Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Delft researcher develops design-rules for transport networks

25.09.2002


Large changes unnecessary for multimodal transport



Multimodal transport is not in need of redesigned networks, rather of well designed ones. This is one of the conclusions from the PhD research of Rob van Nes, who will defend his thesis on Wednesday 25 September at TU Delft. “A highway with too many on and off ramps actually becomes a main road. This might be handy, but it is not effective.” Van Nes, who carried out his research at TRAIL research school, laid the theoretical foundation for something which many people already suspected.

Multimodal transport is often seen as an interesting possibility to solve the current traffic problems such as traffic jams, unreachable areas and negative environmental effects. Combining the use of, for example, cars, trains and buses on certain routes, could emphasise the strengths and diminish the weaknesses of the network. Van Nes: “Multimodal transport is very useful, but the important question is actually: what exactly does an effective multimodal network look like? Is a different from the networks that we have at the moment, or are the connections between the networks more important?” According to Van Nes, two points are of great importance for an effective multimodal network: hierarchy and concentration in space.


Using mathematical models, Van Nes showed that multimodal networks are pointless unless one sticks to the hierarchy of the network. Van Nes: “In the hierarchy, a highway stands above a main road. The highway is for longer distances at higher speeds, a main road is for shorter distances and lower speeds.” If one does not maintain a clear separation, the result is an inefficient network. Van Nes: “A highway with many on and off ramps becomes a main road. It gets used for shorter distances, it becomes busier and the speed decreases.”

The concentration in space is also very important. Van Nes uses calculations to show that a public transport network can only work if there is a demand for transport. “If in a certain part of the city, there is no clear demand for transport, it is of little use to build higher level networks (fast tram/subway) alongside a the bus network in that area,” says Van Nes, “It is better to choose one of the two. This saves space, and especially money.” Van Nes has laid theoretical foundation for something that many people already suspected. Van Nes: “We can now provide proper arguments as to why we must build networks systematically, and on what points we should concentrate when trying to stimulate multimodal transport.”

Maarten van der Sanden | alfa
Further information:
http://www.tudelft.nl

More articles from Transportation and Logistics:

nachricht Study sets new distance record for medical drone transport
13.09.2017 | Johns Hopkins Medicine

nachricht Researchers 'count cars' -- literally -- to find a better way to control heavy traffic
10.08.2017 | Florida Atlantic University

All articles from Transportation and Logistics >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Fraunhofer ISE Pushes World Record for Multicrystalline Silicon Solar Cells to 22.3 Percent

25.09.2017 | Power and Electrical Engineering

Usher syndrome: Gene therapy restores hearing and balance

25.09.2017 | Health and Medicine

An international team of physicists a coherent amplification effect in laser excited dielectrics

25.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>