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This paper aims to investigate the effect of different doses of gamma radiation on the micromechanical response (hardness properties and creep behaviour) of 96.5Sn-3.0Ag-0.5Cu (SAC305) solder alloys.

SAC305 solder pastes deposited on printed circuit boards (PCBs) were subjected to a reflow soldering process to form soldered samples. The soldered samples were irradiated with a gamma source at different doses (5–50 Gy). Nanoindentation testing was used to determine the hardness properties and creep behaviour after gamma irradiation.

The results showed that the hardness of SAC305 solder alloys gradually increased up to 15 Gy and then gradually decreased to 50 Gy of gamma irradiation. The highest hardness value (0.37 GPa) was observed on SAC305 solder alloys exposed to 15 Gy irradiation. Hardening of SAC305 solder alloy was suggested to be due to the high defect density induced by the gamma irradiation. Meanwhile, exposure to 50 Gy irradiation resulted in the lowest hardness value, 0.13 GPa. The softening behaviour of SAC305 solder alloy was probably due to the evolution of defect size in the solder joint. In addition, the creep behaviour of the SAC305 solder alloys changed significantly with different gamma irradiation doses. The creep rates were higher at a dose of 10 Gy up to a dose of 50 Gy. Gamma irradiation caused the SAC305 solder alloy to become more ductile compared to the non-irradiated alloy. The stress exponent also showed different deformation mechanisms with varying gamma doses.

Research into the micromechanical properties of solder alloys subjected to gamma irradiation has rarely been reported, especially for Sn-Ag-Cu lead-free solder. Thus, this research provides a fundamental understanding of the micromechanical response (hardness and creep behaviour) of solder, especially lead-free solder alloy, to gamma irradiation.

The Journal of Documentation does not normally publish papers on the classification, etc., of specific subjects. An exception has been made in this case, since most of the available examples of faceted classifications are in the field of science and technology and it is felt useful to publish an illustration of the use of this technique for a subject within the humanities. The techniques of faceted classification were applied to the fine arts in a scheme which was designed for use in a college library. Some problems of classifying the literature are discussed, together with the solutions adopted. An excerpt schedule with an alphabetical subject index and some classified examples are provided to illustrate the project.

Bruce Lloyd of the South Bank University reports on an interview with Professor George S. Yip, author of Total Global Strategy: Managing for Worldwide Competitive Advantage. Argues that managers must analyse their industry and identify the specific drivers that affect their operation and development. Leads to the identification of a number of global strategy levers: global market participation; products (global products, or local products); location of the value chain; marketing strategy. Explores critical success factors: a combination of traditional concepts associated with building and maintaining a competitive advantage and creating global capabilities and a global network that can tap into the best resources and expertise available around the world, as well as knowing how to pull it together and use it effectively. Maintains that the greatest challenge for management education all over the world is how to reconcile theory and practice. You must understand what you need to learn, then develop the capability actually to learn it.

Using fuzzy measures and fuzzy integrals, the paper presents a mathematical model of learning which is able to learn through fuzzy information. The characteristics of the model are studied theoretically and in numerical examples, where the model is compared with an ordinary Bayesian learning model. The problem of seeking an extremum of multimodel objective function is given as an example.

The purpose of this paper is to study the effect of gamma-rays on murexide (Mx) dye and its possible use as radiation dosimeters in two different dosimetry systems. The first system depends on the Mx dye as a liquid dosimeter. The second dosimetry system depends also on the same dye but as in a gel form, which is more sensitive to gamma-rays.

The prepared Mx (solutions/gels) have a considerable two peaks at 324 and 521 nm that upon irradiation, the intensity of these peaks decreases with the increasing radiation dose.

The gamma-ray absorbed dose for these dosimeters was found to be up to 2 kGy for the solution samples and 40 Gy for the gels. Radiation chemical yield, dose response function, radiation sensitivity and before and after-irradiation stability under various conditions were discussed and studied.

It is expected that the radiolysis of the Mx dye can be used as radiation dosimeters in two different dosimetry systems; liquid and gel dosimeters. This can be applied in a wide range of gamma radiation practical industrial applications in water treatment, food irradiation dosimeters, radiotherapy and fresh food irradiation and seed production.

Both of the prepared Mx dyes, either as solutions or gel samples, can be facilely prepared from commercially, cheap, safe, available chemicals and suitable for useful applied Mx solutions and gels radiation dosimeters.

