Coil enhancements for high efficiency wireless power transfer applications

Achieving high efficiency with improved power transfer range and misalignment tolerance is the major design challenge in realizing Wireless Power Transfer (WPT) systems for industrial applications. Resonant coils must be carefully designed to achieve highest possible system performance by fully utilizing the available space. High quality factor and enhanced electromagnetic coupling are key indices which determine the system performance. In this paper, design parameter extraction and quality factor optimization of multi layered helical coils are presented using finite element analysis (FEA) simulations. In addition, a novel Toroidal Shaped Spiral (TSS) coil is proposed to increase power transfer range and misalignment tolerance. The proposed shapes and recommendations can be used to design high efficiency WPT resonator in a limited space.

A Crank--Nicolson ADI spectral method for a two-dimensional riesz space fractional nonlinear reaction-diffusion equation

In this paper, a new alternating direction implicit Galerkin--Legendre spectral method for the two-dimensional Riesz space fractional nonlinear reaction-diffusion equation is developed. The temporal component is discretized by the Crank--Nicolson method. The detailed implementation of the method is presented. The stability and convergence analysis is strictly proven, which shows that the derived method is stable and convergent of order $2$ in time. An optimal error estimate in space is also obtained by introducing a new orthogonal projector. The present method is extended to solve the fractional FitzHugh--Nagumo model. Numerical results are provided to verify the theoretical analysis.

Efficiency of parallelisation of genetic algorithms in the data analysis context

Most real-life data analysis problems are difficult to solve using exact methods, due to the size of the datasets and the nature of the underlying mechanisms of the system under investigation. As datasets grow even larger, finding the balance between the quality of the approximation and the computing time of the heuristic becomes non-trivial. One solution is to consider parallel methods, and to use the increased computational power to perform a deeper exploration of the solution space in a similar time. It is, however, difficult to estimate a priori whether parallelisation will provide the expected improvement. In this paper we consider a well-known method, genetic algorithms, and evaluate on two distinct problem types the behaviour of the classic and parallel implementations.

Text mining for screening efficiency? Testing within a Cochrane public health review

Background The requirement for dual screening of titles and abstracts to select papers to examine in full text can create a huge workload, not least when the topic is complex and a broad search strategy is required, resulting in a large number of results. An automated system to reduce this burden, while still assuring high accuracy, has the potential to provide huge efficiency savings within the review process. Objectives To undertake a direct comparison of manual screening with a semi‐automated process (priority screening) using a machine classifier. The research is being carried out as part of the current update of a population‐level public health review. Methods Authors have hand selected studies for the review update, in duplicate, using the standard Cochrane Handbook methodology. A retrospective analysis, simulating a quasi‐‘active learning’ process (whereby a classifier is repeatedly trained based on ‘manually’ labelled data) will be completed, using different starting parameters. Tests will be carried out to see how far different training sets, and the size of the training set, affect the classification performance; i.e. what percentage of papers would need to be manually screened to locate 100% of those papers included as a result of the traditional manual method. Results From a search retrieval set of 9555 papers, authors excluded 9494 papers at title/abstract and 52 at full text, leaving 9 papers for inclusion in the review update. The ability of the machine classifier to reduce the percentage of papers that need to be manually screened to identify all the included studies, under different training conditions, will be reported. Conclusions The findings of this study will be presented along with an estimate of any efficiency gains for the author team if the screening process can be semi‐automated using text mining methodology, along with a discussion of the implications for text mining in screening papers within complex health reviews.

Country review on the main building energy-efficiency policy instrument

Building energy-efficiency (BEE) is the key to drive the promotion of energy saving in building sector. A large variety of building energy-efficiency policy instrument exist. Some are mandatory, some are soft scheme, and some use economic incentives from country to country. This paper presents the current development of implementing BEE policy instruments by examining the practices of BEE in seven selected countries and regions. In the study, BEE policy instruments are classified into three groups, including mandatory administration control instruments, economic incentive instruments and voluntary scheme instruments. The study shows that different countries have adopted different instruments in their practices for achieving the target of energy-saving and gained various kinds of experiences. It is important to share these experiences gained.

