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Effect of the Longitudinal Contact Location on Vehicle Dynamics Simulation

Burgelman, N. (author), Li, Z. (author), Dollevoet, R. (author)

This paper investigates the effect of the calculation of the longitudinal location of a wheel rail contact point on the wheelset’s motion in a vehicle dynamic simulation. All current vehicle dynamic software programs assume that the contact between wheel and rail takes place in the vertical plane through the wheelset’s rolling axis. However,...

journal article 2016

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Experimental Investigation Into the Condition of Insulated Rail Joints by Impact Excitation

Oregui, M. (author), Molodova, M. (author), Nunez, A. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)

This paper presents a feasibility study to determine if the health condition of Insulated Rail Joints (IRJs) can be assessed by examining their dynamic response to impact excitation. First, a reference dynamic behavior is defined in the frequency domain of 50-1200 Hz based on field hammer test measurements performed on a IRJ baseline (i.e., a...

journal article 2015

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Integrity monitoring-based ratio test for GNSS integer ambiguity validation

Li, L. (author), Li, Z. (author), Yuan, H. (author), Wang, L. (author), Yanqing, H. (author)

The combination of multiple global navigation satellite systems (GNSSs) is able to improve the accuracy and reliability, which is beneficial for navigation in safety–critical applications. Due to the relatively low accuracy of pseudorange observations, the single-epoch GNSS real-time kinematic (RTK) using phase observations can be utilized to...

journal article 2015

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Methodolody for porosimetry in virtual cementitious composites to economically and reliably estimate permeability

Li, K. (author), Stroeven, P. (author), Le, L.B.N. (author)

A novel methodology is described for porosimetry as well as for water transport through the pore system in dynamic DEM-based virtual cementitious materials. The pore network topology, the pore size distribution and the pore connectivity are assessed on the basis of a robotics-inspired pore delineation method and star volume measurements....

journal article 2015

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Analyzing the inundation pattern of the Poyang Lake floodplain by passive microwave data

Shang, H. (author), Li, J. (author), Menenti, M. (author)

The soil wetness condition is a useful indicator of inundation hazard in floodplains, such as the Poyang Lake floodplain. Special Sensor Microwave Imager (SSM/I) passive microwave data were used to monitor water-saturated soil and open water areas of the Poyang Lake floodplain from 2001 to 2008, capturing the inundation patterns of this area in...

journal article 2015

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Socio-hydrologic modeling to understand and mediate the competition for water between agriculture development and environmental health: Murrumbidgee River Basin, Australia

Van Emmerik, T.H.M. (author), Li, Z. (author), Sivapalan, M. (author), Pande, S. (author), Kandasamy, J. (author), Savenije, H.H.G. (author), Chanan, A. (author), Vigneswaran, S. (author)

Competition for water between humans and ecosystems is set to become a flash point in the coming decades in many parts of the world. An entirely new and comprehensive quantitative framework is needed to establish a holistic understanding of that competition, thereby enabling the development of effective mediation strategies. This paper presents...

journal article 2014

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Non-Vegetated Playa Morphodynamics Using Multi-Temporal Landsat Imagery in a Semi-Arid Endorheic Basin: Salar de Uyuni, Bolivia

Li, J. (author), Menenti, M. (author), Mousivand, A. (author), Luthi, S.M. (author)

Playas in endorheic basins are of environmental value and highly scientific because of their natural habitats of a wide variety of species and indicators for climatic changes and tectonic activities within continents. Remote sensing, due to its capability of acquiring repetitive data with synoptic coverage, provides a unique tool to monitor and...

journal article 2014

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An Energy based Method to Measure the Crowd Safety

Yin, H. (author), Li, D. (author), Zheng, X. (author)

How to evaluate crowd safety in crowded areas is a tough, but important, problem. According to accident-causing theory, uncontrolled release of hazardous energy among overcrowded pedestrians is the basic cause of crowd disaster. Therefore, crowd energy is modeled in this paper, which takes both pedestrian kinetic energy, pedestrian potential...

journal article 2014

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Relative role of bed roughness change and bed erosion on peak discharge increase in hyperconcentrated floods

Li, W. (author), Wang, Z.B. (author), Van Maren, D.S. (author), De Vriend, H.J. (author), Wu, B.S. (author)

River floods are usually featured by a downstream flattening discharge peak whereas a downstream increasing discharge peak is observed at a rate exceeding the tributary discharge during highly silt-laden floods (hyperconcentrated floods) in China’s Yellow River. It entails a great challenge in the downstream flood defence and the underlying...

journal article 2014

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Socio-hydrologic modeling to understand and mediate the competition for water between agriculture development and environmental health: Murrumbidgee River Basin, Australia (discussion paper)

Van Emmerik, T.H.M. (author), Li, Z. (author), Sivapalan, M. (author), Pande, S. (author), Kandasamy, J. (author), Savenije, H.H.G. (author), Chanan, A. (author), Vigneswaran, S. (author)

