Effects of baffles on flow distribution in an electrostatic precipitator (ESP) of a coal based power plant

Electrostatic Precipitators (ESP) are the most reliable and industrially used control devices to capture fine particles for reducing exhaust emission. Its efficiency is 99% or more. However, capturing submicron particles which are hazardous is still a problem as it involves complex flow phenomena and ESP design limitations. In this study, the effect of baffles on flow distribution inside the ESP is investigated computationally. Baffles are expected to increase the residence time of flue gas which helps to collect more particles into the collector plates, and hence increase the collection efficiency of an ESP. Besides, the placement of a baffle is likely to cause swirling of flue gas and hence sub-micron particles move towards the collector plate due to eccentric and electrostatic force. Therefore, the effects of position, shape and thickness of the baffles on collection efficiency which are also important for ESP design are reported in this study. The fluid flow distribution has been modelled using computational fluid dynamics (CFD) software Fluent and the result and outcome are presented and discussed. The result shows that baffles have significant influence on fluid flow pattern and the efficiency of ESP.

Location based power control for mobile devices in a cellular network

This paper provides location estimation based power control strategy for cellular radio systems via a location based interference management scheme. Our approach considers the carrier-to-interference as dependent on the transmitter and receiver separation distance and therefore an accurate estimation of the precise locations can provide the power critical mobile user to control the transition power accordingly. In this fully
distributed algorithms, we propose using a Robust Extended Kalman Filter (REKF) to derive an estimate of the mobile user’s closest mobile base station from the user’s location, heading and altitude. Our analysis demonstrates that this algorithm can successfully track the mobile users with less system complexity, as it requires measurements from only one or two closest mobile base stations and hence enable the user to transmit at the rate that is sufficient for the interference management. Our power control
algorithms based on this estimation converges to the desired power trajectory. Further, the technique is robust against system uncertainties caused by the inherent deterministic nature of the mobility model. Through simulation, we show the accuracy of our prediction algorithm and the simplicity of its implementation.

Detecting SMS-based control commands in a Botnet from infected android devices

An increasing number of Android devices are being infected and at risk of becoming part of a botnet. Among all types of botnets, control and cornmand based botnets are very popular. In this paper we introduce an effective and efficient method to ddect SMS-based control commands ftvm infected Android devices. Specifically, we rely on the important radio activities recorded in Android log files. These radio activities are currently overlooked by researchers. We show the effectiveness of our rnethod by using the examples frorn published literature. Our method requires much less user knowledge but is more generic than traditional approaches.

A comparative analysis of opinions of Americans, Australians and Malaysians on the use of biometric devices in workplaces for security and monitoring of worker productivity

Since the September 11, 2001 terrorist attacks in New York, the use of biometric devices such as fingerprint scans, retina and iris scans and facial recognition in everyday situations for national security and border control, have become commonplace. This has resulted in the biometric industry moving from being a niche technology to one that is ubiquitous. As a result. more and more employers are using biometrics to secure staff access to their facilities as well as for tracking staff work hours, maintaining 'discipline' and carry out surveillance against thefts. detecting work hour abuses and fraud. However, the data thus collected and the technologies themselves are feared of having the potential for and actually being misused - both in terms of the violating staff privacy and discrimination and oppression of targeted workers. This paper examines the issue of using biometric devices in organisational settings their advantages, disadvantages and actual and potential abuses from the point of view of critical theory. From the perspectives of Panoptic surveillance and hegemonic organisational control, the paper examines the issues related to privacy and identification, biometrics and privacy, biometrics and the 'body', and surveillance and modernity. The paper also examines the findings ofa survey carried out in Australia. Malaysia and the USA on respondents' opinions on the use of biometric devices in everyday life including at workplaces. The paper concludes that along with their applications in border control and national security, the use of biometric devices should be covered by relevant laws and regulations. guidelines and codes of practice. in order to balance the rights to privacy and civil liberties of workers with employers' need for improved productivity, reduced costs, safeguards related to occupational health and safety, equal opportunity, and workplace harassment of staff and other matters, that employers are legally responsible for.

Investigation into and control of microwave induced thermal run-away

Analyses the mechanisms that cause thermal run-away in some materials. A control strategy was devised to provide effective temperature control independent of material characteristics. The set of control criteria derived from mathematical models allowed the control limits of a microwave processing system to calculated.