The good, the bad, and the efficient: Productivity, efficiency, and technical change in the airline industry, 2004–11

This study models the joint production of desirable and undesirable output production (that is, CO2 emissions) of airlines. The Malmquist–Luenberger productivity index is employed to measure productivity growth when undesirable output production is incorporated into the production model. The results show that pollution abatement activities of airlines lowers productivity growth, which suggests that the traditional approach of measuring productivity growth, which ignores CO2 emissions, overstates ‘true’ productivity growth. The reliability of the results is also tested and verified using confidence intervals based on bootstrapping.

Efficiency or technology adoption: A case study in waste-treatment technology

Improvements in the effectiveness and efficiency of supply-side waste management are necessary in many countries. In Japan, municipalities with limited budgets have delayed the introduction of new waste-management technologies. Thus, the central government has used subsidies to encourage municipalities to adopt certain new technologies to improve waste-management efficiency. In this study, we measure the efficiency of waste management and explore how technology is related to technical efficiency. We find that municipalities are likely to adopt less-efficient technologies and that the central government's policies are likely to promote inefficient technology adoption by local governments.

Indian bank efficiency and productivity changes with undesirable outputs: A disaggregated approach

The objective of this study is to examine technical efficiency and productivity growth in the Indian banking sector over the period from 2004 to 2011. We apply an innovative methodological approach introduced by Chen et al. (2011) and Barros et al. (2012), who use a weighted Russell directional distance model to measure technical inefficiency. We further modify and extend that model to measure TFP change with NPLs. We find that the inefficiency levels are significantly different among the three ownership structure of banks in India. Foreign banks have strong market position in India and they pull the production frontier in a more efficient direction. SPBs and domestic private banks show considerably higher inefficiency. We conclude that the restructuring policy applied in the late 1990s and early 2000s by the Indian government has not had a long-lasting effect.

Re-engineering higher education for energy efficiency solutions

Emerging 21st century challenges require higher education institutions (HEIs) to play a key role in developing graduates and professionals, particularly in engineering and design, who can forge sustainable solutions. The trouble is there’s currently a significant lag in the preparedness of HEIs to provide the stream of professionals needed. Addressing energy efficiency competencies is one critical area.

Stochastic analysis of a radial-inflow turbine in the presence of parametric uncertainties

This paper presents an uncertainty quantification study of the performance analysis of the high pressure ratio single stage radial-inflow turbine used in the Sundstrand Power Systems T-100 Multi-purpose Small Power Unit. A deterministic 3D volume-averaged Computational Fluid Dynamics (CFD) solver is coupled with a non-statistical generalized Polynomial Chaos (gPC) representation based on a pseudo-spectral projection method. One of the advantages of this approach is that it does not require any modification of the CFD code for the propagation of random disturbances in the aerodynamic and geometric fields. The stochastic results highlight the importance of the blade thickness and trailing edge tip radius on the total-to-static efficiency of the turbine compared to the angular velocity and trailing edge tip length. From a theoretical point of view, the use of the gPC representation on an arbitrary grid also allows the investigation of the sensitivity of the blade thickness profiles on the turbine efficiency. The gPC approach is also applied to coupled random parameters. The results show that the most influential coupled random variables are trailing edge tip radius coupled with the angular velocity.

Brain network efficiency and topology depend on the fiber tracking method: 11 tractography algorithms compared in 536 subjects

As connectivity analyses become more popular, claims are often made about how the brain's anatomical networks depend on age, sex, or disease. It is unclear how results depend on tractography methods used to compute fiber networks. We applied 11 tractography methods to high angular resolution diffusion images of the brain (4-Tesla 105-gradient HARDI) from 536 healthy young adults. We parcellated 70 cortical regions, yielding 70×70 connectivity matrices, encoding fiber density. We computed popular graph theory metrics, including network efficiency, and characteristic path lengths. Both metrics were robust to the number of spherical harmonics used to model diffusion (4th-8th order). Age effects were detected only for networks computed with the probabilistic Hough transform method, which excludes smaller fibers. Sex and total brain volume affected networks measured with deterministic, tensor-based fiber tracking but not with the Hough method. Each tractography method includes different fibers, which affects inferences made about the reconstructed networks.

