Multi-input-multi-output antennas for radio frequency identification systems

In this chapter the authors discuss the physical insight of the role of wireless communication in RFID systems. In this respect, this chapter gives a brief introduction on the wireless communication model followed by various communication schemes. The chapter also discusses various channel impairments and the statistical modeling of fading channels based on the environment in which the RFID tag and reader may be present. The chapter deals with the fact that the signal attenuations can be dealt with up to some level by using multiple antennas at the reader transmitter and receiver to improve the performance. Thus, this chapter discusses the use of transmit diversity at the reader transmitter to transmit multiple copies of the signal. Following the above, the use of receiver combining techniques are discussed, which shows how the multiple copies of the signal arriving at the reader receiver from the tag are combined to reduce the effects of fading. The chapter then discusses various modulation techniques required to modulate the signal before transmitting over the channel. It then presents a few channel estimation algorithms, according to which, by estimating the channel state information of the channel paths through which transmission takes place, performance of the wireless system can be further increased. Finally, the Antenna selection techniques are presented, which further helps in improving the system performance.

Process drama and digital games as text and action in virtual worlds : developing new literacies in school

This article explores the intersections between drama and digital gaming and the educational possibilities for literacy of both. The article draws on a model for the educational uses of digital gaming and three case studies from the Australian Research Council funded three and a half year project, Literacy in the digital world of the twenty first century: Learning from computer games. This model theorises the scope of the possibilities for literacy outcomes from the usage of computer games. The article describes how the model works, and then applies the model to drama education, specifying some new ways of thinking about the literacy outcomes from drama education. Process drama is theorised as the creation of text-in-action.

Adaptation of LEACH routing protocol to cognitive radio sensor networks

One of the drawbacks of LEACH protocol is the uncontrolled selection of cluster heads which, in some rounds, leads to the concentration of them in a limited area due to the randomness of the selection procedure. LEACH-C is a variant of LEACH that uses a centralized clustering algorithm and forms good clusters through sink control. According to experimental results, the IEEE 802.15.4 packets are damaged by WLAN interferences in ISM band. It seems that, sensor nodes equipped with cognitive radio capabilities can overcome this problem. In cognitive radio sensor networks (CRSN), routing must be accompanied by channel allocation. This requires spectrum management which can be devolved to cluster heads. For this networks, new duty cycle mechanisms must be designed that jointly consider neighbor discovery, and spectrum sensing/allocation. Cluster-based network architecture is a good choice for effective dynamic spectrum management. In such architecture, cluster heads have a proper spatial distribution and are optimally located all over the network. In this paper, using the physical layer information and preserving the feature of random cluster head selection in LEACH, it has been tried to both move the position of cluster heads to appropriate locations and make their quantity optimal. The simulation results show that the transferal of cluster heads to appropriate locations increases the network lifetime significantly though this comes at the price of early instability appearance. By considering the energy level in cluster head election algorithm, one can overcome the network stability issues too. However, this will move the cluster heads away from their appropriate locations. © 2012 IEEE.

Study of radio frequency plasma treatment of PVDF film using Ar, O2 and Ar + O2 gases for improved polypyrrole adhesion

Improvement of the binding of polypyrrole with PVDF (polyvinylidene fluoride) thin film using low pressure plasma was studied. The effects of various plasma gases i.e., Ar, O2 and Ar + O2 gases on surface roughness, surface chemistry and hydrophilicity were noted. The topographical change of the PVDF film was observed by means of scanning electron microscopy and chemical changes by X-ray photoelectron spectroscopy, with adhesion of polypyrrole (PPy) by abrasion tests and sheet resistance measurements. Results showed that the increase in roughness and surface functionalization by oxygen functional groups contributed to improved adhesion and Ar + O2 plasma gave better adhesion.

Improvement of polypyrrole coating adhesion by radio frequency plasma

Tariq worked in the area of electronic textiles. He coated polyester fabric and PVDF films with polypyrrole. Plasma treatment was used to improve binding of coatings over the surface. He investigated in detail, the factors responsible for adhesion improvement using XPS, AFM, SEM, contact angle, abrasion tests and conductivity measurements. Different plasma gases, plasma power and plasma modes were investigated to get optimum bonding data. His investigations pointed towards improved surface oxygen functionalization and suitable surface morphology for improved bonding.

The rhetoric of ‘community’ : ABC local radio's coverage of the 2009 Victorian bushfires

This article joins recent debates in media and communication studies concerning audience participation in news journalism. Specifically, we investigate the impact of an increasing reliance on audience-generated content on newsroom practice in traditional media organisations. We do this by recounting and analysing the experiences of journalists involved in ABC Radio's coverage of the dramatic Victorian bushfires of early 2009, which relied heavily in listener contributions and was closely integrated with the ABC's online coverage. Interviews with two staff at ABC Gippsland, and the ABC's Manager of Emergency Broadcasting provide the basis for a case study of the kinds of tensions that media workers routinely confront within an organisation like the ABC. The interviews suggest that in negotiating the possibility of increased audience participation, journalists and their managers are thinking about much more that the rhetorics of democracy and the validity of news values: their focus is also on a complex structure, the need for skill (re)development and the precise mechanics of creating and maintaining productive relationships with local communities. The significance of the research lies in its attempt to bring together a number of related factors: the increasingly active role of audiences in generating and supplying news content; the impact of digital communications technologies on news production practices; and the ABC's ongoing development of its now contested role as an 'emergency broadcaster'.

Viewpoints, creativity and embodied learning : developing perceptual and kinaesthetic skills in non-dancers studying undergraduate university drama

Viewpoints are a structural approach to training and directing for theatre. Originating from the innovative, inventive and exploratory approach of Mary Overlie and the self- confessed scavenger approach of Anne Bogart, Viewpoints offers a practical philosophy of working. As a training approach it begins with a disciplined engagement  of the body in space and time. The tangible elements of the Viewpoints provide a set of tasks on which the student can focus, thus freeing the imagination and spirit to  create. Yet at the same time the systematic logic of Viewpoints supports novice practitioners to begin to question their perception, invest in creative practice that demands action and exploration, and to deconstruct, re-organise and rebuild scores and sequences in the pursuit of theatre that is visceral and visual. This essay reports on undergraduate student experiences of learning Viewpoints. It interrogates the demands of embodied learning of the movement/structural system on non- ancers and examines student-actor experiences of embodied learning from multiple of subject positions – observer/participant/creator/reflector/actor.