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This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/eb013770. When citing the article, please cite: C.P. Harris, (1974), “WHAT PRICE CONSUMERISM?”, International Journal of Social Economics, Vol. 1 Iss: 3, pp. 261 - 267.

THE new President of the Library Association, a handsome portrait of whom appears in the December Library Association Record, brings to the office the influences of a career of fine public service. We, in common with every journal that speaks to and for librarians, assure him of loyalty and congratulate ourselves on this addition to the roll of distinguished men who have served librarianship. The Record is wise in reminding us that we are more than a librarians' association and the regular election of men of affairs as presidents is a policy that used to be followed and should now be continued. The policy need not exclude in normal circumstances an alternate librarian president.

This paper describes a study into the development of an optimum fabrication process for the batch production of thick film titanium oxide‐PVC pH electrodes. Multi‐factorial experimental plans are used to explore the effect of fabrication parameters on the average sensitivity of sensors and their batch variability. Analysis of the results indicates that a number of the factors have a small effect on the sensitivity. Factors of particular importance are identified and TiO₂ in a PVC binder is examined in detail. The optimal values for these fabrication values are identified and examined. Mechanisms for the experimentally observed sub‐Nernstian responses and immersion‐time variations in sensor behaviour are discussed.

The paper presents an extension to previous work on modelling AC losses in high‐temperature superconducting tapes as a highly non‐linear diffusion process. Following successful formulation for a bulk superconductor the presence of silver in a tape has now been included, using a “sandwich” model, to represent more realistically the practical arrangement. The results of the extended 1‐D model are included and a new 2‐D scheme is described using finite difference formulation. Effects of non‐linearity are emphasised.

I have worked in libraries for nearly three decades and have adopted as a maxim “the right books in the right hands at the right time”. For a variety of reasons it is not always possible to have the “right book” as such and a good working substitute is often a photocopy. One major area where photocopies are a practical means of provision is in our student collection, the Reserve Collection, where one or at most three copies are held. This makes available information which should be read at an appropriate place in a course. We believe that in the future a financial penalty will be incurred and will be hard to meet. This type of copying will fall under “systematic single copying”, an iniquitous catch‐all phrase. In the past we have taken pride in the fact that with efficient management by the library, co‐operation with academic staff and good sense from our students we could provide whatever was needed with a high level of certainty. The effect of militant copyright holders if unchecked will seriously impede us in achieving our aims and this will be one more factor in turning our graduates from people with wide information horizons into narrowly trained technocrats. We must ask if this is in the national interest. We are and will be in intense competition with other nations. Wrong use of copyright alone will not create this adverse state; it is but one element along with the high rate of inflation in books and journals, VAT at above zero rating, uncritical publication, repetitive publication, increasingly adverse staff/student ratios, bureaucratic dominance, policies that enforce a blinkered approach and deny imagination and so on.

The purpose of this paper is to fabricate the scaffolds with different pore architectures using additive manufacturing and analyze its mechanical and biological properties for bone tissue engineering applications.

The polylactic acid (PLA)/composite filament were fabricated through single screw extrusion and scaffolds were printed with four different pore architectures, i.e. circle, square, triangle and parallelogram with fused deposition modelling. Afterwards, scaffolds were coated with hydroxyapatite (HA) using dip coating technique. Various physical and thermo-mechanical tests have been conducted to confirm the feasibility. Furthermore, the biological tests were conducted with MG63 fibroblast cell lines to investigate the biocompatibility of the developed scaffolds.

The scaffolds were successfully printed with different pore architectures. The pore size of the scaffolds was found to be nearly 1,500 µm, and porosity varied between 53% and 63%. The fabricated circular pore architecture resulted in highest average compression strength of 13.7 MPa and modulus of 525 MPa. The characterizations showed the fidelity of the work. After seven days of cell culture, it was observed that the developed composites were non-toxic and supported cellular activities. The coating of HA made the scaffolds bioactive, showing higher wettability, degradation and high cellular responses.

The research attempts highlight the development of novel biodegradable and biocompatible polymer (PLA)/bioactive ceramic (Al₂O₃) composite for additive manufacturing with application in the tissue engineering field.

This paper aims to present a multi-fidelity surrogate-based optimization (MFSBO) method for computationally accurate and efficient design of microfluidic concentration gradient generators (µCGGs).

Cokriging-based multi-fidelity surrogate model (MFSM) is constructed to combine data with varying fidelities and computational costs to accelerate the optimization process and improve design accuracy. An adaptive sampling approach based on parallel infill of multiple low-fidelity (LF) samples without notably adding computation burden is developed. The proposed optimization framework is compared with a surrogate-based optimization (SBO) method that relies on data from a single source, and a conventional multi-fidelity adaptive sampling and optimization method in terms of the convergence rate and design accuracy.

The results demonstrate that proposed MFSBO method allows faster convergence and better designs than SBO for all case studies with 49% more reduction in the objective function value on average. It is also found that parallel infill (MFSBO-4) with four LF samples, enables more robust, efficient and accurate designs than conventional multi-fidelity infill (MFSBO-1) that only adopts one LF sample during each iteration for more complex optimization problems.

