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The article presents a study which proposed an optimization approach based on the concept of integrative design with ceramics. According to the study, the major goal of the concept of integrative design with ceramics is the development of an iterative optimization strategy and the effective implementation of finite element method-based results and empiric knowledge for computer-aided design of functional units with ceramic components. The characteristics of the integrative design philosophy are also summarized.

In recent years, artificial neural networks have been used successfully to model multivariate water resources time series. By using analytical approaches to determine appropriate model inputs, network size and training time can be reduced. In this paper, it is proposed that the method of Haugh and Box and a new neural network-based approach can be used to identify the inputs for multivariate artificial neural network models. Both methods were used to obtain the inputs for a multivariate artificial neural network model used for forecasting salinity in the River Murray at Murray Bridge, South Australia. The methods were compared with a third method that uses knowledge of travel times in the river to identify a reasonable set of inputs. The results obtained indicate that all three methods are suitable for determining the inputs for multivariate time series models. However, the neural network-based method is preferable because it is quicker and simpler to use. Any prior knowledge of the underlying processes should be used in conjunction with the neural network method. [ABSTRACT FROM AUTHOR]

Assessing water supply security for urban water supply system (UWSS) planning is now more challenging with the inclusion of non-traditional sources, which increases simulation complexity, and the need to account for climate change impacts, which increases uncertainty. This paper addresses this by developing an integrated framework for assessing the security of UWSSs with non-traditional sources under climate change. The framework is applied to a case study based on the southern Adelaide UWSS. The case study objectives include minimizing cost and maximizing supply security, with the latter assessed using reliability, maximum failure duration, maximum vulnerability, and robustness. Robustness represents the performance of the UWSS across plausible future scenarios, comprising of realizations of climate change and consumer demand. Trade-offs exist between cost and supply security for solutions that use desalination and harvested stormwater to augment water supply; however, use of rainwater tanks is undesirable, as they are an expensive source. [ABSTRACT FROM AUTHOR]

Data splitting is an important consideration during artificial neural network (ANN) development where hold-out cross-validation is commonly employed to ensure generalization. Even for a moderate sample size, the sampling methodology used for data splitting can have a significant effect on the quality of the subsets used for training, testing and validating an ANN. Poor data splitting can result in inaccurate and highly variable model performance; however, the choice of sampling methodology is rarely given due consideration by ANN modellers. Increased confidence in the sampling is of paramount importance, since the hold-out sampling is generally performed only once during ANN development. This paper considers the variability in the quality of subsets that are obtained using different data splitting approaches. A novel approach to stratified sampling, based on Neyman sampling of the self-organizing map (SOM), is developed, with several guidelines identified for setting the SOM size and sample allocation in order to minimize the bias and variance in the datasets. Using an example ANN function approximation task, the SOM-based approach is evaluated in comparison to random sampling, DUPLEX, systematic stratified sampling, and trial-and-error sampling to minimize the statistical differences between data sets. Of these approaches, DUPLEX is found to provide benchmark performance with good model performance, with no variability. The results show that the SOM-based approach also reliably generates high-quality samples and can therefore be used with greater confidence than other approaches, especially in the case of non-uniform datasets, with the benefit of scalability to perform data splitting on large datasets., (Copyright 2009 Elsevier Ltd. All rights reserved.)

We introduce a generic, simple, and inexpensive method for performing microbiological, enzymatic, or inorganic catalysis with solids using standard histology and microbiology laboratory equipment. Histology cassettes were used to standardize hydrodynamic conditions and to protect the catalysts and their solid supports. Histology cassettes have the following advantages: they are readily available, inexpensive, solvent and acid resistant, automatable, and the slots in the cassette walls allow liquid to circulate freely. Standard Erlenmeyer flasks were used as reaction vessels. We developed a new camera to observe the movement and position of the histology cassettes as well as the liquid in the Erlenmeyer flasks. The camera produces a stable image of the rotating liquid in the Erlenmeyer flask. This visualization method revealed that in a 250 ml Erlenmeyer flask, stable operating conditions are achieved at a shaking frequency of 300 rpm and a fill volume of 30 ml. In vessels with vertical walls, such as beakers or laboratory bottles, the movement of the histology cassette is not reproducible. Mass transfer characterization using a biological model system and the chemical sulfite-oxidation method revealed that the histology cassette does not influence gas-liquid mass transfer.

