Generalized pseudo-likelihood estimates for markov random fields on lattice

In this paper we generalize Besag's pseudo-likelihood function for spatial statistical models on a region of a lattice. The correspondingly defined maximum generalized pseudo-likelihood estimates (MGPLEs) are natural extensions of Besag's maximum pseudo-likelihood estimate (MPLE). The MGPLEs connect the MPLE and the maximum likelihood estimate. We carry out experimental calculations of the MGPLEs for spatial processes on the lattice. These simulation results clearly show better performances of the MGPLEs than the MPLE, and the performances of differently defined MGPLEs are compared. These are also illustrated by the application to two real data sets.

Deconstructing diversity discourses in the fields of educationnal management and leadership

Discourses of diversity have supplanted those of equal opportunity or social justice in many Western democratic societies. While the notion of diversity is seemingly empowering through its recognition of cultural, religious, racial and gender difference within nation states, the emergence of this discourse during the 1990s has been in the context of neoliberal managerialist discourses that assume social action is fully explicable through theories of maximizing self interest. Thus notions of diversity, while originating in collective demands of social movements of feminism, anti racism and multiculturalism of the 1970s and 1980s, have in recent times privileged learning and leadership as an individual accomplishment and not a collective practice. Thus the dominant discourse of diversity is more in alignment with the deregulatory aspects of the increasingly managerial and market orientation of schooling, decentring earlier discourses of more transformatory notions premised upon reducing inequality and discrimination and developing ‘inclusivity’ in and through schooling. This paper provides a contextual and conceptual framework through which to explore the intersections and divergences of discourses of diversity in schools and their practical application.

The influence of magnetic fields exposure on neurite outgrowth in PC12 rat pheochromocytoma cells

The aim of present work was to investigate the influence of magnetic fields exposure on neurite outgrowth in PC12 cells. The neurite number per cell, length of neurites and directions of neurite growth with respect to the direction of the magnetic field were analyzed after exposure to 50 Hz electromagnetic field for 96 h. A promotion was observed under a weak field (0.23 mT), as the average number of neurites per cell increased to 2.38±0.06 compared to 1.91±0.07 neurites/cell of the control dishes, while inhibition and directional outgrowth was evident under a relatively stronger field (1.32 mT). Our work shows that biological systems can be very sensitive to the strength of electromagnetic field.

Controlling the relative orientation between the two magnetic fields of a synchronous motor

A simple and reliable method for controlling the relative orientation between the two magnetic fields of a permanent magnet synchronous motor is presented. Finding the initial (at motor powering-up time) value of this relative location is essential for the proper operation of the motor. The feedback control loop used finds this initial relative orientation quickly. Further, using the proposed method allows considerable cost saving, as a transducer that is usually used for this purpose can be eliminated. The cost saving is most obvious in the case of linear motors and angle motors with large diameters. The way the problem is posed is an essential part of this work and it is the reason behind the apparent simplicity of the solution. The method relied upon a single sensor, and it has been tested when a relative encoder was used

Developing effective learning programs : what extension can learn from the fields of adult education and learning communities

Learning is an investment in capacity building that has and will continue to reap rewards for primary producers and government in terms of increased sustainable production, profitability, exports, jobs and sustainable rural communities. Primary production operates in a context of continual change and requires up to date, complex and varied skills of primary producers and land managers.

A recent national research project funded by the Department of Agriculture, Forestry and Fisheries Australia confirmed that application of best practice from the theory of adult education in designing and developing learning programs in primary industry results in learning activities that provide information that is relevant to farmers’ needs, delivered in an entertaining way, and that draws on examples directly relevant to the participants. As a result, the training often exceeds the expectations of the participants.

The project produced a self-assessment checklist to identify ways of improving the development and delivery of training for extension practitioners and training providers. The key issues include continuous monitoring of client’s needs, and actively seeking opportunities to meet and work with industry organisations, other training providers and funding bodies.

There appear to be two drivers for the development of learning programs. One is problems or opportunities identified by people and organisations that could be termed ‘scanners’ and who tend not to be potential participants, the other is learning needs expressed by individuals or enterprises who want to participate in learning activities (participants). Scanners are typically industry organisations, government agencies and researchers, but may include providers and participants. Extension practitioners are well-placed to act as scanners.

It is very important that farmers and farmer organisations contribute to the development of new learning programs. Without industry input and support, extension practitioners and training providers cannot be expected to ensure they meet client needs. In other words, to develop effective learning programs, there must an industry learning community of producers, industry organisations, extension practitioners and training providers and other stakeholders such as supply chain enterprises, government and researchers.

