Basis enrichment and solid–fluid coupling for model‐reduced fluid simulation

We present several enhancements to model‐reduced fluid simulation that allow improved simulation bases and two‐way solid–fluid coupling. Specifically, we present a basis enrichment scheme that allows us to combine data‐driven or artistically derived bases with more general analytic bases derived from Laplacian eigenfunctions. We handle two‐way solid–fluid coupling in a time‐splitting fashion—we alternately timestep the fluid and rigid body simulators, while taking into account the effects of the fluid on the rigid bodies and vice versa. We employ the vortex panel method to handle solid–fluid coupling and use dynamic pressure to compute the effect of the fluid on rigid bodies. Copyright © 2014 John Wiley & Sons, Ltd.     

Traveling wave fault locator for mixed,overhead, and underground teed transmission feeders

Society is increasingly concerned about the environmental impact of energy systems, and prefers to locate power lines underground. This is especially true in regions of outstanding natural beauty or if they affect environmental/political/planning constrained areas. However, the use of underground sections within a predominantly overhead feeder introduces significant problems for the auto‐reclosure of circuit breakers. Auto‐reclosure is important on an overhead feeder, since most faults are transient and, once the feeder has been de‐energized, the insulation strength of the air at the fault recovers and the line can be restored to service. Faults on an underground cable are different because, once the insulation is damaged, the fault is normally permanent. In addition, if the breaker is allowed to reclose onto a cable fault, the area of damage increases and health and safety concerns exist for humans in the vicinity of the faulted cable section. The main purpose of the traveling‐wave‐based measurement scheme described in this paper is to locate a fault on a teed transmission feeder with mixed overhead and underground sections. Simulation results demonstrate that the fault locator can accurately locate all realistic faults, including ones that are high resistance or occur at nonideal points on wave. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Not green enough: a response to the green pope and the green patriarch based on the dark green thought of Thomas Berry

The teachings of the current Pope and the Ecumenical Patriarch of Constantinople are saturated with the green hue of environmental awareness. They have called upon humankind to alter its worldviews and lifestyles to protect the environment. It is our contention that their awareness does not go far enough. It is not green enough. This article argues that the writings of Thomas Berry, Catholic priest, cultural historian, and self-titled ‘geologian’ offer a more appropriate approach, one that is of a darker shade of green that is needed in the face of the current crisis. The essential argument is that human actions will not change until our conceptual framework has been altered and that Berry offers just such a framework for the human future.     

Modelling the dynamics of design error induced rework in construction

Rework that is experienced in construction projects is often caused by errors made during the design process. Factors that contribute to design errors are identified and used to design and develop a systems dynamics model, which is used to simulate a number of practical scenarios that can be used to reduce design errors and rework. The model presented in this paper can enable design and project managers to understand better the process of design documentation and how design errors occur in construction projects.     

Quantifying the causes and costs of rework in construction

Very few construction companies and consulting firms in Australia measure their costs of quality. Consequently, it is difficult for them to prove that systems for preventing quality failures are cost-effective. Although the direct costs of a quality system can be quantified with some accuracy (salaries, costs of documentation, audits, etc.), the corresponding benefits are far more difficult to assess. Indeed quality failures have become an endemic feature of the procurement process in construction and invariably lead to time and cost overruns in projects. Thus, in order to improve the performance of projects it is necessary to identify the causes and costs rework. The research presented in this paper quantifies the causes, magnitude and costs of rework experienced in two construction projects that were procured using different contractual arrangements. The causes and costs of rework projects are analysed and discussed. The findings reveal that the cost of rework for the case study projects was 3.15% and 2.40% of their project contract value. Changes initiated by the client and end-user together with errors and omissions in contract documentation were found to be the primary causes of rework. It is recommended that construction companies and consultant firms (particularly design consultants) implement quality management practices as well as place emphasis on coordinating project documentation during the design development process so that the amount of rework in projects can be reduced or even eliminated.     

Practices,barriers and benefits of risk management process in building services costs estimation: comment

This note is a comment on Mok, C.K., Rao Tummala, V.M. and Leung, H.M. (1997) Practices, barriers and benefits of risk management process in building services cost estimation, Construction Management and Economics, 15 (2), 161–75, which describes research into the risk perceptions and risk management practices of building services engineers in Hong Kong. The note questions statements made in the paper and parts of the research design and data analyses.