An empirical examination of feedback : user control and performance in a hapto-audio-visual training environment

Utilising advanced technologies, such as virtual environments (VEs), is of importance to training and education. The need to develop and effectively apply interactive, immersive 3D VEs continues to grow. As with any emerging technology, user acceptance of new software and hardware devices is often difficult to measure and guidelines to introduce and ensure adequate and correct usage of such technologies are lacking. It is therefore imperative to obtain a solid understanding of the important elements that play a role in effective learning through VEs. In particular, 3D VEs may present unusual and varied interaction and adoption considerations. The major contribution of this study is to investigate a complex set of interrelated factors in the relatively new sphere of VEs for training and education. Although many of the factors appears to be important from past research, researcher have not explicitly studied a comprehensive set of inter-dependant, empirically validated factors in order to understand how VEs aid complex procedural knowledge and motor skill learning. By integrating theory from research on training, human computer interaction (HCI), ergonomics and cognitive psychology, this research proposes and validates a model that contributes to application-specific VE efficacy formation. The findings of this study show visual feedback has a significant effect on performance. For tactile/force feedback and auditory feedback, no significant effect were found. For satisfaction, user control is salient for performance. Other factors such as interactivity and system comfort, as well as level of task difficulty, also showed effects on performance.

Integrated microfluidic drug delivery devices : a component view

Research on drug delivery devices is progressing rapidly with the main objective being the delivery of precise quantity of drugs into the target area of the body. A drug delivery device (DDD) needs to accurately control the flow rate of drug delivery and protects the body from undesired additional doses. An integrated microfluidic drug delivery device (IMDDD) is a miniature device that can regulate and monitor the delivery of the right amount of drug using micro-scale components. IMDDDs offer several advantages including ease of use, electro-chemical controllability, low power consumption, simplicity, fast fabrication, and good bio-compatibility. Various IMDDDs have been developed for treatment of cancer, cardiovascular disorder, eye and brain diseases, stress, and diabetes. This paper presents a generic architecture for IMDDDs, discusses the existing drug delivery methods, summarizes the specifications of the components, and identifies a number of performance evaluation parameters. The operation of IMDDDs is presented through fourteen potential internal components. In addition, recommendations on how enhance the design and fabrication process of IMDDDs are given.

Design, characterization and application of a novel mono-layer pin-microvalve for microfluidic devices

Valves are one of the key components in microfluidic devices to control the fluid flow. In this paper we introduce a novel manual pin-valve which can operate in both analogue (partially close) and digital (on/off) states. We also demonstrate implementation of this pin-valve in a hydrodynamic flow focusing (HFF) device. © The Royal Society of Chemistry 2014.

Keyboard control method for virtual reality micro-robotic cell injection training

The rapid development of virtual reality offers significant potential for skills training applications. Our ongoing work proposes virtual reality operator training for the micro-robotic cell injection procedure. The interface between the operator and the system can be achieved in many different ways. The computer keyboard is ubiquitous in its use for everyday computing applications and also commonly utilized in virtual reality systems. Based on the premise that most people have experience in using a computer keyboard, as opposed to more sophisticated input devices, this paper considers the feasibility of using a keyboard to control the micro-robot for cell injection. In this study, thirteen participants underwent the experimental evaluation. The participants were asked to perform three simulated trial sessions in a virtual micro-robotic cell injection environment. Each session consisted of ten cell injection trials and relevant data for each trial were recorded and analyzed. Results showed participants' performance improvement after the three sessions. It was also observed that participants intuitively controlled multiple axes of the micro-robot simultaneously despite the absence of instruction on how to do so. This continued throughout the experiments and suggests skills transfer from other keyboard based interactions. Based on the results provided, it is suggested that keyboard control is a feasible, simple and low-cost control method for the virtual micro-robot.

A lightweight virtualization solution for android devices

Mobile virtualization has emerged fairly recently and is considered a valuable way to mitigate security risks on Android devices. However, major challenges in mobile virtualization include runtime, hardware, resource overhead, and compatibility. In this paper, we propose a lightweight Android virtualization solution named Condroid, which is based on container technology. Condroid utilizes resource isolation based on namespaces feature and resource control based on cgroups feature. By leveraging them, Condroid can host multiple independent Android virtual machines on a single kernel to support mutilple Android containers. Furthermore, our implementation presents both a system service sharing mechanism to reduce memory utilization and a filesystem sharing mechanism to reduce storage usage. The evaluation results on Google Nexus 5 demonstrate that Condroid is feasible in terms of runtime, hardware resource overhead, and compatibility. Therefore, we find that Condroid has a higher performance than other virtualization solutions.