Systolic array designs of parallel algorithms for low‐level digital image processing, and in particular the gradient operator, are described. Indicates how, to achieve high performance, a new systolic array can be designed in which all the cells in a double pipeline are interconnected to a system bus. The transputer implementation of the design is also considered and comments and conclusions that relate to the use of the systolic array on transputer networks are given. Subsequently it is shown that the systolic array design can be extended to handle the Prewitt and Sobel operators.

This paper aims to analyse the tack stability measurement readings of thermochromic offset inks. For this purpose, three reversible leuco-dye formed thermochromic inks were used to evaluate their tack. The used inks differ in their activation temperature, colour, drying mechanism, viscosity and chemical content. Thermochromic offset inks differ from conventional inks in formulation and size of colourants due to the presence of the microcapsules.

Printing inks in offset lithography must have sufficient tack so they can be transported from a reservoir onto the substrate. The ink transfer takes place through the ink splitting by inking rollers, printing plate and blanket transport. An IGT Tackoscope device was used to produce the dynamic readings of ink tack as a function of distribution and splitting time. The data can be used for prediction of the ink press stability under controlled settings, such as temperature.

This research explains the temperature and velocity influence on the tack stability measurement readings of thermochromic inks. It also gives an insight of the chemical compounds that dictate the tack measuring reading results.

Development of new printing inks, such as thermochromic printing inks, may affect the printing of different products. The research was conducted due to a lack of available data for the tack of thermochromic inks.

The purpose of this paper is to provide a detailed review of radiation dosimetry techniques based on optical fibre dosimeters. It presents a comprehensive bibliography of the current research activities in the area.

A range of published work on optical fibre radiation dosimeters are presented, with the merits and limitations discussed. Each radiation dosimetry technique is discussed in turn, providing examples of dosimeters using such techniques reviewed. The main focus is on gamma radiation although other radiation dosimeters are considered.

This paper provides information on the wide range of research activity into radiation dosimeters. The dose ranges of these dosimeters are presented, along with the advantages and disadvantages of different dosimetry techniques.

A comprehensive review of published research in the area of solid radiation dosimetry is presented in this paper. It provides an individual with a review of the various techniques used and most recent research in that field.

More significant reductions in residential primary energy consumption and in space heating in particular, can contribute to achieving climate change and energy efficiency objectives. Project information from demonstration projects is now becoming available for highly energy-efficient renovation concepts.

The goal of this research is to understand how owner-occupants can be persuaded to apply far-reaching energy-saving renovations of single-family houses. To this end, the research examines drivers and barriers of owners to adopt highly energy-efficient renovation concepts. Theory on decision processes in innovation diffusion is used, in order to examine the adoption of integrated concepts to achieve high energy performance. Belgian case studies (different building typologies) were examined. Adoption drivers and barriers perceived by owner-occupants are analysed. This leads to improved understanding of characteristics that can persuade future adopters. Possible measures are discussed to overcome barriers in the introduction phase of innovation diffusion, and are illustrated more in detail with a case study. The research shows that especially expectations of improved comfort provide an opportunity for the market entry of integrated concepts. Owners, architects and contractors could benefit from increased attractiveness, competitiveness, affordability and availability of highly energy-efficient renovations. Holistic approaches (stronger coordination and clustered renovation concepts), higher skill competence (education) and improved communication (actor networks, significant economic incentives) are recommended.

Thin films of tellurium dioxide (TeO₂) and indium oxide (In₂O₃) mixtures were investigated for γ‐radiation dosimetry purpose. Samples were fabricated using thermal vacuum evaporation technique. The electrical properties of mixed oxides thin films [(TeO₂)_1−x(In₂O₃)_x, where x=0 and 10 per cent by weight] and their changes under the influence of γ‐radiation were investigated. Samples with contacts having a planar structure showed increase in the values of current with the increase in radiation dose up to a certain dose level. Thin films in the form of pn‐junctions were fabricated with (TeO₂)_1−x(In₂O₃)_x as p‐type material and sulphur as n‐type material. These pn‐junctions exhibited Zener diode behaviour. The current‐voltage characteristics for as‐deposited and γ‐irradiated samples were recorded. The level of response for all the fabricated devices was found to be highly dependent on the composition of the exposed material.