The choice among alternative water supply sources is generally based on the fundamental objective of maximising the ratio of benefits to costs. There is, however, a need to consider sustainability, the environment and social implications in regional water resources planning, in addition to economics. In order to achieve this, multi-criteria decision analysis (MCDA) techniques can be used. Various sources of uncertainty exist in the application of MCDA methods, including the selection of the MCDA method, elicitation of criteria weights and assignment of criteria performance values. The focus of this paper is on the uncertainty in the criteria weights. Sensitivity analysis can be used to analyse the effects of uncertainties associated with the criteria weights. Two existing sensitivity methods are described in this paper and a new distance-based approach is proposed which overcomes limitations of these methods. The benefits of the proposed approach are the concurrent alteration of the criteria weights, the applicability of the method to a range of MCDA techniques and the identification of the most critical criteria weights. The existing and proposed methods are applied to three case studies and the results indicate that simultaneous consideration of the uncertainty in the criteria weights should be an integral part of the decision making process.

Background: With regard to its favorable physical properties, silicon nitride ceramic is considered as biomaterial for human medical application. Minor controversy exists about the biocompatibility of the material., Methods: Cytotoxicity testing, cell viability and morphology assessment was performed applying the L929-mice fibroblast cell culture model in a direct contact assay. Testing materials were silicon nitride ceramics of different surface properties and titanium alloy as a reference. Polyvinylchloride served as a negative control. The cells were stained with bisbenzimide and propidium iodine for double fluorochromasia viability testing, and evaluated by inversion-fluorescence microscopy. Scanning electron microscopy was applied to additionally investigate cell morphology., Results: No cytotoxic effects were observed on the silicon nitride ceramic samples; moreover cell morphology remained the same as on titanium. Avital cells were present exclusively on PVC. The cell growth in the silicon nitride samples showed no significant differences compared to titanium. Cell counts on all polished surfaces showed significantly higher numbers. Scanning electron microscopy revealed typical fibroblast morphology with filiform extensions., Conclusion: The current results indicate a favorable biocompatibility of silicon nitride ceramic. Cell growth, viability and morphology are comparable to parameters of titanium. Polished surfaces appear to promote cell growth. Further in vivo studies are mandatory prior to human medical application. Owing to its favorable physiochemical properties, especially its superior resistance to mechanical stress, silicon nitride could serve as a biomaterial for osteosynthesis of bone with mucosal attachment.

Objectives: The aim of this study was to develop an adequate process-, proof- and calculation technique for the chemical strengthening of dental ceramic materials in order to evaluate the efficiency of this method from the engineering point of view., Methods: Ion exchange examinations below glass temperature have been done for the dental all ceramic system IPS-Empress (Ivoclar). In addition experiments on specimens were undertaken, which were stored in artificial saliva for the period of one month after the ion exchange treatment. The efficiency of the ion-exchange treatments has been evaluated based on the chemical composition of the surface layer, the residual stress distribution, the flexural- and the burst-strength and surface hardness. In addition, Weibull statistical analysis of the four-point bending and burst test data provides new information about the failure mechanisms of chemically strengthened dental ceramics., Results: The ion-exchange process with a potassium salt increases the reliability of the dental ceramic material "IPS-Empress". By the KNO3 or Tuf-Coat ion exchange treatment potassium ions will be implanted as clusters directly into the crystal lattice which results in an increase of the binding energy and hence, in a pronounced increase in the surface hardness. In particular the stress bearing capabilities of dental all ceramic restorations, which are subject to high bending stresses, i.e. dental crowns and dental bridges, are largely improved by the induced residual stresses. This increase of residual stresses did not relax significantly after a one month storage in artificial saliva., Significance: Enhanced load limits and a more narrow strength distribution spectrum is considered desirable for increasing the clinical longevity of all ceramics.