Countering Improvised explosive devices through a multi-point haptic teleoperation system

Improvised Explosive Devices (IEDs) are reported as the number one cause of injury and death for allied troops in the current theater of operation. Current stand-off technologies for Counter IED (CIED) tasks rely on robotic platforms that have not improved in capability over the past decade to combat the ever increasing threat of IEDs. While they provide operational capability, the effectiveness of these platforms is limited. This is because they primarily utilise video and audio feedback, and require extensive training and specialist operators. Recent operational experience has demonstrated the need for robotic systems that are highly capable, yet easily operable for high fidelity manipulation. Force feedback provides an operator with more intuitive control of a robotic system. This sense of touch allows an operator to obtain a sense of feel from a stand-off location of what the robot touches or grasps through a human-robot interface. This paper reports the design and development of a Haptically-Enabled Counter IED robotic system that was funded by the Australian Defence Force. The presented work focuses on the design methodology for the system, and provides the results of the manipulator analysis and trial outcomes.

Restricting access to invasion hubs enables sustained control of an invasive vertebrate

Biological invasions often occur through expansion of satellite populations that become established at 'invasion hubs'. Invasion hubs can result from random dispersal events, but frequently arise when invading individuals actively choose habitats using cues that signify high-quality environments where the fitness consequences are positive. Theoretical studies suggest that targeted control at invasion hubs can effectively suppress the populations and impacts of invaders. In arid Australia, small dams that provide water for livestock function as invasion hubs by providing an invasive vertebrate, the cane toad Rhinella marina, with refuge from extreme aridity during the annual dry season. Toads are attracted to dams and use them as stepping stone habitats from which they disperse during rainy periods. Here, we ask whether sustained control of this invasive vertebrate can be achieved by converting invasion hubs into ecological traps. We did this by manipulating invasion hub habitats to induce a mismatch between toads' habitat preference and the fitness consequences of their habitat choice to cause high mortality. We constructed fences to exclude toads from dams and maintained these fences for 1 year. This period encompassed periods of dry and wet seasonal climatic conditions. Our manipulation did not alter the attractive cues for invading toads which died en masse while attempting to settle at fenced dams that prevented toads from reaching water. Toad populations at the fenced dams were suppressed by 1-2 orders of magnitude compared to unfenced controls and procedural controls. Toad populations remained suppressed for a year after exclusion. By excluding toads from dams, we converted invasion hubs into ecological traps and effectively thwarted the reinvasion of cane toads. Our research suggests that water exclusion devices could be used to prevent toad invasion or to control cane toad populations in arid landscapes colonized by toads. Synthesis and applications. Our study demonstrates that sustained control of invader populations can be achieved by restricting their access to invasion hubs. Control of invasive species via elimination of invasion hubs could be conducted reactively, to control established populations of invaders, or conducted strategically, by rendering invasion hubs unsuitable for colonization ahead of the invasion front to prevent further population spread.

Power management and control strategies for efficient operation of a solar power dominated hybrid DC microgrid for remote power applications

In this paper, a hybrid DC microgrid consisting of a diesel generator with a rectifier, a solar photovoltaic (PV) system, and a battery energy storage system is presented in relation to an effective power management strategy and different control techniques are adopted to power electronic interfaces. The solar PV and battery energy storage systems are considered as the main sources of energy sources that supply the load demand on a daily basis whereas the diesel generator is used as a backup for the emergency operation of the microgrid. All system components are connected to a common DC bus through an appropriate power electronics devices (e.g., rectifier systems, DC/DC converter). Also a detailed sizing philosophy of all components along with the energy management strategy is proposed. Energy distribution pattern of each individual component has been conducted based on the monthly basis along with a power management algorithm. The power delivered by the solar PV system and diesel generator is controlled via DC-DC converterand excitation controllers which are designed based on a linearquadratic regulator (LQR) technique as as proportional integral (PI)controllers. The component level power distribution is investigatedusing these controllers under fluctuating load and solar irradiationconditions and comparative results are presented.