Blocking layer optimisation of poly(3-hexylthiopene)based solid state dye sensitized solar cells

The optimisation study of the fabrication of a compact TiO2 blocking layer (via Spray Pyrolysis Deposition) for poly (3-hexylthiopene) (P3HT) for Solid State Dye Sensitized Solar Cells (SDSCs) is reported. We used a novel spray TiO2 precursor solution composition obtained by adding acetylacetone to a conventional formulation (Diisopropoxytitanium bis (acetylacetonate) in ethanol). By Scanning Electron Microscopy a TiO2 layer with compact morphology and thickness of around 100 nmis shown. Through a Tafel plot analysis an enhancement of the device diode-like behaviour induced by the acetylacetone blocking layer respect to the conventional one is observed. Significantly, the device fabricatedwith the acetylacetone blocking layer shows an overall increment of the cell performance with respect to the cellwith the conventional one (DJsc/Jsc = +13.8%, DFF/FF = +39.7%, DPCE/PCE = +55.6%). A conversion efficiency optimumis found for 15 successive spray cycles where the diode-like behaviour of the acetylacetone blocking layer is more effective. Over three batches of cells (fabricated with P3HT and dye D35) an average conversion efficiency value of 3.9% (under a class A sun simulator with 1 sun A.M. 1.5 illumination conditions) was measured. From the best cell we fabricated a conversion efficiency value of 4.5% was extracted. This represents a significant increment with respect to previously reported values for P3HT/dye D35 based SDSCs.

Political networks on twitter : tweeting the Queensland state election

This paper examines patterns of political activity and campaigning on Twitter in the context of the 2012 election in the Australian state of Queensland. Social media have been a visible component of political campaigning in Australia at least since the 2007 federal election, with Twitter, in particular, rising to greater prominence in the 2010 federal election. At state level, however, they have remained comparatively less important thus far. In this paper, we track uses of Twitter in the Queensland campaign from its unofficial start in February through to the election day of 24 March 2012. We both examine the overall patterns of activity in the hash tag #qldvotes, and track specific interactions between politicians and other users by following some 80 Twitter accounts of sitting members of parliament and alternative candidates. Such analysis provides new insights into the different approaches to social media campaigning which were embraced by specific candidates and party organisations, as well as an indication of the relative importance of social media activities, at present, for state-level election campaigns.

Final-state effects in neutron Compton scattering measurements on zirconium deuteride and beryllium

We report inelastic neutron scattering measurements of the neutron Compton profile, J(y), for Be and for D in polycrystalline ZrD2 over a range of momentum transfers, q between 27 and 178 °A−1. The measurements were performed using the inverse geometry spectrometer eVS which is situated at the UK pulsed spallation neutron source ISIS. We have investigated deviations from impulse approximation (IA) scattering which are generically referred to as final state effects (FSEs) using a method described by Sears. This method allows both the magnitude and the q dependence of the FSE to be studied. Analysis of the measured data was compared with analysis of numerical simulations based on the harmonic approximation and good agreement was found for both ZrD2 and Be. Finally we have shown how (∇2V), where V is the interatomic potential, can be extracted from the antisymmetric component of J(y).

Effects of free flow state highway traffic parameters on the performance of amplify and forward cooperative multi-hop vehicular networks

In this paper we analyse the effects of highway traffic flow parameters like vehicle arrival rate and density on the performance of Amplify and Forward (AF) cooperative vehicular networks along a multi-lane highway under free flow state. We derive analytical expressions for connectivity performance and verify them with Monte-Carlo simulations. When AF cooperative relaying is employed together with Maximum Ratio Combining (MRC) at the receivers the average route error rate shows 10-20 fold improvement compared to direct communication. A 4-8 fold increase in maximum number of traversable hops can also be observed at different vehicle densities when AF cooperative communication is used to strengthen communication routes. However the theorical upper bound of maximum number of hops promises higher performance gains.

An approach for identifying the limit states of resilience of a water supply system

This paper presents an approach for identifying the limit states of resilience in a water supply system when influenced by different types of pressure (disturbing) forces. Understanding of systemic resilience facilitates identification of the trigger points for early managerial action to avoid further loss of ability to provide satisfactory service availability when the ability to supply water is under pressure. The approach proposed here is to illustrate the usefulness of a surrogate measure of resilience depicted in a three dimensional space encompassing independent pressure factors. That enables visualisation of the transition of the system-state (resilience) between high to low resilience regions and acts as an early warning trigger for decision-making. The necessity of a surrogate measure arises as a means of linking resilience to the identified pressures as resilience cannot be measured directly. The basis for identifying the resilience surrogate and exploring the interconnected relationships within the complete system, is derived from a meta-system model consisting of three nested sub-systems representing the water catchment and reservoir; treatment plant; and the distribution system and end-users. This approach can be used as a framework for assessing levels of resilience in different infrastructure systems by identifying a surrogate measure and its relationship to relevant pressures acting on the system.

How long does it take for aquifer recharge or aquifer discharge processes to reach steady state?

Groundwater flow models are usually characterized as being either transient flow models or steady state flow models. Given that steady state groundwater flow conditions arise as a long time asymptotic limit of a particular transient response, it is natural for us to seek a finite estimate of the amount of time required for a particular transient flow problem to effectively reach steady state. Here, we introduce the concept of mean action time (MAT) to address a fundamental question: How long does it take for a groundwater recharge process or discharge processes to effectively reach steady state? This concept relies on identifying a cumulative distribution function, $F(t;x)$, which varies from $F(0;x)=0$ to $F(t;x) \to \infty$ as $t\to \infty$, thereby providing us with a measurement of the progress of the system towards steady state. The MAT corresponds to the mean of the associated probability density function $f(t;x) = \dfrac{dF}{dt}$, and we demonstrate that this framework provides useful analytical insight by explicitly showing how the MAT depends on the parameters in the model and the geometry of the problem. Additional theoretical results relating to the variance of $f(t;x)$, known as the variance of action time (VAT), are also presented. To test our theoretical predictions we include measurements from a laboratory–scale experiment describing flow through a homogeneous porous medium. The laboratory data confirms that the theoretical MAT predictions are in good agreement with measurements from the physical model.

