be noted that the data is not comprehensive, as there are many other journals in existence. Also, the index is biased in favour of the hard sciences. Disciplines related to humanities, arts and social sciences are very under-represented in this dataset.
The Software Used
The software used to generate this diagram is called Gephi. This is an open source graph visualisation tool. The software is developed by a French-based non-profit consortium. It started as a Google ‘Summer of Code’ initiative.
The Benefits
Analysis of networks using graph theory is a discipline that has come into its own of late, as improvements in technology have made possible the development of new tools, namely graph databases and visualisation software such as Gephi.
In the context of research, this kind of analysis can be a powerful tool for strategic planning, capacity building, identifying collaborative opportunities, and for finding efficiencies in large organisations
Cleaner fuels to reduce emissions of CO2, NOx and PM10 by container ships: A solution or a box of Pandora?
No full textTransport vehicles contribute to the on going rise in emissions of CO2 worldwide and emit large amounts of NOx and PM10. The growing demand for container transport is only sustainable if transport becomes ‘greener’. There are innovations, which unite economic and environmental interests. One example it the ongoing increase in ship size, which reduces the cost of shipping by reducing fuel consumption and emissions per container. Another example is the use of alternative fuel (blend)s in ship engines. The central theme in this paper is to better understand the impact of replacing standard fuels in engines of large(r) container ships by alternative fuels (biodiesel, LNG/CNG) on CO2 NOx and PM10 emissions. This leads to the following questions: Can alternative fuels help to significantly reduce CO2, NOx and PM10 emissions in port areas? Does their use allow compensation of the growth in emissions due to the growth in container shipping? It is shown for a typical seaport container terminal that cleaner fuels can contribute to lowering these emissions, even if the volume of containers handled by this terminal triples. The use of what seem at first glance cleaner fuels may however open a box of Pandora as a widespread use of organic biofuel may create serious other environmental problems, additional pressure on local food supply and social stability in already vulnerable areas of the world. More use of natural gas also raises serious environmental concerns.Transport & PlanningCivil Engineering and Geoscience
Evaluation of robustness indicators using railway operation simulation
No full textThe classical way of evaluating the robustness of railway timetables is the use of microscopic simulation. This is precise and offers a high level of detail, but it also requires a high amount of work. The alternative is to use robustness indicators that directly or indirectly indicate the robustness of a railway system. However, the semantics of these are mainly unknown and indicators are therefore best for comparison of alternatives. The paper therefore reviews and evaluates different robustness indicators against a microscopic simulation. This evaluation show that the indicators compare well to the microscopic simulation and are, to some extent, able to predict the outcome of the simulation. © 2014 WIT Press
The assessment of depression in children aged 6 through 8
No full textContains fulltext :
mmubn000001_38530532x.pdf (Publisher’s version ) (Closed access)RU Radboud Universiteit Nijmegen, 15 oktober 2002Promotor : Bruyn, E.E.J. De Co-promotores : Wit, C.A.M. de, Scholte, R.H.J.96 p
Estimated impact of CO2 and NOx emission reduction targets on car ownership and car use in The Netherlands
No full textDensely populated areas are major sources of air, soil and water pollution. Agriculture, manufacturing, consumer households and road traffic all have their share. This is particularly true for the country featured in this paper: the Netherlands. Continuous pollution of the air and soil manifests itself as acification, decalcification and eutrofication. Biodiversity becomes lower and lower in nature areas. Biological farms are also under threat. In case of mobility, local air pollution may have a huge health impact. Effective policy is called for, after high courts blocked construction projects, because of foreseen building- and transport-related NOx emissions. EU law makers are after Dutch governments, because these favoured economics and politics over environmental and liveability concerns. But, people in the Netherlands are strongly divided. The latest provincial elections were dominated by environmental concerns, next to many socio-economic issues. NOx and CO2 emissions by passenger cars are in focus. Technical means and increasing fuel economy norms strongly reduced NOx emissions to a still too high level. A larger number of cars neutralized a technological reduction of CO2 emissions. The question is: What would be the impact of a drastic mandatory reduction in CO2, NOx, and PM10 emissions on car ownership and use in the Netherlands? The authors used literature, scenario analysis and simulation modelling to answer this question. Electric mobility could remove these emissions. Its full impact will only be achieved if the grid-mix, which is still dominated by fossil fuels, becomes green(er), which is a gradual, long-term, process. EVs compete with other consumers of electricity, as many other activities, such as heating, are also electrifying. With the current grid-mix, it is inevitable that the number of km per vehicle per year is reduced to reach the scenario targets (−25% resp. −50% CO2 emissions by cars). This calls for an individual mobility budget per car user.Transport and Plannin
Network effects in railways
No full textRailway operation is often affected by network effects as a change in one part of the network can influence other parts of the network. Network effects occur because the train runs may be quite long and since the railway system has a high degree of interdependencies as trains cannot cross/overtake each other everywhere in the network. First this paper describes network effects in general (section 1). In section 2 the network effects for trains and how they can be measured by scheduled waiting time is described. When the trains are affected by network effects the passengers are also affected. Therefore, sections 3 and 4 describe the network effects for passengers and how they can be measured using passenger delay models. Before the concluding remarks in section 6, section 5 discusses how the operation can be improved by examining network effects in the planning process. © 2012 WIT Press
