Detection of sinkhole attack in wireless sensor networks

Generally wireless sensor networks rely of many-to-one communication approach for data gathering. This approach is extremely susceptible to sinkhole attack, where an intruder attracts surrounding nodes with unfaithful routing information, and subsequently presents selective forwarding or change the data that carry through it. A sinkhole attack causes an important threat to sensor networks and it should be considered that the sensor nodes are mostly spread out in open areas and of weak computation and battery power. In order to detect the intruder in a sinkhole attack this paper suggests an algorithm which firstly finds a group of suspected nodes by analyzing the consistency of data. Then, the intruder is recognized efficiently in the group by checking the network flow information. The proposed algorithm's performance has been evaluated by using numerical analysis and simulations. Therefore, accuracy and efficiency of algorithm would be verified.

Pedestrian dynamics in real and simulated world

The paper examines the knowledge of pedestrian movements, both in real scenarios, and from more recent years, in the virtual 4 simulation realm. Aiming to verify whether it is possible to learn from the study of virtual environments how people will behave in real 5 environments, it is vital to understand what is already known about behavior in real environments. Besides the walking interaction among 6 pedestrians, the interaction between pedestrians and the built environment in which they are walking also have greatest relevance. Force-based 7 models were compared with the other three major microscopic models of pedestrian simulation to demonstrate a more realistic and capable 8 heuristic approach is needed for the study of the dynamics of pedestrians.

3D CFD simulations of a candidate R143a radial-inflow turbine for geothermal power applications

Optimisation of Organic Rankine Cycles (ORCs) for binary cycle applications could play a major role in determining the competitiveness of low to moderate renewable sources. An important aspect of the optimisation is to maximise the turbine output power for a given resource. This requires careful attention to the turbine design notably through numerical simulations. Challenges in the numerical modelling of radial-inflow turbines using high-density working fluids still need to be addressed in order to improve the turbine design and better optimise ORCs. This paper presents preliminary 3D numerical simulations of a radial-inflow turbine working with high-density fluids in realistic geothermal ORCs. Following extensive investigation of the operating conditions and thermodynamic cycle analysis, the refrigerant R143a is chosen as the high-density working fluid. The 1D design of the candidate radial-inflow turbine is presented in details. Furthermore, commercially-available software Ansys-CFX is used to perform the 3D CFD simulations for a number of operating conditions including off-design conditions. The real-gas properties are obtained using the Peng-Robinson equations of state. The preliminary design created using dedicated radial-inflow turbine software Concepts-Rital is discussed and the 3D CFD results are presented and compared against the meanline analysis.

A loop cancellation based active damping solution for constant power instability in vehicular power systems

In recent years, electric propulsion systems have increasingly been used in land, sea and air vehicles. The vehicular power systems are usually loaded with tightly regulated power electronic converters which tend to draw constant power. Since the constant power loads (CPLs) impose negative incremental resistance characteristics on the feeder system, they pose a potential threat to the stability of vehicular power systems. This effect becomes more significant in the presence of distribution lines between source and load in large vehicular power systems such as electric ships and more electric aircrafts. System transients such as sudden drop of converter side loads or increase of constant power requirement can cause complete system instability. Most of the existing research work focuses on the modeling and stabilization of DC vehicular power systems with CPLs. Only a few solutions are proposed to stabilize AC vehicular power systems with non-negligible distribution lines and CPLs. Therefore, this paper proposes a novel loop cancellation technique to eliminate constant power instability in AC vehicular power systems with a theoretically unbounded system stability region. Analysis is carried out on system stability with the proposed method and simulation results are presented to validate its effectiveness.

Security and the War on Terror

The terrorist attacks of 11 September 2001 marked a turning point in international politics, representing a new type of threat that could not easily be anticipated or prevented through state-based structures of security alone. Opening up interdisciplinary conversations between strategic, economic, ethical and legal approaches to global terrorism, this edited book recognises a fundamental issue: while major crises initially tend to reinforce old thinking and behavioural patterns, they also allow societies to challenge and overcome entrenched habits, thereby creating the foundations for a new and perhaps more peaceful future. This volume addresses the issues that are at stake in this dual process of political closure, and therefore rethinks how states can respond to terrorist threats. The contributors range from leading conceptual theorists to policy-oriented analysts, from senior academics to junior researchers. The book explores how terrorism has had a profound impact on how security is being understood and implemented, and uses a range of hitherto neglected sources of insight, such as those between political, economic, legal and ethical factors, to examine the nature and meaning of security in a rapidly changing world.

