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International audience; In situ electrochemical impedance spectroscopy (EIS) and ex situ X-ray photoelectron spectroscopy (XPS) measurements on electrogenerated zirconium oxide films on zirconium (Zr/ZrO2) were used to quantify the oxide film thickness and resistivity profiles through the oxide. The EIS analysis presented here takes advantage of the high-frequency domain at which the constant-phase element (CPE) behavior of the oxide film reverts to a capacitive response and the Cole-Cole representations of the complex capacitance to extract the high-frequency capacitance of the oxide film without reference to the nature of the timeconstantdistribution within the oxide film. The film thickness of the ZrO2 samples measured from the high-frequency capacitance of EIS were in good agreement with the thickness obtained from XPS. Moreover, the EIS analysis presented is based on the use of the integral solution of the power law model, which allows to obtain in one single EIS experiment, both the film thickness and the resistivity profile in the ZrO2 film. This work suggests a convenient graphical method to extract film properties and serves tovalidate a key assumption of the power-law model for interpretation of CPE parameters in terms of physical properties.

The authors gratefully thank the sponsorship of Fundação para a Ciência e Tecnologia through the Strategic Project UID/EMS/00667/2013 – UNIDEMI. Axiomatic Design classifies designs into three basic types: uncoupled, decoupled and coupled. The first type encompasses the ideal designs, where independence is always ensured, the second includes the designs where independence can be achieved using the right sequence to fine-tune the design parameters as to satisfy the given set of functional requirements, while the last comprises designs for which independence can never be achieved. Usually, coupled designs are avoided and designers are encouraged to redesign their solutions until an uncoupled or a decoupled one is achieved. Nevertheless, coupled solutions are often hard to avoid. This paper discusses this issue and uses a simple graphical example on how to adjust either the functional requirements or the design parameters of a 2-FR, 2-DP coupled design that is regarded as being uncoupled, as to attain the minimum information content. publishersversion published

Geometric dimensioning and Tolerancing (GDT) constitutes the dominant approach for design and manufacture of mechanical parts that control inevitable dimensional and geometrical deviations within appropriate limits. The stack up of tolerances and their redistribution without hampering the functionality is very important for cost optimization. This paper presents a methodology that aims towards the systematic solution of tolerance stack up problem involving geometric characteristics.Conventional tolerance stack up analysis is usually difficult as it involves numerous rules and conditions. The methodology presented i.e. generic capsule method is straightforward and easy to use for stack up of geometrical tolerances of components and their assembly using graphical approach. In the work presented in this paper, angularity tolerance has been considered for illustration of the methodology. Two approaches viz. Worst Case (WC) and Root Sum Square (RSS) have been used. An example of dovetail mounting mechanism has been taken for purpose of stack up of angularity. Based on the stacked tolerance, it can be verified with the design tolerance of the assembly. Based on the comparison, designer has to reassign the appropriate tolerances to fulfil the functionality if required. If the stacked tolerance is as per designer requirement, then reallocation of tolerances on individual components should be done. Costs versus tolerance data are available for each component. With optimization technique, the optimized cost has been calculated for the assembly.

Geometric dimensioning and Tolerancing (GDT) constitutes the dominant approach for design and manufacture of mechanical parts that control inevitable dimensional and geometrical deviations within appropriate limits. The stack up of tolerances and their redistribution without hampering the functionality is very important for cost optimization. This paper presents a methodology that aims towards the systematic solution of tolerance stack up problem involving geometric characteristics.Conventional tolerance stack up analysis is usually difficult as it involves numerous rule and conditions. The methodology presented i.e. generic capsule method is straightforward and easy to use for stack up of geometrical tolerances of components and their assembly using graphical approach. In the work presented in this paper, angularity tolerance has been considered for illustration of the methodology. Two approaches viz. Worst Case (WC) and Root Sum Square (RSS) have been used. An example of dovetail mounting mechanism has been taken for purpose of stack up of angularity. This assembly consists of two parts i.e. dovetail male and dovetail female. Tolerance stack up has been done both for the components and their assembly. Need for computerisation of methodology for geometrical tolerance stack up of large assemblies has emerged out as the limitation of the proposed method.

To implement for large inventory systems becomes rather cumbersome because each item requires managements of order cycle and quantity. The inventory control problem is greatly simplified as only a few groups rather than many items will have to be controlled. This method is the ABC analysis. A.K. Chakaravarty have showed that the optimal groups possess the property of consecutiveness that they are composed of items ordered by the product of their demand rate and holding cost rate (PDHC). The grouping scheme can thus be viewed as a simple process of dividing the items into optimal ranges of the PDHC values. Further the order cycle grouping is shown to be, usually, superior to the order quantity grouping scheme. This paper discusses the analytic properties of the problem of grouping that is modelled as a dynamic programming. Further the graphical method of the order cycle grouping is shown with the numerical method. Also, the economical consideration of almost optimal groups which is based on the principle of dividing the items into convinient ranges of their usage cost rates, is given and we have compared our method with ABC analysis.