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2008

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Opto-Vlsi Based Broadband Reconfigurable Optical Add-Drop Multiplexer, Feng Xiao, Budi Juswardy, Kamal Alameh Jan 2008

Opto-Vlsi Based Broadband Reconfigurable Optical Add-Drop Multiplexer, Feng Xiao, Budi Juswardy, Kamal Alameh

Research outputs pre 2011

In this paper, a reconfigurable optical add/drop multiplexer (ROADM) structure using an Opto-VLSI processor, two arrayed waveguide grating de/multiplexers (AWGs) and a custom-made fiber array is described. The fiber array consist of N pairs of upper and lower fibers, where each pair could function as an add, a drop or a thru multiplexers depending on the hologram generated by the Opto-VLSI processor. Experimental results show that the proposed ROADM structure has an average insertion loss of 5.5 dB for all the functions and a uniformity of 0.3 dB over a wide wavelength range from 1524 nm to 1576 nm. A …

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Opto-Vlsi-Based Reconfigurable Microwave Photonic Transversal Filter With Positive And Negative Coefficients, Feng Xiao, Budi Juswardy, Kamal Alameh Jan 2008

Opto-Vlsi-Based Reconfigurable Microwave Photonic Transversal Filter With Positive And Negative Coefficients, Feng Xiao, Budi Juswardy, Kamal Alameh

Research outputs pre 2011

A novel reconfigurable microwave photonic filter structure with positive and negative coefficients is proposed and demonstrated. The filter structure comprises two arrayed waveguide gratings, a custom-made fiber array, high-dispersion fibres, and a reconfigurable opto-VLSI processor. Positive and negative filter weights can flexibly be synthesised to realise arbitrary transfer functions. Experimental results are presented, which demonstrate the principle of the proposed filter structure.

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Men Of Steel Or Plastic Cops: The Use Of Ethnography As A Transformative Agent, Christine Teague, David Leith Jan 2008

Men Of Steel Or Plastic Cops: The Use Of Ethnography As A Transformative Agent, Christine Teague, David Leith

Research outputs pre 2011

The Perth urban rail system, like many other rail systems in Australia and overseas, is subject to crime and anti-social behaviour around the railway environs from a small minority of the travelling public. The transit officers, who form part of the security section of the Public Transport Authority, are the people employed to deal with these incidents, which can result in transit officers being injured. To fully understand the violence and antisocial behaviour that they deal with on a regular basis and develop strategies to reduce this risk of injury, it was necessary to enter their world. The researcher in …

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Reconfigurable Multi-Passband Optical Filter Using Opto-Vlsi Processor, Muhsen Aljada, Kamal Alameh Jan 2008

Reconfigurable Multi-Passband Optical Filter Using Opto-Vlsi Processor, Muhsen Aljada, Kamal Alameh

Research outputs pre 2011

A reconfigurable multi-passband optical filter of 0.5 nm linewidth and a tuning range of 8 nm is demonstrated using an opto-VLSI processor. The wavelength tunability is performed using digital phase holograms uploaded on the opto-VLSI processor.

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You've Got Mail: Accountability And End User Attitudes To Email Management, Mark Brogan, Susan Vreugdenburg Jan 2008

You've Got Mail: Accountability And End User Attitudes To Email Management, Mark Brogan, Susan Vreugdenburg

Research outputs pre 2011

In a pioneering ethnographic study of end user responses to the problem of ‘information overload’ Whittaker and Sidner (1996) found that the design of systems primarily as methods of asynchronous communication, posed significant information management problems for users. In another contemporaneous study, David Bearman (1993) extended understanding of the implications of end user email management behavior by identifying significant accountability implications for organizations arising from the use of email. Recent case studies in the United States and Australia (Leopold, 2008; Raleigh Chronicle, 2008; Strutt, and Taylor, 2007) have once again focused attention on the accountability consequences for Government of email …

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A Novel Wide-Angle Laser Triangulation Method For Obstacle Detection, Kaveh Sahba, Kamal Alameh, Clifton Smith Jan 2008

A Novel Wide-Angle Laser Triangulation Method For Obstacle Detection, Kaveh Sahba, Kamal Alameh, Clifton Smith

Research outputs pre 2011

Indoor active triangulation to laser spots generated by quasi-cylindrical cavity is demonstrated. Principal ray trajectory is modeled using a system of linear equations and fundamental ray geometry. Each ray’s unique outgoing angle and baseline is calculated and used to derive the range to the corresponding spot. Above 98% accuracy is achieved over an approximate range of 5m, demonstrating a novel motionless laser scanning technique with a wide scanned angle and no moving parts.

