Results 111 to 120 of about 414,188 (295)

Analysis of the abnormal wear of the pantograph contact strip through combined experimental and simulation approaches

Scientific Reports
The carbon contact strip of pantograph collects current from the overhead catenary to power the train, inevitably causing wear to the contact surface. This paper addresses the abnormal wear of the pantograph carbon contact strip, a challenged accident ...
Xingshuai Zhi, Ning Zhou, Haifei Wei, Hongming Chen, Yao Cheng, Yi Sun, Langtao Zhao, Guanhua Huang, Weihua Zhang   +8 more
doaj   +1 more source

What Happens When a Black Swan Meets a Gray Rhino? Reflections on the Evaluation Market in Transformative Times

New Directions for Evaluation, EarlyView.
ABSTRACT This chapter examines recent disruptions in the U.S. evaluation market through the combined lens of the Evaluation Marketplace Framework and the Black Swan/Gray Rhino typology. We argue that the Trump Administration's abrupt reduction in federal evaluation commissioning constitutes a Black Swan shock, whereas the long‐anticipated technological
Steffen Bohni Nielsen, Sebastian Lemire
wiley   +1 more source

Ppp In Light Rail Transit Systems In Spain

, 2012
{"references": ["Litman, T. (2007). Evaluating rail transit benefits: A comment,\nTransport Policy, 14, 94-97.", "Bruijn, H. and Veeneman, W. (2009). Decision-making for light rail,\nTransport Research Part A, 43, 349-359.", "Babalik-Sutcliffe, E. (2002). Urban rail systems: analysis of the factors\nbehind success, Transport Reviews, 22(4), 415-447.", "
Carpintero Lopez, Samuel, Barcham, R.
openaire   +2 more sources

Active Stiffness Modulation of Flexible PDMS Elastomer by Embedding Shape Memory Alloy Wires: Fabrication and Modeling

FlexTech, EarlyView.
Active stiffness modulation is achieved in NiTi shape memory alloy‐reinforced PDMS and carbon fiber‐epoxy composites, with reversible 3‐fold modulus increase via Joule heating and validated predictive models, which resolves longstanding adaptive design challenges.
Xi Yi, Dongjie Jiang
wiley   +1 more source

New Measurement Methods for Transition Resistance of Rail Tracks in Urban Rail Transit

Chengshi guidao jiaotong yanjiu
[Objective] To analyze the impact of stray currents on buried pipelines and electrical equipment during metro operation, it is necessary to study new measurement methods for the transition resistance of rail tracks in urban rail transit. [Method] The principle of measuring rail track transition resistance is introduced.
LI Shichen, YU Xianhu, LI Jinglong
openaire   +1 more source

Revisiting the Nexus Between Trade Liberalisation and Income Inequality: The Case of Sub‐Saharan African Countries

International Journal of Finance &Economics, EarlyView.
ABSTRACT This paper examines the impact of trade liberalisation on income inequality across 24 Sub‐Saharan African (SSA) countries from 2000 to 2020. Using IV‐Tobit and 2SLS models, we consistently find that greater trade openness significantly exacerbates inequality in the region. Critically, we document an inverted U‐shaped relationship between trade
Guivis Zeufack Nkemgha, Le Roi Nso Fils, Ulrich Kevin Kamwa   +2 more
wiley   +1 more source

Train Trajectory-Following Control Method Using Virtual Sensors

Sensors
Trajectory-following control is the basis for the practical application of an articulated virtual rail train transportation system. In this paper, a planar nonlinear dynamics model of an articulated vehicle is derived using the Euler–Lagrange method.
Youpei Huang, Xiaoguang Ma, Lihui Ren
doaj   +1 more source

Uncovering the key bilateral trade linkages in the U.S. domestic food supply chain through disruption simulations

Journal of the Agricultural and Applied Economics Association, EarlyView.
Abstract This paper uses counterfactual simulations to examine the impact of bilateral trade linkage disruptions on the U.S. agricultural and food trade system. Using an econometric gravity model, we estimate the relationship between disruptions and trade flows, identify critical state‐to‐state trade linkages whose disruption would significantly impact
Taejun Mo, Sandy Dall'erba
wiley   +1 more source

Rail transits effect on population growth. : A comparison between different rail transit types

, 2023
The study examines the relationship between accessibility to public rail transit stations and population growth. Accessibility is measured in time, as in how long it takes to walk to a rail station. The study uses service areas created in a GIS based on how far a person can walk in 10 minutes, comparing the average population growth within these ...
openaire   +1 more source

Exploring production of social and economic value in social enterprises through a business model framework

Strategic Change, EarlyView.
Abstract This study explores how social enterprises create social and economic value through business models that support ex‐offenders. The work was motivated by a request for help from an entrepreneur wishing to establish a business that supports ex‐offender rehabilitation.
Elizabeth Green, Peter Bradley, Glenn Parry   +2 more
wiley   +1 more source