Beliefs and behaviours relevant to the road safety effects of profile lane-marking

Audio-tactile lane-marking (ATLM) is designed to alert inattentive drivers when they deviate from their lane, and appears to reduce crashes. Research into cognitive-behavioural mechanisms underlying, or possibly undermining, the efficacy of ATLM, is limited. We surveyed 775 randomly selected drivers (42% female, up to 75+ years) regarding the profile line-marking (PLM) employed in Australia (and in some European countries). Respondents perceived advantages of PLM in terms of lane-keeping and visibility. Respondents reported avoiding edge-line PLM, so that it may result in driving too close to untreated centre-line. Findings generally allayed concerns, on the basis of risk homeostasis theory, that PLM may increase risky driving. Perceived efficacy of PLM was not associated with increased drink-driving or speeding, but was associated with increased driving while fatigued. Findings suggest that the efficacy of PLM may be increased by employing PLM on both edge- and centre-lines, by exaggerating the audio-tactile effects of PLM that cause drivers to avoid it, and by discouraging the belief that it is safe to drive while fatigued when PLM is present.     

An implicit non-self-report measure of attitudes to speeding: development and validation

Speeding is a major contributor to road trauma and attitudes toward speeding are hypothesised to be a key determinant of the behaviour. Attitudinal research is limited by reliance on self-report measures and the attendant possibility of reporting biases. The Implicit Association Test (IAT) aims to measure attitudes without reliance on self-report, by assessing the association between a target-concept and an evaluation, in terms of reaction time for compatible versus non-compatible pairings. The present research aimed to develop and evaluate an IAT to measure attitudes to speeding. Forty-five licensed drivers completed the speed-related IAT, and drove a driving simulator. Participants also completed a questionnaire that assessed self-reported attitudes to speeding, and several variables theoretically related to attitudes, including speeding behaviour. Observed IAT results suggested that attitudes toward speeding are negative, and were generally consistent with results derived from the simulated driving and self-reported behaviours, beliefs, and attitudes. Thus, the speed-related IAT appears to be a valid measure of attitudes toward speeding, which might be used to measure attitudes in road safety research without reliance on self-report.     

Constrained Message Length Coding for Low Peak to Average Power Ratio in FBMC: OQAM Systems

The FBMC generation techniques are found to surmount the disadvantages of the IFFT/FFT based OFDM system. The minimization of PAPR is a much sought after solution by all multi-carrier methods. This paper investigates the possibility of a unified approach for error control coding and PAPR minimization in an FBMC-OQAM system. A new coding procedure called Constrained Message Length (CML) coding is presented in this paper. A new perspective on PAPR and an analytical framework for estimating the PAPR is also presented. Hybrid techniques using coding and companding are tested for different channel models, and their BER performance is on par with the BCH system. The proposed system is of low complexity and has a PAPR of only 3.81 dB, which is better than or comparable with the existing systems that are using complex methods. This paper has uniquely investigated the dependence of PAPR on the input data variation for a different set of random data loads. The CML coding proposed here can minimize the input data dependent PAPR deviation to a low variance of 0.045 dB, which provides an increased linear region of operation to the power amplifier in the RF section.

     

Comparative spatial metal concentrations and partitioning in bottom sediments of two tropical freshwater lake basins,Kenya

Metal concentrations in the water, sediments and biota in alkaline, near neutral water tropical freshwater lake basins were determined and a comparative analysis made on the spatial and accumulated trace metal concentrations, and geochemical partitioning of iron (Fe), manganese (Mn), copper (Cu), chromium (Cr), zinc (Zn), nickel (Ni), cadmium (Cd) and lead (Pb) in bottom lake sediments. Variable accumulated levels were found in the analysed sediments and aquatic biological tissues. Metal partitioning data in the present study from the two areas exhibits similar trends in magnitude. The residual fractions retained relatively higher amounts of metals. Relatively higher contents of Pb, Cr and Cu were found in Lake Victoria sediments. Cd, Ni, Mn and Pb are of concern because a higher percentage of these metals were retained in the more bioavailable fractions in Lake Naivasha. Total levels of sediment mercury were comparable for the two lake basins. Metals were found in significant levels in the tissues of aquatic organisms, highlighting the potential risks to other levels within the aquatic food chain. Although the exposure risk was not evaluated, it is important to continue monitoring these elements in fish, as sediments were found to contain considerable quantities of the metals. Numerous sediment extraction techniques data applied for evaluating metal partitioning in sediments cannot be compared because of the use of different methods. Nevertheless, the information is still useful in differentiating and understanding pollution loads from natural versus anthropogenic sources and their associated risks.     

Managing resources through stakeholder networks: collaborative water governance for Lake Naivasha basin,Kenya

Stakeholder analysis and social network analysis were used to analyze stakeholders’ social and structural characteristics based on their interests, influence and interactions in Lake Naivasha basin, Kenya. Even though the Kenyan government and its agencies seem to command higher influence and interest in water resource management, the presence of influential and central stakeholders from non-government sectors plays a key role in strengthening partnership in a governance environment with multiple sectors, complex issues and competing interests. Interactions in the basin are guided by stakeholders’ interest and sphere of influence, which have both promoted participation in implementing a collaborative water governance framework.     

Sensors and smart electronics in harsh environment applications

 The limits of sensors in harsh environments are discussed. Failures of sensor materials, interconnects, and cables are shown. Remote measurements can be solutions to overcome material problems. Sensor material and measurement systems are presented for cases such as high temperature, high pressure, toxicity, explosiveness, nuclear radiation, and high electromagnetic pulse (EMP) levels. Received: 4 July 2000/Accepted: 4 July 2000     

Tailoring the textural properties of activated carbon xerogels by chemical activation with KOH

Resorcinol–formaldehyde xerogels synthesised with different resorcinol/sodium carbonate molar ratios were chemically activated either after drying or after drying and pyrolysis, using potassium hydroxide. It was found that organic (i.e. dried) and carbon (i.e. pyrolysed) xerogels behave differently when subjected to chemical activation. In the case of carbon xerogels, the increase in the microporosity takes place without any significant modification to the meso/macroporosity formed during the synthesis step, leading to micro–mesoporous or micro–macroporous materials with a larger micropore volume. Furthermore, control of the microporosity is possible because its development depends on the amount of KOH used. However, when organic xerogels are activated, mainly microporous materials with BET specific surface areas of up to 2000 m² g⁻¹ are obtained, there hardly remaining any of the meso/macroporosity formed during the gel synthesis. Thus, the combination of different synthesis conditions and chemical activation with potassium hydroxide allows the textural properties of carbon xerogels to be tailored at both micropore and meso/macropore levels.     

Segmentation of scanning electron microscopy images from natural rubber samples with gold nanoparticles using starlet wavelets

Electronic microscopy has been used for morphology evaluation of different materials structures. However, microscopy results may be affected by several factors. Image processing methods can be used to correct and improve the quality of these results. In this article, we propose an algorithm based on starlets to perform the segmentation of scanning electron microscopy images. An application is presented in order to locate gold nanoparticles in natural rubber membranes. In this application, our method showed accuracy greater than 85% for all test images. Results given by this method will be used in future studies, to computationally estimate the density distribution of gold nanoparticles in natural rubber samples and to predict reduction kinetics of gold nanoparticles at different time periods. Microsc. Res. Tech. 77:71–78, 2014. © 2013 Wiley Periodicals, Inc.