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Pax7 Is Requisite For Maintenance Of A Subpopulation Of Superior Collicular Neurons And Shows A Diverging Expression Pattern To Pax3 During Superioir Collicular Development, Jennifer Thompson, Andreas Zembrzycki, Ahmed Mansouri, Melanie Ziman Jan 2008

Pax7 Is Requisite For Maintenance Of A Subpopulation Of Superior Collicular Neurons And Shows A Diverging Expression Pattern To Pax3 During Superioir Collicular Development, Jennifer Thompson, Andreas Zembrzycki, Ahmed Mansouri, Melanie Ziman

Research outputs pre 2011

Pax7 encodes a transcription factor well-established as an important determinant of mesencephalic identity and superior collicular development. Pax7 mutant mice, however, present with no obvious morphological impairments to the superior colliculus. This finding is paradoxical and has been attributed to functional redundancy afforded by its paralogue Pax3. Here we utilise Pax7 mutant mice to investigate the precise role of this important developmental regulator during superior collicular development and neuronal specification/differentiation. We also assess its spatiotemporal relationship with Pax3 during embryonic development. Analysis of the superior colliculus of Pax7 mutant and wildtype mice at a variety of developmental timepoints revealed that …

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Analysis Of Information Remaining On Hand Held Devices For Sale On The Second Hand Market, Andrew Jones, Craig Valli, Iain Sutherland Jan 2008

Analysis Of Information Remaining On Hand Held Devices For Sale On The Second Hand Market, Andrew Jones, Craig Valli, Iain Sutherland

Research outputs pre 2011

The ownership and use of mobile phones, Personal Digital Assistants and other hand held devices is now ubiquitous both for home and business use. The majority of these devices have a high initial cost, a relatively short period before they become obsolescent and a relatively low second hand value. As a result of this, when the devices are replaced, there are indications that they tend to be discarded. As technology has continued to develop, it has led to an increasing diversity in the number and type of devices that are available, and the processing power and the storage capacity of …

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A Novel Mobile Wimax Solution For Higher Throughput, Iftekhar Ahmad, Daryoush Habibi Jan 2008

A Novel Mobile Wimax Solution For Higher Throughput, Iftekhar Ahmad, Daryoush Habibi

Research outputs pre 2011

The IEEE 802.16 standard, also known as WiMAX, has emerged as an exciting technology for broadband wireless communications with potentials to offer high throughput and support high bandwidth demanding applications. WiMAX, however, has yet to prove its effectiveness when the end terminals are not fixed and have the capacity to move from one place to another at different speeds. Recent studies suggest that while WiMAX (802.16e) has the potential to deliver a data rate up to 75 Mb/s for fixed wireless communications, it fails drastically for mobile wireless communications, often providing a data rate less than 1 Mb/s when the …

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A Proactive Forward Error Control Scheme For Mobile Wimax Communication, Iftekhar Ahmad, Daryoush Habibi Jan 2008

A Proactive Forward Error Control Scheme For Mobile Wimax Communication, Iftekhar Ahmad, Daryoush Habibi

Research outputs pre 2011

The IEEE 802.16 standard, also known as WiMAX, has yet to prove its effectiveness when the end terminals are not static and free to move at vehicular speeds. High bit error rate caused by multipath fading at high vehicular speeds, is the key reason for low throughput at high speeds. Standard error control mechanisms like transmission control protocol (TCP) and forward error correction (FEC) have limited impact on the overall throughput at vehicular speeds. In this paper, we propose a proactive FEC scheme that adjusts the FEC code size based on the estimated bit error rate at various vehicular speeds. …

