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Evaluates the applicability of ultrasonic sensors in a welding environment and reports on experimental measurements carried out with a sensory head containing ultrasonic transducers with different frequencies. Analyses the effects on the sensors of factors such as noise, temperature and shielding gas flow and concludes by suggesting appropriate protective measures for the sensors for them to operate effectively in a welding environment.

A mechanical and microstructural study was performed of 43/43/14 tin/lead/bismuth solder. This alloy melts lower than the commonly used tin/lead solders and therefore holds promise as a useful material in two‐step soldering processes or in processes with thermally sensitive components. Mechanical testing of 43/43/14 tin/lead/bismuth showed a strength comparable to that of tin/lead solders but increased creep rate. Microstructural analysis (scanning electron microscopy/energy dispersive X‐ray) exhibited the same mechanism of fatigue as for tin/lead solders, viz., heterogeneous coarsening. Thermocyclic fatigue demonstrated that the long‐term reliability of 43/43/14 tin/lead/bismuth is comparable to that of tin/lead solders.

This paper aims to comprehend organizational transformation (OT) as a permanent, continuous and iterative system, which integrates large transformations that, in turn, require smaller, additional transformations. For OT implementation, a conceptual model is proposed, called the four orders of OT.

Case study with a qualitative approach, used critical incident interviews, which were applied to describe both successful and unsuccessful events. Participants were chosen by convenience, and information was processed with Nvivo software.

The Colombian family holding studied was founded in 1974, and in its 47 years of existence, has implemented important transformations in its three companies. These showcase the four types of OT proposed, although third order support has been applied most often. The events that triggered said transformations are mainly of exogenous character, and broad responsibility was found on both the upper management and work team levels for implementation processes. This was also found for the indicator use and the various planning approaches used, depending upon the transformation type.

Future research is required, so as to refine and validate the conceptual OT model proposed in other types of companies and development contexts. The proposed construct permits company managers to design and more efficiently manage transformations, while satisfying the diverse orders proposed in the theoretical model.

An integrative conceptual model called “the four orders of OT” is proposed and validated in a Colombian family businesses group, which is composed of three companies.

The purpose of this research paper was to investigate the use of methanolic extract of Salvia hispanica (S. hispanica) as a green corrosion inhibitor for bronze in a simulated acid rain solution.

Extract of S. hispanica was used as a green corrosion inhibitor for bronze in simulated acid rain solution. Electrochemical techniques such as potentiodynamic polarization curves, electrochemical impedance spectroscopy and electrochemical noise were used. Parameters such as polarization, charge transfer and noise resistance (Rp, Rct and Rn, respectively) were calculated.

Results showed that the extract acts as a good, anodic type of inhibitor. The inhibitor efficiency increased with increasing its concentration up to 400 ppm, decreasing beyond this concentration. Efficiency also increased with an increase in the immersion time. The inhibition was due to the adsorption of components found in the S. hispanica extract following a Langmuir adsorption isotherm.

S. hispanica extract can be used as a corrosion inhibitor for bronze in acid rain solution.

This study provides new information on the inhibition features of S. hispanica under specific conditions. This eco-friendly inhibitor could find applications to protect bronze exposed to polluted urban atmospheres.

An empirical study was conducted to determine the thermal fatigue behaviour of 1.27 mm pitch, J‐bend and gullwing surface mount solder joints, manufactured with four low‐temperature solders. Selected solder alloys were: 58Bi‐42Sn (wt %), 43Sn‐43Pb‐14Bi, 52ln‐48Sn and 40ln‐40Sn‐20Pb. Accelerated thermal cycling was used in conjunction with metallographic analysis and mechanical (pull) strength measurement to test their behaviour. The relative merit of each solder composition was determined by comparing it with 63Sn‐37Pb solder, subjected to identical testing conditions. The strength decreased linearly with increased number of thermal cycles for gullwing solder joints of all four solder alloys. The fatigue lifetime was relatively longer for 58Bi‐42Sn and 40ln‐40Sn‐20Pb than for other alloys, but significantly lower than that obtained with 63Sn‐37Pb solder. No discernible degradation of strength was observed with the J‐bend solder joints of any solder alloy, even after the completion of 6000 thermal cycles. Thermal fatigue resistance of the latter joints was attributed to a more favourable coefficient of thermal expansion (CTE) mismatch. Solder joint cracking occurred only in gullwing components soldered with 52ln‐48Sn, 40ln‐40Sn‐20Pb and 43Sn‐43Pb‐14Bi alloys, after 1000 or 2000 thermal cycles. The crack initiated on the outside surface of the solder fillet, and appeared to propagate through both phases of the microstructure. The stress‐induced heterogeneous coarsening of the microstructure was evident only with 43Sn‐43Pb‐14Bi solder, although not as prevalent as that usually observed with eutectic Sn‐Pb solder. Fatigue cracks were absent from solder joints of 58Bi‐42Sn and 63Sn‐37Pb alloys.

