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This study aims to investigate the corrosion behavior of cold-rolled Fe₃₅Ni₂₀C_r12Mn_(28-x)Al_x high-entropy alloys (HEAs) using the potentiodynamic polarization technique in 1 M H₂SO₄ acid. Additionally, the influence of molybdenum (Mo) additions as inhibitors and the effect of variations in cold rolling reduction ratios and Al content on corrosion behavior are examined.

Two cold rolling reduction ratios, namely, 50% (R50) and 90% (R90), were examined for the cold-rolled Fe₃₅Ni₂₀Cr₁₂Mn₂₈Al₅ (Al₅) and Fe₃₅Ni₂₀Cr₁₂Mn₂₃Al₁₀ (Al₁₀) HEAs. Mo inhibitor additions were introduced at varying concentrations of 0.3, 0.6 and 0.9 Wt.%. The potentiodynamic polarization technique was used to evaluate the corrosion rates (CRs) under different experimental conditions.

The results indicate that the addition of 0.3 Wt.% Mo in 1 M H₂SO₄ yielded the lowest CR for both R50 and R90, irrespective of the Al content in the HEAs. However, the highest CR was observed at 0.6 Wt.% Mo addition. Furthermore, increasing the concentration of Al resulted in a corresponding rise in the CR. Comparatively, the CR decreased significantly when the cold rolling reduction ratio increased from R50 to R90.

This research provides valuable insights into the intricate relationship between Mo inhibitors, cold rolling reduction ratio, Al content and the resulting corrosion behavior of Fe₃₅Ni₂₀Cr₁₂Mn_(28-x)Al_x HEAs. The comprehensive analysis of corroded HEAs, including surface morphology, compositions and elemental distribution mapping, contributes to the understanding of the corrosion mechanisms and offers potential strategies for enhancing the corrosion behavior of HEAs.

This study aims to investigate aspects related to the changing trends of the rainfall extremes in the entire Mekong Delta in the period of 32 years (1984-2015) applying rainfall extreme indices. First, the homogeneity tests were applied to assess the quality of observed rainfall data series. The authors, then, investigated three rainfall indices including the number of very heavy rainfall days 20 mm (R20), number of days above 50 mm (R50) and number of days above 100 mm (R100) applying the Mann-Kendall test and Sen’s slope estimate.

First, the homogeneity tests were applied to assess the quality of observed rainfall data series. The authors, then, investigated three rainfall indices including the number of very heavy rainfall days 20 mm (R20), number of days above 50 mm (R50) and number of days above 100 mm (R100) applying the Mann-Kendall test and Sen’s slope estimate.

The results of R20 pointed out that an insignificant upward tendency was found in the coastal provinces, whereas an insignificant downward tendency was also recorded in the inland provinces. Regarding the number of R50, a similar trend to R20 was recorded with five stations slightly increased and five stations slightly decreased. For the number of R100, the results recorded an absence of significant trends over the entire study area. Approximately 58.5% of stations show a slightly decreasing trend, while 41.5% of the remaining stations recorded a slightly increasing trend.

For the number of R100, the results recorded an absence of the significant trends over the entire study area. Approximately 58.5% of stations show a slightly decreasing trend, while 41.5% of the remaining stations recorded a slightly increasing trend. Of note is the fact that the number of R100 occurred more frequently in the northern provinces, which means the northern region is facing a high risk of flooding.

Describes how BMW is investing in new body‐in‐white capital equipment to make a new version of the Mini due out in 2007.

Describes the major production line technologies that are under close scrutiny to manufacture the body shell of the next generation Mini car at BMW Group's Oxford plant in the UK. Technologies to be implemented include a further 160 KUKA robots (most of which will be used for spot welding) and a new generation of control software.

BMW managers and engineers have decided to expand the present body‐in‐white facility at Oxford by a further 15,000m². At the same time they are planning to move some of the present manufacture to the company's plant at Swindon, Wiltshire. This includes various cells to manufacture closures, including doors, tailgate and bonnet assemblies. Already the Cabriolet tailgate assembly has been moved to Swindon. At the same time, engineers plan to introduce a new control standard, product line 2 (PL2), which is already the standard used throughout BMW's manufacturing organization.

Engineers BMW's oxford plant have been upgrading the present r50 control standard into a hybrid version that will be known as R50.1. This work is due to be complete by the end of this year. The new standard, PL2, will be introduced into the new facilities so there will in effect be two standards running in parallel in the works. At the same time the there will be a switch to Siemens S7 software, which will be faster and offer much increased processing power. Following development and work arising out of previous experience, BMW engineers have opted for KUKA KRC2 robots.

The practical implications of the new facilities will allow BMW engineers greater flexibility. Although it has not yet been made public, it is likely the company will introduce a special framing unit that will allow manufacturing engineers to produce more than one version of the mini on the body‐in‐white line.

The work being done at Oxford for the 2007 Mini will incorporate technology and know‐how already developed within the BMW Group to manufacture the 1‐Series and the 3‐Series cars.