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Source Localisation In Wireless Sensor Networks Based On Optimised Maximum Likelihood, Mohammed Rahman, Daryoush Habibi, Iftekhar Ahmad Jan 2008

Source Localisation In Wireless Sensor Networks Based On Optimised Maximum Likelihood, Mohammed Rahman, Daryoush Habibi, Iftekhar Ahmad

Research outputs pre 2011

Maximum likelihood (ML) is a popular and effective estimator for a wide range of diverse applications and currently affords the most accurate estimation for source localisation in wireless sensor networks (WSN). ML however has two major shortcomings namely, that it is a biased estimator and is also highly sensitive to parameter perturbations. An Optimisation to ML (OML) algorithm was introduced that minimises the sum-of-squares bias and exhibits superior performance to ML in statistical estimation, particularly with finite datasets. This paper proposes a new model for acoustic source localisation in WSN, based upon the OML estimation process. In addition to the …

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An Improved Fec Scheme For Mobile Wireless Communication At Vehicular Speeds, Iftekhar Ahmad, Daryoush Habibi, Ziaur Rahman Jan 2008

An Improved Fec Scheme For Mobile Wireless Communication At Vehicular Speeds, Iftekhar Ahmad, Daryoush Habibi, Ziaur Rahman

Research outputs pre 2011

WiMAX has emerged as a promising wireless communication technology with potential to deliver high throughput and guaranteed quality of service to the end applications. Recent studies suggest that while WiMAX (802.16e) is capable of delivering a data rate of up to 75 Mbps for fixed wireless communications, data rate decreases drastically for mobile wireless communications, often providing a data rate less than 1 Mb/s when the mobile nodes travel at vehicular speeds. High bit error rate caused at high vehicular speeds is the key reason for low throughput. In noisy mobile communication environments, standard error control mechanisms like the transmission …

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Fast Evaluation Of The Square Root And Other Nonlinear Functions In Fpga, Stefan Lachowicz, Hans-Joerg Pfleiderer Jan 2008

Fast Evaluation Of The Square Root And Other Nonlinear Functions In Fpga, Stefan Lachowicz, Hans-Joerg Pfleiderer

Research outputs pre 2011

The paper presents a novel method of evaluating the square root function in FPGA. The method uses a linear approximation subsystem with a reduced size of a look-up table. The reduction in the size of the lookup table is twofold. Firstly, a simple linear approximation subsystem uses the lookup table only for the node points. Secondly, a concept of a variable step look-up table is introduced, where the node points are not uniformly spaced, but the spacing is determined by how close to the linear function the approximated function is. The proposed method of evaluating nonlinear function and specifically the …

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Performance Evaluation Of Ieee 802.15.4 For Mobile Sensor Network, Kartinah Zen, Daryoush Habibi, Alexander Rassau, Iftekhar Ahmad Jan 2008

Performance Evaluation Of Ieee 802.15.4 For Mobile Sensor Network, Kartinah Zen, Daryoush Habibi, Alexander Rassau, Iftekhar Ahmad

Research outputs pre 2011

The IEEE 802.15.4 standard medium access control (MAC) protocol for low rate wireless personal area networks (LRWPAN) is design mainly for static sensor networks and its capability to support mobile sensor networks has not yet been established. To the best knowledge of authors, this is the first paper that evaluates the suitability of IEEE 802.15.4 MAC in mobile sensor networks environment. We evaluate the performance based on node's speed and beacon order, and observe the effect on energy usage, packet delivery ratio and time required to associate with its coordinator. From the experiment we observe that the moving nodes experienced …

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Improving Mobile Sensor Connectivity Time In The Ieee 802.15.4 Networks, Kartinah Zen, Daryoush Habibi, Iftekhar Ahmad Jan 2008

Improving Mobile Sensor Connectivity Time In The Ieee 802.15.4 Networks, Kartinah Zen, Daryoush Habibi, Iftekhar Ahmad