Competition for water between humans and ecosystems is set to become a flash point in the coming decades in many parts of the world. An entirely new and comprehensive quantitative framework is needed to establish a holistic understanding of that competition, thereby enabling the development of effective mediation strategies. This paper presents...

journal article 2014

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Influence of changes in surface layer properties on tire/pavement noise

Li, M. (author), Van Keulen, W. (author), Ceylan, H. (author), Van de Ven, M.F.C. (author), Molenaar, A.A.A. (author)

This paper investigates changes in tire/pavement noise caused by variations in the road surface characteristics. This research is based on the analysis of noise and surface characteristics collected from sections with 25 mm thickness thin layer surfacings in the Netherlands. Investigations are first performed on the measured noise levels in 1...

journal article 2013

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Morphological modeling using a fully coupled, total variation diminishing upwind-biased centered scheme

Li, W. (author), De Vriend, H.J. (author), Wang, Z. (author), Van Maren, D.S. (author)

High-resolution morphological modeling of fluvial processes with complex, rapidly varying flows has been limited so far by model accuracy or computational efficiency. One of the most widely used numerical algorithms is based on the total variation diminishing method, solved by either upwind or centered approaches. An upwind scheme preserves high...

journal article 2013

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Hydrological Changes of the Irtysh River and the Possible Causes

Huang, F. (author), Xia, Z. (author), Li, F. (author), Guo, L. (author), Yang, F. (author)

Hydrological changes of the Irtysh River were analyzed concerning the changes of annual runoff and its distribution features within a year measured by coefficient of variation and concentration degree. Abrupt changes were detected by the heuristic segmentation method. Possible causes of the hydrological changes were investigated considering...

journal article 2012

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The Evaluation of Traffic Control in Changsha City

Lu, S. (author), Li, J. (author), Van Zuylen, H. (author)

Different aspects of the traffic control system in the CBD of Changsha have been evaluated. A general issue is the safety conditions, which are evaluated qualitatively. The second issue is the low saturation flow observed on the intersections, that appear to be 20 to 30% lower than the ones in comparable situations in Europe or North America....

journal article 2012

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Travel time reliability during evacuation: The impact of heterogeneous driving behavior

Tu, H. (author), Pel, A.J. (author), Li, H. (author), Sun, L. (author)

Earlier studies have shown that driving behavior differs strongly in emergency conditions compared with behavior in normal traffic conditions. In this paper, these findings are followed up with an investigation of how these differences in driving behavior affect travel time reliability. In particular, the focus is on the effect of relatively...

journal article 2012

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Analysis on the Water Exchange between the Main Stream of the Yangtze River and the Poyang Lake

Zhao, J. (author), Li, J. (author), Yan, H. (author), Zheng, L. (author), Dai, Z. (author)

Analysis on the hydrologic characteristics of the main stream of the Yangtze River and Poyang Lake were studied to discuss the water exchange between the main stream of the Yangtze River and Poyang Lake before and after the operation of Three Gorges Reservoir, as well as in the typical dry year of 2006. The annual runoff distribution for dry...

journal article 2011

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Effect of spatial heterogeneity of runoff generation mechanisms on the scaling behavior of event runoff responses in a natural river basin

Li, H. (author), Sivapalan, M. (author)

This paper presents a theoretical investigation of the effects of spatial heterogeneity of runoff generation on the scaling behavior of runoff timing responses. A previous modeling study on the Illinois River Basin in Oklahoma had revealed a systematic spatial trend in the relative dominance of different runoff generation mechanisms,...

journal article 2011

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Investigating the lubricity and electrical insulation caused by sanding in dry wheel–rail contacts

Arias-Cuevas, O. (author), Li, Z. (author), Lewis, R. (author)

The adhesion (or available friction) in the wheel–rail contact is the most important parameter for the braking and traction operation of rail vehicles. Since the beginning of railway transportation, sanding from the locomotive has been a common practice to enhance the wheel–rail adhesion. In recent years, sanding from electrical multiple units ...

journal article 2009

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Development of engineered cementitious composites with limestone powder and blast furnace slag

Zhou, J. (author), Qian, S. (author), Sierra Beltran, M.G. (author), Ye, G. (author), Van Breugel, K. (author), Li, V.C. (author)

Nowadays limestone powder and blast furnace slag (BFS) are widely used in concrete as blended materials in cement. The replacement of Portland cement by limestone powder and BFS can lower the cost and enhance the greenness of concrete, since the production of these two materials needs less energy and causes less CO2 emission than Portland cement...

journal article 2009

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An innovative treatment concept for future drinking water production: Fluidized ion exchange – ultrafiltration – nanofiltration – granular activated carbon filtration

Li, S. (author), Heijman, S.G.J. (author), Verberk, J.Q.J.C. (author), Van Dijk, J.C. (author)

A new treatment concept for drinking water production from surface water has been investigated on a pilot scale. The treatment concept consists of fluidized ion exchange (FIEX), ultrafiltration (UF), nanofiltration (NF), and granular activated carbon filtration (GAC). The FIEX process removed calcium and other divalent cations; the UF membrane...

journal article 2009