A series of composite solders in 63/37 Sn/Pb was prepared: Cu₆ Sn₅ (10, 20, 30 wt%); Cu₃ Sn (10, 20, 30 wt%); Cu (7.6 wt%); Ag (4 wt%); and Ni (4 wt%). These composite solders were prepared by two procedures: (A) admixture with solder paste; and (B) admixture with molten solder. The original particulates and the final composite solders were analysed and characterised by SEM (scanning electron microscopy) EDX (energy dispersive X‐ray), and ESCA (electron spectroscopy for chemicals analysis); or XPS (X‐ray photoelectron spectroscopy). A variety of morphological characterisations, intermetallics and porosities were noted. Good wetting was noted in all cases, and porosity was greater for method (A). The particulates all exhibited excellent binding to the solder matrix.

The paper considers model‐based management and, based on it, proposes a heuristic‐based management. This paper aims to assert that heuristic‐based management, for complex systems, a process of free variation, of pairs of models and actions – called organisational strategies, maximizes the chances of improving the system's performance in open environments.

A conception of complex systems are introduced and characterized as open and self‐organising systems. Then, the proposal to heuristically use pairs of models and actions, called organisational strategies, to manage social systems based on evolutionary thought is supported. Subsequently, a computational experiment is proposed to show that, even in a simple framework, variation processes are required.

The paper shows that two processes may be required to preserve self‐organising systems. This finding indicates that variation and selection processes, related to evolutionary thought, are necessary for managers to deal with complex systems interacting with complex environments. Finally, it is shown that, even in simple computational environments, variation may be required.

The paper is the first part of an ongoing research agenda on the subject of heuristic‐based management and only refers to variation processes.

The paper links complex systems theories to evolutionary thought. It also relates principles of cybernetics to those of game theory. The proposal has been formalized based on these relations, and has been called heuristic‐based management. Principles first developed in information theory, organisational cybernetics, and evolutionary thought are used so that a complex system can be effective when interacting with a complex environment.

Composite solders were prepared by mechanically dispersing 15v% of Cu or Ag particles into the eutectic Sn‐3.5Ag solder. The average sizes for the nominally spherical Cu and Ag particles were 6 and 4 microns, respectively. Two different processing methods were used to prepare the composite solders: blending the powdered particles with solder paste, and adding particles to the molten solder at 2808C. The composite solders were characterised by studying the morphology, size and distribution of the reinforcing phase. Particular interest and emphasis are given towards the modifications of the reinforcements during the reflow process. Microstructural features and chemical analysis of the composite solders were studied using optical and scanning electron microscopy (SEM), and energy dispersive x‐ray (EDX) analysis. The effect of reflow and isothermal ageing on the microstructure as well as the morphological changes in the interfacial IM layer of the composite solders were extensively analysed. A mechanism for IM layer growth is proposed for solid state isothermal ageing.

This paper seeks to present a proposal to change the form in which knowledge is produced in Colombia.

Discusses the key issue – to transform the way in which the production of knowledge is currently taking place at the university level.

To be able to increase the production of knowledge in this country there is a need to create bonds among industrial, governmental, and academic institutions. It is believed that this can be done by the development of a system capable of continuously forming researchers at a doctoral level.

The paper puts forward a proposal for the construction of such a system based on the developments of organizational cybernetics. The proposal is based on the concept of autonomy which is crucial to solve this problem.

The purpose of this paper is to examine the level of understanding between an Australian university and its offshore partner institution, on quality assurance. It attempts to highlight the dynamics of quality assurance policy implementation within and across institutions for an offshore degree.

The study used interviews as the research method to gather data from the Business school of a university that is a major exporter of higher education degrees and its offshore business partner, a business school of a private university college in Malaysia.

The findings show that gaps exist in the current practices of quality assurance measures in Malaysia. In addition, top‐level management from both sides of the exchange believe that the university should bear the overall responsibility for quality assurance. However, the findings also reveal that such heavy reliance on the university for quality assurance might not be healthy, especially when the university's own policy implementation is suffering internal problems.

For governments and various agencies the insights in the paper will be useful in creating better policy. At an institutional level, the findings will assist in the formulation and implementation of such policies.

This paper will be useful to stakeholders in the offshore education industry. It provides an insight into the regulatory and auditing practices commissioned by the government and highlights the various gaps and challenges in quality assurance policy.