Research outputs pre 2011

In the IEEE 802.15.4 medium access control (MAC) protocol for wireless sensor networks, a sensor node needs to associate with a coordinator before it starts sending or receiving data. The sensor node will mostly choose the nearest coordinator to associate with. However, this method is not suitable for a constantly moving sensor node because it will end up switching coordinators too often due to short connectivity time. The IEEE 802.15.4 has a simplistic and inadequate method of choosing a coordinator in this context. In this paper, we introduce a method to increase the mobile sensor node connectivity time with its …

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Soft Computing In The Forecasting Of The Stock Exchange Of Thailand, Suchira Chaigusin, Chaiyaporn Chirathamjaree, Judith Clayden Jan 2008

Soft Computing In The Forecasting Of The Stock Exchange Of Thailand, Suchira Chaigusin, Chaiyaporn Chirathamjaree, Judith Clayden

Research outputs pre 2011

Stock markets are affected by many uncertainties and interrelated economic and political factors at both local and global levels; determining the set of relevant factors for making accurate predictions is a complicated task. This paper analyzes relevant literature on the Stock Exchange of Thailand (SET), according to the categories of techniques used. The research proposes an approach of soft computing on the SET forecasting and exposes the main driving indicators, from the literature, including Dow Jones, Nikkei index, Hang Seng index, Minimum Loan Rate, the value of the Thai baht and the gold price.

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The Use Of Neural Networks In The Prediction Of The Stock Exchange Of Thailand (Set) Index, Suchira Chaigusin, Chaiyaporn Chirathamjaree, Judith Clayden Jan 2008

The Use Of Neural Networks In The Prediction Of The Stock Exchange Of Thailand (Set) Index, Suchira Chaigusin, Chaiyaporn Chirathamjaree, Judith Clayden

Research outputs pre 2011

Prediction of stock prices is an issue of interest to financial markets. Many prediction techniques have been reported in stock forecasting. Neural networks are viewed as one of the more suitable techniques. In this study, an experiment on the forecasting of the Stock Exchange of Thailand (SET) was conducted by using feedforward backpropagation neural networks. In the experiment, many combinations of parameters were investigated to identify the right set of parameters for the neural network models in the forecasting of SET. Several global and local factors influencing the Thai stock market were used in developing the models, including the Dow …

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Towards Automated Test Sequence Generation, Usman Farooq, Chiou Peng Lam, Huaizhong Li Jan 2008

Towards Automated Test Sequence Generation, Usman Farooq, Chiou Peng Lam, Huaizhong Li

Research outputs pre 2011

The article presents a novel control-flow based test sequence generation technique using UML 2.0 activity diagram, which is a behavioral type of UML diagram. Like other model-based techniques, this technique can be used in the earlier phases of the development process owing to the availability of the design models of the system. The activity diagram model is seamlessly converted into a colored Petri net. We proposed a technique that enables the automatic generation of test sequences according to a given coverage criteria from the execution of the colored Petri nets model. Two types of structural coverage criteria for AD based …

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Supporting Component Selection With A Suite Of Classifiers, Valerie Maxville, Chiou Peng Lam, J Armarego Jan 2008

Supporting Component Selection With A Suite Of Classifiers, Valerie Maxville, Chiou Peng Lam, J Armarego

Research outputs pre 2011

Software selection involves the assimilation of information and results for each candidate to enable a comparison for decisions to be made. The processes and tools developed assist with software selection to enhance quality, documentation and repeatability. The CdCE process aims to retain and document the information used in selection to assist decisions and to document them for reference as the system evolves. This paper describes the CdCE process and our approach to assist the shortlisting of candidates through a suite of classifiers. The application of the suite is illustrated using a selection and evaluation case study. Applying this approach helps …

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Morphology Independent Dynamic Locomotion Control For Virtual Characters, Adrian Boeing Jan 2008

Morphology Independent Dynamic Locomotion Control For Virtual Characters, Adrian Boeing

Research outputs pre 2011

Physically based animation of virtual characters is an attractive technology for computer games. It enables characters to dynamically react to interactions with the environment. Existing dynamic simulation controllers are often complex to understand and manipulate, and so are of limited use for animators. This paper presents an extended spline-based control strategy similar to splines used in standard keyframe animation techniques. Unlike existing dynamic control strategies, this allows animators to modify the control system parameters in a manner similar to traditional kinematic animation techniques. A genetic algorithm is employed to produce the initial control parameters for the desired gait, and extend …