Practice chains of production and consumption : mediatized practices across social fields

The argument developed in this paper is that a focus on practice provides some resolutions to methodological problems facing Bourdieuian scholarship in education. In order to develop Bourdieu's work on practice to account for the interactions between practices, this paper presents a conceptualization of practice as chains of production and consumption. The first part of the paper reviews the account of practice offered by Bourdieu both embedded in practice games and as field effects. The second part of the paper introduces practice chains of production and consumption as a way to conceptualize practice by drawing on a case involving print journalists' involvement with policy makers over the course of an Australian policy review. The final section presents a discussion of this conceptualization and highlights the potential of the concept for further research in understanding the processes of educational policy development.

Cross-field effects and temporary social fields : a case study of the mediatization of recent Australian knowledge economy policies

This paper utilizes Bourdieu's conceptual frame to examine the mediatized effects of policy processes concerned with the growth and support of knowledge industries in Australia. These policies span education, science, research and other knowledge industries (such as venture capital firms and intellectual property law). The paper argues that some policy processes are best represented as temporary social fields. The nature of these fields can be described by the kinds of cross-field effects that they produce, A case study of an Australian knowledge economy policy, The chance to change, and associated policy processes demonstrates the broad analytic capacities of Bourdieu 's conceptual frame for policy analysis, when combined with the concepts of cross-field effects and temporary social field developed here.

Effects of electric fields on pollen rupture

RATIONALE: To determine whether the potential for previous termpollennext term fragmentation is increased during thunderstorms by exploring the previous termeffectsnext term of previous termelectricnext termprevious termfieldsnext term, with magnitude as found in the outdoor environment.

METHODS: Fresh previous termpollennext term grains were collected from bermudagrass flowers. A light microscope was modified with the addition of an previous termelectricnext termprevious termfieldnext term generated from a DC source (0-20 V) that was applied to the stage. Water was added to test for previous termpollennext termprevious termrupturenext term and to assess previous termpollennext term viability.

RESULTS: Bermuda grass previous termpollennext term did not previous termrupturenext term within 1 h of contact with water. Only after exposure to an previous termelectricnext termprevious termfieldnext term did Bermudagrass previous termpollennext term show a considerable amount of rupturing immediately upon immersion in water. The higher the voltage the previous termpollennext term is exposed to before coming into contact with water, the higher the percentage of previous termrupturenext term of the previous termpollennext term. previous termElectricnext termprevious termfieldsnext term, generated in the laboratory and of magnitude found during thunderstorms, affected the previous termpollennext term after as little as a 5 s exposure. The highest percentage of previous termrupturenext term occurred after exposures of at least 10 s: 80% previous termrupturenext term occurred after 10 s exposure at 10kVolts/m. This previous termeffectnext term is sustained for at least 15 min.

CONCLUSIONS: Thunderstorm regularly generate previous termelectricnext termprevious termfieldsnext term up to 5 kV/m in strength, and can reach 10kV/m, and cover several km in distance. The magnitude of the previous termelectricnext termprevious termfieldsnext term that affects the previous termpollennext term grains in the laboratory is low enough to be commonly found in the outdoor environment during thunderstorms. These previous termelectricnext termprevious termfields prime previous termpollen grains for more rapid release of allergenic particles.

Key predistribution scheme using finite fields and reed muller codes

Resource constraint sensors of a Wireless Sensor Network (WSN) cannot afford the use of costly encryption techniques like public key while dealing with sensitive data. So symmetric key encryption techniques are preferred where it is essential to have the same cryptographic key between communicating parties. To this end, keys are preloaded into the nodes before deployment and are to be established once they get deployed in the target area. This entire process is called key predistribution. In this paper we propose one such scheme using unique factorization of polynomials over Finite Fields. To the best of our knowledge such an elegant use of Algebra is being done for the first time in WSN literature. The best part of the scheme is large number of node support with very small and uniform key ring per node. However the resiliency is not good. For this reason we use a special technique based on Reed Muller codes proposed recently by Sarkar, Saha and Chowdhury in 2010. The combined scheme has good resiliency with huge node support using very less keys per node.

Hierarchical semi-markov conditional random fields for recursive sequential data

Inspired by the hierarchical hidden Markov models (HHMM), we present the hierarchical semi-Markov conditional random field (HSCRF), a generalisation of embedded undirected Markov chains to model complex hierarchical, nested Markov processes. It is parameterised in a discriminative framework and has polynomial time algorithms for learning and inference. Importantly, we develop efficient algorithms for learning and constrained inference in a partially-supervised setting, which is important issue in practice where labels can only be obtained sparsely. We demonstrate the HSCRF in two applications: (i) recognising human activities of daily living (ADLs) from indoor surveillance cameras, and (ii) noun-phrase chunking. We show that the HSCRF is capable of learning rich hierarchical models with reasonable accuracy in both fully and partially observed data cases.