Monozygous triplets discordant for transient neonatal diabetes mellitus and for imprinting of the TNDM differentially methylated region
No full textTransient neonatal diabetes mellitus (TNDM) is associated with paternal over-expression of an imprinted locus on chromosome 6q24, which contains one differentially methylated region (DMR); maternal demethylation at the DMR accounts for approximately 20% of cases. Here we report female monozygous triplets, two of whom have TNDM arising from loss of maternal methylation within the TNDM DM
Zr-based conversion coatings for multi-metal substrates
No full textIn this PhD work, a new surface treatment based on the application of Zr-based conversion coatings by immersion in a Cu containing Zr-based conversion solution was investigated as a replacement of the traditional phosphating process for the automotive industry. Nowadays most of the cars are made of a combination of different metals, therefore, one of the aims of this work is to study the formation mechanism of Zr-based conversion coatings on different metallic surfaces. Prior to the immersion in the conversion solution, the metals are exposed to a surface conditioning treatment to remove the contaminants which might interfere in the formation of the film. Taking this into consideration, this PhD thesis is also focused on understanding the effect of the surface conditioning treatments on the deposition mechanism and kinetics of Zr-based conversion coatings on different alloys. In the first part of this PhD work, the formation mechanism and surface characteristics of Zr-based conversion coatings deposited on aluminium alloy 6014 (AA6014), cold rolled steel and hot dip galvanized steel were evaluated. This was done by combining Open Circuit Potential (OCP) measurements during the formation of the coatings and ex-situ surface analytical techniques. The results indicated that regardless of the metal, the deposition of the Zr-based conversion coating initiates and proceeds by the same mechanism. This process is initiated by the chemical dissolution of the oxide film by the free fluorides present in the conversion bath. This is followed by the deposition of the Zr-based conversion films, which is triggered by the alkalization of the metal/solution interface. Furthermore, the results also showed that the surface chemistry, elemental distribution and thickness of the resulting Zr based conversion coatings highly depend on the type of metallic substrate. The effect of convection on the formation of Zr-based conversion coatings on different metals was also assessed by implementing in-situ OCP measurements and Auger Electron Spectroscopy (AES) depth profiles. The results indicate that the conversion film thickness increases with the conversion bath stirring rate, but this increment depends on the metal substrate. The second part of this PhD thesis is focused on understanding the effect of the surface conditioning treatments on the deposition of Zr-based conversion coatings. A surface conditioning treatment can significantly modify the chemistry of the oxide film, such as the fraction of hydroxyl groups present in the outer part of the films. To investigate the influence of this parameter on the formation of the Zr-based conversion films, different model surface conditioning treatments were implemented in order to form oxide films with different hydroxyl fractions at similar oxide layer thicknesses prior to immersion in the conversion solution. The elemental distribution and surface chemistry of differently treated AA6014 and cold rolled steel specimens before and after the formation of the films were evaluated by means of AES depth profiles, Field Emission AES and X-ray Photoelectron Spectroscopy (XPS). The OCP as a function of time was recorded during the formation of the films in order to study the electrochemical reactions involved in the process insitu. The results show that for AA6014, higher hydroxyl fractions are beneficial for the formation of the Zr-based conversion coatings. The observed trend is linked to the effect of surface hydroxyls in the first stage of the formation of the Zr-based conversion coating, which is dissolution of the metal (hydr)oxides by the free fluorides present in the conversion solution. In addition, the results presented in this study indicate an inhomogeneous Cu distribution within the Zr-based conversion layers deposited on the differently treated AA6014. It was concluded that these variations in the Cu composition at the surface originate from the surface conditioning treatment and the Zr-based conversion treatment. The results presented in this part of this PhD thesis show that the largest impact of the surface hydroxyls on the formation of Zr-based conversion coatings is observed on AA6014, followed by zinc and for cold rolled steel no effect was observed.Materials Science & EngineeringMechanical, Maritime and Materials Engineerin
More space and improved living conditions in cities with autonomous vehicles
No full textMany people live in cities today. Many more will do so in future. This increases the demand for space and (space for) transport. Space to expand roads is usually scarce. Building tunnels or elevated bridges is very expensive. Solving one bottleneck creates a next bottleneck downstream. More road infrastructure leads to more cars and more cars to more congestion and externalities. Megacitiesinvest in large-scale (preferably underground) public transport. Smaller cities lack the required number of travellers and the money to warrant the high investment costs. In a sustainable city the supply of goods, services, water, energy and transportation should differ from the current practice.New car technologies are interesting, in particular the nearly roadworthy self-driving (autonomous) cars. It is still very demanding to let these share roads with conventional cars, cyclists and pedestrians. Cities lack the space for a separate network for these cars, yet. A socially challenging alternative would be to replace all private cars by shared electric self-driving cars and small shuttlebuses and integrate these with mass transport, cycling and walking. Passenger transport would need much less space for driving and parking. Congestion will vanish. Local air pollution, noise and use of resources to produce cars and road materials are reduced. Reclaimed space can be used to create a more sustainable and social environment and to optimize city logistics. The building blocks of such a (public-private) system exist already or will become available in the future
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