A MFSM based on cokriging method is constructed to utilize data with varying fidelities, accuracies and computational costs for µCGG design. A parallel infill strategy based on multiple infill criteria is developed to accelerate the convergence and improve the design accuracy of optimization. The proposed methodology is proved to be a feasible method for µCGG design and its computational efficiency is verified.

In this paper, a superconvergent patch recovery method is proposed for superconvergent solutions of modes in the finite element post-processing stage of variable geometrical Timoshenko beams. The proposed superconvergent patch recovery method improves the solution speed and accuracy of the finite element analysis of a curved beam. The free vibration and natural frequency of the beam were considered for studying forced vibrations and structural resonance. Beam vibration mode analysis was performed for high-precision vibration mode solutions and frequency values. The proposed method can be used to compute beam vibration modes of beams with different shapes and boundary conditions as well as variable cross sections and curvatures. The purpose of this paper is to address these issues.

An adaptive method was proposed to analyse the in-plane and out-of-plane free vibrations of the variable geometrical Timoshenko beams. In the post-processing stage of the displacement-based finite element method, the superconvergent patch recovery method and high-order shape function interpolation technique were used to obtain the superconvergent solution of mode (displacement). The superconvergent solution of mode was used to estimate the error of the finite element solution of mode in the energy form under the current mesh. Furthermore, an adaptive mesh refinement was proposed by mesh subdivision to derive an optimised mesh and accurate finite element solution to meet the preset error tolerance.

The results computed using the proposed algorithm were in good agreement with those computed using other high-precision algorithms, thus validating the accuracy of the proposed algorithm for beam analysis. The numerical analysis of parabolic curved beams, beams with variable cross sections and curvatures, elliptically curved beams and circularly curved beams helped verify that the solutions of frequencies were consistent with the results obtained using other specially developed methods. The proposed method is well suited for the mesh refinement analysis of a curved beam structure for analysing the changes in high-order vibration mode. The parts where the vibration mode changed significantly were locally densified; a relatively fine mesh division was adopted that validated the reliability of the mesh optimisation processing of the proposed algorithm.

The proposed algorithm can obtain high-precision vibration solutions of variable geometrical Timoshenko beams based on more optimized and reasonable meshes than the conventional finite element method. Furthermore, it can be used for vibration problems of parabolic curved beams, beams with variable cross sections and curvatures, elliptically curved beams and circularly curved beams. The proposed algorithm can be extended for application in superconvergent computation and adaptive analysis of finite element solutions of general structures and solid deformation fields and used for adaptive analysis of more complex plates, shells and three-dimensional structures. Additionally, this method can analyse the vibration and stability of curved members with crack damage to obtain high-precision vibration modes and instability modes under damage defects.

The investigation uses design of experiments (DOE) approach to determine the optimal parameters of photo resist (PR) coating process for photolithography in wafer manufacturing.

Plans of experiments via nine experimental runs are based on the orthogonal arrays to determine the optimum factor condition. In this study, the mean thickness and the uniformity of thickness of the PR are adopted as the quality targets of the PR coating process. This partial factorial design of the DOE method provides an economical and systematic method of determining the optimal process parameter.

A model for the mathematical prediction of the mean thickness and the uniformity of thickness for the PR has been developed in terms of the PR temperature, the chamber humidity, the spinning rate, and the dispensation rate by means of the DOE method. The PR temperature and the chamber humidity are found to be the most significant factors in both the mean thickness and the uniformity of thickness for a PR coating process.

This analysis is valid of dynamic dispensing of the specific type of PR with constant material properties and applying onto a wafer size of eight inches.

A systematic method has been developed to find suitable combinations of process parameters; hence, the traditional approach such as the trial‐and‐error method that is very time‐consuming can be avoided. Furthermore, the efficiency of designs the parameter and the quality of the products are greatly improved.

This approach can be easily applied to design an optimal parameter setting to meet various requirements of different types of products.

The purpose of this study is to develop a novel comprehensive three-dimensional computational model to predict the transient thermal behavior and residual stresses resulting from the layer-by-layer deposition in the direct metal laser sintering process.

In the proposed model, time integration is performed with an implicit scheme. The equations for heat transfer are discretized by a finite volume method with thermophysical properties of the metal powder and an updated convection coefficient at each time step. The model includes convective and radiative boundary conditions for the exposed surfaces of the part and constant temperatures for the bottom surface on the build plate. The laser source is modeled as a moving radiative heat flux along the scanning pattern, while the thermal gradients are used to calculate directional and von Mises residual thermal stresses by using a quasi-steady state assumption.

In this study, four different scanning patterns are analyzed, and the transient temperature and residual thermal stress fields are evaluated from these patterns. It is found that the highest stresses occur where the laser last leaves off on its scanning pattern for each layer.

The proposed model is designed to capture the layer-by-layer deposition for a three-dimensional geometry while considering the effect of the instantaneous melting of the powder, melt pool, dynamic calculation of thermophysical properties, ease of parametrization of various process parameters and the vectorization of the code for computational efficiency. This versatile model can be used for process parameter optimization of other laser powder bed fusion additive manufacturing techniques. Furthermore, the proposed approach can be used for analyzing different scanning patterns.