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Mutation Analysis For The Evaluation Of Ad Models, Usman Farooq, Chiou Peng Lam Jan 2008

Mutation Analysis For The Evaluation Of Ad Models, Usman Farooq, Chiou Peng Lam

Research outputs pre 2011

UML has became the industry standard for analysis and design modeling. Model is a key artifact in Model Driven Architect (MDA) and considered as an only concrete artifact available at earlier development stages. Error detection at earlier development stages can save enormous amount of cost and time. The article presents a novel mutation analysis technique for UML 2.0 Activity Diagram (AD). Based on the AD oriented fault types, a number of mutation operators are defined. The technique focuses on the key features of AD and enhances the confidence in design correctness by showing the absence of control-flow and concurrency related …

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Optimized Wlan Mac Protocol For Multimedia Applications, Hushairi Zen, Daryoush Habibi, Alexander Rassau, Iftekhar Ahmad Jan 2008

Optimized Wlan Mac Protocol For Multimedia Applications, Hushairi Zen, Daryoush Habibi, Alexander Rassau, Iftekhar Ahmad

Research outputs pre 2011

In this paper we propose an optimized WLAN MAC protocol for multimedia applications. The proposed MAC protocol consist of 3 main optimizing architectures, traffic segregation, specific service interval (SI) for voice and video traffic and smaller contention window (CW). Traffic segregation segregates real-time traffic from best-effort traffic while specific service interval provides voice and video traffic with the SI based on its mean arrival rate. In the contention time frame, the CW is made smaller to reduce delay and increase throughput. Ns2 is used as a simulating tool to compare the results of our proposed protocol with the legacy 802.11 …

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Self-Restraint Admission Control For Ad-Hoc Wlans, Hushairi Zen, Daryoush Habibi, Iftekhar Ahmad Jan 2008

Self-Restraint Admission Control For Ad-Hoc Wlans, Hushairi Zen, Daryoush Habibi, Iftekhar Ahmad

Research outputs pre 2011

Admission control is an important mechanism for sustaining throughput and supporting quality of service (QoS) for real-time traffic in a wireless local area network (WLAN). In an adhoc WLAN scenario where no access point (AP) is available, admission control has to be self-managed by each node. We propose a self-restraining admission control mechanism that works by monitoring the congestion level of the network in the adhoc WLAN. Wireless nodes can listen to all nodes within their range and be aware of the collision rates. A node wishing to join the network measures the current collision rate, and predicts the post-admission …

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The Potential Role Of Life-Writing Therapy In Facilitating 'Recovery' For Those With Mental Illness, Philip Max Neilsen, Ffion Murphy Jan 2008

The Potential Role Of Life-Writing Therapy In Facilitating 'Recovery' For Those With Mental Illness, Philip Max Neilsen, Ffion Murphy

Research outputs pre 2011

This article addresses the experience of designing and conducting life-writing workshops for a group of clients with severe mental illness; the aim of this pilot study was to begin to determine whether such writing about the self can aid in individual ‘recovery’, as that term is understood by contemporary health professionals. A considerable amount has been written about the potential of creative writing in mental health therapy; the authors of this article provide a brief summary of that literature, then of the concept of ‘recovery’ in a psychology and arts therapy context. There follows a first-hand account by one of …

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Converging Voice, Video And Data In Wlan With Qos Support, Hushairi Zen, Daryoush Habibi, Justin Wyatt, Iftekhar Ahmad Jan 2008

Converging Voice, Video And Data In Wlan With Qos Support, Hushairi Zen, Daryoush Habibi, Justin Wyatt, Iftekhar Ahmad