This article reports on the results of a survey on how companies listed on the main board of the JSE Securities Exchange SA make a capital investment decision in practice. The respondents to the survey questionnaires provided answers regarding the methods that their companies use to evaluate capital investments, as well as to evaluate mutually exclusive projects. The results suggest that South African companies prefer to use the internal rate of return (IRR) and net present value (NPV) to evaluate capital investments. In addition, there appears to be a correlation between the methods that companies use and the size of their annual capital budget. Finally, a hypothetical problem was presented to the respondents, who were asked to choose between two mutually exclusive projects. Interestingly, the majority of the respondents chose the project which added the least value.

Contends that the management of information services should consider the pricing of information products as a challenge which demands an understanding of economic principles. Illustrates the range of ideas and tools economists offer for the practical development of a price strategy for information products. Uses three scenarios to demonstrate the formulation of different pricing strategies for different information products. The information products used as examples in these scenarios are a CD‐ROM database, a training programme and a report on the involvement of mechanical engineers with the Reconstruction and Development Programme in South Africa.

In July 2002 a new EC Preparations Directive came into force requiring suppliers of preparations to consider the environmental impact of their preparations. The environmental assessment can be made through consideration of the individual substances used in the preparation. A review of additives used in the formulation of metalworking fluids has highlighted that there are a number of substances that give cause for concern, especially surfactants or basefluids that are derivatives of C12‐15 or C13‐15 alcohols, such as ethoxylates, propoxylates and EO/PO copolymers. Some reformulation may be required in order to prevent preparations being classified either as; dangerous for the environment; or as very toxic/toxic/harmful to aquatic organisms; or as may cause long‐term adverse effects in the environment. The new directive will require suppliers of preparations to make available material safety data sheets for preparations classified as dangerous for the environment or for preparations containing at least one dangerous substance at a concentration of = >1 per cent. The new directive will also require suppliers to use new packaging labels for; preparations classified as dangerous for the environment; preparations containing at least one dangerous substance at a concentration of =>1 per cent; and for preparations containing =>0.1 per cent of a substance classified as a sensitiser.

The Minerals and Petroleum Resources Royalty Act (MPRRA) became effective on 1 March 2010. This legislation may have a significant impact on employment, foreign investment and future exploration in the South African mining industry. This article reports on a critical analysis of the MPRRA prior to its implementation in order to identify aspects that may impact adversely on the South African mining industry and would require further research after the implementation of the MPRRA. Based on the findings, the authors recommend that the impact of the level of royalties levied as well as the mechanism to promote downstream beneficiation be researched to establish whether the legislators ought to reconsider these provisions in the light of their impact on the mining industry.

The purpose of this paper is to analyse the advantages of a new interpretation of the geometric disposition of threads within woven fabric structures, and to develop a method of determining the parameters of threads, with reference to each order of their disposition.

Based on the analysis of the geometrical models proposed by Barker and Midgely, by Pierce and by Novikov, the substantiation of the advantages of a stricter model, offered by the authors, for determining the geometric disposition of threads within single layer woven fabric structures with the help of the tangent function is given. This model allows the substantial expansion of the actual bounds of the interval of the order of the geometric disposition of threads in woven fabric structures to 0.2‐9.8.

The tangent function can approximate the crimp height ratio of the warp threads within the woven fabric structure with accuracy within the limits of geometric disposition angle change from 1° to 89°.

The work has applications in the industrial production of woven fabrics.

This research will allow the design of a woven fabric with practically any ratio of crimp height for the warp and weft threads to effectively achieve the required performance characteristics of the cloth.

This paper extends the knowledge of the geometrical characteristics of woven fabric structure, and proposes intelligent methods of determining the parameters of thread cross‐sections in accordance with the orders of the geometric disposition of threads in woven fabric structure.

The purpose of this research is to explore the possibility of integrating women‐centred savings schemes into formal finance systems in order to help such schemes to leverage finance for housing purposes.

The research adopts a case study approach that uses mainly semi‐structured interviews. The case studies involve two savings schemes with their respective supporting organisations and five commercial banks in South Africa.

The case studies show that, if savings systems are flexible and suitable to their needs, women are capable of saving and repaying housing loans. The results also suggest that the accumulated group savings and the savings schemes themselves act as good collateral. However, despite showing interest in involvement in the low‐income sector, banks do not have a financially viable and workable business model to exploit this potential market.

Integrated community housing is essential. Future research is required to determine how good repayment rates could be achieved while maintaining risks at acceptable levels.

For practical purposes, collaboration with intermediary organisations working with women‐centred savings schemes would be a beneficial starting point in linking the savings schemes with formal finance systems.

The paper provides valuable reference material for understanding the gap that exists between what banks currently offer and what poor households require in meeting their housing needs. It may also be useful to researchers and practitioners as a basis for exploring innovative finance models for banks.

The wireless revolution of the last decade has fuelled unprecedented demand for access to radio frequency spectrum in South Africa. For the first time, the Independent Communications Authority of South Africa faces the daunting task of pricing radio frequency spectrum in a transparent and quantitative manner, while allocating the asset within the framework of black economic empowerment.

The purpose of this paper is to illustrate how real options analysis may be applied to achieve the goal of right pricing of radio frequency spectrum. This paper aims to combine theoretical insights with an empirical case study.

Results suggest that the primary price of a licence will vary according to the profit an entity expects to realize, rather than the licence having one fair value price.

Although such a conclusion may be counter‐intuitive to normal business practice, it is particularly relevant in the South African milieu of empowerment and economic participation by all.