Improved road network design models with the consideration of various link patterns and road design elements

2007 ◽  
Vol 37 (11) ◽  
pp. 2281-2298 ◽  
Author(s):  
Jürg Stückelberger ◽  
Hans Rudolf Heinimann ◽  
Woodam Chung
Keyword(s):  
Road Network ◽  
Minimum Spanning Tree ◽  
Grid Cell ◽  
Cost Effective ◽  
Optimization Techniques ◽  
Construction Costs ◽  
Design Elements ◽  
Road Design ◽  
Tree Algorithms ◽  
Steep Terrain

The success of an automatic road network layout over steep terrain mainly depends on the model design. Most previous models have used a grid representation that considers only eight adjacent cells when evaluating feasible road links. Here, we present improved models and alignment constraints mapped on a mathematical graph for better designs that are more applicable under field conditions. We have refined the link pattern by considering up to 48 neighbouring cells and have introduced 16 directional classes per grid cell. Optimization techniques, such as shortest path, minimum spanning tree, and Steiner minimum tree algorithms, are used on the graph to derive a road network that is optimal in terms of its construction costs. These improved models have been applied to different mountainous project areas. Our results show that, by considering various link patterns and alignment constraints, one can determine more appropriate and cost-effective locations for road networks, especially in steep terrain.

Enhancing the application potential of dissipative controlled rocking connections through detailing and design

2021 ◽  
Author(s):  
Brandon McHaffie ◽  
Peter Routledge ◽  
Alessandro Palermo
Keyword(s):  
Linear Time ◽  
Time History ◽  
Cost Effective ◽  
Real Structure ◽  
Construction Costs ◽  
Alternative Design ◽  
Design Philosophy ◽  
History Analysis ◽  
Application Potential ◽  
The University

<p>Research on low-damage systems has been significant in the past decade. These systems combine post- tensioning, which provides self-centring; and typically use replaceable devices, which give energy dissipation. WSP has used recent research, carried out at the University of Canterbury, on low-damage bridge piers and applied this into a real structure – the Wigram-Magdala Link Bridge. This is believed to be the first bridge in New Zealand and possibly worldwide to adopt such a system. Given this was the first application of the system to a real structure, there were some valuable learnings during design and construction. Firstly, the application of axial dissipaters has some limitations due to available material sizes, construction difficulty and aesthetics. Secondly, there is still some additional cost and complexity associated with using the low-damage system. Given these difficulties, this paper presents an alternative design philosophy which better captures the benefits of the low-damage system, which include cost-effective repair method, controlled damage and additional robustness and resilience. The alternative design philosophy presented is expected to result in reduced construction costs by reducing pier and foundation demands. Peak displacements and forces will be compared to the results from non-linear time history analysis to verify the performance of the low-damage connection using scaled ground motions. Furthermore, the paper will present the possible application of an alternative dissipation device, the lead extrusion damper, which can further improve the performance of low-damage connections.</p>

Topology Optimization in the Conceptual Design: Take the Frame of a Bender as Example

2011 ◽  
Vol 267 ◽  
pp. 297-301
Author(s):  
Yong Wang ◽  
Guo Niu Zhu ◽  
Bo Yu Sun
Keyword(s):  
Topology Optimization ◽  
Design Process ◽  
Mechanical Design ◽  
Cost Effective ◽  
Optimization Techniques ◽  
Structural Topology Optimization ◽  
Structural Topology ◽  
Effective Manner ◽  
Stress And Deformation ◽  
Design Proposal

The paper is concerned with topology optimization in the mechanical design process. The disadvantage of current process of mechanical design is discussed and a new design process based on structural topology optimization is presented. The design process with structural topology optimization in mechanical design is discussed by the example of the frame of a bender. Static analysis is made to the original model first according to the whole structure and working characteristic of the machine, the stress and deformation distribution are obtained and then topology optimization is carried out. On the basis of topology optimization, the layout of the initial design proposal is obtained and the weight of the frame is substantially reduced while the performance enhanced. The application of the method demonstrates that through innovative utilization of the topology optimization techniques, the conceptual proposals can be obtained and the overall mechanical design process can be improved substantially in a cost effective manner.

scholarly journals Decision to paving solutions in road infrastructures based on life-cycle assessment

2016 ◽  
Vol 11 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Maria de Lurdes Antunes ◽  
Vânia Marecos ◽  
José Neves ◽  
João Morgado
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Decision Process ◽  
Life Cycle Cost ◽  
Road Network ◽  
Construction Costs ◽  
Road Pavement ◽  
Pavement Structures ◽  
Using Data ◽  
Term Performance