A bondgraph approach to formation control using relative state measurements

In this paper we apply port-Hamiltonian theory with the bondgraph modelling approach to the problem of formation control using partial measurements of relative positions. We present a control design that drives a group of vehicles to a desired formation without requiring inter-vehicle communications or global position and velocity measurements to be available. Our generic approach is applicable to any form of relative measurement between vehicles, but we specifically consider the important cases of relative bearings and relative distances. In the case of bearings, our theory closely relates to the field of image-based visual servo (IBVS) control. We present simulation results to support the developed theory.

Review : "Ghosts...of the Civil Dead" -- John Hillcoat

Synopsis and review of the Australian prison film Ghosts...of the Civil Dead (John Hillcoat, 1988). Drawing heavily from the book In the Belly of the Beast by American author and long-term prisoner Jack Henry Abbott, as well as from the historical and philosophical work of Michel Foucault (the credits include ‘Foucault Authority – Simon During’), Ghosts… Of the Civil Dead is a searing critique of the so-called ‘new generation’ prison system developed in the United States and recently introduced in Australia. Director John Hillcoat and producer Evan English conducted extensive research for the film, including spending time at the National Institute of Corrections, a think tank in Colorado, and visiting numerous institutions like the ‘new Alcatraz’ at Marion Illinois and other maximum security prisons across the United States. Using a mix of professionals and non-actors, including former prisoners and prison guards, the ‘story’ was workshopped during a lengthy rehearsal period with many actual events and experiences of participants incorporated into the film. The end result deliberately blurs the line between American and Australian prison experience to make the political point that what had happened in the US – from where many events and characters, and much of the architecture and design of the prison are drawn – was beginning to happen in Australia. The film emphasises the vicious cycle of institutionalisation, and highlights the role state authorities play in manufacturing, provoking and manipulating violence and fear both in prisons and in wider society as a means to augment policing and surveillance of the population, to oppress the working classes, and to maintain the political status quo...

Carbon dioxide reforming of methane to produce synthesis gas over metal-supported catalysts: State of the art

Carbon dioxide reforming of methane produces synthesis gas with a low hydrogen to carbon monoxide ratio, which is desirable for many industrial synthesis processes. This reaction also has very important environmental implications since both methane and carbon dioxide contribute to the greenhouse effect. Converting these gases into a valuable feedstock may significantly reduce the atmospheric emissions of CO2 and CH4. In this paper, we present a comprehensive review on the thermodynamics, catalyst selection and activity, reaction mechanism, and kinetics of this important reaction. Recently, research has centered on the development of catalysts and the feasible applications of this reaction in industry. Group VIII metals supported on oxides are found to be effective for this reason. However, carbon deposition causing catalyst deactivation is the major problem inhibiting the industrial application of the CO2/CH4 reaction. Ni-based catalysts impregnated on certain supports show carbon-free operation and thus attract much attention. To develop an effective catalyst for CO2 reforming of CH4 and accelerate the commercial application of the reaction, the following are identified to be the most important areas for future work: (1) selection of metal and support and studying the effect of their interaction on catalyst activity; (2) the effect of different promoter on catalyst activity; (3) the reaction mechanism and kinetics; and (4) pilot reactor performance and scale-up operation.

Teaching end-user remote online searching

The Queensland University of Technology (QUT) Library bas recently commenced teaching higher degree students to search online systems such as BRS, ORBIT and STN. The emphasis is on education rather than training. with students being required to familiarise themselves with system commands and database structures whilst receiving necessarily limited tutorial help. The teaching strategies used and problems encountered in the program are outlined. Student responses to the experience of learning to online search are discussed.

Towards better end-of-life care : a major opportunity for nurses to contribute to the debate

Integrated care pathways are documents which outline the essential steps of multidisciplinary care in addressing a specific clinical problem (Rotter et al., 2010). They can be used to introduce clinical guidelines and systematic audits of clinical practice, and to ensure that the most appropriate management occurs at the most appropriate time and that it is provided by the most appropriate health professional. The Liverpool Care Pathway (LCP) is an example of an integrated care pathway, designed in the 1990s to guide care for people who are in their last days of life (Ellershaw et al., 1997, Ellershaw and Ward, 2003)...

Biomechanical aspects of seating comfort in vehicle seating package engineering

In this paper, problems are described which are related to the ergonomic assessment of vehicle package design in vehicle systems engineering. The traditional approach, using questionnaire techniques for a subjective assessment of comfort related to package design, is compared to a biomechanical approach. An example is given for ingress design. The biomechanical approach is based upon objective postural data. The experimental setup for the study is described and methods used for the biomechanical analysis are explained. Because the biomechanic assessment requires not only a complex experimental setup but also time consuming data processing, a systematic reduction and preparation of biomechanic data for classification with an Artificial Neural Network significantly improves the economy of the biomechanical method.

The Chinese state enterprise sector: Labour market reform and the impact on male–female wage structure

The paper examines the wage structure in the Chinese state enterprise sector between 1981 and 1987. This period is of particular interest given the introduction of major labour market reforms in China during the early 1980s. In essence the reforms represented a movement away from administratively determined prices towards a market–oriented system combined with a relatively flexible system of labour allocation. The Juhn, Murphy and Pierce (1991) decomposition is employed to shed light on the role of changing labour market institutions over the period.