Three dimensional digitisation of plant leaves

Realistic plant models are important for leaf area and plant volume estimation, reconstruction of growth canopies, structure generation of the plant, reconstruction of leaf surfaces and agrichemical spray droplet modelling. This article investigates several different scanning devices for obtaining a three dimensional digitisation of plant leaves with a point cloud resolution of 200-500μm. The devices tested were a Roland mdx-20, Microsoft Kinect, Roland lpx-250, Picoscan and Artec S. The applicability of each of these devices for scanning plant leaves is discussed. The most suitable tested digitisation device for scanning plant leaves is the Artec S scanner.

Mathematical Models of Tumor-Immune System Dynamics

"This collection of papers offers a broad synopsis of state-of-the-art mathematical methods used in modeling the interaction between tumors and the immune system. These papers were presented at the four-day workshop on Mathematical Models of Tumor-Immune System Dynamics held in Sydney, Australia from January 7th to January 10th, 2013. The workshop brought together applied mathematicians, biologists, and clinicians actively working in the field of cancer immunology to share their current research and to increase awareness of the innovative mathematical tools that are applicable to the growing field of cancer immunology. Recent progress in cancer immunology and advances in immunotherapy suggest that the immune system plays a fundamental role in host defense against tumors and could be utilized to prevent or cure cancer. Although theoretical and experimental studies of tumor-immune system dynamics have a long history, there are still many unanswered questions about the mechanisms that govern the interaction between the immune system and a growing tumor. The multidimensional nature of these complex interactions requires a cross-disciplinary approach to capture more realistic dynamics of the essential biology. The papers presented in this volume explore these issues and the results will be of interest to graduate students and researchers in a variety of fields within mathematical and biological sciences."--Publisher website

Optimisation methods for coupled thermodynamic and 1D design of radial-inflow turbines

Optimisation is a fundamental step in the turbine design process, especially in the development of non-classical designs of radial-inflow turbines working with high-density fluids in low-temperature Organic Rankine Cycles (ORCs). The present work discusses the simultaneous optimisation of the thermodynamic cycle and the one-dimensional design of radial-inflow turbines. In particular, the work describes the integration between a 1D meanline preliminary design code adapted to real gases and the performance estimation approach for radial-inflow turbines in an established ORC cycle analysis procedure. The optimisation approach is split in two distinct loops; the inner operates on the 1D design based on the parameters received from the outer loop, which optimises the thermodynamic cycle. The method uses parameters including brine flow rate, temperature and working fluid, shifting assumptions such as head and flow coefficients into the optimisation routine. The discussed design and optimisation method is then validated against published benchmark cases. Finally, using the same conditions, the coupled optimisation procedure is extended to the preliminary design of a radial-inflow turbine with R143a as working fluid in realistic geothermal conditions and compared against results from commercially-available software RITAL from Concepts-NREC.

School based youth health nurses and attrition : the reasons for moving on

Like the UK, Australia has a number of school nursing models and programmes. The School Based Youth Health Nurse Program (SBYHNP) is a new and unique model of school nursing in Queensland, Australia. The SBYHNP represents a philosophical and structural shift from traditional school nursing programmes. The purpose of this qualitative case study is to explore the reasons School Based Youth Health Nurses (SBYHN) leave school nursing. Sixteen in-depth interviews were conducted with participants who practiced as SBYHN and left the SBYHNP. This case study reveals six themes: The politics’: Navigating the organisational divide, 'Unconditional positive regard’: Surviving without team cohesion, 'Absolutely exhausted’: Maintaining physical and emotional strength, ‘Definitely geographical’: Managing the tyranny of time and distance, ‘If things fell into place’: Thinking about what could have been, and ‘A stepping stone’: Moving on to the next nursing position. This case study suggests nurses considering school nursing as a specialty should seek opportunity to understand this complex role, ensure realistic expectations and ndertake relevant qualifications. This approach may secure the investment made by nurses and schools and create demand for a highly sort after position.

Ectopic overexpression of a mungbean vacuolar Na+/H+ antiporter gene (VrNHX1) leads to increased salinity stress tolerance in transgenic Vigna unguiculata L. Walp

Salinity is a major threat to sustainable agriculture worldwide. Plant NHX exchangers play an important role in conferring salt tolerance under salinity stress. In this study, a vacuolar Na+/H+ antiporter gene VrNHX1 (Genbank Accession No. JN656211.1) from mungbean (Vigna radiata) was introduced into cowpea (Vigna unguiculata) by the Agrobacterium tumefaciens-mediated transformation method. Polymerase chain reaction and Southern blot hybridization confirmed the stable integration of VrNHX1 into the cowpea genome. Comparative expression analysis by semi-quantitative RT-PCR revealed higher expression of VrNHX1 in transgenic cowpea plants than wild-type. Under salt stress conditions, T2 transgenic 35S:VrNHX1 cowpea lines exhibited higher tolerance to 200 mM NaCl treatment than wild-type. Furthermore, T2 transgenic 35S:VrNHX1 lines maintained a higher K+/Na+ ratio in the aerial parts under salt stress and accumulated higher [Na+] in roots than wild-type. Physiological analysis revealed lower levels of lipid peroxidation, hydrogen peroxide and oxygen radical production but higher levels of relative water content and proline, ascorbate and chlorophyll contents in T2 transgenic 35S:VrNHX1 lines.