Research outputs pre 2011

Providing quality of service (QoS) for converging traffic in wireless local area network (WLAN) is still a major issue for the researchers and industries. Due to the limited bandwidth and exposure to unpredictable interferences in a wireless environment, efficient management and optimization of the access protocols are essential to provide acceptable QoS for real-time traffic and fairness to best-effort traffic. In this paper, we investigate the throughput and delay performance of the legacy IEEE 802.11 and the 802.11e when carrying converging data in WLAN. We evaluate our recently proposed protocol known as wireless token network protocol (WTN) and show that …

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Node Admission Control For Multimedia Traffic In Ad-Hoc Wlans, Hushairi Zen, Daryoush Habibi, Iftekhar Ahmad, Alexander Rassau Jan 2008

Node Admission Control For Multimedia Traffic In Ad-Hoc Wlans, Hushairi Zen, Daryoush Habibi, Iftekhar Ahmad, Alexander Rassau

Research outputs pre 2011

In this paper, we design an admission control scheme for ad hoc WLAN based on self-restraint mechanism. The self-restraint admission control mechanism is implemented in each of the wireless nodes instead of the access point (AP). It has two important admission control abilities: first, it can restrain itself from joining the network if the network channel is congested; second, a joining node can drop itself from the network if the channel becomes congested as a result of its admission. We simulate an ad hoc WLAN and show that the self-restraining mechanism works effectively in sustaining traffic in ad hoc WLAN …

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Using Design-Based Research For The Evolutionary Development Of An Online Metacognitive Tool, Joseph Luca, Mark Mcmahon Jan 2008

Using Design-Based Research For The Evolutionary Development Of An Online Metacognitive Tool, Joseph Luca, Mark Mcmahon

Research outputs pre 2011

No abstract provided.

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Creating A Web-Based Knowledge-Building Team: Design Of Tasks, Scaffolds And Social Affordances, Catherine Mcloughlin, Joseph Luca Jan 2008

Creating A Web-Based Knowledge-Building Team: Design Of Tasks, Scaffolds And Social Affordances, Catherine Mcloughlin, Joseph Luca

Research outputs pre 2011

In a blended learning environment, where students undertake professional skills development in the workplace, a flexible environment is designed in order to support problem solving in project management. The design of the environment, informed by socio-cultural theory, was intended to support knowledge building among students, and in particular to support exchange of ideas, peer review and commentary on solutions presented to problems, and a reflective space for exchange of ideas. The online environment incorporates a number of functional affordances that scaffold knowledge exchange, collaborative tasks and peer commentary. The design features of the online site are described and a proposed …

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Photography After The Incidents: We're Not Afraid, Panizza Allmark Jan 2008

Photography After The Incidents: We're Not Afraid, Panizza Allmark

Research outputs pre 2011

This article will look at the use of personal photographs that attempt to convey a sense of social activism as a reaction against global terrorism. Moreover, I argue that the photographs uploaded to the site “We’re Not Afraid”, which began after the London bombings in 2005, presents a forum to promote the pleasures of western cultural values as a defence against the anxiety of terror. What is compelling are the ways in which the Website promotes, seemingly, everyday modalities through what may be deemed as the domestic snapshot. Nevertheless, the aura from the context of these images operates to arouse …

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Novel Broadband Reconfigurable Optical Add-Drop Multiplexer Employing Custom Fiber Arrays And Opto-Vlsi Processors, Feng Xiao, Budi Juswardy, Kamal Alameh, Yong Tak Lee Jan 2008

Novel Broadband Reconfigurable Optical Add-Drop Multiplexer Employing Custom Fiber Arrays And Opto-Vlsi Processors, Feng Xiao, Budi Juswardy, Kamal Alameh, Yong Tak Lee

Research outputs pre 2011

A reconfigurable optical add/drop multiplexer (ROADM) structure based on using a custom-made fiber array and an Opto-VLSI processor is proposed and demonstrated. The fiber array consists of N pairs of angled fibers corresponding to N channels, each of which can independently perform add, drop, and thru functions through a reconfigurable Opto-VLSI beam steerer. Experimental results show that the ROADM structure can attain an average add, drop/thru insertion loss of 5.5 dB and a uniformity of 0.3 dB over a wide bandwidth from 1524 nm to 1576 nm, and a drop/thru crosstalk level as small as -40 dB.

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