Magnetic nanoparticles boosting the osmotic efficiency of a polymeric FO draw agent: Effect of polymer conformation

Poly sodium acrylate (PSA)-coated Magnetic Nanoparticles (PSA-MNPs) were synthesized as smart osmotic draw agent (SMDA) for water desalination by forward osmosis (FO) process. The PSA-coated MNPs demonstrated significantly higher osmotic pressure (~ 30 fold) as well as high FO water flux (~ 2–3 fold) when compared to their polymer (polyelectrolyte) counterpart, even at a very low concentration of ~ 0.13 wt.% in the draw solution. The PSA polymer chain conformation – coiled to extended – demonstrates a significant impact on the availability of the polymer hydrophilic groups in solution which is the driving force to attain higher osmotic pressure and water flux. When an optimum concentration of the polymer was anchored to a NP surface, the polymer chains assume an extended open conformation making the functional hydrophilic groups available to attract water molecules. This in turn boosts the osmotic pressure and FO water flux of the PSA-MNP draw agents. The low concentration of the PSA-MNP osmotic agent and the associated high water flux enhances the cost-effectiveness of our proposed SMDA system. In addition, easier magnetic separation and regeneration of the SMDA also improves its usability making it efficient, cost-effective and environment-friendly.

Innovation in energy efficiency education for engineers

Energy efficiency as a concept has gained significant attention over the last few decades, as governments and industries around the world have grappled with issues such as rapid population growth and expanding needs for energy, the cost of supplying infrastructure for growing spikes in peak demand, the finite nature of fossil based energy reserves, and managing transition timeframes for expanding renewable energy supplies. Over the last decade in particular, there has been significant growth in understanding the complexity and interconnectedness of these issues, and the centrality of energy efficiency to the engineering profession. Furthermore, there has been a realisation amongst various government departments and education providers that associated knowledge and skill sets to achieve energy efficiency goals are not being sufficiently developed in vocational or higher education. Within this context, this poster discusses the emergence of a national energy efficiency education agenda in Australia, to support embedding such knowledge throughout the engineering curriculum, and throughout career pathways. In particular, the posterprovides insights into the national priorities for capacity building in Australia, and how this is influencing the engineering education community, from undergraduate education through to postgraduate studies and professional development. The poster is intended to assist in raising awareness about the central role of energy efficiency within engineering, significant initiatives by major government, professional, and training organisations, and the increasing availability of high quality energy efficiency engineering education resources. The authors acknowledge the support for and contributions to this poster by the federal Department of Resources, Energy and Tourism, through members of the national Energy Efficiency Advisory Group for engineering education.

Consultation: Energy efficiency and engineering education

This report provides the Commonwealth Department of Resources, Energy and Tourism (RET) with a summary of consultation undertaken with representatives from industry and academia around Australia regarding mainstreaming energy efficiency within engineering education. Specifically, the report documents the purpose of the consultation process, key messages and emerging themes, industry-perceived gaps in energy efficiency related knowledge and skills, and academic considerations regarding graduate attributes and learning pathways to close these gaps. This information complements previous reports by presenting the current thoughts and ideas of more than 100 engineering academic and practising professionals who are actively involved in building capacity through the education system or implementing energy efficiency improvements in companies/the workplace. Furthermore, the report describes the emergence of a potential ‘community of practice’ in energy efficiency capacity building that arose during the project.

State of Education for Energy Efficiency in Australian Engineering Education - Summary of Questionnaire Results

In 2007 the National Framework for Energy Efficiency provided funding for the first survey of energy efficiency education across all Australian universities teaching engineering education. The survey asked the question, ‘What is the state of education for energy efficiency in Australian engineering education?’. There was an excellent response to the survey, with 48 course responses from lecturers across 27 universities from every state and territory in Australia, and 260 student responses from 18 courses across 8 universities from all 6 states. It is concluded from the survey findings that the state of education for energy efficiency in Australian engineering education is currently highly variable and ad hoc across universities and engineering disciplines.