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Construction projects are characterised by supply chains with multiple contracts and significant transaction costs. An example of these costs is to be found in the management of project delays. The operationalisation and measurement of transaction costs, especially in the construction context, has hitherto proved difficult. The work reported here is concerned with defining and measuring the resources required for the management of contractual disputes relating to project delays. Its main argument is that concepts from transaction cost economics (TCE) theory (bounded rationality, uncertainty, information asymmetry, and opportunistic behaviour) present serious problems for transaction efficiency. This is exemplified in forensic analysis of construction project delays. Data from twelve case studies are analysed, to reveal that up to 90% of time spent on delay analysis was concerned with searching for and validating information which could, ostensibly, be automatically and reliably captured using digital technologies. This research forms part of a wider study that considers the implications of the identified inefficiencies and makes a case for the exploitation of advances in information technology on the more efficient resolution (or even avoidance) of contractual disputes. It concludes that there is a prima facie case for this, and therefore for the reduction in the transaction costs that relate to the management of construction project delays.

Construction delay claims are a leading cause for disputes in the sector. There are two primary aspects to such disagreements: legal and factual. The focus of this paper is the latter. It identifies, evaluates and ranks the factors that impact the analysis of evidence concerning construction delays. The research method is two-fold, involving content analysis of twenty case studies, that identifies the reasons for difference in expert opinion (or factors), and testing of these findings in a survey questionnaire designed to examine the impact and comprehensiveness of those factors. This method provides a more rigorous assessment than previous studies and therefore a more precise list of variables. It is concluded that the factors can be grouped into two categories: (i) materials and documents and (ii) matters of interpretation. Although both categories are important, the deficiencies in the former are often exploited by the parties and/or legal professionals to generate conflicting results in terms of extension of time entitlements. Incorrect, incomplete, undisclosed and/or unagreed records and procedures are used to generate ambiguity and create opportunities to perpetuate claims and disagreements. The work presented here provides additional support to the proposition that opportunistic behaviour is at the core of factual delay disputes and further evidence that tailored contractual delay protocols such as delay analysis clauses can be an effective aspect of a broader solution.

The reaction rate between two deuterons confined in a harmonic potential is estimated for confinement parameters r0 in the range 0.1-1.0 AA. For reactions in condensed matter to be observable, and in the absence of any new nuclear effect, it is necessary that r0

The 'spherical-solid' model of Almbladh and von Barth (1976) is modified to apply to a dissolved impurity ion in a simple liquid metal. The system of impurity ion and surrounding pseudo-ions is described using Percus-Yevick hard-sphere structure factors, and the electron density is obtained in the density functional scheme. The formalism allows for the relaxation of the liquid metal ions around the impurity ion, and the liquid structure is determined by minimising the free energy of the system. Calculations have been made for Cl, F and O dissolved in liquid solution, and values for the enthalpy of solution have been obtained.

The dynamics of vibrational energy relaxation by collisions in molecular beams and free jet expansions are examined. Within the stochastic approach afforded by the use of the master equation, the incomplete relaxation process may be modelled by assuming a time-dependent transition rate matrix. For non-degenerate levels and weak interactions the state distribution is Boltzmannian if the transition rate matrix is of the Landau-Teller type. The ramifications of this result on the analysis of recent studies of vibrational relaxation in seeded beams is briefly discussed.

An asymptotic form for the structure factor S(k), for large values of k, is obtained for a simple liquid whose molecules interact via a Lennard-Jones type of potential. The result is possibly of interest in the handling of truncated experimental data.

Some twenty series excited in gaseous 80Se2 by lines of the Ar+ laser have been photographed at moderate resolution. They arise from transitions B0u+-X0g+ B1u-X1g and from cross transitions B1u-XOg+ and B0u+-X1g. Measurements in the range 6< nu

Conflicting reports have appeared in the literature concerning the usefulness of the Born-Green equation to determine effective interionic pair potentials in liquid metals from measured structure factors. To elucidate the problem, numerical investigations of the Born-Green equation have been made. These are based on recent structure factor data for sodium and potassium. Using the linearized simultaneous equation method of Waseda and Suzuki (1973), it is found that the equations in real space are ill conditioned. Hence a unique solution cannot be found numerically. However, in Fourier space unique solutions can be determined, but these solutions are temperature dependent. It is concluded that the temperature independent pair potentials for liquid metals which have been obtained from the Born-Green equation are not reliable.

The motion of conduction electrons in a metal in an electric field, scattered by an irregular static potential, is considered; this model is applicable to the resistance due to lattice waves at high temperatures, and to imperfections at any temperature. In §2 the Boltzmann equation is re-derived without the customary perturbation theory, avoiding the usual necessity of averaging over phases of different electron states after repeated small time intervals. The assumption that the scattering centres are distributed at random in the crystal is alone sufficient. The theory is, however, still dependent on assuming that h/τ<

The Boltzmann equation for the distribution of conduction electrons in the presence of a temperature gradient, given by McIrvine, is derived by the method of successive approximation to the equations of motion of the density matrix. Some additional `intercell' scattering terms appear.

The model potential of Hunt and Moiseiwitsch (1970) for the calculation of electron affinity is modified to simulate the potential of a negative ion in a liquid metal. It is found that, as a result of screening by conduction electrons, halide ions bind an additional electron more tightly in a liquid alkali metal than in free space. The method is extended to O-- ions. The theory predicts that O-- ions are electronically stable in liquid sodium, but results for liquid caesium are less conclusive.

The electrical conductivity of electrons moving in a one-dimensional disordered potential is discussed on the basis of the exact expression for the conductivity obtained from the density matrix, and the conductivity evaluated in the limits of weak and of strong scattering potentials. The method depends on a property of electron wave functions in such a potential, noticed by Mott.

It is suggested that a conclusion reached by Springer in 1964 that the perturbation series for the electrical resistivity of liquid zinc converges slowly is incorrect, and arises because the pseudo-potential has been incorrectly treated as an ordinary potential.