Child observation as teachers' work in contemporary Australian early childhood programs

This article reports data from a study of how teachers use child observations in one State in Australia. It argues that the current economic and political climate has meant changes for most early childhood settings catering for children prior to school entry. How teachers in these various settings deal with changes in relation to child observation depends on the contexts in which they work. The paper suggests that the purpose of observing children is changing and that traditionally accepted ways of writing child observations may be under threat.

Surface reconstruction of wheat leaf morphology from three-dimensional scanned data

Realistic virtual models of leaf surfaces are important for a number of applications in the plant sciences, such as modelling agrichemical spray droplet movement and spreading on the surface. In this context, the virtual surfaces are required to be sufficiently smooth to facilitate the use of the mathematical equations that govern the motion of the droplet. While an effective approach is to apply discrete smoothing D2-spline algorithms to reconstruct the leaf surfaces from three-dimensional scanned data, difficulties arise when dealing with wheat leaves that tend to twist and bend. To overcome this topological difficulty, we develop a parameterisation technique that rotates and translates the original data, allowing the surface to be fitted using the discrete smoothing D2-spline methods in the new parameter space. Our algorithm uses finite element methods to represent the surface as a linear combination of compactly supported shape functions. Numerical results confirm that the parameterisation, along with the use of discrete smoothing D2-spline techniques, produces realistic virtual representations of wheat leaves.

Connecting theory, practice and place in today’s landscape : an education initiative

Since the establishment of Australia’s earliest formal studies in landscape architecture, landscape planning has been a traditional focus within post-graduate studies at QUT. Study in this area has evolved from an earlier emphasis on applied physical geography through to traditional techniques and processes in visual assessment and management. The emphasis on these techniques has shifted again to a more complex exploration of natural, economic, social and cultural landscapes. Recently, the School has explored more innovative and complex dimensions of human and natural landscapes. This has involved a focus on particular regions under pressure from local social and economic change. These have included the under-threat ‘picturesque’ landscapes of the Blackall Range and the Tweed Valley. Attempts to bridge the institution and the landscape have unearthed, through a studio focus, strong connections with notions of sustainable villages, roadside interpretation, way finding, local economic initiatives, special area creation, cultural heritage brokering and ecological enhancements. These initiatives have spanned both local practice interests and academic pursuits. Central to this exploration is the concept of problem solving through the investigation of the concept of ‘multiple scales’. An open, yet intensive program is being developed with a team of ‘futurist’ practitioners offering a range of experiences and perspectives to students. The program is being increasingly linked to design studios so that landscape planning and landscape design form a fabric of inquiry that works towards reclaiming complex landscapes.

Maintaining the ethic of service [Editorial]

This issue of Precedent is concerned with professional legal ethics. ln my view, professional ethics are rules about how you do your job, based on moral principles. By virtue of the nature of the work they do, the reputation of the institution through which they are admitted to practice (the court), and the consequences that can flow if they act inappropriately or incompetently, lawyers are under constant scrutiny in all aspects of their lives. Errors, omissions or misdeeds in both their professional and their personal lives have the potential to damage them, their clients, the profession itself and the court. We ought never to take for granted the trust the public places in us to preserve the integrity of the legal system itself, especially in times when that system may be under threat, either from without or from within.

Assessing uncertainty in pollutant wash-off modelling via model validation

Stormwater pollution is linked to stream ecosystem degradation. In predicting stormwater pollution, various types of modelling techniques are adopted. The accuracy of predictions provided by these models depends on the data quality, appropriate estimation of model parameters, and the validation undertaken. It is well understood that available water quality datasets in urban areas span only relatively short time scales unlike water quantity data, which limits the applicability of the developed models in engineering and ecological assessment of urban waterways. This paper presents the application of leave-one-out (LOO) and Monte Carlo cross validation (MCCV) procedures in a Monte Carlo framework for the validation and estimation of uncertainty associated with pollutant wash-off when models are developed using a limited dataset. It was found that the application of MCCV is likely to result in a more realistic measure of model coefficients than LOO. Most importantly, MCCV and LOO were found to be effective in model validation when dealing with a small sample size which hinders detailed model validation and can undermine the effectiveness of stormwater quality management strategies.