The construction and maintenance of a road network involve the expenditure of large budgets. In order to optimize the investments in road infrastructures, designers and decision makers should have the instruments to make the most suitable decision of paving solutions for each particular situation. The life-cycle assessment is an important tool of different road pavement solutions with this purpose. This paper presents a study concerning the life-cycle cost analysis of different flexible and semi-rigid paving alternatives, with the objective to contribute for a better support in the decision process when designing new pavement structures. The analysis was carried out using data on construction costs of certain typical pavement structures and taking into consideration appropriate performance models for each type of structure being selected. The models were calibrated using results from long term performance studies across Europe and the maintenance strategies considered have taken into account the current practice also found in the European context. Besides the life-cycle administration costs, the proposed methodology also deals with user and environmental costs through its inclusion in the decision process using multi-criteria analysis. It was demonstrated that this methodology could be a simple and useful tool in order to achieve the most adequate paving solutions of a road network, in terms of construction and maintenance activities, based simultaneously on technical, economic and environmental criteria.

scholarly journals A Framework for the Selection of Optimum Offshore Wind Farm Locations for Deployment

Energies ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1855 ◽  
Author(s):  
Varvara Mytilinou ◽  
Estivaliz Lozano-Minguez ◽  
Athanasios Kolios
Keyword(s):  
Decision Making ◽  
Wind Energy ◽  
Wind Farm ◽  
Cost Effective ◽  
Optimization Techniques ◽  
Offshore Wind ◽  
Moray Firth ◽  
The Uk ◽  
The Given ◽  
Nondominated Sorting

This research develops a framework to assist wind energy developers to select the optimum deployment site of a wind farm by considering the Round 3 available zones in the UK. The framework includes optimization techniques, decision-making methods and experts’ input in order to support investment decisions. Further, techno-economic evaluation, life cycle costing (LCC) and physical aspects for each location are considered along with experts’ opinions to provide deeper insight into the decision-making process. A process on the criteria selection is also presented and seven conflicting criteria are being considered for implementation in the technique for the order of preference by similarity to the ideal solution (TOPSIS) method in order to suggest the optimum location that was produced by the nondominated sorting genetic algorithm (NSGAII). For the given inputs, Seagreen Alpha, near the Isle of May, was found to be the most probable solution, followed by Moray Firth Eastern Development Area 1, near Wick, which demonstrates by example the effectiveness of the newly introduced framework that is also transferable and generic. The outcomes are expected to help stakeholders and decision makers to make better informed and cost-effective decisions under uncertainty when investing in offshore wind energy in the UK.

scholarly journals A Cost-Effective Person-Following System for Assistive Unmanned Vehicles with Deep Learning at the Edge

Machines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 49
Author(s):  
Anna Boschi ◽  
Francesco Salvetti ◽  
Vittorio Mazzia ◽  
Marcello Chiaberge
Keyword(s):  
Deep Learning ◽  
Cost Effective ◽  
Vital Statistics ◽  
Unmanned Vehicles ◽  
Optimization Techniques ◽  
World Population ◽  
Service Robotics ◽  
Power Efficient ◽  
Person Following ◽  
The World

The vital statistics of the last century highlight a sharp increment of the average age of the world population with a consequent growth of the number of older people. Service robotics applications have the potentiality to provide systems and tools to support the autonomous and self-sufficient older adults in their houses in everyday life, thereby avoiding the task of monitoring them with third parties. In this context, we propose a cost-effective modular solution to detect and follow a person in an indoor, domestic environment. We exploited the latest advancements in deep learning optimization techniques, and we compared different neural network accelerators to provide a robust and flexible person-following system at the edge. Our proposed cost-effective and power-efficient solution is fully-integrable with pre-existing navigation stacks and creates the foundations for the development of fully-autonomous and self-contained service robotics applications.

scholarly journals Using modelled discharge to develop satellite-based river gauging: a case study for the Amazon Basin

2018 ◽  
Vol 22 (12) ◽  
pp. 6435-6448 ◽  
Author(s):  
Jiawei Hou ◽  
Albert I. J. M. van Dijk ◽  
Luigi J. Renzullo ◽  
Robert A. Vertessy
Keyword(s):  
River Discharge ◽  
Water Resource Management ◽  
Large Scale ◽  
Amazon Basin ◽  
Water Cycle ◽  
Detection System ◽  
Grid Cell ◽  
Cost Effective ◽  
Satellite Observation ◽  
Moderate Resolution Imaging Spectroradiometer

