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Full-Text Articles in Engineering
Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell
Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell
SMART Infrastructure Facility - Papers
Development of transport infrastructure has significant challenges including acquisition lag, phased evolution, multiple disparate stakeholders and environment-specific issues. The Asset Standards Authority (ASA) at TfNSW is introducing MBSE to address these challenges. Instrumental to the introduction is the development of a framework that structures the available data and provides guidance and traceability between the data sets. This framework combines the enterprise-level drivers with the lower level drivers such as standards to outline a generic conceptual design for a transport system. This conceptual design is then used to guide future system development. The outcome is future project information based on greater, …
On Asymptotic Behaviour And W 2, P Regularity Of Potentials In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang
On Asymptotic Behaviour And W 2, P Regularity Of Potentials In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang
Faculty of Engineering and Information Sciences - Papers: Part A
© 2014, Springer-Verlag Berlin Heidelberg. In this paper we study local properties of cost and potential functions in optimal transportation. We prove that in a proper normalization process, the cost function is uniformly smooth and converges locally smoothly to a quadratic cost x · y, while the potential function converges to a quadratic function. As applications we obtain the interior W2, p estimates and sharp C1, α estimates for the potentials, which satisfy a Monge–Ampère type equation. The W2, p estimate was previously proved by Caffarelli for the quadratic transport cost and the associated standard Monge–Ampère equation.
Global Optimization Method For Robust Pricing Of Transportation Networks Under Uncertain Demand, Shuaian Wang, Lauren Gardner, S.Travis Waller
Global Optimization Method For Robust Pricing Of Transportation Networks Under Uncertain Demand, Shuaian Wang, Lauren Gardner, S.Travis Waller
Faculty of Engineering and Information Sciences - Papers: Part A
We extend the existing toll pricing studies with fixed demand to stochastic demand. A new and practical second-best pricing problem with uncertain demand is proposed and formulated as a stochastic mathematical program with equilibrium constraints. In view of the problem structure, we develop a tailored global optimization algorithm. This algorithm incorporates a sample average approximation scheme, a relaxation-strengthening method, and a linearization approach. The proposed global optimization algorithm is applied to three networks: a two-link network, a seven-eleven network and the Sioux-Falls network. The results demonstrate that using a single fixed estimation of future demand may overestimate the future system …
Optimal Transportation On The Hemisphere, Sun-Yung Alice Chang, Jiakun Liu, Paul Yang
Optimal Transportation On The Hemisphere, Sun-Yung Alice Chang, Jiakun Liu, Paul Yang
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, we study the optimal transportation on the hemisphere, with the cost function c(x, y) = 1/2d2 (x, y), where d is the Riemannian distance of the round sphere. The potential function satisfies a Monge-Ampere type equation with natural boundary condtion. In this critical case, the hemisphere does not satisfy the c-convexity assumption. We obtain the priori oblique derivate estimate, and in the special case of two demensional hemisphere, we obtain the boundary C2 estimate. Our proof does not require the smoothness of densities.
Efficiency And Equity Of Speed Limits In Transportation Networks, Shuaian Wang
Efficiency And Equity Of Speed Limits In Transportation Networks, Shuaian Wang
Faculty of Engineering and Information Sciences - Papers: Part A
This paper examines the impact of speed limits on network efficiency, in terms of total travel time of all road users, and equity among road users from different origin-destination (OD) pairs, in terms of the change of travel time after imposing a speed limit scheme. We find that after imposing a speed limit scheme, the total travel time of all road users may decrease or increase; road users of some OD pairs may experience longer travel time, while other OD pairs may have shorter travel time. In view of the importance of speed limits on network efficiency and equity, we …
Physical And Chemical Ground Improvement For Sustainable Transportation Infrastructure Under Cyclic Loads, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Jayan S. Vinod, Sanjay Nimbalkar
Physical And Chemical Ground Improvement For Sustainable Transportation Infrastructure Under Cyclic Loads, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Jayan S. Vinod, Sanjay Nimbalkar
Faculty of Engineering - Papers (Archive)
Railways form one of the major worldwide transportation networks and they continue to provide quick and safe public and freight transportation. In order to compete with other modes of transportation and to meet the ever growing demand of public and freight transport, railway industries face challenges to improve their efficiency and decrease the costs of maintenance and infrastructure. Large cyclic loading from heavy haul and passenger trains often leads to progressive deterioration of the track. The excessive deformations and degradations of the ballast layer and unacceptable differential settlement or pumping of underlying soft and compressible subgrade soils necessitate frequent costly …
Regularity Of Monge-Ampere Equations In Optimal Transportation, Jiakun Liu
Regularity Of Monge-Ampere Equations In Optimal Transportation, Jiakun Liu
Faculty of Engineering and Information Sciences - Papers: Part A
We consider some recent regularity results for the Monge-Ampère equation arising in the optimal transportation problem. The Monge-Ampère equation under consideration has the following type
Regularity In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang
Regularity In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang
Faculty of Engineering and Information Sciences - Papers: Part A
In this talk, we give some estimates for solutions to the Monge-Amp`ere equation arising in optimal transportation. The Monge-Amp`ere equation under consideration has the following type
Earthquake Engineering For Transportation Network In Low To Moderate Seismicity Regions, M Neaz Sheikh, Frederic Legeron, Hing Ho Tsang, Nelson Lam, Timothy J. Mccarthy
Earthquake Engineering For Transportation Network In Low To Moderate Seismicity Regions, M Neaz Sheikh, Frederic Legeron, Hing Ho Tsang, Nelson Lam, Timothy J. Mccarthy
Faculty of Engineering - Papers (Archive)
Major seismic events during the past few decades have continued to demonstrate the destructive power of earthquakes, with failures to buildings, bridges, industrial and port facilities, as well as giving rise to great economic losses. However, in low to moderate seismicity regions, seismic resistant design is still considered complicated and expensive in terms of actual seismic risk. This is partly due to the fact that design codes do not have any special consideration for these regions; also, economic factors have not been integrated fully with the design principles. Bridges are the most critical components of the transportation network, as failure …
Transportation Boundaries Of Slug-Flow In A Horizontal Pipeline, David B. Hastie, P R Guiney, Peter W. Wypych, Renhu Pan
Transportation Boundaries Of Slug-Flow In A Horizontal Pipeline, David B. Hastie, P R Guiney, Peter W. Wypych, Renhu Pan
Faculty of Engineering - Papers (Archive)
An experimental program was established to investigate boundaries in low-velocity slug-flow pneumatic conveying. A straight horizontal pipeline of L=21m and D=60.3mm ID was set up for actual conveying trials and a simple rig was designed and built specifically to simulate the boundaries of slug-flow. After running several tests in the simulation rig with a sample of the product, the slug-flow were able to be determined with good accuracy. Combined with the theoretical correlations developed to determine pressure drop in slug-flow, reliable operating conditions can be predicted. Good agreement was achieved after the predicted results were compared with the experimental results …