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This paper aims to present the details of a study undertaken to develop an energy-based time equivalent approach to obtain the fire resistance ratings (FRRs) of light gauge steel frame (LSF) walls exposed to realistic design fire curves.

The energy-based time equivalent method was developed based on the performance of a structural member exposed to a realistic design fire curve in comparison to that of the standard fire time – temperature curve. The FRR predicted by the energy-based method for LSF wall configurations exposed to both rapid and prolonged fires were compared with those from fire design rules and finite element analyses (FEA).

The proposed energy method can be used to obtain the FRR of LSF walls in case of prolonged fires and cannot be used for rapid fires as the computed FRRs were higher than the results from FEA and fire design rules due to the influence of thermal bowing and its magnification effects at a high temperature gradient across the studs for rapid fires.

The energy-based time equivalent method was developed based on equal fire severity principles. Three different wall configurations were considered and exposed to both rapid and prolonged fires. The FRR obtained from the energy-based method were compared with fire design rules and FEA results to assess the use of the energy-based method to predict the FRR of LSF walls.

Preface The functions of business divide into several areas and the general focus of this book is on one of the most important although least understood of these—DISTRIBUTION. The particular focus is on reviewing current practice in distribution costing and on attempting to push the frontiers back a little by suggesting some new approaches to overcome previously defined shortcomings.

The purpose of this research is to explore the effect of time delay on the perception of environmental risks beyond time discounting, and thus provide a reference for effective communication related to environment and environmental risks.

Ten risk scenarios across four time delay conditions were designed. Computer program randomly presented different risk scenarios to student subjects. Risk perception was measured through equivalent certain loss elicited by bi-section method. In all, 50 students from Harbin Institute of Technology Shenzhen Graduate School participated in the experiment.

Time delay makes the subjects optimistic toward environmental risk with the exclusion of time discounting. The more distant in time the occurrence of an environmental risk, the less in intensity subjects will perceive it as a severe threat. Also, there is a noticeable difference in environmental risk perception between males and females.

This tentative research focusses on exploring the existence of time delay effect on environmental risk perception. Only student subjects are recruited for this research. Future studies are needed to extend the population to people of different backgrounds in order to generalize the finding.

Current ethical appeal of zero social discount rate is unlikely to be effective. Time delay effect in people's environmental risk perception should be acknowledged. Such an acknowledgement is the basis of trust in risk communication. Communication effort needs to address this time delay effect to make people alert to long-term environmental risks, and eventually change their environmental behaviors.

The explorative research represents the first attempt to investigate the effect of time delay on environmental risk perception when time discounting is excluded. It suggests a new direction to understand public optimism toward delayed environmental risks, and reluctance to take proactive actions, and thus offers a new insight into related communication efforts.

The goal of the paper is to introduce a new method of obtaining equivalent dynamic model of electromagnetic field quantities. Proposed algorithm allows approximation of the frequency and step response by a simple inertial element model, with adjustable rank and delay. The values of the model parameters may be also used to describe the dynamics of considered system.

The dynamics of interesting field quantity in certain space location may be represented by an equivalent model of inertial element. Parameters of the model are identified using the solution of the problem in quasi‐stationary conditions for very limited number of excitation frequencies. These solutions are further used to build a matching approximation of real frequency response function (FRF).

The proposed method allows fast approximation of transient states of linear vector field. It may be useful with fast and relatively precise estimation of dynamic parameters of the electromagnetic field, e.g. in screening and eddy current problems.

The main limitation of the method is the assumption of linearity of the problem. However, many practical tasks similar to the examples presented in the paper can be considered highly linear.

The main advantage of the method is that it allows fast estimation of the field dynamics without either solving the problem for whole range of frequencies or computing the transient state in time domain. It does not need the access to the original mass and stiffness matrices. Therefore, it may be used with commercial FEM software, which usually restricts access to its internal data.

The method is based on well known concept of moments, but the use of existing stationary FEM solutions for approximating transient states is a novel approach. Proposed procedure may be easily automated for the simulation environments with scripting capabilities.