Abstract. River discharge measurements have proven invaluable to monitor the global water cycle, assess flood risk, and guide water resource management. However, there is a delay, and ongoing decline, in the availability of gauging data and stations are highly unevenly distributed globally. While not a substitute for river discharge measurement, remote sensing is a cost-effective technology to acquire information on river dynamics in situations where ground-based measurements are unavailable. The general approach has been to relate satellite observation to discharge measured in situ, which prevents its use for ungauged rivers. Alternatively, hydrological models are now available that can be used to estimate river discharge globally. While subject to greater errors and biases than measurements, model estimates of river discharge do expand the options for applying satellite-based discharge monitoring in ungauged rivers. Our aim was to test whether satellite gauging reaches (SGRs), similar to virtual stations in satellite altimetry, can be constructed based on Moderate Resolution Imaging Spectroradiometer (MODIS) optical or Global Flood Detection System (GFDS) passive microwave-derived surface water extent fraction and simulated discharge from the World-Wide Water (W3) model version 2. We designed and tested two methods to develop SGRs across the Amazon Basin and found that the optimal grid cell selection method performed best for relating MODIS and GFDS water extent to simulated discharge. The number of potential river reaches to develop SGRs increases from upstream to downstream reaches as rivers widen. MODIS SGRs are feasible for more river reaches than GFDS SGRs due to its higher spatial resolution. However, where they could be constructed, GFDS SGRs predicted discharge more accurately as observations were less affected by cloud and vegetation. We conclude that SGRs are suitable for automated large-scale application and offer a possibility to predict river discharge variations from satellite observations alone, for both gauged and ungauged rivers.

Use of Foamed Tar for Construction of Flexible Pavement with Existing Unpaved Road Structure

2003 ◽  
Vol 1819 (1) ◽  
pp. 314-322
Author(s):  
Bruce S. Morton ◽  
Alex T. Visser ◽  
Emile Horak
Keyword(s):  
Road Network ◽  
Flexible Pavements ◽  
Performance Testing ◽  
Cost Effective ◽  
Engineering Properties ◽  
Unpaved Roads ◽  
Reconstruction Methods ◽  
Effective Manner ◽  
Low Volume

Low-volume and unpaved roads constitute the majority of the road network throughout the developing and developed world. Upgrading these unpaved roads to conform to standards of low-volume flexible asphalt pavements is a costly exercise. In most instances, this involves constructing an entirely new pavement base. Recent technological advances in the field of deep in situ recycling have provided pavement engineers with an alternative to standard rehabilitation and reconstruction methods of flexible pavements. One such technique of stabilization is foamed tar treatment of inferior natural pavement materials through the application of deep in situ recycling to produce a stabilized base for lowvolume flexible pavements. Foamed tar technology and the concept of deep in situ recycling, and its advantages over current reconstruction methods, were reviewed. Health aspects relating to implementation of the stabilization process were addressed with respect to the use of gasifier tar in a controlled recycling environment. The engineering properties of foamed tar mixes were compared with existing stabilization techniques. A test section was constructed with particular attention to the flexibility of foamed tar for placement time, workability, and durability to environmental conditions. Performance testing results were analyzed. In conclusion, the benefits of foamed tar stabilization for developing an improved road network in a cost-effective manner were evaluated.

scholarly journals Restoring mass conservation to shallow ice flow models over complex terrain

2013 ◽  
Vol 7 (1) ◽  
pp. 229-240 ◽  
Author(s):  
A. H. Jarosch ◽  
C. G. Schoof ◽  
F. S. Anslow
Keyword(s):  
Complex Terrain ◽  
Model Performance ◽  
Grid Cell ◽  
Mass Conservation ◽  
Ice Flow ◽  
Flow Models ◽  
Mountainous Regions ◽  
Steep Terrain ◽  
Flux Limiting ◽  
Ice Model

Abstract. Numerical simulation of glacier dynamics in mountainous regions using zero-order, shallow ice models is desirable for computational efficiency so as to allow broad coverage. However, these models present several difficulties when applied to complex terrain. One such problem arises where steep terrain can spuriously lead to large ice fluxes that remove more mass from a grid cell than it originally contains, leading to mass conservation being violated. This paper describes a vertically integrated, shallow ice model using a second-order flux-limiting spatial discretization scheme that enforces mass conservation. An exact solution to ice flow over a bedrock step is derived for a given mass balance forcing as a benchmark to evaluate the model performance in such a difficult setting. This benchmark should serve as a useful test for modellers interested in simulating glaciers over complex terrain.

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