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In this work, it is presented a locally conservative multiscale algorithm accounting the mineralization process during the supercritical carbon dioxide injection into a deep saline aquifer. The purpose of this study is to address numerically the geological storage of CO₂ in a highly heterogeneous reservoir, leading with interactions among several phenomena in multiple scales.

This algorithm have features that distinguish it from the presently available solvers which are: (i) an appropriate combination of a coupled transport system solver using a high-order non-oscillatory central-scheme finite volume method and, elliptic numerical approach applying a locally conservative finite element method for Darcy’s law and, (ii) the capability of leading with interactions among several phenomena in multiple scales.

As a result, this approach was able to quantify the precipitation of the carbonate crystals at the solid interface.

In both decorative and industrial applications of gold plating, but even more critically in the latter, accurate measurement of coating thickness is of vital importance to both the manufacturer and the user. To the former, working to increasingly stringent specifications, it may, in extreme cases, mean the difference between profit and loss if an excessive thickness is inadvertently applied due to some change in electrolyte or processing conditions, or if an unduly high average thickness must be used on barrel or vat plated components to ensure a minimum requirement on functional areas. To the user, it can equally mean the difference between operational success and failure of a gold plated part if plating thickness is below specification and the means used for measurement are not sufficiently precise to detect this. Control of coating thickness in gold plating is therefore a matter of vital concern, and never more so than at the present time when, in the face of the spectacular price increases of recent years, and in the virtual absence of viable alternatives to meet the exacting demands of applications in printed circuitry, semiconductor technology and the electronics industry in general, the need for maximum economy in gold usage has become increasingly urgent, as evidenced by the vigorous efforts currently devoted to the development and improvement of selective plating techniques, and the recent interest manifest in the possible replacement of essentially pure gold coatings by alloy deposits of 18 carat and lower where these may be technically acceptable. The present article offers a wide‐ranging survey of methods available for thickness measurement, with particular reference to gold plating, but including also some techniques which, whilst not finding current use, may be of potential interest in this context. This is the second and final part of this article, the first having appeared in Volume 1, Number 1, October (1974).

Modern industry and domestic users continue to demand increasing quantities of coated products. Since price, performance and appearance are all dependent upon the thickness of these coatings, it is mandatory to measure thicknesses as fast, as accurately and as economically as possible. Modern technology has largely solved the mechanics, or more correctly the electronics, of the actual measuring process, but now most ordinary users find problems in how best to use the results for the greatest overall benefit. The Beta Backscatter method of measurement applied to the production and use of printed circuits is taken as an example of what can be done with a little more knowledge, perhaps a little beyond that of simple coating thickness measurement.

COATINGS are applied for a wide variety of reasons. These include atmospheric protection, appearance, performance, cost (coated material is often cheaper than the solid) and so on. Methods of application very much depend upon the coating being applied: spraying, dipping, electrolysis, chemical treatment and conversion, are all common methods. No matter what the coating or method of application, the monitoring and control of thickness is mandatory and if that control can be accomplished non‐destructively there are many additional advantages.

To solve the problem, a mathematical model is proposed; it relies on a directed acyclic graph (DAG), in which arcs are used to indicate whether a pair of appointments can be assigned to the same route or not (and so to the same care worker). The proposed model aims at minimizing the personnel required to meet daily demand and balancing workloads among the workers while considering the varying traffic patterns derived from traffic congestion.

This paper aims at providing solution approaches for addressing the problem of assigning care workers to deliver home health-care (HHC) services, demanding different skills each. First, a capacity planning problem is considered, where it is necessary to define the number of workers required to satisfy patients' requests and then, patients are assigned to the care workers along with the sequence followed to visit them, thus solving a scheduling problem. The benefits obtained by permitting patients to propose multiple time slots where they can be served are also explored.

The results indicate that the problem can be efficiently solved for medium-sized instances, that is, up to 100 daily patient requests. It is also indicated that asking patients to propose several moments when they can receive services helps to minimize the need for care workers through more efficient route allocations without affecting significantly the balance of the workloads.

This article provides a new framework for modeling and solving a HHC routing problem with multiskilled personnel. The proposed model can be used to identify efficient daily plans and can handle realistic characteristics such as time-dependent travel times or be extended to other real-life applications such as maintenance scheduling problems.

The Beta Backscatter Coating Thickness Gauge has been a very well used “tool” in printed wiring production for many years. The increased requirement to more closely control the quality and cost of high priced materials and processes has been met by instrument developments utilising microprocessors, not only for measurement but also for instrument, operator and results evaluation. Despite this, the instrumentation will only deliver the correct results if given correct information in the first place, thus, the operator must know a little of the preceeding coating process or at least be given the relevant and correct information. This paper describes the importance of the substrate material and the density of the coating material when measuring coating thickness.

Any discussion, book or article, on the subject of non‐destructive testing usually refers to eddy current measurement techniques in one of its forms. Eddy currents, or use of eddy currents, is perhaps one of the fundamental N.D.T. techniques. Perhaps because theoretically such techniques have much to offer.

Most of the basic requirements for the manufacture of printed wiring are, of course, well known; so much so that literally hundreds of companies or divisions of larger companies are formed annually to produce these products. However, a high percentage of such companies fail, especially when new specifications are introduced or existing specifications are adhered to by the purchasing authority. There is a wide diversity of reasons for failure of printed wiring products to meet the requirements of quality and performance. Since some of these can be attributed to coating thickness and/or coating porosity, it is therefore the purpose of this article to outline the ways and means to control these parameters.

Since the 1974 oil crisis and the subsequent escalation of organic finishing materials, there has been a considerable change in the attitude towards investment in measurement/control instrumentation. From the supplier of coated products point of view there is the realisation that the investment is more quickly recovered, with the bonus of a better and more reproducible product which is easily cost controlled. The purchaser of coated products can now be confident that he/she is receiving the product which has been paid for by the receipt of a hard copy record of the results and results evaluation.

The advantages in the use of microprocessors are by now very well documented and these devices are used the world over in a multitude of roles. In many cases, they are underused regarding their design capacity, but still have the large advantage of enabling manufactering time and complexity to be much reduced keeping costs down. Thus we even see them used in relatively simple household appliances and childrens toys — all of which has contributed in the past to demand exceeding supply and subsequent cost escalation. Use of a microprocessor does not of itself, necessarily produce a better system, other than reducing manufacturing complexity. The device must be built into a system able to use if efficiently and the whole must be programmed correctly for the planned work. In jargon: ‘the hardware must be able to use the software and the software must be designed for the requirement’.