The purpose of this paper is to address unsteady heat conduction in two subsets of ordinary bodies. One subset consists of a large plane wall, a long cylinder and a sphere in one dimension. The other subset consists of a short cylinder and a large rectangular bar in two dimensions. The prevalent assumptions in the two subsets are: constant initial temperature, uniform surface heat flux and thermo-physical properties invariant with temperature. The engineering applications of the unsteady heat conduction deal with the determination of temperature–time histories in the two subsets using electric resistance heating, radiative heating and fire pool heating.

To this end, a novel numerical procedure named the enhanced method of discretization in time (EMDT) transforms the linear one-dimensional unsteady, heat conduction equations with non-homogeneous boundary conditions into equivalent nonlinear “quasi–steady” heat conduction equations having the time variable embedded as a time parameter. The equivalent nonlinear “quasi–steady” heat conduction equations are solved with a finite difference method.

Based on the numerical computations, it is demonstrated that the approximate temperature–time histories in the simple subset of ordinary bodies (large plane wall, long cylinder and sphere) exhibit a perfect matching over the entire time domain 0 < t < ∞ when compared against the rigorous exact temperature–time histories expressed by classical infinite series. Furthermore, using the method of superposition of solutions in the convoluted subset (short cylinder and large rectangular crossbar), the same level of agreement in the approximate temperature–time histories in the simple subset of ordinary bodies is evident.

The performance of the proposed EMDT coupled with a finite difference method is exhaustively assessed in the solution of the unsteady, one-dimensional heat conduction equations with prescribed surface heat flux for: a subset of one-dimensional bodies (plane wall, long cylinder and spheres) and a subset of two-dimensional bodies (short cylinder and large rectangular bar).

Three separate but related streams of productivity research have recently appeared in the accounting and distribution literature. One stream has been concerned with the conceptual approach to developing productivity measurement systems. A second stream has argued that accounting‐oriented information systems have been ineffective in meeting the productivity reporting requirements of the marketing and distribution functions. The third stream has applied the conceptual approaches of the first stream to the problems cited in the second to produce a more effective distribution productivity measurement and reporting system. This article is a continuation of the third line of research. Specifically, the article describes a methodology for measuring productivity changes in distribution with the use of specific management accounting tools.

During the 1990s the value to an intending professional accountant of undertaking a period of liberal (general) studies was promoted internationally by a number of individuals and organisations, including the International Federation of Accountants (IFAC) and the New Zealand Institute of Chartered Accountants (the “Institute”). The Institute significantly changed its admissions policy for Chartered Accountants in 1996 and one change was to require four years of degree level study with a compulsory liberal studies component. This study surveys the perceptions of New Zealand accounting practitioners on the impact of this compulsory liberal component. The results of this study demonstrate that there is little support from accounting practitioners for IFAC’s claim that liberal education “can contribute significantly to the acquisition of professional skills”, including intellectual, personal and communication skills. In addition, the majority of respondents did not perceive any improvements in the professional skills of the staff that had qualified under the Institute’s current admissions policy. However, any perceived improvements were mainly attributed to the Institute’s admissions policy change. Notwithstanding the lack of support for the assertion that liberal education develops professional skills, there is a strong belief by respondents in the value of liberal education for intending professional accountants.

The subject of part‐time work is one which has become increasingly important in industrialised economies where it accounts for a substantial and growing proportion of total employment. It is estimated that in 1970, average annual hours worked per employee amounted to only 60% of those for 1870. Two major factors are attributed to explaining the underlying trend towards a reduction in working time: (a) the increase in the number of voluntary part‐time employees and (b) the decrease in average annual number of days worked per employee (Kok and de Neubourg, 1986). The authors noted that the growth rate of part‐time employment in many countries was greater than the corresponding rate of growth in full‐time employment.

The radiological consequences on the population of a borax accident in 1994 in the Tammuz 2 nuclear reactor have been postulated. Dose equivalents resulting from the atmospheric release of radionuclides during the accident have been estimated for distances ranging from the exclusion zone to 100km from the reactor. Gamma submersion, beta submersion doses from the plume, inhalation doses and surface exposure doses have been estimated for various exposure times. Dose equivalents estimated for the site boundary for an exposure time of 24 hours were 1.42 − 10mSv. Accordingly, it seemed that the consequences of the accident on the population living around Tuwaitha site could only take the form of stochastic radiation, such as the induction of cancers, and heredity.