Product quality-based eco-efficiency applied to digital cameras

When calculating eco-efficiency, there are considerable confusion and controversy about what the product value is and how it should be quantified. We have proposed here a quantification method for eco-efficiency that derives the ratio of the multiplication value of the product quality and the life span of a product to its whole environmental impact based on Life Cycle Assessment (LCA). In this study, product quality was used as the product value and quantified by the following three steps: (1) normalization based on a value function, (2) determination of the subjective weighting factors of the attributes, and (3) calculation of product quality of the chosen products. The applicability of the proposed method to an actual product was evaluated using digital cameras. The results show that the eco-efficiency values of products equipped with rechargeable batteries were higher than those products that use alkaline batteries, because of higher quality values and lower environmental impacts. The sensitivity analysis shows that the proposed method was superior to the existing methods, because it enables to identify the quality level of the chosen products by considering all products that have the same functions in the market and because, when adding a new product, the calculated quality values in the proposed method do not have to be changed.     

Sensor design for saltwater ingress detection in high reliable all-electric deep sea actuators

Subsea oil and gas production relies on Xmas Trees which are mounted on boreholes. Xmas Trees are an arrangement of different valve types and sizes actuated by hydraulic, electro-mechanic or all-electric actuators. All these actuators sharing problems with saltwater ingress and the re-sulting increased wear. This paper investigates potential effects which can be measured after saltwater ingress. Extensive testing is executed and the investigated effects are used for novel sensor designs. These designs are evaluated regarding certain requirements and a resulting sen-sor design is proposed for industrialization. The resulting sensor can then be used to collect new important data to support optimal maintenance in the subsea industry.     

The use of valuation and weighting sets in environmental impact assessment

In environmental impact assessment of policies and product design results need to be presented in a comprehensible way to make alternatives easily comparable. One way of doing this is to aggregate results to a manageable set by using weighting methods. Valuing the environmental impacts can be a challenging task that can also be quite time-consuming. To the aid of practitioners, several weighting sets with readily available weights have been developed over the last decade. The scope and coverage of these sets vary, and it is important to be aware of the implications of using different valuation methods and weighting sets.The aim of this paper is to map valuation and weighting techniques and indicate the methods that are suitable to use, depending on the purpose of the analysis. Furthermore, we give an overview over sets of generic values or weights and their properties, and give an illustration of how different sets may influence the results. It is very useful to use several weighting sets, and discuss the results thoroughly. It is often a very interesting and fruitful exercise to see if and how the results differ, why they differ, and which one seems to be the best alternative to base any recommendation on.The example provided in this article demonstrates that looking at aggregate results is not enough. Since many weighting sets are not sufficiently transparent as to how they are constructed and what their impact categories actually include, a general recommendation is to provide weighting sets with a declaration of content, providing a clear picture of what is included and what is not, and a recommendation of suitable uses of the weighting set.